Subversion Repositories Kolibri OS

Rev

Blame | Last modification | View Log | Download | RSS feed

  1. /* cairo - a vector graphics library with display and print output
  2.  *
  3.  * Copyright © 2002 University of Southern California
  4.  * Copyright © 2005 Red Hat, Inc.
  5.  *
  6.  * This library is free software; you can redistribute it and/or
  7.  * modify it either under the terms of the GNU Lesser General Public
  8.  * License version 2.1 as published by the Free Software Foundation
  9.  * (the "LGPL") or, at your option, under the terms of the Mozilla
  10.  * Public License Version 1.1 (the "MPL"). If you do not alter this
  11.  * notice, a recipient may use your version of this file under either
  12.  * the MPL or the LGPL.
  13.  *
  14.  * You should have received a copy of the LGPL along with this library
  15.  * in the file COPYING-LGPL-2.1; if not, write to the Free Software
  16.  * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
  17.  * You should have received a copy of the MPL along with this library
  18.  * in the file COPYING-MPL-1.1
  19.  *
  20.  * The contents of this file are subject to the Mozilla Public License
  21.  * Version 1.1 (the "License"); you may not use this file except in
  22.  * compliance with the License. You may obtain a copy of the License at
  23.  * http://www.mozilla.org/MPL/
  24.  *
  25.  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
  26.  * OF ANY KIND, either express or implied. See the LGPL or the MPL for
  27.  * the specific language governing rights and limitations.
  28.  *
  29.  * The Original Code is the cairo graphics library.
  30.  *
  31.  * The Initial Developer of the Original Code is University of Southern
  32.  * California.
  33.  *
  34.  * Contributor(s):
  35.  *      Carl D. Worth <cworth@cworth.org>
  36.  */
  37.  
  38. #include "cairoint.h"
  39.  
  40. #include "cairo-clip-private.h"
  41. #include "cairo-error-private.h"
  42. #include "cairo-gstate-private.h"
  43.  
  44. #if _XOPEN_SOURCE >= 600 || defined (_ISOC99_SOURCE)
  45. #define ISFINITE(x) isfinite (x)
  46. #else
  47. #define ISFINITE(x) ((x) * (x) >= 0.) /* check for NaNs */
  48. #endif
  49.  
  50. static cairo_status_t
  51. _cairo_gstate_init_copy (cairo_gstate_t *gstate, cairo_gstate_t *other);
  52.  
  53. static cairo_status_t
  54. _cairo_gstate_ensure_font_face (cairo_gstate_t *gstate);
  55.  
  56. static cairo_status_t
  57. _cairo_gstate_ensure_scaled_font (cairo_gstate_t *gstate);
  58.  
  59. static void
  60. _cairo_gstate_unset_scaled_font (cairo_gstate_t *gstate);
  61.  
  62. static cairo_status_t
  63. _cairo_gstate_transform_glyphs_to_backend (cairo_gstate_t      *gstate,
  64.                                            const cairo_glyph_t *glyphs,
  65.                                            int                  num_glyphs,
  66.                                            const cairo_text_cluster_t   *clusters,
  67.                                            int                   num_clusters,
  68.                                            cairo_text_cluster_flags_t cluster_flags,
  69.                                            cairo_glyph_t       *transformed_glyphs,
  70.                                            int                  *num_transformed_glyphs,
  71.                                            cairo_text_cluster_t *transformed_clusters);
  72.  
  73. static void
  74. _cairo_gstate_update_device_transform (cairo_observer_t *observer,
  75.                                        void *arg)
  76. {
  77.     cairo_gstate_t *gstate = cairo_container_of (observer,
  78.                                                  cairo_gstate_t,
  79.                                                  device_transform_observer);
  80.  
  81.     gstate->is_identity = (_cairo_matrix_is_identity (&gstate->ctm) &&
  82.                            _cairo_matrix_is_identity (&gstate->target->device_transform));
  83. }
  84.  
  85. cairo_status_t
  86. _cairo_gstate_init (cairo_gstate_t  *gstate,
  87.                     cairo_surface_t *target)
  88. {
  89.     cairo_status_t status;
  90.  
  91.     VG (VALGRIND_MAKE_MEM_UNDEFINED (gstate, sizeof (cairo_gstate_t)));
  92.  
  93.     gstate->next = NULL;
  94.  
  95.     gstate->op = CAIRO_GSTATE_OPERATOR_DEFAULT;
  96.  
  97.     gstate->tolerance = CAIRO_GSTATE_TOLERANCE_DEFAULT;
  98.     gstate->antialias = CAIRO_ANTIALIAS_DEFAULT;
  99.  
  100.     _cairo_stroke_style_init (&gstate->stroke_style);
  101.  
  102.     gstate->fill_rule = CAIRO_GSTATE_FILL_RULE_DEFAULT;
  103.  
  104.     gstate->font_face = NULL;
  105.     gstate->scaled_font = NULL;
  106.     gstate->previous_scaled_font = NULL;
  107.  
  108.     cairo_matrix_init_scale (&gstate->font_matrix,
  109.                              CAIRO_GSTATE_DEFAULT_FONT_SIZE,
  110.                              CAIRO_GSTATE_DEFAULT_FONT_SIZE);
  111.  
  112.     _cairo_font_options_init_default (&gstate->font_options);
  113.  
  114.     _cairo_clip_init (&gstate->clip);
  115.  
  116.     gstate->target = cairo_surface_reference (target);
  117.     gstate->parent_target = NULL;
  118.     gstate->original_target = cairo_surface_reference (target);
  119.  
  120.     gstate->device_transform_observer.callback = _cairo_gstate_update_device_transform;
  121.     cairo_list_add (&gstate->device_transform_observer.link,
  122.                     &gstate->target->device_transform_observers);
  123.  
  124.     gstate->is_identity = _cairo_matrix_is_identity (&gstate->target->device_transform);
  125.     cairo_matrix_init_identity (&gstate->ctm);
  126.     gstate->ctm_inverse = gstate->ctm;
  127.     gstate->source_ctm_inverse = gstate->ctm;
  128.  
  129.     gstate->source = (cairo_pattern_t *) &_cairo_pattern_black.base;
  130.  
  131.     /* Now that the gstate is fully initialized and ready for the eventual
  132.      * _cairo_gstate_fini(), we can check for errors (and not worry about
  133.      * the resource deallocation). */
  134.     status = target->status;
  135.     if (unlikely (status))
  136.         return status;
  137.  
  138.     status = gstate->source->status;
  139.     if (unlikely (status))
  140.         return status;
  141.  
  142.     return CAIRO_STATUS_SUCCESS;
  143. }
  144.  
  145. /**
  146.  * _cairo_gstate_init_copy:
  147.  *
  148.  * Initialize @gstate by performing a deep copy of state fields from
  149.  * @other. Note that gstate->next is not copied but is set to %NULL by
  150.  * this function.
  151.  **/
  152. static cairo_status_t
  153. _cairo_gstate_init_copy (cairo_gstate_t *gstate, cairo_gstate_t *other)
  154. {
  155.     cairo_status_t status;
  156.  
  157.     VG (VALGRIND_MAKE_MEM_UNDEFINED (gstate, sizeof (cairo_gstate_t)));
  158.  
  159.     gstate->op = other->op;
  160.  
  161.     gstate->tolerance = other->tolerance;
  162.     gstate->antialias = other->antialias;
  163.  
  164.     status = _cairo_stroke_style_init_copy (&gstate->stroke_style,
  165.                                             &other->stroke_style);
  166.     if (unlikely (status))
  167.         return status;
  168.  
  169.     gstate->fill_rule = other->fill_rule;
  170.  
  171.     gstate->font_face = cairo_font_face_reference (other->font_face);
  172.     gstate->scaled_font = cairo_scaled_font_reference (other->scaled_font);
  173.     gstate->previous_scaled_font = cairo_scaled_font_reference (other->previous_scaled_font);
  174.  
  175.     gstate->font_matrix = other->font_matrix;
  176.  
  177.     _cairo_font_options_init_copy (&gstate->font_options , &other->font_options);
  178.  
  179.     _cairo_clip_init_copy (&gstate->clip, &other->clip);
  180.  
  181.     gstate->target = cairo_surface_reference (other->target);
  182.     /* parent_target is always set to NULL; it's only ever set by redirect_target */
  183.     gstate->parent_target = NULL;
  184.     gstate->original_target = cairo_surface_reference (other->original_target);
  185.  
  186.     gstate->device_transform_observer.callback = _cairo_gstate_update_device_transform;
  187.     cairo_list_add (&gstate->device_transform_observer.link,
  188.                     &gstate->target->device_transform_observers);
  189.  
  190.     gstate->is_identity = other->is_identity;
  191.     gstate->ctm = other->ctm;
  192.     gstate->ctm_inverse = other->ctm_inverse;
  193.     gstate->source_ctm_inverse = other->source_ctm_inverse;
  194.  
  195.     gstate->source = cairo_pattern_reference (other->source);
  196.  
  197.     gstate->next = NULL;
  198.  
  199.     return CAIRO_STATUS_SUCCESS;
  200. }
  201.  
  202. void
  203. _cairo_gstate_fini (cairo_gstate_t *gstate)
  204. {
  205.     _cairo_stroke_style_fini (&gstate->stroke_style);
  206.  
  207.     cairo_font_face_destroy (gstate->font_face);
  208.     gstate->font_face = NULL;
  209.  
  210.     cairo_scaled_font_destroy (gstate->previous_scaled_font);
  211.     gstate->previous_scaled_font = NULL;
  212.  
  213.     cairo_scaled_font_destroy (gstate->scaled_font);
  214.     gstate->scaled_font = NULL;
  215.  
  216.     _cairo_clip_reset (&gstate->clip);
  217.  
  218.     cairo_list_del (&gstate->device_transform_observer.link);
  219.  
  220.     cairo_surface_destroy (gstate->target);
  221.     gstate->target = NULL;
  222.  
  223.     cairo_surface_destroy (gstate->parent_target);
  224.     gstate->parent_target = NULL;
  225.  
  226.     cairo_surface_destroy (gstate->original_target);
  227.     gstate->original_target = NULL;
  228.  
  229.     cairo_pattern_destroy (gstate->source);
  230.     gstate->source = NULL;
  231.  
  232.     VG (VALGRIND_MAKE_MEM_NOACCESS (gstate, sizeof (cairo_gstate_t)));
  233. }
  234.  
  235. /**
  236.  * _cairo_gstate_save:
  237.  * @gstate: input/output gstate pointer
  238.  *
  239.  * Makes a copy of the current state of @gstate and saves it
  240.  * to @gstate->next, then put the address of the newly allcated
  241.  * copy into @gstate.  _cairo_gstate_restore() reverses this.
  242.  **/
  243. cairo_status_t
  244. _cairo_gstate_save (cairo_gstate_t **gstate, cairo_gstate_t **freelist)
  245. {
  246.     cairo_gstate_t *top;
  247.     cairo_status_t status;
  248.  
  249.     if (CAIRO_INJECT_FAULT ())
  250.         return _cairo_error (CAIRO_STATUS_NO_MEMORY);
  251.  
  252.     top = *freelist;
  253.     if (top == NULL) {
  254.         top = malloc (sizeof (cairo_gstate_t));
  255.         if (unlikely (top == NULL))
  256.             return _cairo_error (CAIRO_STATUS_NO_MEMORY);
  257.     } else
  258.         *freelist = top->next;
  259.  
  260.     status = _cairo_gstate_init_copy (top, *gstate);
  261.     if (unlikely (status)) {
  262.         top->next = *freelist;
  263.         *freelist = top;
  264.         return status;
  265.     }
  266.  
  267.     top->next = *gstate;
  268.     *gstate = top;
  269.  
  270.     return CAIRO_STATUS_SUCCESS;
  271. }
  272.  
  273. /**
  274.  * _cairo_gstate_restore:
  275.  * @gstate: input/output gstate pointer
  276.  *
  277.  * Reverses the effects of one _cairo_gstate_save() call.
  278.  **/
  279. cairo_status_t
  280. _cairo_gstate_restore (cairo_gstate_t **gstate, cairo_gstate_t **freelist)
  281. {
  282.     cairo_gstate_t *top;
  283.  
  284.     top = *gstate;
  285.     if (top->next == NULL)
  286.         return _cairo_error (CAIRO_STATUS_INVALID_RESTORE);
  287.  
  288.     *gstate = top->next;
  289.  
  290.     _cairo_gstate_fini (top);
  291.     VG (VALGRIND_MAKE_MEM_UNDEFINED (&top->next, sizeof (cairo_gstate_t *)));
  292.     top->next = *freelist;
  293.     *freelist = top;
  294.  
  295.     return CAIRO_STATUS_SUCCESS;
  296. }
  297.  
  298. /**
  299.  * _cairo_gstate_redirect_target:
  300.  * @gstate: a #cairo_gstate_t
  301.  * @child: the new child target
  302.  *
  303.  * Redirect @gstate rendering to a "child" target. The original
  304.  * "parent" target with which the gstate was created will not be
  305.  * affected. See _cairo_gstate_get_target().
  306.  *
  307.  * Unless the redirected target has the same device offsets as the
  308.  * original #cairo_t target, the clip will be INVALID after this call,
  309.  * and the caller should either recreate or reset the clip.
  310.  **/
  311. cairo_status_t
  312. _cairo_gstate_redirect_target (cairo_gstate_t *gstate, cairo_surface_t *child)
  313. {
  314.     cairo_matrix_t matrix;
  315.  
  316.     /* If this gstate is already redirected, this is an error; we need a
  317.      * new gstate to be able to redirect */
  318.     assert (gstate->parent_target == NULL);
  319.  
  320.     /* Set up our new parent_target based on our current target;
  321.      * gstate->parent_target will take the ref that is held by gstate->target
  322.      */
  323.     cairo_surface_destroy (gstate->parent_target);
  324.     gstate->parent_target = gstate->target;
  325.  
  326.     /* Now set up our new target; we overwrite gstate->target directly,
  327.      * since its ref is now owned by gstate->parent_target */
  328.     gstate->target = cairo_surface_reference (child);
  329.     gstate->is_identity &= _cairo_matrix_is_identity (&child->device_transform);
  330.     cairo_list_move (&gstate->device_transform_observer.link,
  331.                      &gstate->target->device_transform_observers);
  332.  
  333.     /* The clip is in surface backend coordinates for the previous target;
  334.      * translate it into the child's backend coordinates. */
  335.     cairo_matrix_init_translate (&matrix,
  336.                                  child->device_transform.x0 - gstate->parent_target->device_transform.x0,
  337.                                  child->device_transform.y0 - gstate->parent_target->device_transform.y0);
  338.     _cairo_clip_reset (&gstate->clip);
  339.     return _cairo_clip_init_copy_transformed (&gstate->clip,
  340.                                               &gstate->next->clip,
  341.                                               &matrix);
  342. }
  343.  
  344. /**
  345.  * _cairo_gstate_is_redirected
  346.  * @gstate: a #cairo_gstate_t
  347.  *
  348.  * This space left intentionally blank.
  349.  *
  350.  * Return value: %TRUE if the gstate is redirected to a target
  351.  * different than the original, %FALSE otherwise.
  352.  **/
  353. cairo_bool_t
  354. _cairo_gstate_is_redirected (cairo_gstate_t *gstate)
  355. {
  356.     return (gstate->target != gstate->original_target);
  357. }
  358.  
  359. /**
  360.  * _cairo_gstate_get_target:
  361.  * @gstate: a #cairo_gstate_t
  362.  *
  363.  * Return the current drawing target; if drawing is not redirected,
  364.  * this will be the same as _cairo_gstate_get_original_target().
  365.  *
  366.  * Return value: the current target surface
  367.  **/
  368. cairo_surface_t *
  369. _cairo_gstate_get_target (cairo_gstate_t *gstate)
  370. {
  371.     return gstate->target;
  372. }
  373.  
  374. /**
  375.  * _cairo_gstate_get_parent_target:
  376.  * @gstate: a #cairo_gstate_t
  377.  *
  378.  * Return the parent surface of the current drawing target surface;
  379.  * if this particular gstate isn't a redirect gstate, this will return %NULL.
  380.  **/
  381. cairo_surface_t *
  382. _cairo_gstate_get_parent_target (cairo_gstate_t *gstate)
  383. {
  384.     return gstate->parent_target;
  385. }
  386.  
  387. /**
  388.  * _cairo_gstate_get_original_target:
  389.  * @gstate: a #cairo_gstate_t
  390.  *
  391.  * Return the original target with which @gstate was created. This
  392.  * function always returns the original target independent of any
  393.  * child target that may have been set with
  394.  * _cairo_gstate_redirect_target.
  395.  *
  396.  * Return value: the original target surface
  397.  **/
  398. cairo_surface_t *
  399. _cairo_gstate_get_original_target (cairo_gstate_t *gstate)
  400. {
  401.     return gstate->original_target;
  402. }
  403.  
  404. /**
  405.  * _cairo_gstate_get_clip:
  406.  * @gstate: a #cairo_gstate_t
  407.  *
  408.  * This space left intentionally blank.
  409.  *
  410.  * Return value: a pointer to the gstate's #cairo_clip_t structure.
  411.  */
  412. cairo_clip_t *
  413. _cairo_gstate_get_clip (cairo_gstate_t *gstate)
  414. {
  415.     return &gstate->clip;
  416. }
  417.  
  418. cairo_status_t
  419. _cairo_gstate_set_source (cairo_gstate_t  *gstate,
  420.                           cairo_pattern_t *source)
  421. {
  422.     if (source->status)
  423.         return source->status;
  424.  
  425.     source = cairo_pattern_reference (source);
  426.     cairo_pattern_destroy (gstate->source);
  427.     gstate->source = source;
  428.     gstate->source_ctm_inverse = gstate->ctm_inverse;
  429.  
  430.     return CAIRO_STATUS_SUCCESS;
  431. }
  432.  
  433. cairo_pattern_t *
  434. _cairo_gstate_get_source (cairo_gstate_t *gstate)
  435. {
  436.     if (gstate->source == &_cairo_pattern_black.base) {
  437.         /* do not expose the static object to the user */
  438.         gstate->source = _cairo_pattern_create_solid (CAIRO_COLOR_BLACK);
  439.     }
  440.  
  441.     return gstate->source;
  442. }
  443.  
  444. cairo_status_t
  445. _cairo_gstate_set_operator (cairo_gstate_t *gstate, cairo_operator_t op)
  446. {
  447.     gstate->op = op;
  448.  
  449.     return CAIRO_STATUS_SUCCESS;
  450. }
  451.  
  452. cairo_operator_t
  453. _cairo_gstate_get_operator (cairo_gstate_t *gstate)
  454. {
  455.     return gstate->op;
  456. }
  457.  
  458. cairo_status_t
  459. _cairo_gstate_set_tolerance (cairo_gstate_t *gstate, double tolerance)
  460. {
  461.     gstate->tolerance = tolerance;
  462.  
  463.     return CAIRO_STATUS_SUCCESS;
  464. }
  465.  
  466. double
  467. _cairo_gstate_get_tolerance (cairo_gstate_t *gstate)
  468. {
  469.     return gstate->tolerance;
  470. }
  471.  
  472. cairo_status_t
  473. _cairo_gstate_set_fill_rule (cairo_gstate_t *gstate, cairo_fill_rule_t fill_rule)
  474. {
  475.     gstate->fill_rule = fill_rule;
  476.  
  477.     return CAIRO_STATUS_SUCCESS;
  478. }
  479.  
  480. cairo_fill_rule_t
  481. _cairo_gstate_get_fill_rule (cairo_gstate_t *gstate)
  482. {
  483.     return gstate->fill_rule;
  484. }
  485.  
  486. cairo_status_t
  487. _cairo_gstate_set_line_width (cairo_gstate_t *gstate, double width)
  488. {
  489.     gstate->stroke_style.line_width = width;
  490.  
  491.     return CAIRO_STATUS_SUCCESS;
  492. }
  493.  
  494. double
  495. _cairo_gstate_get_line_width (cairo_gstate_t *gstate)
  496. {
  497.     return gstate->stroke_style.line_width;
  498. }
  499.  
  500. cairo_status_t
  501. _cairo_gstate_set_line_cap (cairo_gstate_t *gstate, cairo_line_cap_t line_cap)
  502. {
  503.     gstate->stroke_style.line_cap = line_cap;
  504.  
  505.     return CAIRO_STATUS_SUCCESS;
  506. }
  507.  
  508. cairo_line_cap_t
  509. _cairo_gstate_get_line_cap (cairo_gstate_t *gstate)
  510. {
  511.     return gstate->stroke_style.line_cap;
  512. }
  513.  
  514. cairo_status_t
  515. _cairo_gstate_set_line_join (cairo_gstate_t *gstate, cairo_line_join_t line_join)
  516. {
  517.     gstate->stroke_style.line_join = line_join;
  518.  
  519.     return CAIRO_STATUS_SUCCESS;
  520. }
  521.  
  522. cairo_line_join_t
  523. _cairo_gstate_get_line_join (cairo_gstate_t *gstate)
  524. {
  525.     return gstate->stroke_style.line_join;
  526. }
  527.  
  528. cairo_status_t
  529. _cairo_gstate_set_dash (cairo_gstate_t *gstate, const double *dash, int num_dashes, double offset)
  530. {
  531.     unsigned int i;
  532.     double dash_total;
  533.  
  534.     if (gstate->stroke_style.dash)
  535.         free (gstate->stroke_style.dash);
  536.  
  537.     gstate->stroke_style.num_dashes = num_dashes;
  538.  
  539.     if (gstate->stroke_style.num_dashes == 0) {
  540.         gstate->stroke_style.dash = NULL;
  541.         gstate->stroke_style.dash_offset = 0.0;
  542.         return CAIRO_STATUS_SUCCESS;
  543.     }
  544.  
  545.     gstate->stroke_style.dash = _cairo_malloc_ab (gstate->stroke_style.num_dashes, sizeof (double));
  546.     if (unlikely (gstate->stroke_style.dash == NULL)) {
  547.         gstate->stroke_style.num_dashes = 0;
  548.         return _cairo_error (CAIRO_STATUS_NO_MEMORY);
  549.     }
  550.  
  551.     memcpy (gstate->stroke_style.dash, dash, gstate->stroke_style.num_dashes * sizeof (double));
  552.  
  553.     dash_total = 0.0;
  554.     for (i = 0; i < gstate->stroke_style.num_dashes; i++) {
  555.         if (gstate->stroke_style.dash[i] < 0)
  556.             return _cairo_error (CAIRO_STATUS_INVALID_DASH);
  557.  
  558.         dash_total += gstate->stroke_style.dash[i];
  559.     }
  560.  
  561.     if (dash_total == 0.0)
  562.         return _cairo_error (CAIRO_STATUS_INVALID_DASH);
  563.  
  564.     /* An odd dash value indicate symmetric repeating, so the total
  565.      * is twice as long. */
  566.     if (gstate->stroke_style.num_dashes & 1)
  567.         dash_total *= 2;
  568.  
  569.     /* The dashing code doesn't like a negative offset or a big positive
  570.      * offset, so we compute an equivalent offset which is guaranteed to be
  571.      * positive and less than twice the pattern length. */
  572.     offset = fmod (offset, dash_total);
  573.     if (offset < 0.0)
  574.         offset += dash_total;
  575.     if (offset <= 0.0)          /* Take care of -0 */
  576.         offset = 0.0;
  577.     gstate->stroke_style.dash_offset = offset;
  578.  
  579.     return CAIRO_STATUS_SUCCESS;
  580. }
  581.  
  582. void
  583. _cairo_gstate_get_dash (cairo_gstate_t *gstate,
  584.                         double         *dashes,
  585.                         int            *num_dashes,
  586.                         double         *offset)
  587. {
  588.     if (dashes) {
  589.         memcpy (dashes,
  590.                 gstate->stroke_style.dash,
  591.                 sizeof (double) * gstate->stroke_style.num_dashes);
  592.     }
  593.  
  594.     if (num_dashes)
  595.         *num_dashes = gstate->stroke_style.num_dashes;
  596.  
  597.     if (offset)
  598.         *offset = gstate->stroke_style.dash_offset;
  599. }
  600.  
  601. cairo_status_t
  602. _cairo_gstate_set_miter_limit (cairo_gstate_t *gstate, double limit)
  603. {
  604.     gstate->stroke_style.miter_limit = limit;
  605.  
  606.     return CAIRO_STATUS_SUCCESS;
  607. }
  608.  
  609. double
  610. _cairo_gstate_get_miter_limit (cairo_gstate_t *gstate)
  611. {
  612.     return gstate->stroke_style.miter_limit;
  613. }
  614.  
  615. void
  616. _cairo_gstate_get_matrix (cairo_gstate_t *gstate, cairo_matrix_t *matrix)
  617. {
  618.     *matrix = gstate->ctm;
  619. }
  620.  
  621. cairo_status_t
  622. _cairo_gstate_translate (cairo_gstate_t *gstate, double tx, double ty)
  623. {
  624.     cairo_matrix_t tmp;
  625.  
  626.     if (! ISFINITE (tx) || ! ISFINITE (ty))
  627.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  628.  
  629.     _cairo_gstate_unset_scaled_font (gstate);
  630.  
  631.     cairo_matrix_init_translate (&tmp, tx, ty);
  632.     cairo_matrix_multiply (&gstate->ctm, &tmp, &gstate->ctm);
  633.     gstate->is_identity = FALSE;
  634.  
  635.     /* paranoid check against gradual numerical instability */
  636.     if (! _cairo_matrix_is_invertible (&gstate->ctm))
  637.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  638.  
  639.     cairo_matrix_init_translate (&tmp, -tx, -ty);
  640.     cairo_matrix_multiply (&gstate->ctm_inverse, &gstate->ctm_inverse, &tmp);
  641.  
  642.     return CAIRO_STATUS_SUCCESS;
  643. }
  644.  
  645. cairo_status_t
  646. _cairo_gstate_scale (cairo_gstate_t *gstate, double sx, double sy)
  647. {
  648.     cairo_matrix_t tmp;
  649.  
  650.     if (sx * sy == 0.) /* either sx or sy is 0, or det == 0 due to underflow */
  651.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  652.     if (! ISFINITE (sx) || ! ISFINITE (sy))
  653.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  654.  
  655.     _cairo_gstate_unset_scaled_font (gstate);
  656.  
  657.     cairo_matrix_init_scale (&tmp, sx, sy);
  658.     cairo_matrix_multiply (&gstate->ctm, &tmp, &gstate->ctm);
  659.     gstate->is_identity = FALSE;
  660.  
  661.     /* paranoid check against gradual numerical instability */
  662.     if (! _cairo_matrix_is_invertible (&gstate->ctm))
  663.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  664.  
  665.     cairo_matrix_init_scale (&tmp, 1/sx, 1/sy);
  666.     cairo_matrix_multiply (&gstate->ctm_inverse, &gstate->ctm_inverse, &tmp);
  667.  
  668.     return CAIRO_STATUS_SUCCESS;
  669. }
  670.  
  671. cairo_status_t
  672. _cairo_gstate_rotate (cairo_gstate_t *gstate, double angle)
  673. {
  674.     cairo_matrix_t tmp;
  675.  
  676.     if (angle == 0.)
  677.         return CAIRO_STATUS_SUCCESS;
  678.  
  679.     if (! ISFINITE (angle))
  680.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  681.  
  682.     _cairo_gstate_unset_scaled_font (gstate);
  683.  
  684.     cairo_matrix_init_rotate (&tmp, angle);
  685.     cairo_matrix_multiply (&gstate->ctm, &tmp, &gstate->ctm);
  686.     gstate->is_identity = FALSE;
  687.  
  688.     /* paranoid check against gradual numerical instability */
  689.     if (! _cairo_matrix_is_invertible (&gstate->ctm))
  690.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  691.  
  692.     cairo_matrix_init_rotate (&tmp, -angle);
  693.     cairo_matrix_multiply (&gstate->ctm_inverse, &gstate->ctm_inverse, &tmp);
  694.  
  695.     return CAIRO_STATUS_SUCCESS;
  696. }
  697.  
  698. cairo_status_t
  699. _cairo_gstate_transform (cairo_gstate_t       *gstate,
  700.                          const cairo_matrix_t *matrix)
  701. {
  702.     cairo_matrix_t tmp;
  703.     cairo_status_t status;
  704.  
  705.     if (! _cairo_matrix_is_invertible (matrix))
  706.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  707.  
  708.     if (_cairo_matrix_is_identity (matrix))
  709.         return CAIRO_STATUS_SUCCESS;
  710.  
  711.     tmp = *matrix;
  712.     status = cairo_matrix_invert (&tmp);
  713.     if (unlikely (status))
  714.         return status;
  715.  
  716.     _cairo_gstate_unset_scaled_font (gstate);
  717.  
  718.     cairo_matrix_multiply (&gstate->ctm, matrix, &gstate->ctm);
  719.     cairo_matrix_multiply (&gstate->ctm_inverse, &gstate->ctm_inverse, &tmp);
  720.     gstate->is_identity = FALSE;
  721.  
  722.     /* paranoid check against gradual numerical instability */
  723.     if (! _cairo_matrix_is_invertible (&gstate->ctm))
  724.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  725.  
  726.     return CAIRO_STATUS_SUCCESS;
  727. }
  728.  
  729. cairo_status_t
  730. _cairo_gstate_set_matrix (cairo_gstate_t       *gstate,
  731.                           const cairo_matrix_t *matrix)
  732. {
  733.     cairo_status_t status;
  734.  
  735.     if (memcmp (matrix, &gstate->ctm, sizeof (cairo_matrix_t)) == 0)
  736.         return CAIRO_STATUS_SUCCESS;
  737.  
  738.     if (! _cairo_matrix_is_invertible (matrix))
  739.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  740.  
  741.     if (_cairo_matrix_is_identity (matrix)) {
  742.         _cairo_gstate_identity_matrix (gstate);
  743.         return CAIRO_STATUS_SUCCESS;
  744.     }
  745.  
  746.     _cairo_gstate_unset_scaled_font (gstate);
  747.  
  748.     gstate->ctm = *matrix;
  749.     gstate->ctm_inverse = *matrix;
  750.     status = cairo_matrix_invert (&gstate->ctm_inverse);
  751.     assert (status == CAIRO_STATUS_SUCCESS);
  752.     gstate->is_identity = FALSE;
  753.  
  754.     return CAIRO_STATUS_SUCCESS;
  755. }
  756.  
  757. void
  758. _cairo_gstate_identity_matrix (cairo_gstate_t *gstate)
  759. {
  760.     if (_cairo_matrix_is_identity (&gstate->ctm))
  761.         return;
  762.  
  763.     _cairo_gstate_unset_scaled_font (gstate);
  764.  
  765.     cairo_matrix_init_identity (&gstate->ctm);
  766.     cairo_matrix_init_identity (&gstate->ctm_inverse);
  767.     gstate->is_identity = _cairo_matrix_is_identity (&gstate->target->device_transform);
  768. }
  769.  
  770. void
  771. _cairo_gstate_user_to_device (cairo_gstate_t *gstate, double *x, double *y)
  772. {
  773.     cairo_matrix_transform_point (&gstate->ctm, x, y);
  774. }
  775.  
  776. void
  777. _cairo_gstate_user_to_device_distance (cairo_gstate_t *gstate,
  778.                                        double *dx, double *dy)
  779. {
  780.     cairo_matrix_transform_distance (&gstate->ctm, dx, dy);
  781. }
  782.  
  783. void
  784. _cairo_gstate_device_to_user (cairo_gstate_t *gstate, double *x, double *y)
  785. {
  786.     cairo_matrix_transform_point (&gstate->ctm_inverse, x, y);
  787. }
  788.  
  789. void
  790. _cairo_gstate_device_to_user_distance (cairo_gstate_t *gstate,
  791.                                        double *dx, double *dy)
  792. {
  793.     cairo_matrix_transform_distance (&gstate->ctm_inverse, dx, dy);
  794. }
  795.  
  796. void
  797. _do_cairo_gstate_user_to_backend (cairo_gstate_t *gstate, double *x, double *y)
  798. {
  799.     cairo_matrix_transform_point (&gstate->ctm, x, y);
  800.     cairo_matrix_transform_point (&gstate->target->device_transform, x, y);
  801. }
  802.  
  803. void
  804. _do_cairo_gstate_backend_to_user (cairo_gstate_t *gstate, double *x, double *y)
  805. {
  806.     cairo_matrix_transform_point (&gstate->target->device_transform_inverse, x, y);
  807.     cairo_matrix_transform_point (&gstate->ctm_inverse, x, y);
  808. }
  809.  
  810. void
  811. _cairo_gstate_backend_to_user_rectangle (cairo_gstate_t *gstate,
  812.                                          double *x1, double *y1,
  813.                                          double *x2, double *y2,
  814.                                          cairo_bool_t *is_tight)
  815. {
  816.     cairo_matrix_t matrix_inverse;
  817.  
  818.     cairo_matrix_multiply (&matrix_inverse,
  819.                            &gstate->target->device_transform_inverse,
  820.                            &gstate->ctm_inverse);
  821.     _cairo_matrix_transform_bounding_box (&matrix_inverse,
  822.                                           x1, y1, x2, y2, is_tight);
  823. }
  824.  
  825. /* XXX: NYI
  826. cairo_status_t
  827. _cairo_gstate_stroke_to_path (cairo_gstate_t *gstate)
  828. {
  829.     cairo_status_t status;
  830.  
  831.     _cairo_pen_init (&gstate);
  832.     return CAIRO_STATUS_SUCCESS;
  833. }
  834. */
  835.  
  836. void
  837. _cairo_gstate_path_extents (cairo_gstate_t     *gstate,
  838.                             cairo_path_fixed_t *path,
  839.                             double *x1, double *y1,
  840.                             double *x2, double *y2)
  841. {
  842.     cairo_box_t box;
  843.     double px1, py1, px2, py2;
  844.  
  845.     if (_cairo_path_fixed_extents (path, &box)) {
  846.         px1 = _cairo_fixed_to_double (box.p1.x);
  847.         py1 = _cairo_fixed_to_double (box.p1.y);
  848.         px2 = _cairo_fixed_to_double (box.p2.x);
  849.         py2 = _cairo_fixed_to_double (box.p2.y);
  850.  
  851.         _cairo_gstate_backend_to_user_rectangle (gstate,
  852.                                                  &px1, &py1, &px2, &py2,
  853.                                                  NULL);
  854.     } else {
  855.         px1 = 0.0;
  856.         py1 = 0.0;
  857.         px2 = 0.0;
  858.         py2 = 0.0;
  859.     }
  860.  
  861.     if (x1)
  862.         *x1 = px1;
  863.     if (y1)
  864.         *y1 = py1;
  865.     if (x2)
  866.         *x2 = px2;
  867.     if (y2)
  868.         *y2 = py2;
  869. }
  870.  
  871. static void
  872. _cairo_gstate_copy_pattern (cairo_pattern_t *pattern,
  873.                             const cairo_pattern_t *original)
  874. {
  875.     /* First check if the we can replace the original with a much simpler
  876.      * pattern. For example, gradients that are uniform or just have a single
  877.      * stop can sometimes be replaced with a solid.
  878.      */
  879.  
  880.     if (_cairo_pattern_is_clear (original)) {
  881.         _cairo_pattern_init_solid ((cairo_solid_pattern_t *) pattern,
  882.                                    CAIRO_COLOR_TRANSPARENT);
  883.         return;
  884.     }
  885.  
  886.     if (original->type == CAIRO_PATTERN_TYPE_LINEAR ||
  887.         original->type == CAIRO_PATTERN_TYPE_RADIAL)
  888.     {
  889.         cairo_color_t color;
  890.         if (_cairo_gradient_pattern_is_solid ((cairo_gradient_pattern_t *) original,
  891.                                               NULL,
  892.                                               &color))
  893.         {
  894.             _cairo_pattern_init_solid ((cairo_solid_pattern_t *) pattern,
  895.                                        &color);
  896.             return;
  897.         }
  898.     }
  899.  
  900.     _cairo_pattern_init_static_copy (pattern, original);
  901. }
  902.  
  903. static void
  904. _cairo_gstate_copy_transformed_pattern (cairo_gstate_t  *gstate,
  905.                                         cairo_pattern_t *pattern,
  906.                                         const cairo_pattern_t *original,
  907.                                         const cairo_matrix_t  *ctm_inverse)
  908. {
  909.     _cairo_gstate_copy_pattern (pattern, original);
  910.  
  911.     /* apply device_transform first so that it is transformed by ctm_inverse */
  912.     if (original->type == CAIRO_PATTERN_TYPE_SURFACE) {
  913.         cairo_surface_pattern_t *surface_pattern;
  914.         cairo_surface_t *surface;
  915.  
  916.         surface_pattern = (cairo_surface_pattern_t *) original;
  917.         surface = surface_pattern->surface;
  918.  
  919.         if (_cairo_surface_has_device_transform (surface))
  920.             _cairo_pattern_transform (pattern, &surface->device_transform);
  921.     }
  922.  
  923.     if (! _cairo_matrix_is_identity (ctm_inverse))
  924.         _cairo_pattern_transform (pattern, ctm_inverse);
  925.  
  926.     if (_cairo_surface_has_device_transform (gstate->target)) {
  927.         _cairo_pattern_transform (pattern,
  928.                                   &gstate->target->device_transform_inverse);
  929.     }
  930. }
  931.  
  932. static void
  933. _cairo_gstate_copy_transformed_source (cairo_gstate_t   *gstate,
  934.                                        cairo_pattern_t  *pattern)
  935. {
  936.     _cairo_gstate_copy_transformed_pattern (gstate, pattern,
  937.                                             gstate->source,
  938.                                             &gstate->source_ctm_inverse);
  939. }
  940.  
  941. static void
  942. _cairo_gstate_copy_transformed_mask (cairo_gstate_t   *gstate,
  943.                                      cairo_pattern_t  *pattern,
  944.                                      cairo_pattern_t  *mask)
  945. {
  946.     _cairo_gstate_copy_transformed_pattern (gstate, pattern,
  947.                                             mask,
  948.                                             &gstate->ctm_inverse);
  949. }
  950.  
  951. /* We need to take a copy of the clip so that the lower layers may modify it
  952.  * by, perhaps, intersecting it with the operation extents and other paths.
  953.  */
  954. #define _gstate_get_clip(G, C) _cairo_clip_init_copy ((C), &(G)->clip)
  955.  
  956. static cairo_bool_t
  957. _clipped (cairo_gstate_t *gstate)
  958. {
  959.     cairo_rectangle_int_t extents;
  960.  
  961.     if (gstate->clip.all_clipped)
  962.         return TRUE;
  963.  
  964.     /* XXX consider applying a surface clip? */
  965.  
  966.     if (gstate->clip.path == NULL)
  967.         return FALSE;
  968.  
  969.     if (_cairo_surface_get_extents (gstate->target, &extents)) {
  970.         if (extents.width == 0 || extents.height == 0)
  971.             return TRUE;
  972.  
  973.         if (! _cairo_rectangle_intersect (&extents,
  974.                                           &gstate->clip.path->extents))
  975.         {
  976.             return TRUE;
  977.         }
  978.     }
  979.  
  980.     /* perform a simple query to exclude trivial all-clipped cases */
  981.     return _cairo_clip_get_region (&gstate->clip, NULL) == CAIRO_INT_STATUS_NOTHING_TO_DO;
  982. }
  983.  
  984. static cairo_operator_t
  985. _reduce_op (cairo_gstate_t *gstate)
  986. {
  987.     cairo_operator_t op;
  988.     const cairo_pattern_t *pattern;
  989.  
  990.     op = gstate->op;
  991.     if (op != CAIRO_OPERATOR_SOURCE)
  992.         return op;
  993.  
  994.     pattern = gstate->source;
  995.     if (pattern->type == CAIRO_PATTERN_TYPE_SOLID) {
  996.         const cairo_solid_pattern_t *solid = (cairo_solid_pattern_t *) pattern;
  997.         if (solid->color.alpha_short <= 0x00ff) {
  998.             op = CAIRO_OPERATOR_CLEAR;
  999.         } else if ((gstate->target->content & CAIRO_CONTENT_ALPHA) == 0) {
  1000.             if ((solid->color.red_short |
  1001.                  solid->color.green_short |
  1002.                  solid->color.blue_short) <= 0x00ff)
  1003.             {
  1004.                 op = CAIRO_OPERATOR_CLEAR;
  1005.             }
  1006.         }
  1007.     } else if (pattern->type == CAIRO_PATTERN_TYPE_SURFACE) {
  1008.         const cairo_surface_pattern_t *surface = (cairo_surface_pattern_t *) pattern;
  1009.         if (surface->surface->is_clear &&
  1010.             surface->surface->content & CAIRO_CONTENT_ALPHA)
  1011.         {
  1012.             op = CAIRO_OPERATOR_CLEAR;
  1013.         }
  1014.     } else {
  1015.         const cairo_gradient_pattern_t *gradient = (cairo_gradient_pattern_t *) pattern;
  1016.         if (gradient->n_stops == 0)
  1017.             op = CAIRO_OPERATOR_CLEAR;
  1018.     }
  1019.  
  1020.     return op;
  1021. }
  1022.  
  1023. cairo_status_t
  1024. _cairo_gstate_paint (cairo_gstate_t *gstate)
  1025. {
  1026.     cairo_pattern_union_t source_pattern;
  1027.     const cairo_pattern_t *pattern;
  1028.     cairo_clip_t clip;
  1029.     cairo_status_t status;
  1030.     cairo_operator_t op;
  1031.  
  1032.     if (unlikely (gstate->source->status))
  1033.         return gstate->source->status;
  1034.  
  1035.     if (gstate->op == CAIRO_OPERATOR_DEST)
  1036.         return CAIRO_STATUS_SUCCESS;
  1037.  
  1038.     if (_clipped (gstate))
  1039.         return CAIRO_STATUS_SUCCESS;
  1040.  
  1041.     op = _reduce_op (gstate);
  1042.     if (op == CAIRO_OPERATOR_CLEAR) {
  1043.         pattern = &_cairo_pattern_clear.base;
  1044.     } else {
  1045.         _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base);
  1046.         pattern = &source_pattern.base;
  1047.     }
  1048.  
  1049.     status = _cairo_surface_paint (gstate->target,
  1050.                                    op, pattern,
  1051.                                    _gstate_get_clip (gstate, &clip));
  1052.     _cairo_clip_fini (&clip);
  1053.  
  1054.     return status;
  1055. }
  1056.  
  1057. cairo_status_t
  1058. _cairo_gstate_mask (cairo_gstate_t  *gstate,
  1059.                     cairo_pattern_t *mask)
  1060. {
  1061.     cairo_pattern_union_t source_pattern, mask_pattern;
  1062.     const cairo_pattern_t *source;
  1063.     cairo_operator_t op;
  1064.     cairo_clip_t clip;
  1065.     cairo_status_t status;
  1066.  
  1067.     if (unlikely (mask->status))
  1068.         return mask->status;
  1069.  
  1070.     if (unlikely (gstate->source->status))
  1071.         return gstate->source->status;
  1072.  
  1073.     if (gstate->op == CAIRO_OPERATOR_DEST)
  1074.         return CAIRO_STATUS_SUCCESS;
  1075.  
  1076.     if (_clipped (gstate))
  1077.         return CAIRO_STATUS_SUCCESS;
  1078.  
  1079.     if (_cairo_pattern_is_opaque (mask, NULL))
  1080.         return _cairo_gstate_paint (gstate);
  1081.  
  1082.     if (_cairo_pattern_is_clear (mask) &&
  1083.         _cairo_operator_bounded_by_mask (gstate->op))
  1084.     {
  1085.         return CAIRO_STATUS_SUCCESS;
  1086.     }
  1087.  
  1088.     op = _reduce_op (gstate);
  1089.     if (op == CAIRO_OPERATOR_CLEAR) {
  1090.         source = &_cairo_pattern_clear.base;
  1091.     } else {
  1092.         _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base);
  1093.         source = &source_pattern.base;
  1094.     }
  1095.     _cairo_gstate_copy_transformed_mask (gstate, &mask_pattern.base, mask);
  1096.  
  1097.     if (source->type == CAIRO_PATTERN_TYPE_SOLID &&
  1098.         mask_pattern.type == CAIRO_PATTERN_TYPE_SOLID &&
  1099.         _cairo_operator_bounded_by_source (op))
  1100.     {
  1101.         const cairo_solid_pattern_t *solid = (cairo_solid_pattern_t *) source;
  1102.         cairo_color_t combined;
  1103.  
  1104.         if (mask_pattern.base.has_component_alpha) {
  1105. #define M(R, A, B, c) R.c = A.c * B.c
  1106.             M(combined, solid->color, mask_pattern.solid.color, red);
  1107.             M(combined, solid->color, mask_pattern.solid.color, green);
  1108.             M(combined, solid->color, mask_pattern.solid.color, blue);
  1109.             M(combined, solid->color, mask_pattern.solid.color, alpha);
  1110. #undef M
  1111.         } else {
  1112.             combined = solid->color;
  1113.             _cairo_color_multiply_alpha (&combined, mask_pattern.solid.color.alpha);
  1114.         }
  1115.  
  1116.         _cairo_pattern_init_solid (&source_pattern.solid, &combined);
  1117.  
  1118.         status = _cairo_surface_paint (gstate->target, op,
  1119.                                        &source_pattern.base,
  1120.                                        _gstate_get_clip (gstate, &clip));
  1121.     }
  1122.     else
  1123.     {
  1124.         status = _cairo_surface_mask (gstate->target, op,
  1125.                                       source,
  1126.                                       &mask_pattern.base,
  1127.                                       _gstate_get_clip (gstate, &clip));
  1128.     }
  1129.     _cairo_clip_fini (&clip);
  1130.  
  1131.     return status;
  1132. }
  1133.  
  1134. cairo_status_t
  1135. _cairo_gstate_stroke (cairo_gstate_t *gstate, cairo_path_fixed_t *path)
  1136. {
  1137.     cairo_pattern_union_t source_pattern;
  1138.     cairo_stroke_style_t style;
  1139.     double dash[2];
  1140.     cairo_clip_t clip;
  1141.     cairo_status_t status;
  1142.  
  1143.     if (unlikely (gstate->source->status))
  1144.         return gstate->source->status;
  1145.  
  1146.     if (gstate->op == CAIRO_OPERATOR_DEST)
  1147.         return CAIRO_STATUS_SUCCESS;
  1148.  
  1149.     if (gstate->stroke_style.line_width <= 0.0)
  1150.         return CAIRO_STATUS_SUCCESS;
  1151.  
  1152.     if (_clipped (gstate))
  1153.         return CAIRO_STATUS_SUCCESS;
  1154.  
  1155.     memcpy (&style, &gstate->stroke_style, sizeof (gstate->stroke_style));
  1156.     if (_cairo_stroke_style_dash_can_approximate (&gstate->stroke_style, &gstate->ctm, gstate->tolerance)) {
  1157.         style.dash = dash;
  1158.         _cairo_stroke_style_dash_approximate (&gstate->stroke_style, &gstate->ctm, gstate->tolerance,
  1159.                                               &style.dash_offset,
  1160.                                               style.dash,
  1161.                                               &style.num_dashes);
  1162.     }
  1163.  
  1164.     _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base);
  1165.  
  1166.     status = _cairo_surface_stroke (gstate->target,
  1167.                                     gstate->op,
  1168.                                     &source_pattern.base,
  1169.                                     path,
  1170.                                     &style,
  1171.                                     &gstate->ctm,
  1172.                                     &gstate->ctm_inverse,
  1173.                                     gstate->tolerance,
  1174.                                     gstate->antialias,
  1175.                                     _gstate_get_clip (gstate, &clip));
  1176.     _cairo_clip_fini (&clip);
  1177.  
  1178.     return status;
  1179. }
  1180.  
  1181. cairo_status_t
  1182. _cairo_gstate_in_stroke (cairo_gstate_t     *gstate,
  1183.                          cairo_path_fixed_t *path,
  1184.                          double              x,
  1185.                          double              y,
  1186.                          cairo_bool_t       *inside_ret)
  1187. {
  1188.     cairo_status_t status;
  1189.     cairo_rectangle_int_t extents;
  1190.     cairo_box_t limit;
  1191.     cairo_traps_t traps;
  1192.  
  1193.     if (gstate->stroke_style.line_width <= 0.0) {
  1194.         *inside_ret = FALSE;
  1195.         return CAIRO_STATUS_SUCCESS;
  1196.     }
  1197.  
  1198.     _cairo_gstate_user_to_backend (gstate, &x, &y);
  1199.  
  1200.     /* Before we perform the expensive stroke analysis,
  1201.      * check whether the point is within the extents of the path.
  1202.      */
  1203.     _cairo_path_fixed_approximate_stroke_extents (path,
  1204.                                                   &gstate->stroke_style,
  1205.                                                   &gstate->ctm,
  1206.                                                   &extents);
  1207.     if (x < extents.x || x > extents.x + extents.width ||
  1208.         y < extents.y || y > extents.y + extents.height)
  1209.     {
  1210.         *inside_ret = FALSE;
  1211.         return CAIRO_STATUS_SUCCESS;
  1212.     }
  1213.  
  1214.     limit.p1.x = _cairo_fixed_from_double (x) - 1;
  1215.     limit.p1.y = _cairo_fixed_from_double (y) - 1;
  1216.     limit.p2.x = limit.p1.x + 2;
  1217.     limit.p2.y = limit.p1.y + 2;
  1218.  
  1219.     _cairo_traps_init (&traps);
  1220.     _cairo_traps_limit (&traps, &limit, 1);
  1221.  
  1222.     status = _cairo_path_fixed_stroke_to_traps (path,
  1223.                                                 &gstate->stroke_style,
  1224.                                                 &gstate->ctm,
  1225.                                                 &gstate->ctm_inverse,
  1226.                                                 gstate->tolerance,
  1227.                                                 &traps);
  1228.     if (unlikely (status))
  1229.         goto BAIL;
  1230.  
  1231.     *inside_ret = _cairo_traps_contain (&traps, x, y);
  1232.  
  1233. BAIL:
  1234.     _cairo_traps_fini (&traps);
  1235.  
  1236.     return status;
  1237. }
  1238.  
  1239. cairo_status_t
  1240. _cairo_gstate_fill (cairo_gstate_t *gstate, cairo_path_fixed_t *path)
  1241. {
  1242.     cairo_clip_t clip;
  1243.     cairo_status_t status;
  1244.  
  1245.     if (unlikely (gstate->source->status))
  1246.         return gstate->source->status;
  1247.  
  1248.     if (gstate->op == CAIRO_OPERATOR_DEST)
  1249.         return CAIRO_STATUS_SUCCESS;
  1250.  
  1251.     if (_clipped (gstate))
  1252.         return CAIRO_STATUS_SUCCESS;
  1253.  
  1254.     if (_cairo_path_fixed_fill_is_empty (path)) {
  1255.         if (_cairo_operator_bounded_by_mask (gstate->op))
  1256.             return CAIRO_STATUS_SUCCESS;
  1257.  
  1258.         status = _cairo_surface_paint (gstate->target,
  1259.                                        CAIRO_OPERATOR_CLEAR,
  1260.                                        &_cairo_pattern_clear.base,
  1261.                                        _gstate_get_clip (gstate, &clip));
  1262.     } else {
  1263.         cairo_pattern_union_t source_pattern;
  1264.         const cairo_pattern_t *pattern;
  1265.         cairo_operator_t op;
  1266.         cairo_rectangle_int_t extents;
  1267.         cairo_box_t box;
  1268.  
  1269.         op = _reduce_op (gstate);
  1270.         if (op == CAIRO_OPERATOR_CLEAR) {
  1271.             pattern = &_cairo_pattern_clear.base;
  1272.         } else {
  1273.             _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base);
  1274.             pattern = &source_pattern.base;
  1275.         }
  1276.  
  1277.         /* Toolkits often paint the entire background with a fill */
  1278.         if (_cairo_surface_get_extents (gstate->target, &extents) &&
  1279.             _cairo_path_fixed_is_box (path, &box) &&
  1280.             box.p1.x <= _cairo_fixed_from_int (extents.x) &&
  1281.             box.p1.y <= _cairo_fixed_from_int (extents.y) &&
  1282.             box.p2.x >= _cairo_fixed_from_int (extents.x + extents.width) &&
  1283.             box.p2.y >= _cairo_fixed_from_int (extents.y + extents.height))
  1284.         {
  1285.             status = _cairo_surface_paint (gstate->target, op, pattern,
  1286.                                            _gstate_get_clip (gstate, &clip));
  1287.         }
  1288.         else
  1289.         {
  1290.             status = _cairo_surface_fill (gstate->target, op, pattern,
  1291.                                           path,
  1292.                                           gstate->fill_rule,
  1293.                                           gstate->tolerance,
  1294.                                           gstate->antialias,
  1295.                                           _gstate_get_clip (gstate, &clip));
  1296.         }
  1297.     }
  1298.  
  1299.     _cairo_clip_fini (&clip);
  1300.  
  1301.     return status;
  1302. }
  1303.  
  1304. cairo_bool_t
  1305. _cairo_gstate_in_fill (cairo_gstate_t     *gstate,
  1306.                        cairo_path_fixed_t *path,
  1307.                        double              x,
  1308.                        double              y)
  1309. {
  1310.     _cairo_gstate_user_to_backend (gstate, &x, &y);
  1311.  
  1312.     return _cairo_path_fixed_in_fill (path,
  1313.                                       gstate->fill_rule,
  1314.                                       gstate->tolerance,
  1315.                                       x, y);
  1316. }
  1317.  
  1318. cairo_bool_t
  1319. _cairo_gstate_in_clip (cairo_gstate_t     *gstate,
  1320.                        double              x,
  1321.                        double              y)
  1322. {
  1323.     cairo_clip_path_t *clip_path;
  1324.  
  1325.     if (gstate->clip.all_clipped)
  1326.         return FALSE;
  1327.  
  1328.     clip_path = gstate->clip.path;
  1329.     if (clip_path == NULL)
  1330.         return TRUE;
  1331.  
  1332.     _cairo_gstate_user_to_backend (gstate, &x, &y);
  1333.  
  1334.     if (x <  clip_path->extents.x ||
  1335.         x >= clip_path->extents.x + clip_path->extents.width ||
  1336.         y <  clip_path->extents.y ||
  1337.         y >= clip_path->extents.y + clip_path->extents.height)
  1338.     {
  1339.         return FALSE;
  1340.     }
  1341.  
  1342.     do {
  1343.         if (! _cairo_path_fixed_in_fill (&clip_path->path,
  1344.                                          clip_path->fill_rule,
  1345.                                          clip_path->tolerance,
  1346.                                          x, y))
  1347.             return FALSE;
  1348.     } while ((clip_path = clip_path->prev) != NULL);
  1349.  
  1350.     return TRUE;
  1351. }
  1352.  
  1353. cairo_status_t
  1354. _cairo_gstate_copy_page (cairo_gstate_t *gstate)
  1355. {
  1356.     cairo_surface_copy_page (gstate->target);
  1357.     return cairo_surface_status (gstate->target);
  1358. }
  1359.  
  1360. cairo_status_t
  1361. _cairo_gstate_show_page (cairo_gstate_t *gstate)
  1362. {
  1363.     cairo_surface_show_page (gstate->target);
  1364.     return cairo_surface_status (gstate->target);
  1365. }
  1366.  
  1367. static void
  1368. _cairo_gstate_traps_extents_to_user_rectangle (cairo_gstate_t     *gstate,
  1369.                                                cairo_traps_t      *traps,
  1370.                                                double *x1, double *y1,
  1371.                                                double *x2, double *y2)
  1372. {
  1373.     cairo_box_t extents;
  1374.  
  1375.     if (traps->num_traps == 0) {
  1376.         /* no traps, so we actually won't draw anything */
  1377.         if (x1)
  1378.             *x1 = 0.0;
  1379.         if (y1)
  1380.             *y1 = 0.0;
  1381.         if (x2)
  1382.             *x2 = 0.0;
  1383.         if (y2)
  1384.             *y2 = 0.0;
  1385.     } else {
  1386.         double px1, py1, px2, py2;
  1387.  
  1388.         _cairo_traps_extents (traps, &extents);
  1389.  
  1390.         px1 = _cairo_fixed_to_double (extents.p1.x);
  1391.         py1 = _cairo_fixed_to_double (extents.p1.y);
  1392.         px2 = _cairo_fixed_to_double (extents.p2.x);
  1393.         py2 = _cairo_fixed_to_double (extents.p2.y);
  1394.  
  1395.         _cairo_gstate_backend_to_user_rectangle (gstate,
  1396.                                                  &px1, &py1, &px2, &py2,
  1397.                                                  NULL);
  1398.         if (x1)
  1399.             *x1 = px1;
  1400.         if (y1)
  1401.             *y1 = py1;
  1402.         if (x2)
  1403.             *x2 = px2;
  1404.         if (y2)
  1405.             *y2 = py2;
  1406.     }
  1407. }
  1408.  
  1409. cairo_status_t
  1410. _cairo_gstate_stroke_extents (cairo_gstate_t     *gstate,
  1411.                               cairo_path_fixed_t *path,
  1412.                               double *x1, double *y1,
  1413.                               double *x2, double *y2)
  1414. {
  1415.     cairo_status_t status;
  1416.     cairo_traps_t traps;
  1417.  
  1418.     if (gstate->stroke_style.line_width <= 0.0) {
  1419.         if (x1)
  1420.             *x1 = 0.0;
  1421.         if (y1)
  1422.             *y1 = 0.0;
  1423.         if (x2)
  1424.             *x2 = 0.0;
  1425.         if (y2)
  1426.             *y2 = 0.0;
  1427.         return CAIRO_STATUS_SUCCESS;
  1428.     }
  1429.  
  1430.     _cairo_traps_init (&traps);
  1431.  
  1432.     status = _cairo_path_fixed_stroke_to_traps (path,
  1433.                                                 &gstate->stroke_style,
  1434.                                                 &gstate->ctm,
  1435.                                                 &gstate->ctm_inverse,
  1436.                                                 gstate->tolerance,
  1437.                                                 &traps);
  1438.     if (likely (status == CAIRO_STATUS_SUCCESS)) {
  1439.         _cairo_gstate_traps_extents_to_user_rectangle (gstate, &traps,
  1440.                                                        x1, y1, x2, y2);
  1441.     }
  1442.  
  1443.     _cairo_traps_fini (&traps);
  1444.  
  1445.     return status;
  1446. }
  1447.  
  1448. cairo_status_t
  1449. _cairo_gstate_fill_extents (cairo_gstate_t     *gstate,
  1450.                             cairo_path_fixed_t *path,
  1451.                             double *x1, double *y1,
  1452.                             double *x2, double *y2)
  1453. {
  1454.     cairo_status_t status;
  1455.     cairo_traps_t traps;
  1456.  
  1457.     if (path->is_empty_fill) {
  1458.         if (x1)
  1459.             *x1 = 0.0;
  1460.         if (y1)
  1461.             *y1 = 0.0;
  1462.         if (x2)
  1463.             *x2 = 0.0;
  1464.         if (y2)
  1465.             *y2 = 0.0;
  1466.         return CAIRO_STATUS_SUCCESS;
  1467.     }
  1468.  
  1469.     _cairo_traps_init (&traps);
  1470.  
  1471.     status = _cairo_path_fixed_fill_to_traps (path,
  1472.                                               gstate->fill_rule,
  1473.                                               gstate->tolerance,
  1474.                                               &traps);
  1475.     if (likely (status == CAIRO_STATUS_SUCCESS)) {
  1476.         _cairo_gstate_traps_extents_to_user_rectangle (gstate, &traps,
  1477.                                                        x1, y1, x2, y2);
  1478.     }
  1479.  
  1480.     _cairo_traps_fini (&traps);
  1481.  
  1482.     return status;
  1483. }
  1484.  
  1485. cairo_status_t
  1486. _cairo_gstate_reset_clip (cairo_gstate_t *gstate)
  1487. {
  1488.     _cairo_clip_reset (&gstate->clip);
  1489.  
  1490.     return CAIRO_STATUS_SUCCESS;
  1491. }
  1492.  
  1493. cairo_status_t
  1494. _cairo_gstate_clip (cairo_gstate_t *gstate, cairo_path_fixed_t *path)
  1495. {
  1496.     return _cairo_clip_clip (&gstate->clip,
  1497.                              path, gstate->fill_rule,
  1498.                              gstate->tolerance, gstate->antialias);
  1499. }
  1500.  
  1501. static cairo_bool_t
  1502. _cairo_gstate_int_clip_extents (cairo_gstate_t        *gstate,
  1503.                                 cairo_rectangle_int_t *extents)
  1504. {
  1505.     const cairo_rectangle_int_t *clip_extents;
  1506.     cairo_bool_t is_bounded;
  1507.  
  1508.     is_bounded = _cairo_surface_get_extents (gstate->target, extents);
  1509.  
  1510.     clip_extents = _cairo_clip_get_extents (&gstate->clip);
  1511.     if (clip_extents != NULL) {
  1512.         cairo_bool_t is_empty;
  1513.  
  1514.         is_empty = _cairo_rectangle_intersect (extents, clip_extents);
  1515.         is_bounded = TRUE;
  1516.     }
  1517.  
  1518.     return is_bounded;
  1519. }
  1520.  
  1521. cairo_bool_t
  1522. _cairo_gstate_clip_extents (cairo_gstate_t *gstate,
  1523.                             double         *x1,
  1524.                             double         *y1,
  1525.                             double         *x2,
  1526.                             double         *y2)
  1527. {
  1528.     cairo_rectangle_int_t extents;
  1529.     double px1, py1, px2, py2;
  1530.  
  1531.     if (! _cairo_gstate_int_clip_extents (gstate, &extents))
  1532.         return FALSE;
  1533.  
  1534.     px1 = extents.x;
  1535.     py1 = extents.y;
  1536.     px2 = extents.x + (int) extents.width;
  1537.     py2 = extents.y + (int) extents.height;
  1538.  
  1539.     _cairo_gstate_backend_to_user_rectangle (gstate,
  1540.                                              &px1, &py1, &px2, &py2,
  1541.                                              NULL);
  1542.  
  1543.     if (x1)
  1544.         *x1 = px1;
  1545.     if (y1)
  1546.         *y1 = py1;
  1547.     if (x2)
  1548.         *x2 = px2;
  1549.     if (y2)
  1550.         *y2 = py2;
  1551.  
  1552.     return TRUE;
  1553. }
  1554.  
  1555. cairo_rectangle_list_t*
  1556. _cairo_gstate_copy_clip_rectangle_list (cairo_gstate_t *gstate)
  1557. {
  1558.     cairo_clip_t clip;
  1559.     cairo_rectangle_int_t extents;
  1560.     cairo_rectangle_list_t *list;
  1561.  
  1562.     _cairo_clip_init_copy (&clip, &gstate->clip);
  1563.  
  1564.     if (_cairo_surface_get_extents (gstate->target, &extents))
  1565.         _cairo_clip_rectangle (&clip, &extents);
  1566.  
  1567.     list = _cairo_clip_copy_rectangle_list (&clip, gstate);
  1568.     _cairo_clip_fini (&clip);
  1569.  
  1570.     return list;
  1571. }
  1572.  
  1573. static void
  1574. _cairo_gstate_unset_scaled_font (cairo_gstate_t *gstate)
  1575. {
  1576.     if (gstate->scaled_font == NULL)
  1577.         return;
  1578.  
  1579.     if (gstate->previous_scaled_font != NULL)
  1580.         cairo_scaled_font_destroy (gstate->previous_scaled_font);
  1581.  
  1582.     gstate->previous_scaled_font = gstate->scaled_font;
  1583.     gstate->scaled_font = NULL;
  1584. }
  1585.  
  1586. cairo_status_t
  1587. _cairo_gstate_select_font_face (cairo_gstate_t       *gstate,
  1588.                                 const char           *family,
  1589.                                 cairo_font_slant_t    slant,
  1590.                                 cairo_font_weight_t   weight)
  1591. {
  1592.     cairo_font_face_t *font_face;
  1593.     cairo_status_t status;
  1594.  
  1595.     font_face = cairo_toy_font_face_create (family, slant, weight);
  1596.     if (font_face->status)
  1597.         return font_face->status;
  1598.  
  1599.     status = _cairo_gstate_set_font_face (gstate, font_face);
  1600.     cairo_font_face_destroy (font_face);
  1601.  
  1602.     return status;
  1603. }
  1604.  
  1605. cairo_status_t
  1606. _cairo_gstate_set_font_size (cairo_gstate_t *gstate,
  1607.                              double          size)
  1608. {
  1609.     _cairo_gstate_unset_scaled_font (gstate);
  1610.  
  1611.     cairo_matrix_init_scale (&gstate->font_matrix, size, size);
  1612.  
  1613.     return CAIRO_STATUS_SUCCESS;
  1614. }
  1615.  
  1616. cairo_status_t
  1617. _cairo_gstate_set_font_matrix (cairo_gstate_t       *gstate,
  1618.                                const cairo_matrix_t *matrix)
  1619. {
  1620.     if (memcmp (matrix, &gstate->font_matrix, sizeof (cairo_matrix_t)) == 0)
  1621.         return CAIRO_STATUS_SUCCESS;
  1622.  
  1623.     if (! _cairo_matrix_is_invertible (matrix))
  1624.         return _cairo_error (CAIRO_STATUS_INVALID_MATRIX);
  1625.  
  1626.     _cairo_gstate_unset_scaled_font (gstate);
  1627.  
  1628.     gstate->font_matrix = *matrix;
  1629.  
  1630.     return CAIRO_STATUS_SUCCESS;
  1631. }
  1632.  
  1633. void
  1634. _cairo_gstate_get_font_matrix (cairo_gstate_t *gstate,
  1635.                                cairo_matrix_t *matrix)
  1636. {
  1637.     *matrix = gstate->font_matrix;
  1638. }
  1639.  
  1640. void
  1641. _cairo_gstate_set_font_options (cairo_gstate_t             *gstate,
  1642.                                 const cairo_font_options_t *options)
  1643. {
  1644.     if (memcmp (options, &gstate->font_options, sizeof (cairo_font_options_t)) == 0)
  1645.         return;
  1646.  
  1647.     _cairo_gstate_unset_scaled_font (gstate);
  1648.  
  1649.     _cairo_font_options_init_copy (&gstate->font_options, options);
  1650. }
  1651.  
  1652. void
  1653. _cairo_gstate_get_font_options (cairo_gstate_t       *gstate,
  1654.                                 cairo_font_options_t *options)
  1655. {
  1656.     *options = gstate->font_options;
  1657. }
  1658.  
  1659. cairo_status_t
  1660. _cairo_gstate_get_font_face (cairo_gstate_t     *gstate,
  1661.                              cairo_font_face_t **font_face)
  1662. {
  1663.     cairo_status_t status;
  1664.  
  1665.     status = _cairo_gstate_ensure_font_face (gstate);
  1666.     if (unlikely (status))
  1667.         return status;
  1668.  
  1669.     *font_face = gstate->font_face;
  1670.  
  1671.     return CAIRO_STATUS_SUCCESS;
  1672. }
  1673.  
  1674. cairo_status_t
  1675. _cairo_gstate_get_scaled_font (cairo_gstate_t       *gstate,
  1676.                                cairo_scaled_font_t **scaled_font)
  1677. {
  1678.     cairo_status_t status;
  1679.  
  1680.     status = _cairo_gstate_ensure_scaled_font (gstate);
  1681.     if (unlikely (status))
  1682.         return status;
  1683.  
  1684.     *scaled_font = gstate->scaled_font;
  1685.  
  1686.     return CAIRO_STATUS_SUCCESS;
  1687. }
  1688.  
  1689. /*
  1690.  * Like everything else in this file, fonts involve Too Many Coordinate Spaces;
  1691.  * it is easy to get confused about what's going on.
  1692.  *
  1693.  * The user's view
  1694.  * ---------------
  1695.  *
  1696.  * Users ask for things in user space. When cairo starts, a user space unit
  1697.  * is about 1/96 inch, which is similar to (but importantly different from)
  1698.  * the normal "point" units most users think in terms of. When a user
  1699.  * selects a font, its scale is set to "one user unit". The user can then
  1700.  * independently scale the user coordinate system *or* the font matrix, in
  1701.  * order to adjust the rendered size of the font.
  1702.  *
  1703.  * Metrics are returned in user space, whether they are obtained from
  1704.  * the currently selected font in a  #cairo_t or from a #cairo_scaled_font_t
  1705.  * which is a font specialized to a particular scale matrix, CTM, and target
  1706.  * surface.
  1707.  *
  1708.  * The font's view
  1709.  * ---------------
  1710.  *
  1711.  * Fonts are designed and stored (in say .ttf files) in "font space", which
  1712.  * describes an "EM Square" (a design tile) and has some abstract number
  1713.  * such as 1000, 1024, or 2048 units per "EM". This is basically an
  1714.  * uninteresting space for us, but we need to remember that it exists.
  1715.  *
  1716.  * Font resources (from libraries or operating systems) render themselves
  1717.  * to a particular device. Since they do not want to make most programmers
  1718.  * worry about the font design space, the scaling API is simplified to
  1719.  * involve just telling the font the required pixel size of the EM square
  1720.  * (that is, in device space).
  1721.  *
  1722.  *
  1723.  * Cairo's gstate view
  1724.  * -------------------
  1725.  *
  1726.  * In addition to the CTM and CTM inverse, we keep a matrix in the gstate
  1727.  * called the "font matrix" which describes the user's most recent
  1728.  * font-scaling or font-transforming request. This is kept in terms of an
  1729.  * abstract scale factor, composed with the CTM and used to set the font's
  1730.  * pixel size. So if the user asks to "scale the font by 12", the matrix
  1731.  * is:
  1732.  *
  1733.  *   [ 12.0, 0.0, 0.0, 12.0, 0.0, 0.0 ]
  1734.  *
  1735.  * It is an affine matrix, like all cairo matrices, where its tx and ty
  1736.  * components are used to "nudging" fonts around and are handled in gstate
  1737.  * and then ignored by the "scaled-font" layer.
  1738.  *
  1739.  * In order to perform any action on a font, we must build an object
  1740.  * called a #cairo_font_scale_t; this contains the central 2x2 matrix
  1741.  * resulting from "font matrix * CTM" (sans the font matrix translation
  1742.  * components as stated in the previous paragraph).
  1743.  *
  1744.  * We pass this to the font when making requests of it, which causes it to
  1745.  * reply for a particular [user request, device] combination, under the CTM
  1746.  * (to accommodate the "zoom in" == "bigger fonts" issue above).
  1747.  *
  1748.  * The other terms in our communication with the font are therefore in
  1749.  * device space. When we ask it to perform text->glyph conversion, it will
  1750.  * produce a glyph string in device space. Glyph vectors we pass to it for
  1751.  * measuring or rendering should be in device space. The metrics which we
  1752.  * get back from the font will be in device space. The contents of the
  1753.  * global glyph image cache will be in device space.
  1754.  *
  1755.  *
  1756.  * Cairo's public view
  1757.  * -------------------
  1758.  *
  1759.  * Since the values entering and leaving via public API calls are in user
  1760.  * space, the gstate functions typically need to multiply arguments by the
  1761.  * CTM (for user-input glyph vectors), and return values by the CTM inverse
  1762.  * (for font responses such as metrics or glyph vectors).
  1763.  *
  1764.  */
  1765.  
  1766. static cairo_status_t
  1767. _cairo_gstate_ensure_font_face (cairo_gstate_t *gstate)
  1768. {
  1769.     cairo_font_face_t *font_face;
  1770.  
  1771.     if (gstate->font_face != NULL)
  1772.         return gstate->font_face->status;
  1773.  
  1774.  
  1775.     font_face = cairo_toy_font_face_create (CAIRO_FONT_FAMILY_DEFAULT,
  1776.                                             CAIRO_FONT_SLANT_DEFAULT,
  1777.                                             CAIRO_FONT_WEIGHT_DEFAULT);
  1778.     if (font_face->status)
  1779.         return font_face->status;
  1780.  
  1781.     gstate->font_face = font_face;
  1782.  
  1783.     return CAIRO_STATUS_SUCCESS;
  1784. }
  1785.  
  1786. static cairo_status_t
  1787. _cairo_gstate_ensure_scaled_font (cairo_gstate_t *gstate)
  1788. {
  1789.     cairo_status_t status;
  1790.     cairo_font_options_t options;
  1791.     cairo_scaled_font_t *scaled_font;
  1792.  
  1793.     if (gstate->scaled_font != NULL)
  1794.         return gstate->scaled_font->status;
  1795.  
  1796.     status = _cairo_gstate_ensure_font_face (gstate);
  1797.     if (unlikely (status))
  1798.         return status;
  1799.  
  1800.     cairo_surface_get_font_options (gstate->target, &options);
  1801.     cairo_font_options_merge (&options, &gstate->font_options);
  1802.  
  1803.     scaled_font = cairo_scaled_font_create (gstate->font_face,
  1804.                                             &gstate->font_matrix,
  1805.                                             &gstate->ctm,
  1806.                                             &options);
  1807.  
  1808.     status = cairo_scaled_font_status (scaled_font);
  1809.     if (unlikely (status))
  1810.         return status;
  1811.  
  1812.     gstate->scaled_font = scaled_font;
  1813.  
  1814.     return CAIRO_STATUS_SUCCESS;
  1815. }
  1816.  
  1817. cairo_status_t
  1818. _cairo_gstate_get_font_extents (cairo_gstate_t *gstate,
  1819.                                 cairo_font_extents_t *extents)
  1820. {
  1821.     cairo_status_t status = _cairo_gstate_ensure_scaled_font (gstate);
  1822.     if (unlikely (status))
  1823.         return status;
  1824.  
  1825.     cairo_scaled_font_extents (gstate->scaled_font, extents);
  1826.  
  1827.     return cairo_scaled_font_status (gstate->scaled_font);
  1828. }
  1829.  
  1830. cairo_status_t
  1831. _cairo_gstate_text_to_glyphs (cairo_gstate_t             *gstate,
  1832.                               double                      x,
  1833.                               double                      y,
  1834.                               const char                 *utf8,
  1835.                               int                         utf8_len,
  1836.                               cairo_glyph_t             **glyphs,
  1837.                               int                        *num_glyphs,
  1838.                               cairo_text_cluster_t      **clusters,
  1839.                               int                        *num_clusters,
  1840.                               cairo_text_cluster_flags_t *cluster_flags)
  1841. {
  1842.     cairo_status_t status;
  1843.  
  1844.     status = _cairo_gstate_ensure_scaled_font (gstate);
  1845.     if (unlikely (status))
  1846.         return status;
  1847.  
  1848.     return cairo_scaled_font_text_to_glyphs (gstate->scaled_font, x, y,
  1849.                                              utf8, utf8_len,
  1850.                                              glyphs, num_glyphs,
  1851.                                              clusters, num_clusters,
  1852.                                              cluster_flags);
  1853. }
  1854.  
  1855. cairo_status_t
  1856. _cairo_gstate_set_font_face (cairo_gstate_t    *gstate,
  1857.                              cairo_font_face_t *font_face)
  1858. {
  1859.     if (font_face && font_face->status)
  1860.         return _cairo_error (font_face->status);
  1861.  
  1862.     if (font_face == gstate->font_face)
  1863.         return CAIRO_STATUS_SUCCESS;
  1864.  
  1865.     cairo_font_face_destroy (gstate->font_face);
  1866.     gstate->font_face = cairo_font_face_reference (font_face);
  1867.  
  1868.     _cairo_gstate_unset_scaled_font (gstate);
  1869.  
  1870.     return CAIRO_STATUS_SUCCESS;
  1871. }
  1872.  
  1873. cairo_status_t
  1874. _cairo_gstate_glyph_extents (cairo_gstate_t *gstate,
  1875.                              const cairo_glyph_t *glyphs,
  1876.                              int num_glyphs,
  1877.                              cairo_text_extents_t *extents)
  1878. {
  1879.     cairo_status_t status;
  1880.  
  1881.     status = _cairo_gstate_ensure_scaled_font (gstate);
  1882.     if (unlikely (status))
  1883.         return status;
  1884.  
  1885.     cairo_scaled_font_glyph_extents (gstate->scaled_font,
  1886.                                      glyphs, num_glyphs,
  1887.                                      extents);
  1888.  
  1889.     return cairo_scaled_font_status (gstate->scaled_font);
  1890. }
  1891.  
  1892. cairo_status_t
  1893. _cairo_gstate_show_text_glyphs (cairo_gstate_t             *gstate,
  1894.                                 const char                 *utf8,
  1895.                                 int                         utf8_len,
  1896.                                 const cairo_glyph_t        *glyphs,
  1897.                                 int                         num_glyphs,
  1898.                                 const cairo_text_cluster_t *clusters,
  1899.                                 int                         num_clusters,
  1900.                                 cairo_text_cluster_flags_t  cluster_flags)
  1901. {
  1902.     cairo_pattern_union_t source_pattern;
  1903.     const cairo_pattern_t *pattern;
  1904.     cairo_glyph_t stack_transformed_glyphs[CAIRO_STACK_ARRAY_LENGTH (cairo_glyph_t)];
  1905.     cairo_glyph_t *transformed_glyphs;
  1906.     cairo_text_cluster_t stack_transformed_clusters[CAIRO_STACK_ARRAY_LENGTH (cairo_text_cluster_t)];
  1907.     cairo_text_cluster_t *transformed_clusters;
  1908.     cairo_operator_t op;
  1909.     cairo_status_t status;
  1910.     cairo_clip_t clip;
  1911.  
  1912.     if (unlikely (gstate->source->status))
  1913.         return gstate->source->status;
  1914.  
  1915.     if (gstate->op == CAIRO_OPERATOR_DEST)
  1916.         return CAIRO_STATUS_SUCCESS;
  1917.  
  1918.     if (_clipped (gstate))
  1919.         return CAIRO_STATUS_SUCCESS;
  1920.  
  1921.     status = _cairo_gstate_ensure_scaled_font (gstate);
  1922.     if (unlikely (status))
  1923.         return status;
  1924.  
  1925.     transformed_glyphs = stack_transformed_glyphs;
  1926.     transformed_clusters = stack_transformed_clusters;
  1927.  
  1928.     if (num_glyphs > ARRAY_LENGTH (stack_transformed_glyphs)) {
  1929.         transformed_glyphs = cairo_glyph_allocate (num_glyphs);
  1930.         if (unlikely (transformed_glyphs == NULL)) {
  1931.             status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
  1932.             goto CLEANUP_GLYPHS;
  1933.         }
  1934.     }
  1935.  
  1936.     /* Just in case */
  1937.     if (!clusters)
  1938.         num_clusters = 0;
  1939.  
  1940.     if (num_clusters > ARRAY_LENGTH (stack_transformed_clusters)) {
  1941.         transformed_clusters = cairo_text_cluster_allocate (num_clusters);
  1942.         if (unlikely (transformed_clusters == NULL)) {
  1943.             status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
  1944.             goto CLEANUP_GLYPHS;
  1945.         }
  1946.     }
  1947.  
  1948.     status = _cairo_gstate_transform_glyphs_to_backend (gstate,
  1949.                                                         glyphs, num_glyphs,
  1950.                                                         clusters,
  1951.                                                         num_clusters,
  1952.                                                         cluster_flags,
  1953.                                                         transformed_glyphs,
  1954.                                                         &num_glyphs,
  1955.                                                         transformed_clusters);
  1956.  
  1957.     if (status || num_glyphs == 0)
  1958.         goto CLEANUP_GLYPHS;
  1959.  
  1960.     op = _reduce_op (gstate);
  1961.     if (op == CAIRO_OPERATOR_CLEAR) {
  1962.         pattern = &_cairo_pattern_clear.base;
  1963.     } else {
  1964.         _cairo_gstate_copy_transformed_source (gstate, &source_pattern.base);
  1965.         pattern = &source_pattern.base;
  1966.     }
  1967.  
  1968.     /* For really huge font sizes, we can just do path;fill instead of
  1969.      * show_glyphs, as show_glyphs would put excess pressure on the cache,
  1970.      * and moreover, not all components below us correctly handle huge font
  1971.      * sizes.  I wanted to set the limit at 256.  But alas, seems like cairo's
  1972.      * rasterizer is something like ten times slower than freetype's for huge
  1973.      * sizes.  So, no win just yet.  For now, do it for insanely-huge sizes,
  1974.      * just to make sure we don't make anyone unhappy.  When we get a really
  1975.      * fast rasterizer in cairo, we may want to readjust this.
  1976.      *
  1977.      * Needless to say, do this only if show_text_glyphs is not available. */
  1978.     if (cairo_surface_has_show_text_glyphs (gstate->target) ||
  1979.         _cairo_scaled_font_get_max_scale (gstate->scaled_font) <= 10240)
  1980.     {
  1981.         status = _cairo_surface_show_text_glyphs (gstate->target, op, pattern,
  1982.                                                   utf8, utf8_len,
  1983.                                                   transformed_glyphs, num_glyphs,
  1984.                                                   transformed_clusters, num_clusters,
  1985.                                                   cluster_flags,
  1986.                                                   gstate->scaled_font,
  1987.                                                   _gstate_get_clip (gstate, &clip));
  1988.     }
  1989.     else
  1990.     {
  1991.         cairo_path_fixed_t path;
  1992.  
  1993.         _cairo_path_fixed_init (&path);
  1994.  
  1995.         status = _cairo_scaled_font_glyph_path (gstate->scaled_font,
  1996.                                                 transformed_glyphs, num_glyphs,
  1997.                                                 &path);
  1998.  
  1999.         if (status == CAIRO_STATUS_SUCCESS) {
  2000.             status = _cairo_surface_fill (gstate->target, op, pattern,
  2001.                                           &path,
  2002.                                           CAIRO_FILL_RULE_WINDING,
  2003.                                           gstate->tolerance,
  2004.                                           gstate->scaled_font->options.antialias,
  2005.                                           _gstate_get_clip (gstate, &clip));
  2006.         }
  2007.  
  2008.         _cairo_path_fixed_fini (&path);
  2009.     }
  2010.  
  2011.     _cairo_clip_fini (&clip);
  2012.  
  2013. CLEANUP_GLYPHS:
  2014.     if (transformed_glyphs != stack_transformed_glyphs)
  2015.       cairo_glyph_free (transformed_glyphs);
  2016.     if (transformed_clusters != stack_transformed_clusters)
  2017.       cairo_text_cluster_free (transformed_clusters);
  2018.  
  2019.     return status;
  2020. }
  2021.  
  2022. cairo_status_t
  2023. _cairo_gstate_glyph_path (cairo_gstate_t      *gstate,
  2024.                           const cairo_glyph_t *glyphs,
  2025.                           int                  num_glyphs,
  2026.                           cairo_path_fixed_t  *path)
  2027. {
  2028.     cairo_status_t status;
  2029.     cairo_glyph_t *transformed_glyphs;
  2030.     cairo_glyph_t stack_transformed_glyphs[CAIRO_STACK_ARRAY_LENGTH (cairo_glyph_t)];
  2031.  
  2032.     status = _cairo_gstate_ensure_scaled_font (gstate);
  2033.     if (unlikely (status))
  2034.         return status;
  2035.  
  2036.     if (num_glyphs < ARRAY_LENGTH (stack_transformed_glyphs)) {
  2037.       transformed_glyphs = stack_transformed_glyphs;
  2038.     } else {
  2039.         transformed_glyphs = cairo_glyph_allocate (num_glyphs);
  2040.         if (unlikely (transformed_glyphs == NULL))
  2041.             return _cairo_error (CAIRO_STATUS_NO_MEMORY);
  2042.     }
  2043.  
  2044.     status = _cairo_gstate_transform_glyphs_to_backend (gstate,
  2045.                                                         glyphs, num_glyphs,
  2046.                                                         NULL, 0, 0,
  2047.                                                         transformed_glyphs,
  2048.                                                         NULL, NULL);
  2049.     if (unlikely (status))
  2050.         goto CLEANUP_GLYPHS;
  2051.  
  2052.     status = _cairo_scaled_font_glyph_path (gstate->scaled_font,
  2053.                                             transformed_glyphs, num_glyphs,
  2054.                                             path);
  2055.  
  2056.   CLEANUP_GLYPHS:
  2057.     if (transformed_glyphs != stack_transformed_glyphs)
  2058.       cairo_glyph_free (transformed_glyphs);
  2059.  
  2060.     return status;
  2061. }
  2062.  
  2063. cairo_status_t
  2064. _cairo_gstate_set_antialias (cairo_gstate_t *gstate,
  2065.                              cairo_antialias_t antialias)
  2066. {
  2067.     gstate->antialias = antialias;
  2068.  
  2069.     return CAIRO_STATUS_SUCCESS;
  2070. }
  2071.  
  2072. cairo_antialias_t
  2073. _cairo_gstate_get_antialias (cairo_gstate_t *gstate)
  2074. {
  2075.     return gstate->antialias;
  2076. }
  2077.  
  2078. /**
  2079.  * _cairo_gstate_transform_glyphs_to_backend:
  2080.  * @gstate: a #cairo_gstate_t
  2081.  * @glyphs: the array of #cairo_glyph_t objects to be transformed
  2082.  * @num_glyphs: the number of elements in @glyphs
  2083.  * @transformed_glyphs: a pre-allocated array of at least @num_glyphs
  2084.  * #cairo_glyph_t objects
  2085.  * @num_transformed_glyphs: the number of elements in @transformed_glyphs
  2086.  * after dropping out of bounds glyphs, or %NULL if glyphs shouldn't be
  2087.  * dropped
  2088.  *
  2089.  * Transform an array of glyphs to backend space by first adding the offset
  2090.  * of the font matrix, then transforming from user space to backend space.
  2091.  * The result of the transformation is placed in @transformed_glyphs.
  2092.  *
  2093.  * This also uses information from the scaled font and the surface to
  2094.  * cull/drop glyphs that will not be visible.
  2095.  **/
  2096. static cairo_status_t
  2097. _cairo_gstate_transform_glyphs_to_backend (cairo_gstate_t       *gstate,
  2098.                                            const cairo_glyph_t  *glyphs,
  2099.                                            int                   num_glyphs,
  2100.                                            const cairo_text_cluster_t   *clusters,
  2101.                                            int                   num_clusters,
  2102.                                            cairo_text_cluster_flags_t cluster_flags,
  2103.                                            cairo_glyph_t        *transformed_glyphs,
  2104.                                            int                  *num_transformed_glyphs,
  2105.                                            cairo_text_cluster_t *transformed_clusters)
  2106. {
  2107.     int i, j, k;
  2108.     cairo_matrix_t *ctm = &gstate->ctm;
  2109.     cairo_matrix_t *font_matrix = &gstate->font_matrix;
  2110.     cairo_matrix_t *device_transform = &gstate->target->device_transform;
  2111.     cairo_bool_t drop = FALSE;
  2112.     double x1 = 0, x2 = 0, y1 = 0, y2 = 0;
  2113.  
  2114.     if (num_transformed_glyphs != NULL) {
  2115.         cairo_rectangle_int_t surface_extents;
  2116.  
  2117.         drop = TRUE;
  2118.         if (! _cairo_gstate_int_clip_extents (gstate, &surface_extents)) {
  2119.             drop = FALSE; /* unbounded surface */
  2120.         } else {
  2121.             double scale10 = 10 * _cairo_scaled_font_get_max_scale (gstate->scaled_font);
  2122.             if (surface_extents.width == 0 || surface_extents.height == 0) {
  2123.               /* No visible area.  Don't draw anything */
  2124.               *num_transformed_glyphs = 0;
  2125.               return CAIRO_STATUS_SUCCESS;
  2126.             }
  2127.             /* XXX We currently drop any glyphs that has its position outside
  2128.              * of the surface boundaries by a safety margin depending on the
  2129.              * font scale.  This however can fail in extreme cases where the
  2130.              * font has really long swashes for example...  We can correctly
  2131.              * handle that by looking the glyph up and using its device bbox
  2132.              * to device if it's going to be visible, but I'm not inclined to
  2133.              * do that now.
  2134.              */
  2135.             x1 = surface_extents.x - scale10;
  2136.             y1 = surface_extents.y - scale10;
  2137.             x2 = surface_extents.x + (int) surface_extents.width  + scale10;
  2138.             y2 = surface_extents.y + (int) surface_extents.height + scale10;
  2139.         }
  2140.  
  2141.         if (!drop)
  2142.             *num_transformed_glyphs = num_glyphs;
  2143.     } else
  2144.         num_transformed_glyphs = &j;
  2145.  
  2146. #define KEEP_GLYPH(glyph) (x1 <= glyph.x && glyph.x <= x2 && y1 <= glyph.y && glyph.y <= y2)
  2147.  
  2148.     j = 0;
  2149.     if (_cairo_matrix_is_identity (ctm) &&
  2150.         _cairo_matrix_is_identity (device_transform) &&
  2151.         font_matrix->x0 == 0 && font_matrix->y0 == 0)
  2152.     {
  2153.         if (! drop) {
  2154.             memcpy (transformed_glyphs, glyphs,
  2155.                     num_glyphs * sizeof (cairo_glyph_t));
  2156.             j = num_glyphs;
  2157.         } else if (num_clusters == 0) {
  2158.             for (i = 0; i < num_glyphs; i++) {
  2159.                 transformed_glyphs[j].index = glyphs[i].index;
  2160.                 transformed_glyphs[j].x = glyphs[i].x;
  2161.                 transformed_glyphs[j].y = glyphs[i].y;
  2162.                 if (KEEP_GLYPH (transformed_glyphs[j]))
  2163.                     j++;
  2164.             }
  2165.         } else {
  2166.             const cairo_glyph_t *cur_glyph;
  2167.  
  2168.             if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD)
  2169.                 cur_glyph = glyphs + num_glyphs - 1;
  2170.             else
  2171.                 cur_glyph = glyphs;
  2172.  
  2173.             for (i = 0; i < num_clusters; i++) {
  2174.                 cairo_bool_t cluster_visible = FALSE;
  2175.  
  2176.                 for (k = 0; k < clusters[i].num_glyphs; k++) {
  2177.                     transformed_glyphs[j+k].index = cur_glyph->index;
  2178.                     transformed_glyphs[j+k].x = cur_glyph->x;
  2179.                     transformed_glyphs[j+k].y = cur_glyph->y;
  2180.                     if (KEEP_GLYPH (transformed_glyphs[j+k]))
  2181.                         cluster_visible = TRUE;
  2182.  
  2183.                     if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD)
  2184.                         cur_glyph--;
  2185.                     else
  2186.                         cur_glyph++;
  2187.                 }
  2188.  
  2189.                 transformed_clusters[i] = clusters[i];
  2190.                 if (cluster_visible)
  2191.                     j += k;
  2192.                 else
  2193.                     transformed_clusters[i].num_glyphs = 0;
  2194.             }
  2195.         }
  2196.     }
  2197.     else if (_cairo_matrix_is_translation (ctm) &&
  2198.              _cairo_matrix_is_translation (device_transform))
  2199.     {
  2200.         double tx = font_matrix->x0 + ctm->x0 + device_transform->x0;
  2201.         double ty = font_matrix->y0 + ctm->y0 + device_transform->y0;
  2202.  
  2203.         if (! drop || num_clusters == 0) {
  2204.             for (i = 0; i < num_glyphs; i++) {
  2205.                 transformed_glyphs[j].index = glyphs[i].index;
  2206.                 transformed_glyphs[j].x = glyphs[i].x + tx;
  2207.                 transformed_glyphs[j].y = glyphs[i].y + ty;
  2208.                 if (!drop || KEEP_GLYPH (transformed_glyphs[j]))
  2209.                     j++;
  2210.             }
  2211.         } else {
  2212.             const cairo_glyph_t *cur_glyph;
  2213.  
  2214.             if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD)
  2215.                 cur_glyph = glyphs + num_glyphs - 1;
  2216.             else
  2217.                 cur_glyph = glyphs;
  2218.  
  2219.             for (i = 0; i < num_clusters; i++) {
  2220.                 cairo_bool_t cluster_visible = FALSE;
  2221.  
  2222.                 for (k = 0; k < clusters[i].num_glyphs; k++) {
  2223.                     transformed_glyphs[j+k].index = cur_glyph->index;
  2224.                     transformed_glyphs[j+k].x = cur_glyph->x + tx;
  2225.                     transformed_glyphs[j+k].y = cur_glyph->y + ty;
  2226.                     if (KEEP_GLYPH (transformed_glyphs[j+k]))
  2227.                         cluster_visible = TRUE;
  2228.  
  2229.                     if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD)
  2230.                         cur_glyph--;
  2231.                     else
  2232.                         cur_glyph++;
  2233.                 }
  2234.  
  2235.                 transformed_clusters[i] = clusters[i];
  2236.                 if (cluster_visible)
  2237.                     j += k;
  2238.                 else
  2239.                     transformed_clusters[i].num_glyphs = 0;
  2240.             }
  2241.         }
  2242.     }
  2243.     else
  2244.     {
  2245.         cairo_matrix_t aggregate_transform;
  2246.  
  2247.         cairo_matrix_init_translate (&aggregate_transform,
  2248.                                      gstate->font_matrix.x0,
  2249.                                      gstate->font_matrix.y0);
  2250.         cairo_matrix_multiply (&aggregate_transform,
  2251.                                &aggregate_transform, ctm);
  2252.         cairo_matrix_multiply (&aggregate_transform,
  2253.                                &aggregate_transform, device_transform);
  2254.  
  2255.         if (! drop || num_clusters == 0) {
  2256.             for (i = 0; i < num_glyphs; i++) {
  2257.                 transformed_glyphs[j] = glyphs[i];
  2258.                 cairo_matrix_transform_point (&aggregate_transform,
  2259.                                               &transformed_glyphs[j].x,
  2260.                                               &transformed_glyphs[j].y);
  2261.                 if (! drop || KEEP_GLYPH (transformed_glyphs[j]))
  2262.                     j++;
  2263.             }
  2264.         } else {
  2265.             const cairo_glyph_t *cur_glyph;
  2266.  
  2267.             if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD)
  2268.                 cur_glyph = glyphs + num_glyphs - 1;
  2269.             else
  2270.                 cur_glyph = glyphs;
  2271.  
  2272.             for (i = 0; i < num_clusters; i++) {
  2273.                 cairo_bool_t cluster_visible = FALSE;
  2274.                 for (k = 0; k < clusters[i].num_glyphs; k++) {
  2275.                     transformed_glyphs[j+k] = *cur_glyph;
  2276.                     cairo_matrix_transform_point (&aggregate_transform,
  2277.                                                   &transformed_glyphs[j+k].x,
  2278.                                                   &transformed_glyphs[j+k].y);
  2279.                     if (KEEP_GLYPH (transformed_glyphs[j+k]))
  2280.                         cluster_visible = TRUE;
  2281.  
  2282.                     if (cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD)
  2283.                         cur_glyph--;
  2284.                     else
  2285.                         cur_glyph++;
  2286.                 }
  2287.  
  2288.                 transformed_clusters[i] = clusters[i];
  2289.                 if (cluster_visible)
  2290.                     j += k;
  2291.                 else
  2292.                     transformed_clusters[i].num_glyphs = 0;
  2293.             }
  2294.         }
  2295.     }
  2296.     *num_transformed_glyphs = j;
  2297.  
  2298.     if (num_clusters != 0 && cluster_flags & CAIRO_TEXT_CLUSTER_FLAG_BACKWARD) {
  2299.         for (i = 0; i < --j; i++) {
  2300.             cairo_glyph_t tmp;
  2301.  
  2302.             tmp = transformed_glyphs[i];
  2303.             transformed_glyphs[i] = transformed_glyphs[j];
  2304.             transformed_glyphs[j] = tmp;
  2305.         }
  2306.     }
  2307.  
  2308.     return CAIRO_STATUS_SUCCESS;
  2309. }
  2310.