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/*

 * Mesa 3-D graphics library

 *

 * Copyright (C) 1999  Brian Paul   All Rights Reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * the rights to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included

 * in all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR

 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,

 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

 * OTHER DEALINGS IN THE SOFTWARE.

 */

/* xfonts.c -- glXUseXFont() for Mesa written by

 * Copyright (C) 1995 Thorsten.Ohl @ Physik.TH-Darmstadt.de

 */

/*

  This was take from Mesa and modified to work in the real GLX structure.

  It provides a fully client side implementation of glXUseXFont and is

  called by that routine when direct rendering is enabled.

*/

#ifdef GLX_DIRECT_RENDERING

#include "glxclient.h"

/* Some debugging info.  */

#ifdef DEBUG

#undef _R

#undef _G

#undef _B

#include 

int debug_xfonts = 0;

static void

dump_char_struct(XCharStruct * ch, char *prefix)

{

   printf("%slbearing = %d, rbearing = %d, width = %d\n",

          prefix, ch->lbearing, ch->rbearing, ch->width);

   printf("%sascent = %d, descent = %d, attributes = %u\n",

          prefix, ch->ascent, ch->descent, (unsigned int) ch->attributes);

}

static void

dump_font_struct(XFontStruct * font)

{

   printf("ascent = %d, descent = %d\n", font->ascent, font->descent);

   printf("char_or_byte2 = (%u,%u)\n",

          font->min_char_or_byte2, font->max_char_or_byte2);

   printf("byte1 = (%u,%u)\n", font->min_byte1, font->max_byte1);

   printf("all_chars_exist = %s\n", font->all_chars_exist ? "True" : "False");

   printf("default_char = %c (\\%03o)\n",

          (char) (isprint(font->default_char) ? font->default_char : ' '),

          font->default_char);

   dump_char_struct(&font->min_bounds, "min> ");

   dump_char_struct(&font->max_bounds, "max> ");

#if 0

   for (c = font->min_char_or_byte2; c <= font->max_char_or_byte2; c++) {

      char prefix[8];

      sprintf(prefix, "%d> ", c);

      dump_char_struct(&font->per_char[c], prefix);

   }

#endif

}

static void

dump_bitmap(unsigned int width, unsigned int height, GLubyte * bitmap)

{

   unsigned int x, y;

   printf("    ");

   for (x = 0; x < 8 * width; x++)

      printf("%o", 7 - (x % 8));

   putchar('\n');

   for (y = 0; y < height; y++) {

      printf("%3o:", y);

      for (x = 0; x < 8 * width; x++)

         putchar((bitmap[width * (height - y - 1) + x / 8] & (1 << (7 - (x %

                                                                         8))))

                 ? '*' : '.');

      printf("   ");

      for (x = 0; x < width; x++)

         printf("0x%02x, ", bitmap[width * (height - y - 1) + x]);

      putchar('\n');

   }

}

#endif /* DEBUG */

/* Implementation.  */

/* Fill a BITMAP with a character C from thew current font

   in the graphics context GC.  WIDTH is the width in bytes

   and HEIGHT is the height in bits.

   Note that the generated bitmaps must be used with

        glPixelStorei (GL_UNPACK_SWAP_BYTES, GL_FALSE);

        glPixelStorei (GL_UNPACK_LSB_FIRST, GL_FALSE);

        glPixelStorei (GL_UNPACK_ROW_LENGTH, 0);

        glPixelStorei (GL_UNPACK_SKIP_ROWS, 0);

        glPixelStorei (GL_UNPACK_SKIP_PIXELS, 0);

        glPixelStorei (GL_UNPACK_ALIGNMENT, 1);

   Possible optimizations:

     * use only one reusable pixmap with the maximum dimensions.

     * draw the entire font into a single pixmap (careful with

       proportional fonts!).

*/

/*

 * Generate OpenGL-compatible bitmap.

 */

static void

fill_bitmap(Display * dpy, Window win, GC gc,

            unsigned int width, unsigned int height,

            int x0, int y0, unsigned int c, GLubyte * bitmap)

{

   XImage *image;

   unsigned int x, y;

   Pixmap pixmap;

   XChar2b char2b;

   pixmap = XCreatePixmap(dpy, win, 8 * width, height, 1);

   XSetForeground(dpy, gc, 0);

   XFillRectangle(dpy, pixmap, gc, 0, 0, 8 * width, height);

   XSetForeground(dpy, gc, 1);

   char2b.byte1 = (c >> 8) & 0xff;

   char2b.byte2 = (c & 0xff);

   XDrawString16(dpy, pixmap, gc, x0, y0, &char2b, 1);

   image = XGetImage(dpy, pixmap, 0, 0, 8 * width, height, 1, XYPixmap);

   if (image) {

      /* Fill the bitmap (X11 and OpenGL are upside down wrt each other).  */

      for (y = 0; y < height; y++)

         for (x = 0; x < 8 * width; x++)

            if (XGetPixel(image, x, y))

               bitmap[width * (height - y - 1) + x / 8] |=

                  (1 << (7 - (x % 8)));

      XDestroyImage(image);

   }

   XFreePixmap(dpy, pixmap);

}

/*

 * determine if a given glyph is valid and return the

 * corresponding XCharStruct.

 */

static XCharStruct *

isvalid(XFontStruct * fs, int which)

{

   unsigned int rows, pages;

   int byte1 = 0, byte2 = 0;

   int i, valid = 1;

   rows = fs->max_byte1 - fs->min_byte1 + 1;

   pages = fs->max_char_or_byte2 - fs->min_char_or_byte2 + 1;

   if (rows == 1) {

      /* "linear" fonts */

      if ((fs->min_char_or_byte2 > which) || (fs->max_char_or_byte2 < which))

         valid = 0;

   }

   else {

      /* "matrix" fonts */

      byte2 = which & 0xff;

      byte1 = which >> 8;

      if ((fs->min_char_or_byte2 > byte2) ||

          (fs->max_char_or_byte2 < byte2) ||

          (fs->min_byte1 > byte1) || (fs->max_byte1 < byte1))

         valid = 0;

   }

   if (valid) {

      if (fs->per_char) {

         if (rows == 1) {

            /* "linear" fonts */

            return (fs->per_char + (which - fs->min_char_or_byte2));

         }

         else {

            /* "matrix" fonts */

            i = ((byte1 - fs->min_byte1) * pages) +

               (byte2 - fs->min_char_or_byte2);

            return (fs->per_char + i);

         }

      }

      else {

         return (&fs->min_bounds);

      }

   }

   return (NULL);

}

_X_HIDDEN void

DRI_glXUseXFont(struct glx_context *CC, Font font, int first, int count, int listbase)

{

   Display *dpy;

   Window win;

   Pixmap pixmap;

   GC gc;

   XGCValues values;

   unsigned long valuemask;

   XFontStruct *fs;

   GLint swapbytes, lsbfirst, rowlength;

   GLint skiprows, skippixels, alignment;

   unsigned int max_width, max_height, max_bm_width, max_bm_height;

   GLubyte *bm;

   int i;

   dpy = CC->currentDpy;

   win = CC->currentDrawable;

   fs = XQueryFont(dpy, font);

   if (!fs) {

      __glXSetError(CC, GL_INVALID_VALUE);

      return;

   }

   /* Allocate a bitmap that can fit all characters.  */

   max_width = fs->max_bounds.rbearing - fs->min_bounds.lbearing;

   max_height = fs->max_bounds.ascent + fs->max_bounds.descent;

   max_bm_width = (max_width + 7) / 8;

   max_bm_height = max_height;

   bm = malloc((max_bm_width * max_bm_height) * sizeof(GLubyte));

   if (!bm) {

      XFreeFontInfo(NULL, fs, 1);

      __glXSetError(CC, GL_OUT_OF_MEMORY);

      return;

   }

#if 0

   /* get the page info */

   pages = fs->max_char_or_byte2 - fs->min_char_or_byte2 + 1;

   firstchar = (fs->min_byte1 << 8) + fs->min_char_or_byte2;

   lastchar = (fs->max_byte1 << 8) + fs->max_char_or_byte2;

   rows = fs->max_byte1 - fs->min_byte1 + 1;

   unsigned int first_char, last_char, pages, rows;

#endif

   /* Save the current packing mode for bitmaps.  */

   glGetIntegerv(GL_UNPACK_SWAP_BYTES, &swapbytes);

   glGetIntegerv(GL_UNPACK_LSB_FIRST, &lsbfirst);

   glGetIntegerv(GL_UNPACK_ROW_LENGTH, &rowlength);

   glGetIntegerv(GL_UNPACK_SKIP_ROWS, &skiprows);

   glGetIntegerv(GL_UNPACK_SKIP_PIXELS, &skippixels);

   glGetIntegerv(GL_UNPACK_ALIGNMENT, &alignment);

   /* Enforce a standard packing mode which is compatible with

      fill_bitmap() from above.  This is actually the default mode,

      except for the (non)alignment.  */

   glPixelStorei(GL_UNPACK_SWAP_BYTES, GL_FALSE);

   glPixelStorei(GL_UNPACK_LSB_FIRST, GL_FALSE);

   glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);

   glPixelStorei(GL_UNPACK_SKIP_ROWS, 0);

   glPixelStorei(GL_UNPACK_SKIP_PIXELS, 0);

   glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

   pixmap = XCreatePixmap(dpy, win, 10, 10, 1);

   values.foreground = BlackPixel(dpy, DefaultScreen(dpy));

   values.background = WhitePixel(dpy, DefaultScreen(dpy));

   values.font = fs->fid;

   valuemask = GCForeground | GCBackground | GCFont;

   gc = XCreateGC(dpy, pixmap, valuemask, &values);

   XFreePixmap(dpy, pixmap);

#ifdef DEBUG

   if (debug_xfonts)

      dump_font_struct(fs);

#endif

   for (i = 0; i < count; i++) {

      unsigned int width, height, bm_width, bm_height;

      GLfloat x0, y0, dx, dy;

      XCharStruct *ch;

      int x, y;

      unsigned int c = first + i;

      int list = listbase + i;

      int valid;

      /* check on index validity and get the bounds */

      ch = isvalid(fs, c);

      if (!ch) {

         ch = &fs->max_bounds;

         valid = 0;

      }

      else {

         valid = 1;

      }

#ifdef DEBUG

      if (debug_xfonts) {

         char s[7];

         sprintf(s, isprint(c) ? "%c> " : "\\%03o> ", c);

         dump_char_struct(ch, s);

      }

#endif

      /* glBitmap()' parameters:

         straight from the glXUseXFont(3) manpage.  */

      width = ch->rbearing - ch->lbearing;

      height = ch->ascent + ch->descent;

      x0 = -ch->lbearing;

      y0 = ch->descent - 1;

      dx = ch->width;

      dy = 0;

      /* X11's starting point.  */

      x = -ch->lbearing;

      y = ch->ascent;

      /* Round the width to a multiple of eight.  We will use this also

         for the pixmap for capturing the X11 font.  This is slightly

         inefficient, but it makes the OpenGL part real easy.  */

      bm_width = (width + 7) / 8;

      bm_height = height;

      glNewList(list, GL_COMPILE);

      if (valid && (bm_width > 0) && (bm_height > 0)) {

         memset(bm, '\0', bm_width * bm_height);

         fill_bitmap(dpy, win, gc, bm_width, bm_height, x, y, c, bm);

         glBitmap(width, height, x0, y0, dx, dy, bm);

#ifdef DEBUG

         if (debug_xfonts) {

            printf("width/height = %u/%u\n", width, height);

            printf("bm_width/bm_height = %u/%u\n", bm_width, bm_height);

            dump_bitmap(bm_width, bm_height, bm);

         }

#endif

      }

      else {

         glBitmap(0, 0, 0.0, 0.0, dx, dy, NULL);

      }

      glEndList();

   }

   free(bm);

   XFreeFontInfo(NULL, fs, 1);

   XFreeGC(dpy, gc);

   /* Restore saved packing modes.  */

   glPixelStorei(GL_UNPACK_SWAP_BYTES, swapbytes);

   glPixelStorei(GL_UNPACK_LSB_FIRST, lsbfirst);

   glPixelStorei(GL_UNPACK_ROW_LENGTH, rowlength);

   glPixelStorei(GL_UNPACK_SKIP_ROWS, skiprows);

   glPixelStorei(GL_UNPACK_SKIP_PIXELS, skippixels);

   glPixelStorei(GL_UNPACK_ALIGNMENT, alignment);

}

#endif