/*
* Copyright © 2014 Intel Corporation
*
* 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 (including the next
* paragraph) 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.
*/
#include "brw_meta_util.h"
#include "main/fbobject.h"
/**
* Helper function for handling mirror image blits.
*
* If coord0 > coord1, swap them and invert the "mirror" boolean.
*/
static inline void
fixup_mirroring(bool *mirror, float *coord0, float *coord1)
{
if (*coord0 > *coord1) {
*mirror = !*mirror;
float tmp = *coord0;
*coord0 = *coord1;
*coord1 = tmp;
}
}
/**
* Adjust {src,dst}_x{0,1} to account for clipping and scissoring of
* destination coordinates.
*
* Return true if there is still blitting to do, false if all pixels got
* rejected by the clip and/or scissor.
*
* For clarity, the nomenclature of this function assumes we are clipping and
* scissoring the X coordinate; the exact same logic applies for Y
* coordinates.
*
* Note: this function may also be used to account for clipping of source
* coordinates, by swapping the roles of src and dst.
*/
static inline bool
clip_or_scissor(bool mirror,
GLfloat *src_x0, GLfloat *src_x1,
GLfloat *dst_x0, GLfloat *dst_x1,
GLfloat fb_xmin, GLfloat fb_xmax)
{
float scale = (float) (*src_x1 - *src_x0) / (*dst_x1 - *dst_x0);
/* If we are going to scissor everything away, stop. */
if (!(fb_xmin < fb_xmax &&
*dst_x0 < fb_xmax &&
fb_xmin < *dst_x1 &&
*dst_x0 < *dst_x1)) {
return false;
}
/* Clip the destination rectangle, and keep track of how many pixels we
* clipped off of the left and right sides of it.
*/
int pixels_clipped_left = 0;
int pixels_clipped_right = 0;
if (*dst_x0 < fb_xmin) {
pixels_clipped_left = fb_xmin - *dst_x0;
*dst_x0 = fb_xmin;
}
if (fb_xmax < *dst_x1) {
pixels_clipped_right = *dst_x1 - fb_xmax;
*dst_x1 = fb_xmax;
}
/* If we are mirrored, then before applying pixels_clipped_{left,right} to
* the source coordinates, we need to flip them to account for the
* mirroring.
*/
if (mirror) {
int tmp = pixels_clipped_left;
pixels_clipped_left = pixels_clipped_right;
pixels_clipped_right = tmp;
}
/* Adjust the source rectangle to remove the pixels corresponding to those
* that were clipped/scissored out of the destination rectangle.
*/
*src_x0 += pixels_clipped_left * scale;
*src_x1 -= pixels_clipped_right * scale;
return true;
}
bool
brw_meta_mirror_clip_and_scissor(const struct gl_context *ctx,
const struct gl_framebuffer *read_fb,
const struct gl_framebuffer *draw_fb,
GLfloat *srcX0, GLfloat *srcY0,
GLfloat *srcX1, GLfloat *srcY1,
GLfloat *dstX0, GLfloat *dstY0,
GLfloat *dstX1, GLfloat *dstY1,
bool *mirror_x, bool *mirror_y)
{
*mirror_x = false;
*mirror_y = false;
/* Detect if the blit needs to be mirrored */
fixup_mirroring(mirror_x, srcX0, srcX1);
fixup_mirroring(mirror_x, dstX0, dstX1);
fixup_mirroring(mirror_y, srcY0, srcY1);
fixup_mirroring(mirror_y, dstY0, dstY1);
/* If the destination rectangle needs to be clipped or scissored, do so. */
if (!(clip_or_scissor(*mirror_x, srcX0, srcX1, dstX0, dstX1,
draw_fb->_Xmin, draw_fb->_Xmax) &&
clip_or_scissor(*mirror_y, srcY0, srcY1, dstY0, dstY1,
draw_fb->_Ymin, draw_fb->_Ymax))) {
/* Everything got clipped/scissored away, so the blit was successful. */
return true;
}
/* If the source rectangle needs to be clipped or scissored, do so. */
if (!(clip_or_scissor(*mirror_x, dstX0, dstX1, srcX0, srcX1,
0, read_fb->Width) &&
clip_or_scissor(*mirror_y, dstY0, dstY1, srcY0, srcY1,
0, read_fb->Height))) {
/* Everything got clipped/scissored away, so the blit was successful. */
return true;
}
/* Account for the fact that in the system framebuffer, the origin is at
* the lower left.
*/
if (_mesa_is_winsys_fbo(read_fb)) {
GLint tmp = read_fb->Height - *srcY0;
*srcY0 = read_fb->Height - *srcY1;
*srcY1 = tmp;
*mirror_y = !*mirror_y;
}
if (_mesa_is_winsys_fbo(draw_fb)) {
GLint tmp = draw_fb->Height - *dstY0;
*dstY0 = draw_fb->Height - *dstY1;
*dstY1 = tmp;
*mirror_y = !*mirror_y;
}
return false;
}