tests/general/scissor-depth-clear.c

   1 /*
   2  * Copyright © 2009 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  *
  26  */
  27
  28 /** @file scissor-copypixels.c
  29  *
  30  * Tests that glScissor properly affects glClear(GL_DEPTH_BUFFER_BIT).
  31  */
  32
  33 #include "piglit-util.h"
  34
  35 int piglit_width = 100, piglit_height = 100;
  36 int piglit_window_mode = GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH | GLUT_STENCIL;
  37
  38 enum piglit_result
  39 piglit_display(void)
  40 {
  41         GLboolean pass = GL_TRUE;
  42         int x, y;
  43         static float green[] = {0.0, 1.0, 0.0, 0.0};
  44         static float blue[]  = {0.0, 0.0, 1.0, 0.0};
  45
  46         /* whole window green -- depth fail will be this. */
  47         glClearColor(0.0, 1.0, 0.0, 0.0);
  48         glClear(GL_COLOR_BUFFER_BIT);
  49
  50         /* Clear depth to 0 (fail) */
  51         glClearDepth(0.0);
  52         glClear(GL_DEPTH_BUFFER_BIT);
  53
  54         /* Clear depth quad at 10, 10 to be drawn blue. */
  55         glEnable(GL_SCISSOR_TEST);
  56         glScissor(10, 10, 10, 10);
  57         glClearDepth(1.0);
  58         glClear(GL_DEPTH_BUFFER_BIT);
  59
  60         /* Clear a 0x0 depth quad a 10, 30 that shouldn't be drawn. */
  61         glScissor(10, 30, 0, 0);
  62         glClearDepth(1.0);
  63         glClear(GL_DEPTH_BUFFER_BIT);
  64
  65         /* Now draw a quad midway between 0.0 and 1.0 depth so only that
  66          * scissored depth clear will get rasterized.
  67          */
  68         glEnable(GL_DEPTH_TEST);
  69         glDisable(GL_SCISSOR_TEST);
  70         glDepthFunc(GL_LESS);
  71         glColor4fv(blue);
  72         piglit_draw_rect(0, 0, piglit_width, piglit_height);
  73
  74         for (y = 0; y < piglit_height; y++) {
  75                 for (x = 0; x < piglit_width; x++) {
  76                         float *expected;
  77
  78                         if (x >= 10 && x < 20 && y >= 10 && y < 20)
  79                                 expected = blue;
  80                         else
  81                                 expected = green;
  82
  83                         pass &= piglit_probe_pixel_rgb(x, y, expected);
  84                 }
  85         }
  86
  87         glutSwapBuffers();
  88
  89         return pass ? PIGLIT_SUCCESS : PIGLIT_FAILURE;
  90 }
  91
  92
  93 static void reshape(int width, int height)
  94 {
  95         piglit_width = width;
  96         piglit_height = height;
  97
  98         glViewport(0, 0, width, height);
  99         glMatrixMode(GL_PROJECTION);
 100         glLoadIdentity();
 101
 102         glOrtho(0.0, width, 0.0, height, -1.0, 1.0);
 103         glMatrixMode(GL_MODELVIEW);
 104         glLoadIdentity();
 105 }
 106
 107 void
 108 piglit_init(int argc, char **argv)
 109 {
 110         reshape(piglit_width, piglit_height);
 111 }