tests/spec/ext_frag_depth/fragdepth.c

   1 /*
   2  * Copyright 2017 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
  24 /**
  25  * Test GL_EXT_frag_depth support in GLSL ES 1.0
  26  * We draw overlapping red and green quads.  The red quad is at Z=0
  27  * while the green quad's fragment depths vary from left to right.
  28  * Should see intersecting quads.
  29  */
  30
  31
  32 #include "piglit-util-gl.h"
  33
  34 PIGLIT_GL_TEST_CONFIG_BEGIN
  35         config.supports_gl_es_version = 20;
  36         config.window_visual = (PIGLIT_GL_VISUAL_RGBA |
  37                                 PIGLIT_GL_VISUAL_DEPTH |
  38                                 PIGLIT_GL_VISUAL_DOUBLE);
  39 PIGLIT_GL_TEST_CONFIG_END
  40
  41
  42 static const char *vs_source =
  43         "#version 100 \n"
  44         "attribute vec4 piglit_vertex;\n"
  45         "varying float z; \n"
  46         "void main() { \n"
  47         "   gl_Position = piglit_vertex; \n"
  48         "   // Convert z from [-1, 1] to [0, 1] \n"
  49         "   z = piglit_vertex.x * 0.5 + 0.5; \n"
  50         "}\n";
  51 static const char *fs_source =
  52         "#version 100 \n"
  53         "#extension GL_EXT_frag_depth : enable \n"
  54         "precision mediump float; \n"
  55         "varying float z; \n"
  56         "uniform vec4 color;\n"
  57         "void main() { \n"
  58         "   if (color.g == 1.0) \n"
  59         "         gl_FragDepthEXT = z; \n"
  60         "   else \n"
  61         "         gl_FragDepthEXT = 0.5; \n"
  62         "   gl_FragColor = color; \n"
  63         "}\n";
  64
  65 static GLuint program;
  66
  67
  68 enum piglit_result
  69 piglit_display(void)
  70 {
  71         static const float red[4] = {1.0, 0.0, 0.0, 1.0};
  72         static const float green[4] = {0.0, 1.0, 0.0, 1.0};
  73         int x = piglit_width / 2;
  74         int y = piglit_height / 2;
  75         bool pass = true;
  76         int color_loc;
  77
  78         glViewport(0, 0, piglit_width, piglit_height);
  79         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  80         glUseProgram(program);
  81         color_loc = glGetUniformLocation(program, "color");
  82
  83         glUniform4fv(color_loc, 1, red);
  84         /* Draw a red rect at z = 0 (will be 0.5 in depth range [0,1]) */
  85         piglit_draw_rect(-0.5, -0.5, 1.0, 1.0);
  86
  87         /* Draw green rect with variable z = piglit_vertex.x * 0.5 + 0.5 */
  88         glUniform4fv(color_loc, 1, green);
  89         piglit_draw_rect(-0.75, -0.25, 1.5, 0.5);
  90
  91         pass = piglit_probe_pixel_rgba(x-10, y, green) && pass;
  92         pass = piglit_probe_pixel_rgba(x+10, y, red) && pass;
  93
  94         piglit_present_results();
  95         return pass ? PIGLIT_PASS : PIGLIT_FAIL;
  96 }
  97
  98
  99 void
 100 piglit_init(int argc, char **argv)
 101 {
 102         piglit_require_extension("GL_EXT_frag_depth");
 103         program = piglit_build_simple_program(vs_source, fs_source);
 104         glClearColor(0.25f, 0.25f, 0.25f, 1.0f);
 105         glEnable(GL_DEPTH_TEST);
 106 }