tests/shaders/glsl-fs-fragcoord-zw-ortho.c

   1 /*
   2  * Copyright © 2009 Intel Corporation
   3  * Copyright © 2011 VMware, Inc.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  22  * IN THE SOFTWARE.
  23  *
  24  * Authors:
  25  *    Eric Anholt <eric@anholt.net>
  26  *    Brian Paul
  27  *
  28  */
  29
  30 /** @file glsl-fs-fragcoord-zw-ortho.c
  31  *
  32  * Tests that gl_FragCoord.zw produces the expected output in a fragment shader
  33  * with an orthographic projection
  34  */
  35
  36 #include "piglit-util-gl.h"
  37
  38 PIGLIT_GL_TEST_CONFIG_BEGIN
  39
  40         config.supports_gl_compat_version = 10;
  41
  42         config.window_width = 256;
  43         config.window_height = 256;
  44         config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DOUBLE | PIGLIT_GL_VISUAL_DEPTH;
  45         config.khr_no_error_support = PIGLIT_NO_ERRORS;
  46
  47 PIGLIT_GL_TEST_CONFIG_END
  48
  49 static void
  50 draw_quad(float x, float y, float w, float h)
  51 {
  52         float zLeft = -1.0, zRight = 1.0;
  53         float verts[4][4];
  54
  55         verts[0][0] = x;
  56         verts[0][1] = y;
  57         verts[0][2] = zLeft;
  58         verts[0][3] = 1.0;
  59         verts[1][0] = x + w;
  60         verts[1][1] = y;
  61         verts[1][2] = zRight;
  62         verts[1][3] = 1.0;
  63         verts[2][0] = x + w;
  64         verts[2][1] = y + h;
  65         verts[2][2] = zRight;
  66         verts[2][3] = 1.0;
  67         verts[3][0] = x;
  68         verts[3][1] = y + h;
  69         verts[3][2] = zLeft;
  70         verts[3][3] = 1.0;
  71
  72         glVertexPointer(4, GL_FLOAT, 0, verts);
  73         glEnableClientState(GL_VERTEX_ARRAY);
  74
  75         glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
  76
  77         glDisableClientState(GL_VERTEX_ARRAY);
  78 }
  79
  80
  81
  82 enum piglit_result
  83 piglit_display(void)
  84 {
  85         GLboolean pass = GL_TRUE;
  86         int x, y;
  87
  88         glClearColor(0.5, 0.5, 0.5, 0.5);
  89         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  90
  91         draw_quad(0, 0, piglit_width, piglit_height);
  92
  93         /* Test Z values */
  94         pass = piglit_probe_pixel_depth(0, 0, 1.0) && pass;
  95         pass = piglit_probe_pixel_depth(piglit_width-1, 0, 0.0) && pass;
  96         pass = piglit_probe_pixel_depth(piglit_width-1, piglit_height-1, 0.0) && pass;
  97         pass = piglit_probe_pixel_depth(0, piglit_height-1, 1.0) && pass;
  98
  99         /* Test colors */
 100         for (y = 8; y < piglit_height && pass; y += 16) {
 101                 for (x = 8; x < piglit_width; x += 16) {
 102                         float color[3];
 103
 104                         color[0] = 1.0 - x / 256.0;  /* gl_FragCoord.z */
 105                         color[1] = 1.0;              /* gl_FragCoord.w */
 106                         color[2] = 0;
 107
 108                         pass &= piglit_probe_pixel_rgb(x, y, color);
 109                         if (!pass)
 110                                 break;
 111                 }
 112         }
 113
 114         piglit_present_results();
 115
 116         return pass ? PIGLIT_PASS : PIGLIT_FAIL;
 117 }
 118
 119 void
 120 piglit_init(int argc, char **argv)
 121 {
 122         GLint vs, fs, prog;
 123
 124         piglit_require_gl_version(20);
 125
 126         piglit_ortho_projection(piglit_width, piglit_height, GL_FALSE);
 127
 128         vs = piglit_compile_shader(GL_VERTEX_SHADER,
 129                                    "shaders/glsl-mvp.vert");
 130         fs = piglit_compile_shader(GL_FRAGMENT_SHADER,
 131                                    "shaders/glsl-fs-fragcoord-zw.frag");
 132
 133         prog = piglit_link_simple_program(vs, fs);
 134
 135         glUseProgram(prog);
 136
 137         glEnable(GL_DEPTH_TEST);
 138 }