tests/shaders/glsl-fs-pointcoord.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 glsl-fs-pointcoord.c
  29  *
  30  * Tests that gl_PointCoord produces the expected output in a fragment shader
  31  * with point sprites enabled.
  32  */
  33
  34 #include <assert.h>
  35 #include <string.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <errno.h>
  39 #include <sys/stat.h>
  40 #define GL_GLEXT_PROTOTYPES
  41 #include <GL/glew.h>
  42 #if defined(__APPLE__)
  43 #include <GLUT/glut.h>
  44 #else
  45 #include "GL/glut.h"
  46 #endif
  47
  48 #include "piglit-util.h"
  49
  50 int piglit_width = 256;
  51 int piglit_height = 256;
  52 int piglit_window_mode = GLUT_DOUBLE | GLUT_RGB;
  53
  54 static GLint prog;
  55 static GLint point_size;
  56
  57 enum piglit_result
  58 piglit_display(void)
  59 {
  60         GLboolean pass = GL_TRUE;
  61         const float red[4] =    {1, 0, 0, 0};
  62         const float green[4] =  {0, 1, 0, 0};
  63         const float yellow[4] = {1, 1, 0, 0};
  64         const float black[4] =  {0, 0, 0, 0};
  65
  66         piglit_ortho_projection(piglit_width, piglit_height, GL_FALSE);
  67
  68         glClearColor(0.5, 0.5, 0.5, 0.5);
  69         glClear(GL_COLOR_BUFFER_BIT);
  70
  71         glPointSize(point_size);
  72         glBegin(GL_POINTS);
  73         glVertex2f(point_size / 2, point_size / 2);
  74         glEnd();
  75
  76         pass = pass && piglit_probe_pixel_rgb(0, 0, green);
  77         pass = pass && piglit_probe_pixel_rgb(point_size - 1, 0, yellow);
  78         pass = pass && piglit_probe_pixel_rgb(0, point_size - 1, black);
  79         pass = pass && piglit_probe_pixel_rgb(point_size - 1, point_size - 1, red);
  80
  81         glutSwapBuffers();
  82
  83         return pass ? PIGLIT_SUCCESS : PIGLIT_FAILURE;
  84 }
  85
  86 void piglit_init(int argc, char**argv)
  87 {
  88         GLint vs, fs;
  89         GLint point_size_limits[2];
  90
  91         if (!GLEW_VERSION_2_0) {
  92                 printf("Requires OpenGL 2.0\n");
  93                 piglit_report_result(PIGLIT_SKIP);
  94                 exit(1);
  95         }
  96         piglit_require_extension("GL_ARB_point_sprite");
  97
  98         glGetIntegerv(GL_ALIASED_POINT_SIZE_RANGE, point_size_limits);
  99         point_size = point_size_limits[1];
 100         if (point_size > piglit_width)
 101            point_size = piglit_width;
 102
 103         if (point_size > piglit_width)
 104                 point_size = piglit_width;
 105         if (point_size > piglit_height)
 106                 point_size = piglit_height;
 107
 108         vs = piglit_compile_shader(GL_VERTEX_SHADER,
 109                                    "shaders/glsl-fs-pointcoord.vert");
 110         fs = piglit_compile_shader(GL_FRAGMENT_SHADER,
 111                                    "shaders/glsl-fs-pointcoord.frag");
 112
 113         prog = piglit_link_simple_program(vs, fs);
 114
 115         glEnable(GL_POINT_SPRITE);
 116
 117         glUseProgram(prog);
 118 }