tests/general/depth-clamp-range.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
  21  * DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  */
  26
  27 /** @file depth-clamp-range.c
  28  *
  29  * Tests that ARB_depth_clamp enablement didn't break DepthRange functionality,
  30  * and properly uses the min/max selection.
  31  */
  32
  33 #include "piglit-util.h"
  34
  35 int piglit_width = 150, piglit_height = 150;
  36 int piglit_window_mode = GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH;
  37
  38 /* In case the headers have the old enum name but not the new */
  39 #ifndef GL_DEPTH_CLAMP
  40 #define GL_DEPTH_CLAMP GL_DEPTH_CLAMP_NV
  41 #endif
  42
  43 void
  44 piglit_init(int argc, char **argv)
  45 {
  46         piglit_require_extension("GL_ARB_depth_clamp");
  47
  48         piglit_ortho_projection(piglit_width, piglit_height, GL_FALSE);
  49 }
  50
  51 void
  52 quad(float base_x, float base_y, float z)
  53 {
  54         glBegin(GL_QUADS);
  55         glVertex3f(base_x,      base_y,      z);
  56         glVertex3f(base_x + 10, base_y,      z);
  57         glVertex3f(base_x + 10, base_y + 10, z);
  58         glVertex3f(base_x,      base_y + 10, z);
  59         glEnd();
  60 }
  61
  62 enum piglit_result
  63 piglit_display(void)
  64 {
  65         GLboolean pass = GL_TRUE;
  66         float white[3] = {1.0, 1.0, 1.0};
  67         float clear[3] = {0.0, 0.0, 0.0};
  68
  69         glClearDepth(0.5);
  70         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  71         glEnable(GL_DEPTH_TEST);
  72         glDepthFunc(GL_LEQUAL);
  73
  74         glColor4fv(white);
  75
  76         /* Keep in mind that the ortho projection flips near and far's signs,
  77          * so 1.0 to quad()'s z maps to glDepthRange's near, and -1.0 maps to
  78          * glDepthRange's far.
  79          */
  80
  81         /* Basic glDepthRange testing. */
  82         glDisable(GL_DEPTH_CLAMP);
  83         glDepthRange(0, 1);
  84         quad(10, 10, 0.5); /* .25 - drawn. */
  85
  86         glDepthRange(1, 0);
  87         quad(10, 30, 0.5); /* 0.75 - not drawn. */
  88
  89         /* Now, test that near depth clamping works.*/
  90         glEnable(GL_DEPTH_CLAMP);
  91         glDepthRange(0.25, 1.0);
  92         quad(30, 10, 2); /* 0.25 - drawn. */
  93
  94         glDepthRange(0.75, 1.0);
  95         quad(30, 30, 2); /* 0.75 - not drawn. */
  96
  97         /* Test that far clamping works.*/
  98         glDepthRange(0.0, 0.25);
  99         quad(50, 10, -2); /* 0.25 - drawn. */
 100
 101         glDepthRange(0.0, 0.75);
 102         quad(50, 30, -2); /* 0.75 - not drawn. */
 103
 104         /* Now, flip near and far around and make sure that it's doing the
 105          * min/max of near and far in the clamping.
 106          */
 107
 108         /* Test that near (max) clamping works. */
 109         glDepthRange(0.25, 0.0);
 110         quad(70, 10, 2); /* 0.25 - drawn. */
 111
 112         glDepthRange(0.75, 0.0);
 113         quad(70, 30, 2); /* 0.75 - not drawn. */
 114
 115         /* Now, test far (min) clamping works. */
 116         glDepthRange(1.0, 0.0);
 117         quad(90, 10, -2); /* 0.0 - drawn */
 118
 119         glDepthRange(1.0, 0.75);
 120         quad(90, 30, -2); /* 0.75 - not drawn*/
 121
 122         pass = piglit_probe_pixel_rgb(15, 15, white) && pass;
 123         pass = piglit_probe_pixel_rgb(15, 35, clear) && pass;
 124         pass = piglit_probe_pixel_rgb(35, 15, white) && pass;
 125         pass = piglit_probe_pixel_rgb(35, 35, clear) && pass;
 126         pass = piglit_probe_pixel_rgb(55, 15, white) && pass;
 127         pass = piglit_probe_pixel_rgb(55, 35, clear) && pass;
 128         pass = piglit_probe_pixel_rgb(75, 15, white) && pass;
 129         pass = piglit_probe_pixel_rgb(75, 35, clear) && pass;
 130         pass = piglit_probe_pixel_rgb(95, 15, white) && pass;
 131         pass = piglit_probe_pixel_rgb(95, 35, clear) && pass;
 132
 133         glutSwapBuffers();
 134
 135         return pass ? PIGLIT_SUCCESS : PIGLIT_FAILURE;
 136 }