tests/spec/arb_texture_stencil8/draw.c

   1 /*
   2  * Copyright © 2014 Intel Corporation
   3  * Copyright © 2015 Red Hat
   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
  25 /**
  26  * \file draw.c
  27  *
  28  * A basic drawing test for GL_ARB_texture_stencil8 which ensures that
  29  * sampling occurs from the right position in the texture.
  30  *
  31  * It creates two stencil textures.  The first has a horizontal
  32  * gradient (0 -> 255 for stencil), and the second a
  33  * vertical gradient.
  34  *
  35  * The expected output is two squares, separated by a blue border.
  36  * The left half of the window is generated by stencil texturing, and drawn
  37  * in red.
  38  *
  39  *   Stencil
  40  *    (red)
  41  *
  42  *   0 --> 1
  43  *  --------
  44  *      1
  45  *      ^
  46  *      |
  47  *      0
  48  */
  49
  50 #define __STDC_FORMAT_MACROS
  51 #include <inttypes.h>
  52 #include "piglit-util-gl.h"
  53
  54 PIGLIT_GL_TEST_CONFIG_BEGIN
  55
  56         config.supports_gl_core_version = 32;
  57         config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DOUBLE;
  58         config.khr_no_error_support = PIGLIT_NO_ERRORS;
  59         config.window_width = 256 + 3;
  60         config.window_height = 256 * 2 + 3;
  61
  62 PIGLIT_GL_TEST_CONFIG_END
  63
  64 float stencil_horiz_expected[256 * 256 * 3];
  65 float stencil_vert_expected[256 * 256 * 3];
  66
  67 GLuint horiz_tex;
  68 GLuint vert_tex;
  69
  70 /** A program that samples from stencil using usampler2D. */
  71 GLint stencil_prog;
  72
  73 GLuint vao;
  74
  75 /******************************************************************************/
  76
  77 enum piglit_result
  78 piglit_display(void)
  79 {
  80         bool pass = true;
  81
  82         glClearColor(0.0, 0.0, 1.0, 1.0);
  83         glClear(GL_COLOR_BUFFER_BIT);
  84
  85         glUseProgram(stencil_prog);
  86
  87         /* Upper left corner: Stencil (black to red, left to right). */
  88         glViewport(0, 259, 256, 256);
  89         glBindTexture(GL_TEXTURE_2D, horiz_tex);
  90         piglit_draw_rect(-1, -1, 2, 2);
  91         if (!piglit_probe_image_rgb(0, 259, 256, 256, stencil_horiz_expected)) {
  92                 printf("  FAIL: stencil (horizontal).\n");
  93                 pass = false;
  94         }
  95
  96
  97         /* Lower left corner: Stencil (black to red, upwards). */
  98         glViewport(0, 0, 256, 256);
  99         glBindTexture(GL_TEXTURE_2D, vert_tex);
 100         piglit_draw_rect(-1, -1, 2, 2);
 101         if (!piglit_probe_image_rgb(0, 0, 256, 256, stencil_vert_expected)) {
 102                 printf("  FAIL: stencil (vertical).\n");
 103                 pass = false;
 104         }
 105
 106         piglit_present_results();
 107
 108         return pass ? PIGLIT_PASS : PIGLIT_FAIL;
 109 }
 110
 111 /******************************************************************************/
 112
 113 /*
 114  * - Stencil ranges from 0 to 255.
 115  *
 116  * horiz_tex is left to right (increasing in the +x direction);
 117  * vert_tex is bottom to top (increasing in the +y direction).
 118  *
 119  * Also set up expected values.
 120  */
 121 static void
 122 setup_textures(void)
 123 {
 124         int i;
 125         uint8_t horiz_data[256 * 256];
 126         uint8_t vert_data[256 * 256];
 127
 128         for (i = 0; i < ARRAY_SIZE(horiz_data); i++) {
 129                 unsigned x = i % 256;
 130                 unsigned y = i / 256;
 131                 horiz_data[i] = x;
 132                 vert_data[i] = y;
 133         }
 134
 135         glGenTextures(1, &horiz_tex);
 136         glBindTexture(GL_TEXTURE_2D, horiz_tex);
 137         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 138         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 139         glTexImage2D(GL_TEXTURE_2D, 0, GL_STENCIL_INDEX8,
 140                      256, 256, 0, GL_STENCIL_INDEX, GL_UNSIGNED_BYTE,
 141                      horiz_data);
 142         if (!piglit_check_gl_error(GL_NO_ERROR))
 143                 piglit_report_result(PIGLIT_FAIL);
 144
 145         glGenTextures(1, &vert_tex);
 146         glBindTexture(GL_TEXTURE_2D, vert_tex);
 147         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 148         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 149         glTexImage2D(GL_TEXTURE_2D, 0, GL_STENCIL_INDEX8,
 150                      256, 256, 0, GL_STENCIL_INDEX, GL_UNSIGNED_BYTE,
 151                      vert_data);
 152         if (!piglit_check_gl_error(GL_NO_ERROR))
 153                 piglit_report_result(PIGLIT_FAIL);
 154
 155         /* Set up expected values. */
 156         memset(stencil_horiz_expected, 0, sizeof(stencil_horiz_expected));
 157         memset(stencil_vert_expected, 0, sizeof(stencil_vert_expected));
 158
 159         for (i = 0; i < 256 * 256; i++) {
 160                 unsigned x = i % 256;
 161                 unsigned y = i / 256;
 162                 stencil_horiz_expected[3*i] = x / 255.0f;
 163                 stencil_vert_expected[3*i]  = y / 255.0f;
 164         }
 165
 166
 167 }
 168
 169 /**
 170  * Compile the shaders used by this program.
 171  *
 172  */
 173 static void
 174 setup_shaders(void)
 175 {
 176         int loc;
 177
 178         const char *vs =
 179         "#version 130\n"
 180         "in vec4 piglit_vertex;\n"
 181         "out vec2 texcoords;\n"
 182         "void main()\n"
 183         "{\n"
 184         "    gl_Position = piglit_vertex;\n"
 185         "    texcoords = (piglit_vertex.xy + 1.0) / 2.0;\n"
 186         "}\n";
 187
 188         const char *fs_stencil =
 189         "#version 130\n"
 190         "in vec2 texcoords;\n"
 191         "uniform usampler2D tex;\n"
 192         "void main()\n"
 193         "{\n"
 194         "    uint stencil = texture(tex, texcoords).x;\n"
 195         "    gl_FragColor = vec4(float(stencil) / 255.0, 0, 0, 1);\n"
 196         "}\n";
 197
 198         stencil_prog = piglit_build_simple_program(vs, fs_stencil);
 199         loc = glGetUniformLocation(stencil_prog, "tex");
 200         glUseProgram(stencil_prog);
 201         glUniform1i(loc, 0);
 202
 203 }
 204
 205 void
 206 piglit_init(int argc, char **argv)
 207 {
 208         piglit_require_extension("GL_ARB_texture_stencil8");
 209
 210         glGenVertexArrays(1, &vao);
 211         glBindVertexArray(vao);
 212         setup_textures();
 213         setup_shaders();
 214 }