tests/fast_color_clear/read-to-pbo-after-clear.c

   1 /*
   2  * Copyright © 2013 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
  24 /**
  25  * \file read-to-pbo-after-clear.c
  26  *
  27  * On i965/gen7+, glReadPixels uses the hardware blitter when reading
  28  * from the window system buffer to a PBO, provided that no format
  29  * conversions need to be performed.  This test verifies that fast
  30  * color clears are properly resolved before this blit occurs.
  31  *
  32  * The test operates by painting the window system framebuffer red
  33  * using a non-fast-clear technique (rendering a quad using a shader),
  34  * and then clearing it to green using a fast clear.  Then it reads
  35  * from the window to a PBO using glReadPixels(), and then maps the
  36  * PBO into CPU memory and verifies that it contains green.
  37  */
  38
  39 #include "piglit-util-gl.h"
  40
  41 #define TEX_WIDTH 512
  42 #define TEX_HEIGHT 512
  43
  44 PIGLIT_GL_TEST_CONFIG_BEGIN
  45         config.supports_gl_compat_version = 11;
  46         config.window_width = TEX_WIDTH;
  47         config.window_height = TEX_HEIGHT;
  48         config.window_visual = PIGLIT_GL_VISUAL_DOUBLE | PIGLIT_GL_VISUAL_RGBA;
  49         config.khr_no_error_support = PIGLIT_NO_ERRORS;
  50 PIGLIT_GL_TEST_CONFIG_END
  51
  52
  53 static const char *vs_text =
  54         "void main()\n"
  55         "{\n"
  56         "  gl_Position = gl_Vertex;\n"
  57         "  gl_TexCoord[0] = gl_MultiTexCoord0;\n"
  58         "}\n";
  59
  60 static const char *fs_text_paint_red =
  61         "void main()\n"
  62         "{\n"
  63         "  gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);\n"
  64         "}\n";
  65
  66 static const char *fs_text_sample =
  67         "uniform sampler2D samp;\n"
  68         "void main()\n"
  69         "{\n"
  70         "  gl_FragColor = texture2D(samp, gl_TexCoord[0].xy);\n"
  71         "}\n";
  72
  73 static GLuint prog_paint_red, prog_sample, pbo;
  74
  75
  76 void
  77 piglit_init(int argc, char **argv)
  78 {
  79         GLuint vs, fs_paint_red, fs_sample;
  80
  81         /* Requirements */
  82         piglit_require_gl_version(11);
  83         piglit_require_GLSL_version(110);
  84         piglit_require_extension("GL_ARB_pixel_buffer_object");
  85
  86         /* Compile shaders */
  87         vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vs_text);
  88         fs_paint_red = piglit_compile_shader_text(GL_FRAGMENT_SHADER,
  89                                                   fs_text_paint_red);
  90         prog_paint_red = piglit_link_simple_program(vs, fs_paint_red);
  91         if (!prog_paint_red)
  92                 piglit_report_result(PIGLIT_FAIL);
  93         fs_sample = piglit_compile_shader_text(GL_FRAGMENT_SHADER,
  94                                                fs_text_sample);
  95         prog_sample = piglit_link_simple_program(vs, fs_sample);
  96         if (!prog_sample)
  97                 piglit_report_result(PIGLIT_FAIL);
  98         if (!piglit_check_gl_error(GL_NO_ERROR))
  99                 piglit_report_result(PIGLIT_FAIL);
 100
 101         /* Set up PBO */
 102         glGenBuffers(1, &pbo);
 103         glBindBuffer(GL_PIXEL_PACK_BUFFER, pbo);
 104         glBufferData(GL_PIXEL_PACK_BUFFER, 4 * TEX_WIDTH * TEX_HEIGHT, NULL,
 105                      GL_STREAM_READ);
 106         glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
 107
 108         if (!piglit_check_gl_error(GL_NO_ERROR))
 109                 piglit_report_result(PIGLIT_FAIL);
 110 }
 111
 112
 113 bool
 114 check_pbo_data(const GLubyte *expected)
 115 {
 116         int i, j, k;
 117         const GLubyte *data = glMapBuffer(GL_PIXEL_PACK_BUFFER, GL_READ_ONLY);
 118         for (i = 0; i < TEX_HEIGHT; i++) {
 119                 for (j = 0; j < TEX_WIDTH; j++) {
 120                         const GLubyte *actual = &data[(i * TEX_WIDTH + j) * 4];
 121                         for (k = 0; k < 4; k++) {
 122                                 if (actual[k] != expected[k]) {
 123                                         printf("Failure at (%d, %d):\n"
 124                                                "Expected BGRA %d, %d, %d, %d\n"
 125                                                "Got BGRA %d, %d, %d, %d\n",
 126                                                i, j,
 127                                                expected[0], expected[1],
 128                                                expected[2], expected[3],
 129                                                actual[0], actual[1],
 130                                                actual[2], actual[3]);
 131                                         glUnmapBuffer(GL_PIXEL_PACK_BUFFER);
 132                                         return false;
 133                                 }
 134                         }
 135                 }
 136         }
 137         glUnmapBuffer(GL_PIXEL_PACK_BUFFER);
 138         return true;
 139 }
 140
 141
 142 enum piglit_result
 143 piglit_display(void)
 144 {
 145         bool pass = true;
 146         static const GLubyte green_ubytes[] = { 0, 255, 0, 255 };
 147
 148         /* Paint the window red using a shader (not a fast clear). */
 149         glUseProgram(prog_paint_red);
 150         glViewport(0, 0, TEX_WIDTH, TEX_HEIGHT);
 151         piglit_draw_rect(-1, -1, 2, 2);
 152
 153         /* Clear the window to green; this will be optimized using a
 154          * fast color clear if the hardware is capable of it.
 155          */
 156         glClearColor(0, 1, 0, 1);
 157         glClear(GL_COLOR_BUFFER_BIT);
 158
 159         /* Read directly from the window into a PBO using
 160          * glReadPixels().  Note: we read using GL_UNSIGNED_BYTE and
 161          * GL_BGRA since that's the case that causes the i965 driver
 162          * to perform the read using a blit.
 163          */
 164         glBindBuffer(GL_PIXEL_PACK_BUFFER, pbo);
 165         glReadPixels(0, 0, TEX_WIDTH, TEX_HEIGHT, GL_BGRA,
 166                      GL_UNSIGNED_BYTE, NULL);
 167         pass = check_pbo_data(green_ubytes) && pass;
 168
 169         /* Note: piglit_present_results() will force a resolve to
 170          * occur, so even if the test has failed, the window might
 171          * appear green.  To avoid confusing the user, clear the
 172          * window to black before calling piglit_present_results().
 173          */
 174         glClearColor(0, 0, 0, 1);
 175         glClear(GL_COLOR_BUFFER_BIT);
 176
 177         if (!piglit_check_gl_error(GL_NO_ERROR))
 178                 pass = false;
 179
 180         piglit_present_results();
 181         return pass ? PIGLIT_PASS : PIGLIT_FAIL;
 182 }