1 /*
2 * Copyright © 2015 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
24 /** @file read-depth.c
25 *
26 * Tests NV_read_depth implementation
27 *
28 * Test iterates over table of depth buffer formats and expected types to
29 * read values back from each format. For each format it renders a rectangle at
30 * different depth levels, reads back a pixel and verifies expected depth value.
31 */
32
33 #include "piglit-util-gl.h"
34
35 PIGLIT_GL_TEST_CONFIG_BEGIN
36
37 config.supports_gl_es_version = 30;
38 config.window_visual = PIGLIT_GL_VISUAL_DEPTH;
39
40 PIGLIT_GL_TEST_CONFIG_END
41
42 static GLint prog;
43
44 const char *vs_source =
45 "attribute vec4 vertex;\n"
46 "uniform float depth;\n"
47 "void main()\n"
48 "{\n"
49 " gl_Position = vec4(vertex.xy, depth, 1.0);\n"
50 "}\n";
51
52 const char *fs_source =
53 "void main()\n"
54 "{\n"
55 "}\n";
56
57 const GLenum tests[] = {
58 GL_DEPTH_COMPONENT16, GL_UNSIGNED_INT_24_8_OES,
59 GL_DEPTH_COMPONENT24, GL_UNSIGNED_INT_24_8_OES,
60 GL_DEPTH_COMPONENT32F, GL_FLOAT,
61 };
62
63 static bool
equals(float a,float b)64 equals(float a, float b)
65 {
66 return fabs(a - b) < 0.00001;
67 }
68
69 static GLuint
create_depth_fbo(GLenum depth_type)70 create_depth_fbo(GLenum depth_type)
71 {
72 GLuint fbo, buffer;
73 GLenum status;
74
75 glGenRenderbuffers(1, &buffer);
76 glBindRenderbuffer(GL_RENDERBUFFER, buffer);
77 glRenderbufferStorage(GL_RENDERBUFFER,
78 depth_type, piglit_width, piglit_height);
79
80 glGenFramebuffers(1, &fbo);
81 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
82
83 glFramebufferRenderbuffer(GL_FRAMEBUFFER,
84 GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, buffer);
85
86 status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
87 if (status != GL_FRAMEBUFFER_COMPLETE) {
88 fprintf(stderr, "error creating framebuffer, status 0x%x\n",
89 status);
90 return 0;
91 }
92 return fbo;
93 }
94
95 static bool
read_depth(GLenum type,float expect)96 read_depth(GLenum type, float expect)
97 {
98 GLfloat data;
99 GLuint uint_pixel;
100 if (type == GL_FLOAT) {
101 glReadPixels(0, 0, 1, 1, GL_DEPTH_COMPONENT, type,
102 (void *) &data);
103 } else {
104 glReadPixels(0, 0, 1, 1, GL_DEPTH_COMPONENT, type,
105 (void *) &uint_pixel);
106 uint_pixel = uint_pixel >> 8;
107 data = (1.0 * ((float) uint_pixel)) / 16777215.0;
108 }
109
110 if (!piglit_check_gl_error(GL_NO_ERROR))
111 return false;
112
113 if (!equals(data, expect)) {
114 fprintf(stderr, "expected %f, got %f\n", expect, data);
115 return false;
116 }
117 return true;
118 }
119
120 enum piglit_result
piglit_display(void)121 piglit_display(void)
122 {
123 const float step = 0.1;
124 unsigned j;
125 float i;
126
127 glEnable(GL_DEPTH_TEST);
128 glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
129
130 /* Loop through formats listed in 'tests'. */
131 for (j = 0; j < ARRAY_SIZE(tests); j += 2) {
132
133 float expect = 0.0;
134
135 GLuint fbo = create_depth_fbo(tests[j]);
136 if (!fbo)
137 return PIGLIT_FAIL;
138
139 /* Step from -1.0 to 1.0, linear depth. Render a rectangle at
140 * depth i, read pixel and verify expected depth value.
141 */
142 for (i = -1.0; !equals(i, 1.0 + step); i += step) {
143
144 glClear(GL_DEPTH_BUFFER_BIT);
145 glUniform1f(glGetUniformLocation(prog, "depth"), i);
146
147 piglit_draw_rect(-1, -1, 2, 2);
148
149 if (!(read_depth(tests[j + 1], expect)))
150 return PIGLIT_FAIL;
151
152 expect += step / 2.0;
153 }
154 glDeleteFramebuffers(1, &fbo);
155 }
156 return PIGLIT_PASS;
157 }
158
159 void
piglit_init(int argc,char ** argv)160 piglit_init(int argc, char **argv)
161 {
162 piglit_require_extension("GL_NV_read_depth");
163 prog = piglit_build_simple_program(vs_source, fs_source);
164 glUseProgram(prog);
165 }
166