1 /*
2 * Copyright © 2012 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 /**
25 * \file enable-flag.cpp
26 *
27 * This test verifies the proper functioning of the GL_MULTISAMPLE
28 * flag. From the GL 3.0 spec (p.116):
29 *
30 * "Multisample rasterization is enabled or disabled by calling
31 * Enable or Disable with the symbolic constant MULTISAMPLE."
32 *
33 * Elsewhere in the spec, where multisample rasterization is described
34 * (sections 3.4.3, 3.5.4, and 3.6.6), the following text is
35 * consistently used:
36 *
37 * "If MULTISAMPLE is enabled, and the value of SAMPLE_BUFFERS is
38 * one, then..."
39 *
40 * So, in other words, disabling GL_MULTISAMPLE should prevent
41 * multisample rasterization from occurring, even if the draw
42 * framebuffer is multisampled.
43 *
44 *
45 * This test operates by performing the following operations:
46 *
47 * 1. Verify that the default state of GL_MULTISAMPLE is enabled.
48 *
49 * 2. Draw a test image into a multisampled buffer, with
50 * GL_MULTISAMPLE disabled.
51 *
52 * 3. Blit this image to the left half of the piglit window (which is
53 * not multisampled) to resolve it.
54 *
55 * 4. Draw the same test image into a single-sampled buffer.
56 *
57 * 5. Blit this image to the right half of the piglit window.
58 *
59 * 6. Verify that the two halves of the piglit window match. If they
60 * don't, then presumably the disabling of GL_MULTISAMPLE failed to
61 * take effect.
62 */
63
64 #include "piglit-test-pattern.h"
65 #include "piglit-fbo.h"
66 using namespace piglit_util_fbo;
67 using namespace piglit_util_test_pattern;
68
69 PIGLIT_GL_TEST_CONFIG_BEGIN
70
71 config.supports_gl_compat_version = 10;
72
73 config.window_width = 512;
74 config.window_height = 256;
75 config.window_visual = PIGLIT_GL_VISUAL_DOUBLE | PIGLIT_GL_VISUAL_RGBA;
76 config.khr_no_error_support = PIGLIT_NO_ERRORS;
77
78 PIGLIT_GL_TEST_CONFIG_END
79
80 namespace {
81
82 const int pattern_width = 256; const int pattern_height = 256;
83
84 Fbo singlesampled_fbo;
85 Fbo multisampled_fbo;
86 Triangles triangles;
87
88 extern "C" void
piglit_init(int argc,char ** argv)89 piglit_init(int argc, char **argv)
90 {
91 piglit_require_gl_version(21);
92 piglit_require_extension("GL_ARB_framebuffer_object");
93 piglit_require_extension("GL_ARB_vertex_array_object");
94
95 GLint max_samples;
96 glGetIntegerv(GL_MAX_SAMPLES, &max_samples);
97
98 singlesampled_fbo.setup(FboConfig(0, pattern_width,
99 pattern_height));
100 multisampled_fbo.setup(FboConfig(max_samples, pattern_width,
101 pattern_height));
102 triangles.compile();
103 }
104
105 extern "C" enum piglit_result
piglit_display()106 piglit_display()
107 {
108 bool pass = true;
109
110 glBindFramebuffer(GL_DRAW_FRAMEBUFFER, piglit_winsys_fbo);
111 glViewport(0, 0, piglit_width, piglit_height);
112 glClear(GL_COLOR_BUFFER_BIT);
113
114 /* Verify that the default state of GL_MULTISAMPLE is
115 * enabled.
116 */
117 pass = glIsEnabled(GL_MULTISAMPLE) && pass;
118
119 /* Draw a test image into a multisampled buffer, with
120 * GL_MULTISAMPLE disabled.
121 */
122 glBindFramebuffer(GL_DRAW_FRAMEBUFFER, multisampled_fbo.handle);
123 multisampled_fbo.set_viewport();
124 glDisable(GL_MULTISAMPLE);
125 triangles.draw(TestPattern::no_projection);
126 glEnable(GL_MULTISAMPLE);
127
128 /* Blit this image to the left half of the piglit window
129 * (which is not multisampled) to resolve it.
130 */
131 glBindFramebuffer(GL_READ_FRAMEBUFFER, multisampled_fbo.handle);
132 glBindFramebuffer(GL_DRAW_FRAMEBUFFER, piglit_winsys_fbo);
133 glBlitFramebuffer(0, 0, pattern_width, pattern_height,
134 0, 0, pattern_width, pattern_height,
135 GL_COLOR_BUFFER_BIT, GL_NEAREST);
136
137 /* Draw the same test image into a single-sampled buffer. */
138 glBindFramebuffer(GL_DRAW_FRAMEBUFFER, singlesampled_fbo.handle);
139 singlesampled_fbo.set_viewport();
140 triangles.draw(TestPattern::no_projection);
141
142 /* Blit this image to the right half of the piglit window. */
143 glBindFramebuffer(GL_READ_FRAMEBUFFER, singlesampled_fbo.handle);
144 glBindFramebuffer(GL_DRAW_FRAMEBUFFER, piglit_winsys_fbo);
145 glBlitFramebuffer(0, 0, pattern_width, pattern_height,
146 pattern_width, 0, 2*pattern_width, pattern_height,
147 GL_COLOR_BUFFER_BIT, GL_NEAREST);
148
149 /* Verify that the two halves of the piglit window match. If
150 * they don't, then presumably the disabling of GL_MULTISAMPLE
151 * failed to take effect.
152 */
153 glBindFramebuffer(GL_READ_FRAMEBUFFER, piglit_winsys_fbo);
154 pass = piglit_probe_rect_halves_equal_rgba(0, 0, 2*pattern_width,
155 pattern_height) && pass;
156
157 piglit_present_results();
158
159 return pass ? PIGLIT_PASS : PIGLIT_FAIL;
160 }
161
162 } /* Anonymous namespace */
163