1 /*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR 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
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25
26 #include "main/glheader.h"
27 #include "main/context.h"
28 #include "main/macros.h"
29 #include "main/multisample.h"
30 #include "main/mtypes.h"
31 #include "main/fbobject.h"
32 #include "main/glformats.h"
33 #include "main/state.h"
34
35
36 /**
37 * Called via glSampleCoverageARB
38 */
39 void GLAPIENTRY
_mesa_SampleCoverage(GLclampf value,GLboolean invert)40 _mesa_SampleCoverage(GLclampf value, GLboolean invert)
41 {
42 GET_CURRENT_CONTEXT(ctx);
43
44 FLUSH_VERTICES(ctx, 0);
45
46 ctx->Multisample.SampleCoverageValue = CLAMP(value, 0.0f, 1.0f);
47 ctx->Multisample.SampleCoverageInvert = invert;
48 ctx->NewState |= _NEW_MULTISAMPLE;
49 }
50
51
52 /**
53 * Initialize the context's multisample state.
54 * \param ctx the GL context.
55 */
56 void
_mesa_init_multisample(struct gl_context * ctx)57 _mesa_init_multisample(struct gl_context *ctx)
58 {
59 ctx->Multisample.Enabled = GL_TRUE;
60 ctx->Multisample.SampleAlphaToCoverage = GL_FALSE;
61 ctx->Multisample.SampleAlphaToOne = GL_FALSE;
62 ctx->Multisample.SampleCoverage = GL_FALSE;
63 ctx->Multisample.SampleCoverageValue = 1.0;
64 ctx->Multisample.SampleCoverageInvert = GL_FALSE;
65
66 /* ARB_texture_multisample / GL3.2 additions */
67 ctx->Multisample.SampleMask = GL_FALSE;
68 ctx->Multisample.SampleMaskValue = ~(GLbitfield)0;
69 }
70
71
72 void GLAPIENTRY
_mesa_GetMultisamplefv(GLenum pname,GLuint index,GLfloat * val)73 _mesa_GetMultisamplefv(GLenum pname, GLuint index, GLfloat * val)
74 {
75 GET_CURRENT_CONTEXT(ctx);
76
77 if (ctx->NewState & _NEW_BUFFERS) {
78 _mesa_update_state(ctx);
79 }
80
81 switch (pname) {
82 case GL_SAMPLE_POSITION: {
83 if ((int) index >= ctx->DrawBuffer->Visual.samples) {
84 _mesa_error( ctx, GL_INVALID_VALUE, "glGetMultisamplefv(index)" );
85 return;
86 }
87
88 ctx->Driver.GetSamplePosition(ctx, ctx->DrawBuffer, index, val);
89
90 /* winsys FBOs are upside down */
91 if (_mesa_is_winsys_fbo(ctx->DrawBuffer))
92 val[1] = 1.0f - val[1];
93
94 return;
95 }
96
97 default:
98 _mesa_error( ctx, GL_INVALID_ENUM, "glGetMultisamplefv(pname)" );
99 return;
100 }
101 }
102
103 void GLAPIENTRY
_mesa_SampleMaski(GLuint index,GLbitfield mask)104 _mesa_SampleMaski(GLuint index, GLbitfield mask)
105 {
106 GET_CURRENT_CONTEXT(ctx);
107
108 if (!ctx->Extensions.ARB_texture_multisample) {
109 _mesa_error(ctx, GL_INVALID_OPERATION, "glSampleMaski");
110 return;
111 }
112
113 if (index != 0) {
114 _mesa_error(ctx, GL_INVALID_VALUE, "glSampleMaski(index)");
115 return;
116 }
117
118 FLUSH_VERTICES(ctx, _NEW_MULTISAMPLE);
119 ctx->Multisample.SampleMaskValue = mask;
120 }
121
122 /**
123 * Called via glMinSampleShadingARB
124 */
125 void GLAPIENTRY
_mesa_MinSampleShading(GLclampf value)126 _mesa_MinSampleShading(GLclampf value)
127 {
128 GET_CURRENT_CONTEXT(ctx);
129
130 if (!_mesa_has_ARB_sample_shading(ctx) &&
131 !_mesa_has_OES_sample_shading(ctx)) {
132 _mesa_error(ctx, GL_INVALID_OPERATION, "glMinSampleShading");
133 return;
134 }
135
136 FLUSH_VERTICES(ctx, 0);
137
138 ctx->Multisample.MinSampleShadingValue = CLAMP(value, 0.0f, 1.0f);
139 ctx->NewState |= _NEW_MULTISAMPLE;
140 }
141
142 /**
143 * Helper for checking a requested sample count against the limit
144 * for a particular (target, internalFormat) pair. The limit imposed,
145 * and the error generated, both depend on which extensions are supported.
146 *
147 * Returns a GL error enum, or GL_NO_ERROR if the requested sample count is
148 * acceptable.
149 */
150 GLenum
_mesa_check_sample_count(struct gl_context * ctx,GLenum target,GLenum internalFormat,GLsizei samples)151 _mesa_check_sample_count(struct gl_context *ctx, GLenum target,
152 GLenum internalFormat, GLsizei samples)
153 {
154 /* Section 4.4 (Framebuffer objects), page 198 of the OpenGL ES 3.0.0
155 * specification says:
156 *
157 * "If internalformat is a signed or unsigned integer format and samples
158 * is greater than zero, then the error INVALID_OPERATION is generated."
159 *
160 * This restriction is relaxed for OpenGL ES 3.1.
161 */
162 if ((ctx->API == API_OPENGLES2 && ctx->Version == 30) &&
163 _mesa_is_enum_format_integer(internalFormat)
164 && samples > 0) {
165 return GL_INVALID_OPERATION;
166 }
167
168 /* If ARB_internalformat_query is supported, then treat its highest
169 * returned sample count as the absolute maximum for this format; it is
170 * allowed to exceed MAX_SAMPLES.
171 *
172 * From the ARB_internalformat_query spec:
173 *
174 * "If <samples is greater than the maximum number of samples supported
175 * for <internalformat> then the error INVALID_OPERATION is generated."
176 */
177 if (ctx->Extensions.ARB_internalformat_query) {
178 GLint buffer[16] = {-1};
179 GLint limit;
180
181 ctx->Driver.QueryInternalFormat(ctx, target, internalFormat,
182 GL_SAMPLES, buffer);
183 /* since the query returns samples sorted in descending order,
184 * the first element is the greatest supported sample value.
185 */
186 limit = buffer[0];
187
188 return samples > limit ? GL_INVALID_OPERATION : GL_NO_ERROR;
189 }
190
191 /* If ARB_texture_multisample is supported, we have separate limits,
192 * which may be lower than MAX_SAMPLES:
193 *
194 * From the ARB_texture_multisample spec, when describing the operation
195 * of RenderbufferStorageMultisample:
196 *
197 * "If <internalformat> is a signed or unsigned integer format and
198 * <samples> is greater than the value of MAX_INTEGER_SAMPLES, then the
199 * error INVALID_OPERATION is generated"
200 *
201 * And when describing the operation of TexImage*Multisample:
202 *
203 * "The error INVALID_OPERATION may be generated if any of the following
204 * are true:
205 *
206 * * <internalformat> is a depth/stencil-renderable format and <samples>
207 * is greater than the value of MAX_DEPTH_TEXTURE_SAMPLES
208 * * <internalformat> is a color-renderable format and <samples> is
209 * grater than the value of MAX_COLOR_TEXTURE_SAMPLES
210 * * <internalformat> is a signed or unsigned integer format and
211 * <samples> is greater than the value of MAX_INTEGER_SAMPLES
212 */
213
214 if (ctx->Extensions.ARB_texture_multisample) {
215 if (_mesa_is_enum_format_integer(internalFormat))
216 return samples > ctx->Const.MaxIntegerSamples
217 ? GL_INVALID_OPERATION : GL_NO_ERROR;
218
219 if (target == GL_TEXTURE_2D_MULTISAMPLE ||
220 target == GL_TEXTURE_2D_MULTISAMPLE_ARRAY) {
221
222 if (_mesa_is_depth_or_stencil_format(internalFormat))
223 return samples > ctx->Const.MaxDepthTextureSamples
224 ? GL_INVALID_OPERATION : GL_NO_ERROR;
225 else
226 return samples > ctx->Const.MaxColorTextureSamples
227 ? GL_INVALID_OPERATION : GL_NO_ERROR;
228 }
229 }
230
231 /* No more specific limit is available, so just use MAX_SAMPLES:
232 *
233 * On p205 of the GL3.1 spec:
234 *
235 * "... or if samples is greater than MAX_SAMPLES, then the error
236 * INVALID_VALUE is generated"
237 */
238 return (GLuint) samples > ctx->Const.MaxSamples
239 ? GL_INVALID_VALUE : GL_NO_ERROR;
240 }
241