src/mesa/main/multisample.c

   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
  40 _mesa_SampleCoverage(GLclampf value, GLboolean invert)
  41 {
  42    GET_CURRENT_CONTEXT(ctx);
  43
  44    value = CLAMP(value, 0.0f, 1.0f);
  45
  46    if (ctx->Multisample.SampleCoverageInvert == invert &&
  47        ctx->Multisample.SampleCoverageValue == value)
  48       return;
  49
  50    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewSampleMask ? 0 : _NEW_MULTISAMPLE);
  51    ctx->NewDriverState |= ctx->DriverFlags.NewSampleMask;
  52    ctx->Multisample.SampleCoverageValue = value;
  53    ctx->Multisample.SampleCoverageInvert = invert;
  54 }
  55
  56
  57 /**
  58  * Initialize the context's multisample state.
  59  * \param ctx  the GL context.
  60  */
  61 void
  62 _mesa_init_multisample(struct gl_context *ctx)
  63 {
  64    ctx->Multisample.Enabled = GL_TRUE;
  65    ctx->Multisample.SampleAlphaToCoverage = GL_FALSE;
  66    ctx->Multisample.SampleAlphaToOne = GL_FALSE;
  67    ctx->Multisample.SampleCoverage = GL_FALSE;
  68    ctx->Multisample.SampleCoverageValue = 1.0;
  69    ctx->Multisample.SampleCoverageInvert = GL_FALSE;
  70    ctx->Multisample.SampleShading = GL_FALSE;
  71    ctx->Multisample.MinSampleShadingValue = 0.0f;
  72
  73    /* ARB_texture_multisample / GL3.2 additions */
  74    ctx->Multisample.SampleMask = GL_FALSE;
  75    ctx->Multisample.SampleMaskValue = ~(GLbitfield)0;
  76 }
  77
  78
  79 void GLAPIENTRY
  80 _mesa_GetMultisamplefv(GLenum pname, GLuint index, GLfloat * val)
  81 {
  82    GET_CURRENT_CONTEXT(ctx);
  83
  84    if (ctx->NewState & _NEW_BUFFERS) {
  85       _mesa_update_state(ctx);
  86    }
  87
  88    switch (pname) {
  89    case GL_SAMPLE_POSITION: {
  90       if ((int) index >= ctx->DrawBuffer->Visual.samples) {
  91          _mesa_error( ctx, GL_INVALID_VALUE, "glGetMultisamplefv(index)" );
  92          return;
  93       }
  94
  95       ctx->Driver.GetSamplePosition(ctx, ctx->DrawBuffer, index, val);
  96
  97       /* winsys FBOs are upside down */
  98       if (_mesa_is_winsys_fbo(ctx->DrawBuffer))
  99          val[1] = 1.0f - val[1];
 100
 101       return;
 102    }
 103
 104    default:
 105       _mesa_error( ctx, GL_INVALID_ENUM, "glGetMultisamplefv(pname)" );
 106       return;
 107    }
 108 }
 109
 110 static void
 111 sample_maski(struct gl_context *ctx, GLuint index, GLbitfield mask)
 112 {
 113    if (ctx->Multisample.SampleMaskValue == mask)
 114       return;
 115
 116    FLUSH_VERTICES(ctx, ctx->DriverFlags.NewSampleMask ? 0 : _NEW_MULTISAMPLE);
 117    ctx->NewDriverState |= ctx->DriverFlags.NewSampleMask;
 118    ctx->Multisample.SampleMaskValue = mask;
 119 }
 120
 121 void GLAPIENTRY
 122 _mesa_SampleMaski_no_error(GLuint index, GLbitfield mask)
 123 {
 124    GET_CURRENT_CONTEXT(ctx);
 125    sample_maski(ctx, index, mask);
 126 }
 127
 128 void GLAPIENTRY
 129 _mesa_SampleMaski(GLuint index, GLbitfield mask)
 130 {
 131    GET_CURRENT_CONTEXT(ctx);
 132
 133    if (!ctx->Extensions.ARB_texture_multisample) {
 134       _mesa_error(ctx, GL_INVALID_OPERATION, "glSampleMaski");
 135       return;
 136    }
 137
 138    if (index != 0) {
 139       _mesa_error(ctx, GL_INVALID_VALUE, "glSampleMaski(index)");
 140       return;
 141    }
 142
 143    sample_maski(ctx, index, mask);
 144 }
 145
 146 static void
 147 min_sample_shading(struct gl_context *ctx, GLclampf value)
 148 {
 149    value = CLAMP(value, 0.0f, 1.0f);
 150
 151    if (ctx->Multisample.MinSampleShadingValue == value)
 152       return;
 153
 154    FLUSH_VERTICES(ctx,
 155                   ctx->DriverFlags.NewSampleShading ? 0 : _NEW_MULTISAMPLE);
 156    ctx->NewDriverState |= ctx->DriverFlags.NewSampleShading;
 157    ctx->Multisample.MinSampleShadingValue = value;
 158 }
 159
 160 /**
 161  * Called via glMinSampleShadingARB
 162  */
 163 void GLAPIENTRY
 164 _mesa_MinSampleShading_no_error(GLclampf value)
 165 {
 166    GET_CURRENT_CONTEXT(ctx);
 167    min_sample_shading(ctx, value);
 168 }
 169
 170 void GLAPIENTRY
 171 _mesa_MinSampleShading(GLclampf value)
 172 {
 173    GET_CURRENT_CONTEXT(ctx);
 174
 175    if (!_mesa_has_ARB_sample_shading(ctx) &&
 176        !_mesa_has_OES_sample_shading(ctx)) {
 177       _mesa_error(ctx, GL_INVALID_OPERATION, "glMinSampleShading");
 178       return;
 179    }
 180
 181    min_sample_shading(ctx, value);
 182 }
 183
 184 /**
 185  * Helper for checking a requested sample count against the limit
 186  * for a particular (target, internalFormat) pair. The limit imposed,
 187  * and the error generated, both depend on which extensions are supported.
 188  *
 189  * Returns a GL error enum, or GL_NO_ERROR if the requested sample count is
 190  * acceptable.
 191  */
 192 GLenum
 193 _mesa_check_sample_count(struct gl_context *ctx, GLenum target,
 194                          GLenum internalFormat, GLsizei samples)
 195 {
 196    /* Section 4.4 (Framebuffer objects), page 198 of the OpenGL ES 3.0.0
 197     * specification says:
 198     *
 199     *     "If internalformat is a signed or unsigned integer format and samples
 200     *     is greater than zero, then the error INVALID_OPERATION is generated."
 201     *
 202     * This restriction is relaxed for OpenGL ES 3.1.
 203     */
 204    if ((ctx->API == API_OPENGLES2 && ctx->Version == 30) &&
 205        _mesa_is_enum_format_integer(internalFormat)
 206        && samples > 0) {
 207       return GL_INVALID_OPERATION;
 208    }
 209
 210    /* If ARB_internalformat_query is supported, then treat its highest
 211     * returned sample count as the absolute maximum for this format; it is
 212     * allowed to exceed MAX_SAMPLES.
 213     *
 214     * From the ARB_internalformat_query spec:
 215     *
 216     * "If <samples is greater than the maximum number of samples supported
 217     * for <internalformat> then the error INVALID_OPERATION is generated."
 218     */
 219    if (ctx->Extensions.ARB_internalformat_query) {
 220       GLint buffer[16] = {-1};
 221       GLint limit;
 222
 223       ctx->Driver.QueryInternalFormat(ctx, target, internalFormat,
 224                                       GL_SAMPLES, buffer);
 225       /* since the query returns samples sorted in descending order,
 226        * the first element is the greatest supported sample value.
 227        */
 228       limit = buffer[0];
 229
 230       return samples > limit ? GL_INVALID_OPERATION : GL_NO_ERROR;
 231    }
 232
 233    /* If ARB_texture_multisample is supported, we have separate limits,
 234     * which may be lower than MAX_SAMPLES:
 235     *
 236     * From the ARB_texture_multisample spec, when describing the operation
 237     * of RenderbufferStorageMultisample:
 238     *
 239     * "If <internalformat> is a signed or unsigned integer format and
 240     * <samples> is greater than the value of MAX_INTEGER_SAMPLES, then the
 241     * error INVALID_OPERATION is generated"
 242     *
 243     * And when describing the operation of TexImage*Multisample:
 244     *
 245     * "The error INVALID_OPERATION may be generated if any of the following
 246     * are true:
 247     *
 248     * * <internalformat> is a depth/stencil-renderable format and <samples>
 249     *   is greater than the value of MAX_DEPTH_TEXTURE_SAMPLES
 250     * * <internalformat> is a color-renderable format and <samples> is
 251     *   grater than the value of MAX_COLOR_TEXTURE_SAMPLES
 252     * * <internalformat> is a signed or unsigned integer format and
 253     *   <samples> is greater than the value of MAX_INTEGER_SAMPLES
 254     */
 255
 256    if (ctx->Extensions.ARB_texture_multisample) {
 257       if (_mesa_is_enum_format_integer(internalFormat))
 258          return samples > ctx->Const.MaxIntegerSamples
 259             ? GL_INVALID_OPERATION : GL_NO_ERROR;
 260
 261       if (target == GL_TEXTURE_2D_MULTISAMPLE ||
 262           target == GL_TEXTURE_2D_MULTISAMPLE_ARRAY) {
 263
 264          if (_mesa_is_depth_or_stencil_format(internalFormat))
 265             return samples > ctx->Const.MaxDepthTextureSamples
 266                ? GL_INVALID_OPERATION : GL_NO_ERROR;
 267          else
 268             return samples > ctx->Const.MaxColorTextureSamples
 269                ? GL_INVALID_OPERATION : GL_NO_ERROR;
 270       }
 271    }
 272
 273    /* No more specific limit is available, so just use MAX_SAMPLES:
 274     *
 275     * On p205 of the GL3.1 spec:
 276     *
 277     * "... or if samples is greater than MAX_SAMPLES, then the error
 278     * INVALID_VALUE is generated"
 279     */
 280    return (GLuint) samples > ctx->Const.MaxSamples
 281       ? GL_INVALID_VALUE : GL_NO_ERROR;
 282 }