src/mesa/main/formatquery.c

   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
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 #include "mtypes.h"
  25 #include "context.h"
  26 #include "glformats.h"
  27 #include "macros.h"
  28 #include "mfeatures.h"
  29 #include "enums.h"
  30 #include "fbobject.h"
  31 #include "formatquery.h"
  32
  33 void GLAPIENTRY
  34 _mesa_GetInternalformativ(GLenum target, GLenum internalformat, GLenum pname,
  35                           GLsizei bufSize, GLint *params)
  36 {
  37    GLint buffer[16];
  38    GLsizei count = 0;
  39    GET_CURRENT_CONTEXT(ctx);
  40
  41    ASSERT_OUTSIDE_BEGIN_END(ctx);
  42
  43    if (!ctx->Extensions.ARB_internalformat_query) {
  44       _mesa_error(ctx, GL_INVALID_OPERATION, "glGetInternalformativ");
  45       return;
  46    }
  47
  48    assert(ctx->Driver.QuerySamplesForFormat != NULL);
  49
  50    /* The ARB_internalformat_query spec says:
  51     *
  52     *     "If the <target> parameter to GetInternalformativ is not one of
  53     *     TEXTURE_2D_MULTISAMPLE, TEXTURE_2D_MULTISAMPLE_ARRAY or RENDERBUFFER
  54     *     then an INVALID_ENUM error is generated."
  55     */
  56    switch (target) {
  57    case GL_RENDERBUFFER:
  58       break;
  59
  60    case GL_TEXTURE_2D_MULTISAMPLE:
  61    case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
  62       /* Mesa does not currently support GL_ARB_texture_multisample, so these
  63        * enums are not valid on this implementation either.
  64        */
  65    default:
  66       _mesa_error(ctx, GL_INVALID_ENUM,
  67                   "glGetInternalformativ(target=%s)",
  68                   _mesa_lookup_enum_by_nr(target));
  69       return;
  70    }
  71
  72    /* The ARB_internalformat_query spec says:
  73     *
  74     *     "If the <internalformat> parameter to GetInternalformativ is not
  75     *     color-, depth- or stencil-renderable, then an INVALID_ENUM error is
  76     *     generated."
  77     */
  78    if (_mesa_base_fbo_format(ctx, internalformat) == 0) {
  79       _mesa_error(ctx, GL_INVALID_ENUM,
  80                   "glGetInternalformativ(internalformat=%s)",
  81                   _mesa_lookup_enum_by_nr(internalformat));
  82       return;
  83    }
  84
  85    /* The ARB_internalformat_query spec says:
  86     *
  87     *     "If the <bufSize> parameter to GetInternalformativ is negative, then
  88     *     an INVALID_VALUE error is generated."
  89     */
  90    if (bufSize < 0) {
  91       _mesa_error(ctx, GL_INVALID_VALUE,
  92                   "glGetInternalformativ(target=%s)",
  93                   _mesa_lookup_enum_by_nr(target));
  94       return;
  95    }
  96
  97    switch (pname) {
  98    case GL_SAMPLES:
  99       count = ctx->Driver.QuerySamplesForFormat(ctx, internalformat, buffer);
 100       break;
 101    case GL_NUM_SAMPLE_COUNTS: {
 102       /* The driver can return 0, and we should pass that along to the
 103        * application.  The ARB decided that ARB_internalformat_query should
 104        * behave as ARB_internalformat_query2 in this situation.
 105        *
 106        * The ARB_internalformat_query2 spec says:
 107        *
 108        *     "- NUM_SAMPLE_COUNTS: The number of sample counts that would be
 109        *        returned by querying SAMPLES is returned in <params>.
 110        *        * If <internalformat> is not color-renderable,
 111        *          depth-renderable, or stencil-renderable (as defined in
 112        *          section 4.4.4), or if <target> does not support multiple
 113        *          samples (ie other than TEXTURE_2D_MULTISAMPLE,
 114        *          TEXTURE_2D_MULTISAMPLE_ARRAY, or RENDERBUFFER), 0 is
 115        *          returned."
 116        */
 117       const size_t num_samples =
 118          ctx->Driver.QuerySamplesForFormat(ctx, internalformat, buffer);
 119
 120       /* QuerySamplesForFormat writes some stuff to buffer, so we have to
 121        * separately over-write it with the requested value.
 122        */
 123       buffer[0] = (GLint) num_samples;
 124       count = 1;
 125       break;
 126    }
 127    default:
 128       _mesa_error(ctx, GL_INVALID_ENUM,
 129                   "glGetInternalformativ(pname=%s)",
 130                   _mesa_lookup_enum_by_nr(pname));
 131       return;
 132    }
 133
 134    if (bufSize != 0 && params == NULL) {
 135       /* Emit a warning to aid application debugging, but go ahead and do the
 136        * memcpy (and probably crash) anyway.
 137        */
 138       _mesa_warning(ctx,
 139                     "glGetInternalformativ(bufSize = %d, but params = NULL)",
 140                     bufSize);
 141    }
 142
 143    /* Copy the data from the temporary buffer to the buffer supplied by the
 144     * application.  Clamp the size of the copy to the size supplied by the
 145     * application.
 146     */
 147    memcpy(params, buffer, MIN2(count, bufSize) * sizeof(GLint));
 148
 149    return;
 150 }