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       /* These enums are only valid if ARB_texture_multisample is supported */
  63       if (_mesa_is_desktop_gl(ctx) && ctx->Extensions.ARB_texture_multisample)
  64          break;
  65
  66    default:
  67       _mesa_error(ctx, GL_INVALID_ENUM,
  68                   "glGetInternalformativ(target=%s)",
  69                   _mesa_lookup_enum_by_nr(target));
  70       return;
  71    }
  72
  73    /* The ARB_internalformat_query spec says:
  74     *
  75     *     "If the <internalformat> parameter to GetInternalformativ is not
  76     *     color-, depth- or stencil-renderable, then an INVALID_ENUM error is
  77     *     generated."
  78     */
  79    if (_mesa_base_fbo_format(ctx, internalformat) == 0) {
  80       _mesa_error(ctx, GL_INVALID_ENUM,
  81                   "glGetInternalformativ(internalformat=%s)",
  82                   _mesa_lookup_enum_by_nr(internalformat));
  83       return;
  84    }
  85
  86    /* The ARB_internalformat_query spec says:
  87     *
  88     *     "If the <bufSize> parameter to GetInternalformativ is negative, then
  89     *     an INVALID_VALUE error is generated."
  90     */
  91    if (bufSize < 0) {
  92       _mesa_error(ctx, GL_INVALID_VALUE,
  93                   "glGetInternalformativ(target=%s)",
  94                   _mesa_lookup_enum_by_nr(target));
  95       return;
  96    }
  97
  98    switch (pname) {
  99    case GL_SAMPLES:
 100       count = ctx->Driver.QuerySamplesForFormat(ctx, target,
 101             internalformat, buffer);
 102       break;
 103    case GL_NUM_SAMPLE_COUNTS: {
 104       /* The driver can return 0, and we should pass that along to the
 105        * application.  The ARB decided that ARB_internalformat_query should
 106        * behave as ARB_internalformat_query2 in this situation.
 107        *
 108        * The ARB_internalformat_query2 spec says:
 109        *
 110        *     "- NUM_SAMPLE_COUNTS: The number of sample counts that would be
 111        *        returned by querying SAMPLES is returned in <params>.
 112        *        * If <internalformat> is not color-renderable,
 113        *          depth-renderable, or stencil-renderable (as defined in
 114        *          section 4.4.4), or if <target> does not support multiple
 115        *          samples (ie other than TEXTURE_2D_MULTISAMPLE,
 116        *          TEXTURE_2D_MULTISAMPLE_ARRAY, or RENDERBUFFER), 0 is
 117        *          returned."
 118        */
 119       const size_t num_samples =
 120          ctx->Driver.QuerySamplesForFormat(ctx, target, internalformat, buffer);
 121
 122       /* QuerySamplesForFormat writes some stuff to buffer, so we have to
 123        * separately over-write it with the requested value.
 124        */
 125       buffer[0] = (GLint) num_samples;
 126       count = 1;
 127       break;
 128    }
 129    default:
 130       _mesa_error(ctx, GL_INVALID_ENUM,
 131                   "glGetInternalformativ(pname=%s)",
 132                   _mesa_lookup_enum_by_nr(pname));
 133       return;
 134    }
 135
 136    if (bufSize != 0 && params == NULL) {
 137       /* Emit a warning to aid application debugging, but go ahead and do the
 138        * memcpy (and probably crash) anyway.
 139        */
 140       _mesa_warning(ctx,
 141                     "glGetInternalformativ(bufSize = %d, but params = NULL)",
 142                     bufSize);
 143    }
 144
 145    /* Copy the data from the temporary buffer to the buffer supplied by the
 146     * application.  Clamp the size of the copy to the size supplied by the
 147     * application.
 148     */
 149    memcpy(params, buffer, MIN2(count, bufSize) * sizeof(GLint));
 150
 151    return;
 152 }