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 "enums.h"
  29 #include "fbobject.h"
  30 #include "formatquery.h"
  31
  32 /* default implementation of QuerySamplesForFormat driverfunc, for
  33  * non-multisample-capable drivers. */
  34 size_t
  35 _mesa_query_samples_for_format(struct gl_context *ctx, GLenum target,
  36                                GLenum internalFormat, int samples[16])
  37 {
  38    (void) target;
  39    (void) internalFormat;
  40    (void) ctx;
  41
  42    samples[0] = 1;
  43    return 1;
  44 }
  45
  46
  47 void GLAPIENTRY
  48 _mesa_GetInternalformativ(GLenum target, GLenum internalformat, GLenum pname,
  49                           GLsizei bufSize, GLint *params)
  50 {
  51    GLint buffer[16];
  52    GLsizei count = 0;
  53    GET_CURRENT_CONTEXT(ctx);
  54
  55    ASSERT_OUTSIDE_BEGIN_END(ctx);
  56
  57    if (!ctx->Extensions.ARB_internalformat_query) {
  58       _mesa_error(ctx, GL_INVALID_OPERATION, "glGetInternalformativ");
  59       return;
  60    }
  61
  62    assert(ctx->Driver.QuerySamplesForFormat != NULL);
  63
  64    /* The ARB_internalformat_query spec says:
  65     *
  66     *     "If the <target> parameter to GetInternalformativ is not one of
  67     *     TEXTURE_2D_MULTISAMPLE, TEXTURE_2D_MULTISAMPLE_ARRAY or RENDERBUFFER
  68     *     then an INVALID_ENUM error is generated."
  69     */
  70    switch (target) {
  71    case GL_RENDERBUFFER:
  72       break;
  73
  74    case GL_TEXTURE_2D_MULTISAMPLE:
  75    case GL_TEXTURE_2D_MULTISAMPLE_ARRAY:
  76       /* These enums are only valid if ARB_texture_multisample is supported */
  77       if ((_mesa_is_desktop_gl(ctx) &&
  78            ctx->Extensions.ARB_texture_multisample) ||
  79           _mesa_is_gles31(ctx))
  80          break;
  81
  82    default:
  83       _mesa_error(ctx, GL_INVALID_ENUM,
  84                   "glGetInternalformativ(target=%s)",
  85                   _mesa_enum_to_string(target));
  86       return;
  87    }
  88
  89    /* The ARB_internalformat_query spec says:
  90     *
  91     *     "If the <internalformat> parameter to GetInternalformativ is not
  92     *     color-, depth- or stencil-renderable, then an INVALID_ENUM error is
  93     *     generated."
  94     *
  95     * Page 243 of the GLES 3.0.4 spec says this for GetInternalformativ:
  96     *
  97     *     "internalformat must be color-renderable, depth-renderable or
  98     *     stencilrenderable (as defined in section 4.4.4)."
  99     *
 100     * Section 4.4.4 on page 212 of the same spec says:
 101     *
 102     *     "An internal format is color-renderable if it is one of the
 103     *     formats from table 3.13 noted as color-renderable or if it
 104     *     is unsized format RGBA or RGB."
 105     *
 106     * Therefore, we must accept GL_RGB and GL_RGBA here.
 107     */
 108    if (internalformat != GL_RGB && internalformat != GL_RGBA &&
 109        _mesa_base_fbo_format(ctx, internalformat) == 0) {
 110       _mesa_error(ctx, GL_INVALID_ENUM,
 111                   "glGetInternalformativ(internalformat=%s)",
 112                   _mesa_enum_to_string(internalformat));
 113       return;
 114    }
 115
 116    /* The ARB_internalformat_query spec says:
 117     *
 118     *     "If the <bufSize> parameter to GetInternalformativ is negative, then
 119     *     an INVALID_VALUE error is generated."
 120     */
 121    if (bufSize < 0) {
 122       _mesa_error(ctx, GL_INVALID_VALUE,
 123                   "glGetInternalformativ(target=%s)",
 124                   _mesa_enum_to_string(target));
 125       return;
 126    }
 127
 128    switch (pname) {
 129    case GL_SAMPLES:
 130       count = ctx->Driver.QuerySamplesForFormat(ctx, target,
 131             internalformat, buffer);
 132       break;
 133    case GL_NUM_SAMPLE_COUNTS: {
 134       if ((ctx->API == API_OPENGLES2 && ctx->Version == 30) &&
 135           _mesa_is_enum_format_integer(internalformat)) {
 136          /* From GL ES 3.0 specification, section 6.1.15 page 236: "Since
 137           * multisampling is not supported for signed and unsigned integer
 138           * internal formats, the value of NUM_SAMPLE_COUNTS will be zero
 139           * for such formats.
 140           *
 141           * Such a restriction no longer exists in GL ES 3.1.
 142           */
 143          buffer[0] = 0;
 144          count = 1;
 145       } else {
 146          size_t num_samples;
 147
 148          /* The driver can return 0, and we should pass that along to the
 149           * application.  The ARB decided that ARB_internalformat_query should
 150           * behave as ARB_internalformat_query2 in this situation.
 151           *
 152           * The ARB_internalformat_query2 spec says:
 153           *
 154           *     "- NUM_SAMPLE_COUNTS: The number of sample counts that would be
 155           *        returned by querying SAMPLES is returned in <params>.
 156           *        * If <internalformat> is not color-renderable,
 157           *          depth-renderable, or stencil-renderable (as defined in
 158           *          section 4.4.4), or if <target> does not support multiple
 159           *          samples (ie other than TEXTURE_2D_MULTISAMPLE,
 160           *          TEXTURE_2D_MULTISAMPLE_ARRAY, or RENDERBUFFER), 0 is
 161           *          returned."
 162           */
 163          num_samples =  ctx->Driver.QuerySamplesForFormat(ctx, target, internalformat, buffer);
 164
 165          /* QuerySamplesForFormat writes some stuff to buffer, so we have to
 166           * separately over-write it with the requested value.
 167           */
 168          buffer[0] = (GLint) num_samples;
 169          count = 1;
 170       }
 171       break;
 172    }
 173    default:
 174       _mesa_error(ctx, GL_INVALID_ENUM,
 175                   "glGetInternalformativ(pname=%s)",
 176                   _mesa_enum_to_string(pname));
 177       return;
 178    }
 179
 180    if (bufSize != 0 && params == NULL) {
 181       /* Emit a warning to aid application debugging, but go ahead and do the
 182        * memcpy (and probably crash) anyway.
 183        */
 184       _mesa_warning(ctx,
 185                     "glGetInternalformativ(bufSize = %d, but params = NULL)",
 186                     bufSize);
 187    }
 188
 189    /* Copy the data from the temporary buffer to the buffer supplied by the
 190     * application.  Clamp the size of the copy to the size supplied by the
 191     * application.
 192     */
 193    memcpy(params, buffer, MIN2(count, bufSize) * sizeof(GLint));
 194
 195    return;
 196 }