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) && ctx->Extensions.ARB_texture_multisample)
  78          break;
  79
  80    default:
  81       _mesa_error(ctx, GL_INVALID_ENUM,
  82                   "glGetInternalformativ(target=%s)",
  83                   _mesa_lookup_enum_by_nr(target));
  84       return;
  85    }
  86
  87    /* The ARB_internalformat_query spec says:
  88     *
  89     *     "If the <internalformat> parameter to GetInternalformativ is not
  90     *     color-, depth- or stencil-renderable, then an INVALID_ENUM error is
  91     *     generated."
  92     *
  93     * Page 243 of the GLES 3.0.4 spec says this for GetInternalformativ:
  94     *
  95     *     "internalformat must be color-renderable, depth-renderable or
  96     *     stencilrenderable (as defined in section 4.4.4)."
  97     *
  98     * Section 4.4.4 on page 212 of the same spec says:
  99     *
 100     *     "An internal format is color-renderable if it is one of the
 101     *     formats from table 3.13 noted as color-renderable or if it
 102     *     is unsized format RGBA or RGB."
 103     *
 104     * Therefore, we must accept GL_RGB and GL_RGBA here.
 105     */
 106    if (internalformat != GL_RGB && internalformat != GL_RGBA &&
 107        _mesa_base_fbo_format(ctx, internalformat) == 0) {
 108       _mesa_error(ctx, GL_INVALID_ENUM,
 109                   "glGetInternalformativ(internalformat=%s)",
 110                   _mesa_lookup_enum_by_nr(internalformat));
 111       return;
 112    }
 113
 114    /* The ARB_internalformat_query spec says:
 115     *
 116     *     "If the <bufSize> parameter to GetInternalformativ is negative, then
 117     *     an INVALID_VALUE error is generated."
 118     */
 119    if (bufSize < 0) {
 120       _mesa_error(ctx, GL_INVALID_VALUE,
 121                   "glGetInternalformativ(target=%s)",
 122                   _mesa_lookup_enum_by_nr(target));
 123       return;
 124    }
 125
 126    switch (pname) {
 127    case GL_SAMPLES:
 128       count = ctx->Driver.QuerySamplesForFormat(ctx, target,
 129             internalformat, buffer);
 130       break;
 131    case GL_NUM_SAMPLE_COUNTS: {
 132       if (_mesa_is_gles3(ctx) && _mesa_is_enum_format_integer(internalformat)) {
 133          /* From GL ES 3.0 specification, section 6.1.15 page 236: "Since
 134           * multisampling is not supported for signed and unsigned integer
 135           * internal formats, the value of NUM_SAMPLE_COUNTS will be zero
 136           * for such formats.
 137           */
 138          buffer[0] = 0;
 139          count = 1;
 140       } else {
 141          size_t num_samples;
 142
 143          /* The driver can return 0, and we should pass that along to the
 144           * application.  The ARB decided that ARB_internalformat_query should
 145           * behave as ARB_internalformat_query2 in this situation.
 146           *
 147           * The ARB_internalformat_query2 spec says:
 148           *
 149           *     "- NUM_SAMPLE_COUNTS: The number of sample counts that would be
 150           *        returned by querying SAMPLES is returned in <params>.
 151           *        * If <internalformat> is not color-renderable,
 152           *          depth-renderable, or stencil-renderable (as defined in
 153           *          section 4.4.4), or if <target> does not support multiple
 154           *          samples (ie other than TEXTURE_2D_MULTISAMPLE,
 155           *          TEXTURE_2D_MULTISAMPLE_ARRAY, or RENDERBUFFER), 0 is
 156           *          returned."
 157           */
 158          num_samples =  ctx->Driver.QuerySamplesForFormat(ctx, target, internalformat, buffer);
 159
 160          /* QuerySamplesForFormat writes some stuff to buffer, so we have to
 161           * separately over-write it with the requested value.
 162           */
 163          buffer[0] = (GLint) num_samples;
 164          count = 1;
 165       }
 166       break;
 167    }
 168    default:
 169       _mesa_error(ctx, GL_INVALID_ENUM,
 170                   "glGetInternalformativ(pname=%s)",
 171                   _mesa_lookup_enum_by_nr(pname));
 172       return;
 173    }
 174
 175    if (bufSize != 0 && params == NULL) {
 176       /* Emit a warning to aid application debugging, but go ahead and do the
 177        * memcpy (and probably crash) anyway.
 178        */
 179       _mesa_warning(ctx,
 180                     "glGetInternalformativ(bufSize = %d, but params = NULL)",
 181                     bufSize);
 182    }
 183
 184    /* Copy the data from the temporary buffer to the buffer supplied by the
 185     * application.  Clamp the size of the copy to the size supplied by the
 186     * application.
 187     */
 188    memcpy(params, buffer, MIN2(count, bufSize) * sizeof(GLint));
 189
 190    return;
 191 }