src/mesa/drivers/dri/i965/brw_formatquery.c

   1 /*
   2  * Copyright © 2015 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 DEALINGS
  21  * IN THE SOFTWARE.
  22  */
  23
  24 #include "brw_context.h"
  25 #include "brw_state.h"
  26 #include "main/context.h"
  27 #include "main/formatquery.h"
  28 #include "main/glformats.h"
  29
  30 static size_t
  31 brw_query_samples_for_format(struct gl_context *ctx, GLenum target,
  32                              GLenum internalFormat, int samples[16])
  33 {
  34    struct brw_context *brw = brw_context(ctx);
  35
  36    (void) target;
  37    (void) internalFormat;
  38
  39    switch (brw->gen) {
  40    case 10:
  41    case 9:
  42       samples[0] = 16;
  43       samples[1] = 8;
  44       samples[2] = 4;
  45       samples[3] = 2;
  46       return 4;
  47
  48    case 8:
  49       samples[0] = 8;
  50       samples[1] = 4;
  51       samples[2] = 2;
  52       return 3;
  53
  54    case 7:
  55       if (internalFormat == GL_RGBA32F && _mesa_is_gles(ctx)) {
  56          /* For GLES, we are allowed to return a smaller number of samples for
  57           * GL_RGBA32F. See OpenGLES 3.2 spec, section 20.3.1 Internal Format
  58           * Query Parameters, under SAMPLES:
  59           *
  60           * "A value less than or equal to the value of MAX_SAMPLES, if
  61           *  internalformat is RGBA16F, R32F, RG32F, or RGBA32F."
  62           *
  63           * In brw_render_target_supported, we prevent formats with a size
  64           * greater than 8 bytes from using 8x MSAA on gen7.
  65           */
  66          samples[0] = 4;
  67          return 1;
  68       } else {
  69          samples[0] = 8;
  70          samples[1] = 4;
  71          return 2;
  72       }
  73
  74    case 6:
  75       samples[0] = 4;
  76       return 1;
  77
  78    default:
  79       assert(brw->gen < 6);
  80       samples[0] = 1;
  81       return 1;
  82    }
  83 }
  84
  85 void
  86 brw_query_internal_format(struct gl_context *ctx, GLenum target,
  87                           GLenum internalFormat, GLenum pname, GLint *params)
  88 {
  89    /* The Mesa layer gives us a temporary params buffer that is guaranteed
  90     * to be non-NULL, and have at least 16 elements.
  91     */
  92    assert(params != NULL);
  93
  94    switch (pname) {
  95    case GL_SAMPLES:
  96       brw_query_samples_for_format(ctx, target, internalFormat, params);
  97       break;
  98
  99    case GL_NUM_SAMPLE_COUNTS: {
 100       size_t num_samples;
 101       GLint dummy_buffer[16];
 102
 103       num_samples = brw_query_samples_for_format(ctx, target, internalFormat,
 104                                                  dummy_buffer);
 105       params[0] = (GLint) num_samples;
 106       break;
 107    }
 108
 109    default:
 110       /* By default, we call the driver hook's fallback function from the frontend,
 111        * which has generic implementation for all pnames.
 112        */
 113       _mesa_query_internal_format_default(ctx, target, internalFormat, pname,
 114                                           params);
 115       break;
 116    }
 117 }