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    const struct gen_device_info *devinfo = &brw->screen->devinfo;
  36
  37    (void) target;
  38    (void) internalFormat;
  39
  40    switch (devinfo->gen) {
  41    case 10:
  42    case 9:
  43       samples[0] = 16;
  44       samples[1] = 8;
  45       samples[2] = 4;
  46       samples[3] = 2;
  47       return 4;
  48
  49    case 8:
  50       samples[0] = 8;
  51       samples[1] = 4;
  52       samples[2] = 2;
  53       return 3;
  54
  55    case 7:
  56       if (internalFormat == GL_RGBA32F && _mesa_is_gles(ctx)) {
  57          /* For GLES, we are allowed to return a smaller number of samples for
  58           * GL_RGBA32F. See OpenGLES 3.2 spec, section 20.3.1 Internal Format
  59           * Query Parameters, under SAMPLES:
  60           *
  61           * "A value less than or equal to the value of MAX_SAMPLES, if
  62           *  internalformat is RGBA16F, R32F, RG32F, or RGBA32F."
  63           *
  64           * In brw_render_target_supported, we prevent formats with a size
  65           * greater than 8 bytes from using 8x MSAA on gen7.
  66           */
  67          samples[0] = 4;
  68          return 1;
  69       } else {
  70          samples[0] = 8;
  71          samples[1] = 4;
  72          return 2;
  73       }
  74
  75    case 6:
  76       samples[0] = 4;
  77       return 1;
  78
  79    default:
  80       assert(devinfo->gen < 6);
  81       samples[0] = 1;
  82       return 1;
  83    }
  84 }
  85
  86 void
  87 brw_query_internal_format(struct gl_context *ctx, GLenum target,
  88                           GLenum internalFormat, GLenum pname, GLint *params)
  89 {
  90    /* The Mesa layer gives us a temporary params buffer that is guaranteed
  91     * to be non-NULL, and have at least 16 elements.
  92     */
  93    assert(params != NULL);
  94
  95    switch (pname) {
  96    case GL_SAMPLES:
  97       brw_query_samples_for_format(ctx, target, internalFormat, params);
  98       break;
  99
 100    case GL_NUM_SAMPLE_COUNTS: {
 101       size_t num_samples;
 102       GLint dummy_buffer[16];
 103
 104       num_samples = brw_query_samples_for_format(ctx, target, internalFormat,
 105                                                  dummy_buffer);
 106       params[0] = (GLint) num_samples;
 107       break;
 108    }
 109
 110    default:
 111       /* By default, we call the driver hook's fallback function from the frontend,
 112        * which has generic implementation for all pnames.
 113        */
 114       _mesa_query_internal_format_default(ctx, target, internalFormat, pname,
 115                                           params);
 116       break;
 117    }
 118 }