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 11:
  42    case 10:
  43    case 9:
  44       samples[0] = 16;
  45       samples[1] = 8;
  46       samples[2] = 4;
  47       samples[3] = 2;
  48       return 4;
  49
  50    case 8:
  51       samples[0] = 8;
  52       samples[1] = 4;
  53       samples[2] = 2;
  54       return 3;
  55
  56    case 7:
  57       if (internalFormat == GL_RGBA32F && _mesa_is_gles(ctx)) {
  58          /* For GLES, we are allowed to return a smaller number of samples for
  59           * GL_RGBA32F. See OpenGLES 3.2 spec, section 20.3.1 Internal Format
  60           * Query Parameters, under SAMPLES:
  61           *
  62           * "A value less than or equal to the value of MAX_SAMPLES, if
  63           *  internalformat is RGBA16F, R32F, RG32F, or RGBA32F."
  64           *
  65           * In brw_render_target_supported, we prevent formats with a size
  66           * greater than 8 bytes from using 8x MSAA on gen7.
  67           */
  68          samples[0] = 4;
  69          return 1;
  70       } else {
  71          samples[0] = 8;
  72          samples[1] = 4;
  73          return 2;
  74       }
  75
  76    case 6:
  77       samples[0] = 4;
  78       return 1;
  79
  80    default:
  81       assert(devinfo->gen < 6);
  82       samples[0] = 1;
  83       return 1;
  84    }
  85 }
  86
  87 void
  88 brw_query_internal_format(struct gl_context *ctx, GLenum target,
  89                           GLenum internalFormat, GLenum pname, GLint *params)
  90 {
  91    /* The Mesa layer gives us a temporary params buffer that is guaranteed
  92     * to be non-NULL, and have at least 16 elements.
  93     */
  94    assert(params != NULL);
  95
  96    switch (pname) {
  97    case GL_SAMPLES:
  98       brw_query_samples_for_format(ctx, target, internalFormat, params);
  99       break;
 100
 101    case GL_NUM_SAMPLE_COUNTS: {
 102       size_t num_samples;
 103       GLint dummy_buffer[16];
 104
 105       num_samples = brw_query_samples_for_format(ctx, target, internalFormat,
 106                                                  dummy_buffer);
 107       params[0] = (GLint) num_samples;
 108       break;
 109    }
 110
 111    default:
 112       /* By default, we call the driver hook's fallback function from the frontend,
 113        * which has generic implementation for all pnames.
 114        */
 115       _mesa_query_internal_format_default(ctx, target, internalFormat, pname,
 116                                           params);
 117       break;
 118    }
 119 }