src/mesa/state_tracker/st_atom_msaa.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2010 VMware, Inc.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL THE AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28
  29 #include "st_context.h"
  30 #include "pipe/p_screen.h"
  31 #include "pipe/p_context.h"
  32 #include "st_atom.h"
  33 #include "st_program.h"
  34 #include "st_util.h"
  35
  36 #include "cso_cache/cso_context.h"
  37 #include "util/u_framebuffer.h"
  38 #include "main/framebuffer.h"
  39
  40
  41 /**
  42  * Update the sample locations
  43  */
  44 static void
  45 update_sample_locations(struct st_context *st)
  46 {
  47    struct gl_framebuffer *fb = st->ctx->DrawBuffer;
  48
  49    if (!st->ctx->Extensions.ARB_sample_locations)
  50       return;
  51
  52    if (fb->ProgrammableSampleLocations) {
  53       unsigned grid_width, grid_height, size, pixel, sample_index;
  54       unsigned samples = st->state.fb_num_samples;
  55       bool sample_location_pixel_grid = fb->SampleLocationPixelGrid;
  56       uint8_t locations[
  57          PIPE_MAX_SAMPLE_LOCATION_GRID_SIZE *
  58          PIPE_MAX_SAMPLE_LOCATION_GRID_SIZE * 32];
  59
  60       st->pipe->screen->get_sample_pixel_grid(
  61          st->pipe->screen, samples, &grid_width, &grid_height);
  62       size = grid_width * grid_height * samples;
  63
  64       /**
  65        * when a dimension is greater than MAX_SAMPLE_LOCATION_GRID_SIZE,
  66        * st->ctx->Driver.GetSamplePixelGrid() returns 1 for both dimensions.
  67        */
  68       if (grid_width > MAX_SAMPLE_LOCATION_GRID_SIZE ||
  69           grid_height > MAX_SAMPLE_LOCATION_GRID_SIZE)
  70          sample_location_pixel_grid = false;
  71
  72       for (pixel = 0; pixel < grid_width * grid_height; pixel++) {
  73          for (sample_index = 0; sample_index < samples; sample_index++) {
  74             int table_index = sample_index;
  75             float x = 0.5f, y = 0.5f;
  76             uint8_t loc;
  77             if (sample_location_pixel_grid)
  78                table_index = pixel * samples + sample_index;
  79             if (fb->SampleLocationTable) {
  80                x = fb->SampleLocationTable[table_index*2];
  81                y = fb->SampleLocationTable[table_index*2+1];
  82             }
  83             if (st->state.fb_orientation == Y_0_BOTTOM)
  84                y = 1.0 - y;
  85
  86             loc = roundf(CLAMP(x * 16.0f, 0.0f, 15.0f));
  87             loc |= (int)roundf(CLAMP(y * 16.0f, 0.0f, 15.0f)) << 4;
  88             locations[pixel * samples + sample_index] = loc;
  89          }
  90       }
  91
  92       util_sample_locations_flip_y(
  93          st->pipe->screen, st->state.fb_height, samples, locations);
  94
  95       if (!st->state.enable_sample_locations ||
  96           st->state.sample_locations_samples != samples ||
  97           memcmp(locations, st->state.sample_locations, size) != 0) {
  98          st->pipe->set_sample_locations( st->pipe, size, locations);
  99
 100          st->state.sample_locations_samples = samples;
 101          memcpy(st->state.sample_locations, locations, size);
 102       }
 103    } else if (st->state.enable_sample_locations) {
 104       st->pipe->set_sample_locations(st->pipe, 0, NULL);
 105    }
 106
 107    st->state.enable_sample_locations = fb->ProgrammableSampleLocations;
 108 }
 109
 110
 111 /* Update the sample mask and locations for MSAA.
 112  */
 113 void
 114 st_update_sample_state(struct st_context *st)
 115 {
 116    unsigned sample_mask = 0xffffffff;
 117    unsigned sample_count = st->state.fb_num_samples;
 118
 119    if (_mesa_is_multisample_enabled(st->ctx) && sample_count > 1) {
 120       /* unlike in gallium/d3d10 the mask is only active if msaa is enabled */
 121       if (st->ctx->Multisample.SampleCoverage) {
 122          unsigned nr_bits = (unsigned)
 123             (st->ctx->Multisample.SampleCoverageValue * (float) sample_count);
 124          /* there's lot of ways how to do this. We just use first few bits,
 125           * since we have no knowledge of sample positions here. When
 126           * app-supplied mask though is used too might need to be smarter.
 127           * Also, there's an interface restriction here in theory it is
 128           * encouraged this mask not be the same at each pixel.
 129           */
 130          sample_mask = (1 << nr_bits) - 1;
 131          if (st->ctx->Multisample.SampleCoverageInvert)
 132             sample_mask = ~sample_mask;
 133       }
 134       if (st->ctx->Multisample.SampleMask)
 135          sample_mask &= st->ctx->Multisample.SampleMaskValue;
 136    }
 137
 138    cso_set_sample_mask(st->cso_context, sample_mask);
 139
 140    update_sample_locations(st);
 141 }
 142
 143
 144 void
 145 st_update_sample_shading(struct st_context *st)
 146 {
 147    if (!st->fp)
 148       return;
 149
 150    if (!st->ctx->Extensions.ARB_sample_shading)
 151       return;
 152
 153    cso_set_min_samples(st->cso_context,
 154          _mesa_get_min_invocations_per_fragment(st->ctx, &st->fp->Base));
 155 }