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
  35 #include "cso_cache/cso_context.h"
  36 #include "util/u_framebuffer.h"
  37 #include "main/framebuffer.h"
  38
  39
  40 /**
  41  * Update the sample locations
  42  */
  43 static void
  44 update_sample_locations(struct st_context *st)
  45 {
  46    struct gl_framebuffer *fb = st->ctx->DrawBuffer;
  47
  48    if (!st->ctx->Extensions.ARB_sample_locations)
  49       return;
  50
  51    if (fb->ProgrammableSampleLocations) {
  52       unsigned grid_width, grid_height, size, pixel, sample_index;
  53       unsigned samples = st->state.fb_num_samples;
  54       bool sample_location_pixel_grid = fb->SampleLocationPixelGrid;
  55       uint8_t locations[
  56          PIPE_MAX_SAMPLE_LOCATION_GRID_SIZE *
  57          PIPE_MAX_SAMPLE_LOCATION_GRID_SIZE * 32];
  58
  59       st->pipe->screen->get_sample_pixel_grid(
  60          st->pipe->screen, samples, &grid_width, &grid_height);
  61       size = grid_width * grid_height * samples;
  62
  63       /**
  64        * when a dimension is greater than MAX_SAMPLE_LOCATION_GRID_SIZE,
  65        * st->ctx->Driver.GetSamplePixelGrid() returns 1 for both dimensions.
  66        */
  67       if (grid_width > MAX_SAMPLE_LOCATION_GRID_SIZE ||
  68           grid_height > MAX_SAMPLE_LOCATION_GRID_SIZE)
  69          sample_location_pixel_grid = false;
  70
  71       for (pixel = 0; pixel < grid_width * grid_height; pixel++) {
  72          for (sample_index = 0; sample_index < samples; sample_index++) {
  73             int table_index = sample_index;
  74             float x = 0.5f, y = 0.5f;
  75             uint8_t loc;
  76             if (sample_location_pixel_grid)
  77                table_index = pixel * samples + sample_index;
  78             if (fb->SampleLocationTable) {
  79                x = fb->SampleLocationTable[table_index*2];
  80                y = fb->SampleLocationTable[table_index*2+1];
  81             }
  82             if (st->state.fb_orientation == Y_0_BOTTOM)
  83                y = 1.0 - y;
  84
  85             loc = roundf(CLAMP(x * 16.0f, 0.0f, 15.0f));
  86             loc |= (int)roundf(CLAMP(y * 16.0f, 0.0f, 15.0f)) << 4;
  87             locations[pixel * samples + sample_index] = loc;
  88          }
  89       }
  90
  91       util_sample_locations_flip_y(
  92          st->pipe->screen, st->state.fb_height, samples, locations);
  93
  94       if (!st->state.enable_sample_locations ||
  95           st->state.sample_locations_samples != samples ||
  96           memcmp(locations, st->state.sample_locations, size) != 0) {
  97          st->pipe->set_sample_locations( st->pipe, size, locations);
  98
  99          st->state.sample_locations_samples = samples;
 100          memcpy(st->state.sample_locations, locations, size);
 101       }
 102    } else if (st->state.enable_sample_locations) {
 103       st->pipe->set_sample_locations(st->pipe, 0, NULL);
 104    }
 105
 106    st->state.enable_sample_locations = fb->ProgrammableSampleLocations;
 107 }
 108
 109
 110 /* Update the sample mask and locations for MSAA.
 111  */
 112 void
 113 st_update_sample_state(struct st_context *st)
 114 {
 115    unsigned sample_mask = 0xffffffff;
 116    unsigned sample_count = st->state.fb_num_samples;
 117
 118    if (_mesa_is_multisample_enabled(st->ctx) && sample_count > 1) {
 119       /* unlike in gallium/d3d10 the mask is only active if msaa is enabled */
 120       if (st->ctx->Multisample.SampleCoverage) {
 121          unsigned nr_bits = (unsigned)
 122             (st->ctx->Multisample.SampleCoverageValue * (float) sample_count);
 123          /* there's lot of ways how to do this. We just use first few bits,
 124           * since we have no knowledge of sample positions here. When
 125           * app-supplied mask though is used too might need to be smarter.
 126           * Also, there's an interface restriction here in theory it is
 127           * encouraged this mask not be the same at each pixel.
 128           */
 129          sample_mask = (1 << nr_bits) - 1;
 130          if (st->ctx->Multisample.SampleCoverageInvert)
 131             sample_mask = ~sample_mask;
 132       }
 133       if (st->ctx->Multisample.SampleMask)
 134          sample_mask &= st->ctx->Multisample.SampleMaskValue;
 135    }
 136
 137    cso_set_sample_mask(st->cso_context, sample_mask);
 138
 139    update_sample_locations(st);
 140 }
 141
 142
 143 void
 144 st_update_sample_shading(struct st_context *st)
 145 {
 146    if (!st->fp)
 147       return;
 148
 149    if (!st->ctx->Extensions.ARB_sample_shading)
 150       return;
 151
 152    cso_set_min_samples(st->cso_context,
 153          _mesa_get_min_invocations_per_fragment(st->ctx, &st->fp->Base));
 154 }