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_context.h"
31#include "st_atom.h"
32
33#include "cso_cache/cso_context.h"
34
35
36/* Second state atom for user clip planes:
37 */
38static void update_sample_mask( struct st_context *st )
39{
40   unsigned sample_mask = 0xffffffff;
41   unsigned sample_count = 1;
42   struct pipe_framebuffer_state *framebuffer = &st->state.framebuffer;
43
44   /* dependency here on bound surface (or rather, sample count) is worrying */
45   if (framebuffer->zsbuf)
46      sample_count = framebuffer->zsbuf->texture->nr_samples;
47   else if (framebuffer->cbufs[0])
48      sample_count = framebuffer->cbufs[0]->texture->nr_samples;
49
50   if (st->ctx->Multisample.Enabled && sample_count > 1) {
51   /* unlike in gallium/d3d10 the mask is only active if msaa is enabled */
52      if (st->ctx->Multisample.SampleCoverage) {
53         unsigned nr_bits;
54         nr_bits = st->ctx->Multisample.SampleCoverageValue * (float)sample_count;
55         /* there's lot of ways how to do this. We just use first few bits,
56            since we have no knowledge of sample positions here. When
57            app-supplied mask though is used too might need to be smarter.
58            Also, there's a interface restriction here in theory it is
59            encouraged this mask not be the same at each pixel. */
60         sample_mask = (1 << nr_bits) - 1;
61         if (st->ctx->Multisample.SampleCoverageInvert)
62            sample_mask = ~sample_mask;
63      }
64      /* TODO merge with app-supplied sample mask */
65   }
66
67   /* mask off unused bits or don't care? */
68
69   if (sample_mask != st->state.sample_mask) {
70      st->state.sample_mask = sample_mask;
71      cso_set_sample_mask(st->cso_context, sample_mask);
72   }
73}
74
75
76const struct st_tracked_state st_update_msaa = {
77   "st_update_msaa",					/* name */
78   {							/* dirty */
79      (_NEW_MULTISAMPLE | _NEW_BUFFERS),		/* mesa */
80      ST_NEW_FRAMEBUFFER,				/* st */
81   },
82   update_sample_mask					/* update */
83};
84