1/*
2 * Copyright © 2020 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 "intel_sample_positions.h"
25
26/**
27 * 1x MSAA has a single sample at the center: (0.5, 0.5) -> (0x8, 0x8).
28 */
29const struct intel_sample_position intel_sample_positions_1x[] = {
30   { 0.5, 0.5, },
31};
32
33/**
34 * 2x MSAA sample positions are (0.25, 0.25) and (0.75, 0.75):
35 *   4 c
36 * 4 0
37 * c   1
38 */
39const struct intel_sample_position intel_sample_positions_2x[] = {
40   { 0.75, 0.75 },
41   { 0.25, 0.25 },
42};
43
44/**
45 * Sample positions:
46 *   2 6 a e
47 * 2   0
48 * 6       1
49 * a 2
50 * e     3
51 */
52const struct intel_sample_position intel_sample_positions_4x[] = {
53   { 0.375, 0.125 },
54   { 0.875, 0.375 },
55   { 0.125, 0.625 },
56   { 0.625, 0.875 },
57};
58
59/**
60 * Sample positions:
61 *
62 * From the Ivy Bridge PRM, Vol2 Part1 p304 (3DSTATE_MULTISAMPLE:
63 * Programming Notes):
64 *     "When programming the sample offsets (for NUMSAMPLES_4 or _8 and
65 *     MSRASTMODE_xxx_PATTERN), the order of the samples 0 to 3 (or 7
66 *     for 8X) must have monotonically increasing distance from the
67 *     pixel center. This is required to get the correct centroid
68 *     computation in the device."
69 *
70 * Sample positions:
71 *   1 3 5 7 9 b d f
72 * 1               7
73 * 3     3
74 * 5         0
75 * 7 5
76 * 9             2
77 * b       1
78 * d   4
79 * f           6
80 */
81const struct intel_sample_position intel_sample_positions_8x[] = {
82   { 0.5625, 0.3125 },
83   { 0.4375, 0.6875 },
84   { 0.8125, 0.5625 },
85   { 0.3125, 0.1875 },
86   { 0.1875, 0.8125 },
87   { 0.0625, 0.4375 },
88   { 0.6875, 0.9375 },
89   { 0.9375, 0.0625 },
90};
91
92/**
93 * Sample positions:
94 *
95 *    0 1 2 3 4 5 6 7 8 9 a b c d e f
96 * 0   15
97 * 1                  9
98 * 2         10
99 * 3                        7
100 * 4                               13
101 * 5                1
102 * 6        4
103 * 7                          3
104 * 8 12
105 * 9                    0
106 * a            2
107 * b                            6
108 * c     11
109 * d                      5
110 * e              8
111 * f                             14
112 */
113const struct intel_sample_position intel_sample_positions_16x[] = {
114   { 0.5625, 0.5625 },
115   { 0.4375, 0.3125 },
116   { 0.3125, 0.6250 },
117   { 0.7500, 0.4375 },
118   { 0.1875, 0.3750 },
119   { 0.6250, 0.8125 },
120   { 0.8125, 0.6875 },
121   { 0.6875, 0.1875 },
122   { 0.3750, 0.8750 },
123   { 0.5000, 0.0625 },
124   { 0.2500, 0.1250 },
125   { 0.1250, 0.7500 },
126   { 0.0000, 0.5000 },
127   { 0.9375, 0.2500 },
128   { 0.8750, 0.9375 },
129   { 0.0625, 0.0000 },
130};
131