SkPM4fPriv.h revision fbc1e296b2e98dc76de533a2bb45d9ccc8c2498f 
1/*
2 * Copyright 2016 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "SkColorPriv.h"
9#include "SkNx.h"
10
11static inline float get_alpha(const Sk4f& f4) {
12    return f4.kth<SkPM4f::A>();
13}
14
15static inline Sk4f set_alpha(const Sk4f& f4, float alpha) {
16    static_assert(3 == SkPM4f::A, "");
17    return Sk4f(f4.kth<0>(), f4.kth<1>(), f4.kth<2>(), alpha);
18}
19
20static inline uint32_t to_4b(const Sk4f& f4) {
21    uint32_t b4;
22    SkNx_cast<uint8_t>(f4).store((uint8_t*)&b4);
23    return b4;
24}
25
26static inline Sk4f to_4f(uint32_t b4) {
27    return SkNx_cast<float>(Sk4b::Load((const uint8_t*)&b4));
28}
29
30static inline Sk4f s2l(const Sk4f& s4) {
31    return set_alpha(s4 * s4, get_alpha(s4));
32}
33
34static inline Sk4f l2s(const Sk4f& l4) {
35    return set_alpha(l4.rsqrt1() * l4, get_alpha(l4));
36}
37
38///////////////////////////////////////////////////////////////////////////////////////////////////
39
40static inline Sk4f Sk4f_fromL32(uint32_t src) {
41    return to_4f(src) * Sk4f(1.0f/255);
42}
43
44static inline Sk4f Sk4f_fromS32(uint32_t src) {
45    return s2l(to_4f(src) * Sk4f(1.0f/255));
46}
47
48static inline uint32_t Sk4f_toL32(const Sk4f& x4) {
49    return to_4b(x4 * Sk4f(255) + Sk4f(0.5f));
50}
51
52static inline uint32_t Sk4f_toS32(const Sk4f& x4) {
53    return to_4b(l2s(x4) * Sk4f(255) + Sk4f(0.5f));
54}
55
56///////////////////////////////////////////////////////////////////////////////////////////////////
57
58static Sk4f unit_to_l255_round(const SkPM4f& pm4) {
59    return Sk4f::Load(pm4.fVec) * Sk4f(255) + Sk4f(0.5f);
60}
61
62static Sk4f unit_to_s255_round(const SkPM4f& pm4) {
63    return l2s(Sk4f::Load(pm4.fVec)) * Sk4f(255) + Sk4f(0.5f);
64}
65
66static inline void SkPM4f_l32_src_mode(SkPMColor dst[], const SkPM4f src[], int count) {
67    for (int i = 0; i < (count >> 2); ++i) {
68        SkASSERT(src[0].isUnit());
69        SkASSERT(src[1].isUnit());
70        SkASSERT(src[2].isUnit());
71        SkASSERT(src[3].isUnit());
72        Sk4f_ToBytes((uint8_t*)dst,
73                     unit_to_l255_round(src[0]), unit_to_l255_round(src[1]),
74                     unit_to_l255_round(src[2]), unit_to_l255_round(src[3]));
75        src += 4;
76        dst += 4;
77    }
78    count &= 3;
79    for (int i = 0; i < count; ++i) {
80        SkASSERT(src[i].isUnit());
81        SkNx_cast<uint8_t>(unit_to_l255_round(src[i])).store((uint8_t*)&dst[i]);
82    }
83}
84
85static inline void SkPM4f_l32_srcover_mode(SkPMColor dst[], const SkPM4f src[], int count) {
86    for (int i = 0; i < count; ++i) {
87        SkASSERT(src[i].isUnit());
88        Sk4f s4 = Sk4f::Load(src[i].fVec);
89        Sk4f d4 = Sk4f_fromL32(dst[i]);
90        dst[i] = Sk4f_toL32(s4 + d4 * Sk4f(1 - get_alpha(s4)));
91    }
92}
93
94static inline void SkPM4f_s32_src_mode(SkPMColor dst[], const SkPM4f src[], int count) {
95    for (int i = 0; i < (count >> 2); ++i) {
96        SkASSERT(src[0].isUnit());
97        SkASSERT(src[1].isUnit());
98        SkASSERT(src[2].isUnit());
99        SkASSERT(src[3].isUnit());
100        Sk4f_ToBytes((uint8_t*)dst,
101                     unit_to_s255_round(src[0]), unit_to_s255_round(src[1]),
102                     unit_to_s255_round(src[2]), unit_to_s255_round(src[3]));
103        src += 4;
104        dst += 4;
105    }
106    count &= 3;
107    for (int i = 0; i < count; ++i) {
108        SkASSERT(src[i].isUnit());
109        SkNx_cast<uint8_t>(unit_to_s255_round(src[i])).store((uint8_t*)&dst[i]);
110    }
111}
112
113static inline void SkPM4f_s32_srcover_mode(SkPMColor dst[], const SkPM4f src[], int count) {
114    for (int i = 0; i < count; ++i) {
115        SkASSERT(src[i].isUnit());
116        Sk4f s4 = Sk4f::Load(src[i].fVec);
117        Sk4f d4 = Sk4f_fromS32(dst[i]);
118        dst[i] = Sk4f_toS32(s4 + d4 * Sk4f(1 - get_alpha(s4)));
119    }
120}
121
122