1 /*
2 * Copyright 2006 The Android Open Source Project
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 "SkColor.h"
9 #include "SkColorPriv.h"
10 #include "SkFixed.h"
11
SkPreMultiplyARGB(U8CPU a,U8CPU r,U8CPU g,U8CPU b)12 SkPMColor SkPreMultiplyARGB(U8CPU a, U8CPU r, U8CPU g, U8CPU b) {
13 return SkPremultiplyARGBInline(a, r, g, b);
14 }
15
SkPreMultiplyColor(SkColor c)16 SkPMColor SkPreMultiplyColor(SkColor c) {
17 return SkPremultiplyARGBInline(SkColorGetA(c), SkColorGetR(c),
18 SkColorGetG(c), SkColorGetB(c));
19 }
20
21 ///////////////////////////////////////////////////////////////////////////////
22
ByteToScalar(U8CPU x)23 static inline SkScalar ByteToScalar(U8CPU x) {
24 SkASSERT(x <= 255);
25 return SkIntToScalar(x) / 255;
26 }
27
ByteDivToScalar(int numer,U8CPU denom)28 static inline SkScalar ByteDivToScalar(int numer, U8CPU denom) {
29 // cast to keep the answer signed
30 return SkIntToScalar(numer) / (int)denom;
31 }
32
SkRGBToHSV(U8CPU r,U8CPU g,U8CPU b,SkScalar hsv[3])33 void SkRGBToHSV(U8CPU r, U8CPU g, U8CPU b, SkScalar hsv[3]) {
34 SkASSERT(hsv);
35
36 unsigned min = SkMin32(r, SkMin32(g, b));
37 unsigned max = SkMax32(r, SkMax32(g, b));
38 unsigned delta = max - min;
39
40 SkScalar v = ByteToScalar(max);
41 SkASSERT(v >= 0 && v <= SK_Scalar1);
42
43 if (0 == delta) { // we're a shade of gray
44 hsv[0] = 0;
45 hsv[1] = 0;
46 hsv[2] = v;
47 return;
48 }
49
50 SkScalar s = ByteDivToScalar(delta, max);
51 SkASSERT(s >= 0 && s <= SK_Scalar1);
52
53 SkScalar h;
54 if (r == max) {
55 h = ByteDivToScalar(g - b, delta);
56 } else if (g == max) {
57 h = SkIntToScalar(2) + ByteDivToScalar(b - r, delta);
58 } else { // b == max
59 h = SkIntToScalar(4) + ByteDivToScalar(r - g, delta);
60 }
61
62 h *= 60;
63 if (h < 0) {
64 h += SkIntToScalar(360);
65 }
66 SkASSERT(h >= 0 && h < SkIntToScalar(360));
67
68 hsv[0] = h;
69 hsv[1] = s;
70 hsv[2] = v;
71 }
72
SkHSVToColor(U8CPU a,const SkScalar hsv[3])73 SkColor SkHSVToColor(U8CPU a, const SkScalar hsv[3]) {
74 SkASSERT(hsv);
75
76 U8CPU s = SkUnitScalarClampToByte(hsv[1]);
77 U8CPU v = SkUnitScalarClampToByte(hsv[2]);
78
79 if (0 == s) { // shade of gray
80 return SkColorSetARGB(a, v, v, v);
81 }
82 SkFixed hx = (hsv[0] < 0 || hsv[0] >= SkIntToScalar(360)) ? 0 : SkScalarToFixed(hsv[0]/60);
83 SkFixed f = hx & 0xFFFF;
84
85 unsigned v_scale = SkAlpha255To256(v);
86 unsigned p = SkAlphaMul(255 - s, v_scale);
87 unsigned q = SkAlphaMul(255 - (s * f >> 16), v_scale);
88 unsigned t = SkAlphaMul(255 - (s * (SK_Fixed1 - f) >> 16), v_scale);
89
90 unsigned r, g, b;
91
92 SkASSERT((unsigned)(hx >> 16) < 6);
93 switch (hx >> 16) {
94 case 0: r = v; g = t; b = p; break;
95 case 1: r = q; g = v; b = p; break;
96 case 2: r = p; g = v; b = t; break;
97 case 3: r = p; g = q; b = v; break;
98 case 4: r = t; g = p; b = v; break;
99 default: r = v; g = p; b = q; break;
100 }
101 return SkColorSetARGB(a, r, g, b);
102 }
103
104 ///////////////////////////////////////////////////////////////////////////////////////////////////
105 #include "SkPM4fPriv.h"
106 #include "SkHalf.h"
107
FromPMColor(SkPMColor c)108 SkPM4f SkPM4f::FromPMColor(SkPMColor c) {
109 return From4f(swizzle_rb_if_bgra(Sk4f_fromL32(c)));
110 }
111
unpremul() const112 SkColor4f SkPM4f::unpremul() const {
113 float alpha = fVec[A];
114 if (0 == alpha) {
115 return { 0, 0, 0, 0 };
116 } else {
117 float invAlpha = 1 / alpha;
118 return { fVec[R] * invAlpha, fVec[G] * invAlpha, fVec[B] * invAlpha, alpha };
119 }
120 }
121
toF16(uint16_t half[4]) const122 void SkPM4f::toF16(uint16_t half[4]) const {
123 for (int i = 0; i < 4; ++i) {
124 half[i] = SkFloatToHalf(fVec[i]);
125 }
126 }
127
toF16() const128 uint64_t SkPM4f::toF16() const {
129 uint64_t value;
130 this->toF16(reinterpret_cast<uint16_t*>(&value));
131 return value;
132 }
133
FromF16(const uint16_t half[4])134 SkPM4f SkPM4f::FromF16(const uint16_t half[4]) {
135 return {{
136 SkHalfToFloat(half[0]),
137 SkHalfToFloat(half[1]),
138 SkHalfToFloat(half[2]),
139 SkHalfToFloat(half[3])
140 }};
141 }
142
143 #ifdef SK_DEBUG
assertIsUnit() const144 void SkPM4f::assertIsUnit() const {
145 auto c4 = Sk4f::Load(fVec);
146 SkASSERT((c4 >= Sk4f(0)).allTrue() && (c4 <= Sk4f(1)).allTrue());
147 }
148 #endif
149
150 ///////////////////////////////////////////////////////////////////////////////////////////////////
151
FromColor(SkColor bgra)152 SkColor4f SkColor4f::FromColor(SkColor bgra) {
153 SkColor4f rgba;
154 swizzle_rb(Sk4f_fromS32(bgra)).store(rgba.vec());
155 return rgba;
156 }
157
FromColor3f(SkColor3f color3f,float a)158 SkColor4f SkColor4f::FromColor3f(SkColor3f color3f, float a) {
159 SkColor4f rgba;
160 rgba.fR = color3f.fX;
161 rgba.fG = color3f.fY;
162 rgba.fB = color3f.fZ;
163 rgba.fA = a;
164 return rgba;
165 }
166
toSkColor() const167 SkColor SkColor4f::toSkColor() const {
168 return Sk4f_toS32(swizzle_rb(Sk4f::Load(this->vec())));
169 }
170
Pin(float r,float g,float b,float a)171 SkColor4f SkColor4f::Pin(float r, float g, float b, float a) {
172 SkColor4f c4;
173 Sk4f::Min(Sk4f::Max(Sk4f(r, g, b, a), Sk4f(0)), Sk4f(1)).store(c4.vec());
174 return c4;
175 }
176
premul() const177 SkPM4f SkColor4f::premul() const {
178 auto src = Sk4f::Load(this->pin().vec());
179 float srcAlpha = src[3]; // need the pinned version of our alpha
180 src = src * Sk4f(srcAlpha, srcAlpha, srcAlpha, 1);
181
182 return SkPM4f::From4f(src);
183 }
184