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 "SkEmbossMaskFilter.h"
9 #include "SkBlurMaskFilter.h"
10 #include "SkBlurMask.h"
11 #include "SkEmbossMask.h"
12 #include "SkReadBuffer.h"
13 #include "SkWriteBuffer.h"
14 #include "SkString.h"
15
Make(SkScalar blurSigma,const Light & light)16 sk_sp<SkMaskFilter> SkEmbossMaskFilter::Make(SkScalar blurSigma, const Light& light) {
17 return sk_sp<SkMaskFilter>(new SkEmbossMaskFilter(blurSigma, light));
18 }
19
20 #ifdef SK_SUPPORT_LEGACY_EMBOSSMASKFILTER
MakeEmboss(SkScalar blurSigma,const SkScalar direction[3],SkScalar ambient,SkScalar specular)21 sk_sp<SkMaskFilter> SkBlurMaskFilter::MakeEmboss(SkScalar blurSigma, const SkScalar direction[3],
22 SkScalar ambient, SkScalar specular) {
23 if (direction == nullptr) {
24 return nullptr;
25 }
26
27 SkEmbossMaskFilter::Light light;
28
29 memcpy(light.fDirection, direction, sizeof(light.fDirection));
30 // ambient should be 0...1 as a scalar
31 light.fAmbient = SkUnitScalarClampToByte(ambient);
32 // specular should be 0..15.99 as a scalar
33 static const SkScalar kSpecularMultiplier = SkIntToScalar(255) / 16;
34 light.fSpecular = static_cast<U8CPU>(SkScalarPin(specular, 0, 16) * kSpecularMultiplier + 0.5);
35
36 return SkEmbossMaskFilter::Make(blurSigma, light);
37 }
38 #endif
39
40 ///////////////////////////////////////////////////////////////////////////////
41
normalize(SkScalar v[3])42 static void normalize(SkScalar v[3]) {
43 SkScalar mag = SkScalarSquare(v[0]) + SkScalarSquare(v[1]) + SkScalarSquare(v[2]);
44 mag = SkScalarSqrt(mag);
45
46 for (int i = 0; i < 3; i++) {
47 v[i] /= mag;
48 }
49 }
50
SkEmbossMaskFilter(SkScalar blurSigma,const Light & light)51 SkEmbossMaskFilter::SkEmbossMaskFilter(SkScalar blurSigma, const Light& light)
52 : fLight(light), fBlurSigma(blurSigma) {
53 normalize(fLight.fDirection);
54 }
55
getFormat() const56 SkMask::Format SkEmbossMaskFilter::getFormat() const {
57 return SkMask::k3D_Format;
58 }
59
filterMask(SkMask * dst,const SkMask & src,const SkMatrix & matrix,SkIPoint * margin) const60 bool SkEmbossMaskFilter::filterMask(SkMask* dst, const SkMask& src,
61 const SkMatrix& matrix, SkIPoint* margin) const {
62 SkScalar sigma = matrix.mapRadius(fBlurSigma);
63
64 if (!SkBlurMask::BoxBlur(dst, src, sigma, kInner_SkBlurStyle, kLow_SkBlurQuality)) {
65 return false;
66 }
67
68 dst->fFormat = SkMask::k3D_Format;
69 if (margin) {
70 margin->set(SkScalarCeilToInt(3*sigma), SkScalarCeilToInt(3*sigma));
71 }
72
73 if (src.fImage == nullptr) {
74 return true;
75 }
76
77 // create a larger buffer for the other two channels (should force fBlur to do this for us)
78
79 {
80 uint8_t* alphaPlane = dst->fImage;
81 size_t planeSize = dst->computeImageSize();
82 if (0 == planeSize) {
83 return false; // too big to allocate, abort
84 }
85 dst->fImage = SkMask::AllocImage(planeSize * 3);
86 memcpy(dst->fImage, alphaPlane, planeSize);
87 SkMask::FreeImage(alphaPlane);
88 }
89
90 // run the light direction through the matrix...
91 Light light = fLight;
92 matrix.mapVectors((SkVector*)(void*)light.fDirection,
93 (SkVector*)(void*)fLight.fDirection, 1);
94
95 // now restore the length of the XY component
96 // cast to SkVector so we can call setLength (this double cast silences alias warnings)
97 SkVector* vec = (SkVector*)(void*)light.fDirection;
98 vec->setLength(light.fDirection[0],
99 light.fDirection[1],
100 SkPoint::Length(fLight.fDirection[0], fLight.fDirection[1]));
101
102 SkEmbossMask::Emboss(dst, light);
103
104 // restore original alpha
105 memcpy(dst->fImage, src.fImage, src.computeImageSize());
106
107 return true;
108 }
109
CreateProc(SkReadBuffer & buffer)110 sk_sp<SkFlattenable> SkEmbossMaskFilter::CreateProc(SkReadBuffer& buffer) {
111 Light light;
112 if (buffer.readByteArray(&light, sizeof(Light))) {
113 light.fPad = 0; // for the font-cache lookup to be clean
114 const SkScalar sigma = buffer.readScalar();
115 return Make(sigma, light);
116 }
117 return nullptr;
118 }
119
flatten(SkWriteBuffer & buffer) const120 void SkEmbossMaskFilter::flatten(SkWriteBuffer& buffer) const {
121 Light tmpLight = fLight;
122 tmpLight.fPad = 0; // for the font-cache lookup to be clean
123 buffer.writeByteArray(&tmpLight, sizeof(tmpLight));
124 buffer.writeScalar(fBlurSigma);
125 }
126
127 #ifndef SK_IGNORE_TO_STRING
toString(SkString * str) const128 void SkEmbossMaskFilter::toString(SkString* str) const {
129 str->append("SkEmbossMaskFilter: (");
130
131 str->append("direction: (");
132 str->appendScalar(fLight.fDirection[0]);
133 str->append(", ");
134 str->appendScalar(fLight.fDirection[1]);
135 str->append(", ");
136 str->appendScalar(fLight.fDirection[2]);
137 str->append(") ");
138
139 str->appendf("ambient: %d specular: %d ",
140 fLight.fAmbient, fLight.fSpecular);
141
142 str->append("blurSigma: ");
143 str->appendScalar(fBlurSigma);
144 str->append(")");
145 }
146 #endif
147