1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
/*
* Copyright 2014 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "GrBicubicEffect.h"
#include "gl/GrGLShaderBuilder.h"
#define DS(x) SkDoubleToScalar(x)
const SkScalar GrBicubicEffect::gMitchellCoefficients[16] = {
DS( 1.0 / 18.0), DS(-9.0 / 18.0), DS( 15.0 / 18.0), DS( -7.0 / 18.0),
DS(16.0 / 18.0), DS( 0.0 / 18.0), DS(-36.0 / 18.0), DS( 21.0 / 18.0),
DS( 1.0 / 18.0), DS( 9.0 / 18.0), DS( 27.0 / 18.0), DS(-21.0 / 18.0),
DS( 0.0 / 18.0), DS( 0.0 / 18.0), DS( -6.0 / 18.0), DS( 7.0 / 18.0),
};
class GrGLBicubicEffect : public GrGLEffect {
public:
GrGLBicubicEffect(const GrBackendEffectFactory& factory,
const GrDrawEffect&);
virtual void emitCode(GrGLShaderBuilder*,
const GrDrawEffect&,
const GrEffectKey&,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray&,
const TextureSamplerArray&) SK_OVERRIDE;
virtual void setData(const GrGLProgramDataManager&, const GrDrawEffect&) SK_OVERRIDE;
static inline void GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&,
GrEffectKeyBuilder* b) {
const GrTextureDomain& domain = drawEffect.castEffect<GrBicubicEffect>().domain();
b->add32(GrTextureDomain::GLDomain::DomainKey(domain));
}
private:
typedef GrGLProgramDataManager::UniformHandle UniformHandle;
UniformHandle fCoefficientsUni;
UniformHandle fImageIncrementUni;
GrTextureDomain::GLDomain fDomain;
typedef GrGLEffect INHERITED;
};
GrGLBicubicEffect::GrGLBicubicEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&)
: INHERITED(factory) {
}
void GrGLBicubicEffect::emitCode(GrGLShaderBuilder* builder,
const GrDrawEffect& drawEffect,
const GrEffectKey& key,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray& coords,
const TextureSamplerArray& samplers) {
const GrTextureDomain& domain = drawEffect.castEffect<GrBicubicEffect>().domain();
SkString coords2D = builder->ensureFSCoords2D(coords, 0);
fCoefficientsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kMat44f_GrSLType, "Coefficients");
fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
kVec2f_GrSLType, "ImageIncrement");
const char* imgInc = builder->getUniformCStr(fImageIncrementUni);
const char* coeff = builder->getUniformCStr(fCoefficientsUni);
SkString cubicBlendName;
static const GrGLShaderVar gCubicBlendArgs[] = {
GrGLShaderVar("coefficients", kMat44f_GrSLType),
GrGLShaderVar("t", kFloat_GrSLType),
GrGLShaderVar("c0", kVec4f_GrSLType),
GrGLShaderVar("c1", kVec4f_GrSLType),
GrGLShaderVar("c2", kVec4f_GrSLType),
GrGLShaderVar("c3", kVec4f_GrSLType),
};
builder->fsEmitFunction(kVec4f_GrSLType,
"cubicBlend",
SK_ARRAY_COUNT(gCubicBlendArgs),
gCubicBlendArgs,
"\tvec4 ts = vec4(1.0, t, t * t, t * t * t);\n"
"\tvec4 c = coefficients * ts;\n"
"\treturn c.x * c0 + c.y * c1 + c.z * c2 + c.w * c3;\n",
&cubicBlendName);
builder->fsCodeAppendf("\tvec2 coord = %s - %s * vec2(0.5);\n", coords2D.c_str(), imgInc);
// We unnormalize the coord in order to determine our fractional offset (f) within the texel
// We then snap coord to a texel center and renormalize. The snap prevents cases where the
// starting coords are near a texel boundary and accumulations of imgInc would cause us to skip/
// double hit a texel.
builder->fsCodeAppendf("\tcoord /= %s;\n", imgInc);
builder->fsCodeAppend("\tvec2 f = fract(coord);\n");
builder->fsCodeAppendf("\tcoord = (coord - f + vec2(0.5)) * %s;\n", imgInc);
builder->fsCodeAppend("\tvec4 rowColors[4];\n");
for (int y = 0; y < 4; ++y) {
for (int x = 0; x < 4; ++x) {
SkString coord;
coord.printf("coord + %s * vec2(%d, %d)", imgInc, x - 1, y - 1);
SkString sampleVar;
sampleVar.printf("rowColors[%d]", x);
fDomain.sampleTexture(builder, domain, sampleVar.c_str(), coord, samplers[0]);
}
builder->fsCodeAppendf("\tvec4 s%d = %s(%s, f.x, rowColors[0], rowColors[1], rowColors[2], rowColors[3]);\n", y, cubicBlendName.c_str(), coeff);
}
SkString bicubicColor;
bicubicColor.printf("%s(%s, f.y, s0, s1, s2, s3)", cubicBlendName.c_str(), coeff);
builder->fsCodeAppendf("\t%s = %s;\n", outputColor, (GrGLSLExpr4(bicubicColor.c_str()) * GrGLSLExpr4(inputColor)).c_str());
}
void GrGLBicubicEffect::setData(const GrGLProgramDataManager& pdman,
const GrDrawEffect& drawEffect) {
const GrBicubicEffect& effect = drawEffect.castEffect<GrBicubicEffect>();
const GrTexture& texture = *effect.texture(0);
float imageIncrement[2];
imageIncrement[0] = 1.0f / texture.width();
imageIncrement[1] = 1.0f / texture.height();
pdman.set2fv(fImageIncrementUni, 1, imageIncrement);
pdman.setMatrix4f(fCoefficientsUni, effect.coefficients());
fDomain.setData(pdman, effect.domain(), texture.origin());
}
static inline void convert_row_major_scalar_coeffs_to_column_major_floats(float dst[16],
const SkScalar src[16]) {
for (int y = 0; y < 4; y++) {
for (int x = 0; x < 4; x++) {
dst[x * 4 + y] = SkScalarToFloat(src[y * 4 + x]);
}
}
}
GrBicubicEffect::GrBicubicEffect(GrTexture* texture,
const SkScalar coefficients[16],
const SkMatrix &matrix,
const SkShader::TileMode tileModes[2])
: INHERITED(texture, matrix, GrTextureParams(tileModes, GrTextureParams::kNone_FilterMode))
, fDomain(GrTextureDomain::IgnoredDomain()) {
convert_row_major_scalar_coeffs_to_column_major_floats(fCoefficients, coefficients);
}
GrBicubicEffect::GrBicubicEffect(GrTexture* texture,
const SkScalar coefficients[16],
const SkMatrix &matrix,
const SkRect& domain)
: INHERITED(texture, matrix, GrTextureParams(SkShader::kClamp_TileMode,
GrTextureParams::kNone_FilterMode))
, fDomain(domain, GrTextureDomain::kClamp_Mode) {
convert_row_major_scalar_coeffs_to_column_major_floats(fCoefficients, coefficients);
}
GrBicubicEffect::~GrBicubicEffect() {
}
const GrBackendEffectFactory& GrBicubicEffect::getFactory() const {
return GrTBackendEffectFactory<GrBicubicEffect>::getInstance();
}
bool GrBicubicEffect::onIsEqual(const GrEffect& sBase) const {
const GrBicubicEffect& s = CastEffect<GrBicubicEffect>(sBase);
return this->textureAccess(0) == s.textureAccess(0) &&
!memcmp(fCoefficients, s.coefficients(), 16) &&
fDomain == s.fDomain;
}
void GrBicubicEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
// FIXME: Perhaps we can do better.
*validFlags = 0;
return;
}
GR_DEFINE_EFFECT_TEST(GrBicubicEffect);
GrEffect* GrBicubicEffect::TestCreate(SkRandom* random,
GrContext* context,
const GrDrawTargetCaps&,
GrTexture* textures[]) {
int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
GrEffectUnitTest::kAlphaTextureIdx;
SkScalar coefficients[16];
for (int i = 0; i < 16; i++) {
coefficients[i] = random->nextSScalar1();
}
return GrBicubicEffect::Create(textures[texIdx], coefficients);
}
//////////////////////////////////////////////////////////////////////////////
bool GrBicubicEffect::ShouldUseBicubic(const SkMatrix& matrix,
GrTextureParams::FilterMode* filterMode) {
if (matrix.isIdentity()) {
*filterMode = GrTextureParams::kNone_FilterMode;
return false;
}
SkScalar scales[2];
if (!matrix.getMinMaxScales(scales) || scales[0] < SK_Scalar1) {
// Bicubic doesn't handle arbitrary minimization well, as src texels can be skipped
// entirely,
*filterMode = GrTextureParams::kMipMap_FilterMode;
return false;
}
// At this point if scales[1] == SK_Scalar1 then the matrix doesn't do any scaling.
if (scales[1] == SK_Scalar1) {
if (matrix.rectStaysRect() && SkScalarIsInt(matrix.getTranslateX()) &&
SkScalarIsInt(matrix.getTranslateY())) {
*filterMode = GrTextureParams::kNone_FilterMode;
} else {
// Use bilerp to handle rotation or fractional translation.
*filterMode = GrTextureParams::kBilerp_FilterMode;
}
return false;
}
// When we use the bicubic filtering effect each sample is read from the texture using
// nearest neighbor sampling.
*filterMode = GrTextureParams::kNone_FilterMode;
return true;
}
|
