1/*
2 * Copyright 2012 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 "GrTextureDomain.h"
9#include "GrSimpleTextureEffect.h"
10#include "GrTBackendEffectFactory.h"
11#include "gl/GrGLEffect.h"
12#include "SkFloatingPoint.h"
13
14
15GrTextureDomain::GrTextureDomain(const SkRect& domain, Mode mode, int index)
16    : fIndex(index) {
17
18    static const SkRect kFullRect = {0, 0, SK_Scalar1, SK_Scalar1};
19    if (domain.contains(kFullRect)) {
20        fMode = kIgnore_Mode;
21    } else {
22        fMode = mode;
23    }
24
25    if (fMode != kIgnore_Mode) {
26        // We don't currently handle domains that are empty or don't intersect the texture.
27        // It is OK if the domain rect is a line or point, but it should not be inverted. We do not
28        // handle rects that do not intersect the [0..1]x[0..1] rect.
29        SkASSERT(domain.fLeft <= domain.fRight);
30        SkASSERT(domain.fTop <= domain.fBottom);
31        fDomain.fLeft = SkMaxScalar(domain.fLeft, kFullRect.fLeft);
32        fDomain.fRight = SkMinScalar(domain.fRight, kFullRect.fRight);
33        fDomain.fTop = SkMaxScalar(domain.fTop, kFullRect.fTop);
34        fDomain.fBottom = SkMinScalar(domain.fBottom, kFullRect.fBottom);
35        SkASSERT(fDomain.fLeft <= fDomain.fRight);
36        SkASSERT(fDomain.fTop <= fDomain.fBottom);
37    }
38}
39
40//////////////////////////////////////////////////////////////////////////////
41
42void GrTextureDomain::GLDomain::sampleTexture(GrGLShaderBuilder* builder,
43                                              const GrTextureDomain& textureDomain,
44                                              const char* outColor,
45                                              const SkString& inCoords,
46                                              const GrGLEffect::TextureSampler sampler,
47                                              const char* inModulateColor) {
48    SkASSERT((Mode)-1 == fMode || textureDomain.mode() == fMode);
49    SkDEBUGCODE(fMode = textureDomain.mode();)
50
51    if (kIgnore_Mode == textureDomain.mode()) {
52        builder->fsCodeAppendf("\t%s = ", outColor);
53        builder->fsAppendTextureLookupAndModulate(inModulateColor, sampler,
54                                                    inCoords.c_str());
55        builder->fsCodeAppend(";\n");
56        return;
57    }
58
59    if (!fDomainUni.isValid()) {
60        const char* name;
61        SkString uniName("TexDom");
62        if (textureDomain.fIndex >= 0) {
63            uniName.appendS32(textureDomain.fIndex);
64        }
65        fDomainUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
66                                            kVec4f_GrSLType, uniName.c_str(), &name);
67        fDomainName = name;
68    }
69    if (kClamp_Mode == textureDomain.mode()) {
70        SkString clampedCoords;
71        clampedCoords.appendf("\tclamp(%s, %s.xy, %s.zw)",
72                                inCoords.c_str(), fDomainName.c_str(), fDomainName.c_str());
73
74        builder->fsCodeAppendf("\t%s = ", outColor);
75        builder->fsAppendTextureLookupAndModulate(inModulateColor, sampler, clampedCoords.c_str());
76        builder->fsCodeAppend(";\n");
77    } else {
78        SkASSERT(GrTextureDomain::kDecal_Mode == textureDomain.mode());
79        // Add a block since we're going to declare variables.
80        GrGLShaderBuilder::FSBlock block(builder);
81
82        const char* domain = fDomainName.c_str();
83        if (kImagination_GrGLVendor == builder->ctxInfo().vendor()) {
84            // On the NexusS and GalaxyNexus, the other path (with the 'any'
85            // call) causes the compilation error "Calls to any function that
86            // may require a gradient calculation inside a conditional block
87            // may return undefined results". This appears to be an issue with
88            // the 'any' call since even the simple "result=black; if (any())
89            // result=white;" code fails to compile.
90            builder->fsCodeAppend("\tvec4 outside = vec4(0.0, 0.0, 0.0, 0.0);\n");
91            builder->fsCodeAppend("\tvec4 inside = ");
92            builder->fsAppendTextureLookupAndModulate(inModulateColor, sampler, inCoords.c_str());
93            builder->fsCodeAppend(";\n");
94
95            builder->fsCodeAppendf("\tfloat x = abs(2.0*(%s.x - %s.x)/(%s.z - %s.x) - 1.0);\n",
96                                    inCoords.c_str(), domain, domain, domain);
97            builder->fsCodeAppendf("\tfloat y = abs(2.0*(%s.y - %s.y)/(%s.w - %s.y) - 1.0);\n",
98                                    inCoords.c_str(), domain, domain, domain);
99            builder->fsCodeAppend("\tfloat blend = step(1.0, max(x, y));\n");
100            builder->fsCodeAppendf("\t%s = mix(inside, outside, blend);\n", outColor);
101        } else {
102            builder->fsCodeAppend("\tbvec4 outside;\n");
103            builder->fsCodeAppendf("\toutside.xy = lessThan(%s, %s.xy);\n", inCoords.c_str(),
104                                   domain);
105            builder->fsCodeAppendf("\toutside.zw = greaterThan(%s, %s.zw);\n", inCoords.c_str(),
106                                   domain);
107            builder->fsCodeAppendf("\t%s = any(outside) ? vec4(0.0, 0.0, 0.0, 0.0) : ", outColor);
108            builder->fsAppendTextureLookupAndModulate(inModulateColor, sampler, inCoords.c_str());
109            builder->fsCodeAppend(";\n");
110        }
111    }
112}
113
114void GrTextureDomain::GLDomain::setData(const GrGLUniformManager& uman,
115                                        const GrTextureDomain& textureDomain,
116                                        GrSurfaceOrigin textureOrigin) {
117    SkASSERT(textureDomain.mode() == fMode);
118    if (kIgnore_Mode != textureDomain.mode()) {
119        GrGLfloat values[4] = {
120            SkScalarToFloat(textureDomain.domain().left()),
121            SkScalarToFloat(textureDomain.domain().top()),
122            SkScalarToFloat(textureDomain.domain().right()),
123            SkScalarToFloat(textureDomain.domain().bottom())
124        };
125        // vertical flip if necessary
126        if (kBottomLeft_GrSurfaceOrigin == textureOrigin) {
127            values[1] = 1.0f - values[1];
128            values[3] = 1.0f - values[3];
129            // The top and bottom were just flipped, so correct the ordering
130            // of elements so that values = (l, t, r, b).
131            SkTSwap(values[1], values[3]);
132        }
133        if (0 != memcmp(values, fPrevDomain, 4 * sizeof(GrGLfloat))) {
134            uman.set4fv(fDomainUni, 1, values);
135            memcpy(fPrevDomain, values, 4 * sizeof(GrGLfloat));
136        }
137    }
138}
139
140
141//////////////////////////////////////////////////////////////////////////////
142
143class GrGLTextureDomainEffect : public GrGLEffect {
144public:
145    GrGLTextureDomainEffect(const GrBackendEffectFactory&, const GrDrawEffect&);
146
147    virtual void emitCode(GrGLShaderBuilder*,
148                          const GrDrawEffect&,
149                          EffectKey,
150                          const char* outputColor,
151                          const char* inputColor,
152                          const TransformedCoordsArray&,
153                          const TextureSamplerArray&) SK_OVERRIDE;
154
155    virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
156
157    static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
158
159private:
160    GrTextureDomain::GLDomain         fGLDomain;
161    typedef GrGLEffect INHERITED;
162};
163
164GrGLTextureDomainEffect::GrGLTextureDomainEffect(const GrBackendEffectFactory& factory,
165                                                 const GrDrawEffect&)
166    : INHERITED(factory) {
167}
168
169void GrGLTextureDomainEffect::emitCode(GrGLShaderBuilder* builder,
170                                       const GrDrawEffect& drawEffect,
171                                       EffectKey key,
172                                       const char* outputColor,
173                                       const char* inputColor,
174                                       const TransformedCoordsArray& coords,
175                                       const TextureSamplerArray& samplers) {
176    const GrTextureDomainEffect& effect = drawEffect.castEffect<GrTextureDomainEffect>();
177    const GrTextureDomain& domain = effect.textureDomain();
178
179    SkString coords2D = builder->ensureFSCoords2D(coords, 0);
180    fGLDomain.sampleTexture(builder, domain, outputColor, coords2D, samplers[0], inputColor);
181}
182
183void GrGLTextureDomainEffect::setData(const GrGLUniformManager& uman,
184                                      const GrDrawEffect& drawEffect) {
185    const GrTextureDomainEffect& effect = drawEffect.castEffect<GrTextureDomainEffect>();
186    const GrTextureDomain& domain = effect.textureDomain();
187    fGLDomain.setData(uman, domain, effect.texture(0)->origin());
188}
189
190GrGLEffect::EffectKey GrGLTextureDomainEffect::GenKey(const GrDrawEffect& drawEffect,
191                                                      const GrGLCaps&) {
192    const GrTextureDomain& domain = drawEffect.castEffect<GrTextureDomainEffect>().textureDomain();
193    return GrTextureDomain::GLDomain::DomainKey(domain);
194}
195
196
197///////////////////////////////////////////////////////////////////////////////
198
199GrEffectRef* GrTextureDomainEffect::Create(GrTexture* texture,
200                                           const SkMatrix& matrix,
201                                           const SkRect& domain,
202                                           GrTextureDomain::Mode mode,
203                                           GrTextureParams::FilterMode filterMode,
204                                           GrCoordSet coordSet) {
205    static const SkRect kFullRect = {0, 0, SK_Scalar1, SK_Scalar1};
206    if (GrTextureDomain::kIgnore_Mode == mode ||
207        (GrTextureDomain::kClamp_Mode == mode && domain.contains(kFullRect))) {
208        return GrSimpleTextureEffect::Create(texture, matrix, filterMode);
209    } else {
210
211        AutoEffectUnref effect(SkNEW_ARGS(GrTextureDomainEffect, (texture,
212                                                                  matrix,
213                                                                  domain,
214                                                                  mode,
215                                                                  filterMode,
216                                                                  coordSet)));
217        return CreateEffectRef(effect);
218
219    }
220}
221
222GrTextureDomainEffect::GrTextureDomainEffect(GrTexture* texture,
223                                             const SkMatrix& matrix,
224                                             const SkRect& domain,
225                                             GrTextureDomain::Mode mode,
226                                             GrTextureParams::FilterMode filterMode,
227                                             GrCoordSet coordSet)
228    : GrSingleTextureEffect(texture, matrix, filterMode, coordSet)
229    , fTextureDomain(domain, mode) {
230}
231
232GrTextureDomainEffect::~GrTextureDomainEffect() {
233
234}
235
236const GrBackendEffectFactory& GrTextureDomainEffect::getFactory() const {
237    return GrTBackendEffectFactory<GrTextureDomainEffect>::getInstance();
238}
239
240bool GrTextureDomainEffect::onIsEqual(const GrEffect& sBase) const {
241    const GrTextureDomainEffect& s = CastEffect<GrTextureDomainEffect>(sBase);
242    return this->hasSameTextureParamsMatrixAndSourceCoords(s) &&
243           this->fTextureDomain == s.fTextureDomain;
244}
245
246void GrTextureDomainEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
247    if (GrTextureDomain::kDecal_Mode == fTextureDomain.mode()) { // TODO: helper
248        *validFlags = 0;
249    } else {
250        this->updateConstantColorComponentsForModulation(color, validFlags);
251    }
252}
253
254///////////////////////////////////////////////////////////////////////////////
255
256GR_DEFINE_EFFECT_TEST(GrTextureDomainEffect);
257
258GrEffectRef* GrTextureDomainEffect::TestCreate(SkRandom* random,
259                                               GrContext*,
260                                               const GrDrawTargetCaps&,
261                                               GrTexture* textures[]) {
262    int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
263                                      GrEffectUnitTest::kAlphaTextureIdx;
264    SkRect domain;
265    domain.fLeft = random->nextUScalar1();
266    domain.fRight = random->nextRangeScalar(domain.fLeft, SK_Scalar1);
267    domain.fTop = random->nextUScalar1();
268    domain.fBottom = random->nextRangeScalar(domain.fTop, SK_Scalar1);
269    GrTextureDomain::Mode mode =
270        (GrTextureDomain::Mode) random->nextULessThan(GrTextureDomain::kModeCount);
271    const SkMatrix& matrix = GrEffectUnitTest::TestMatrix(random);
272    bool bilerp = random->nextBool();
273    GrCoordSet coords = random->nextBool() ? kLocal_GrCoordSet : kPosition_GrCoordSet;
274    return GrTextureDomainEffect::Create(textures[texIdx],
275                                         matrix,
276                                         domain,
277                                         mode,
278                                         bilerp ? GrTextureParams::kBilerp_FilterMode : GrTextureParams::kNone_FilterMode,
279                                         coords);
280}
281