| /* | 
 |  * Copyright 2017 Google Inc. | 
 |  * | 
 |  * Use of this source code is governed by a BSD-style license that can be | 
 |  * found in the LICENSE file. | 
 |  */ | 
 |  | 
 | #include "include/core/SkCanvas.h" | 
 | #include "include/core/SkPaint.h" | 
 | #include "include/core/SkPath.h" | 
 | #include "include/utils/SkRandom.h" | 
 | #include "samplecode/Sample.h" | 
 | #include "src/core/SkPathPriv.h" | 
 | #include "src/core/SkScalerCache.h" | 
 | #include "src/core/SkStrikeCache.h" | 
 | #include "src/core/SkStrikeSpec.h" | 
 | #include "src/core/SkTaskGroup.h" | 
 | #include "tools/ToolUtils.h" | 
 |  | 
 | //////////////////////////////////////////////////////////////////////////////////////////////////// | 
 | // Static text from paths. | 
 | class PathText : public Sample { | 
 | public: | 
 |     constexpr static int kNumPaths = 1500; | 
 |     virtual const char* getName() const { return "PathText"; } | 
 |  | 
 |     PathText() {} | 
 |  | 
 |     virtual void reset() { | 
 |         for (Glyph& glyph : fGlyphs) { | 
 |             glyph.reset(fRand, this->width(), this->height()); | 
 |         } | 
 |         fGlyphAnimator->reset(&fRand, this->width(), this->height()); | 
 |     } | 
 |  | 
 |     void onOnceBeforeDraw() final { | 
 |         SkFont defaultFont; | 
 |         SkStrikeSpec strikeSpec = SkStrikeSpec::MakeWithNoDevice(defaultFont); | 
 |         auto strike = strikeSpec.findOrCreateStrike(); | 
 |         SkPath glyphPaths[52]; | 
 |         for (int i = 0; i < 52; ++i) { | 
 |             // I and l are rects on OS X ... | 
 |             char c = "aQCDEFGH7JKLMNOPBRZTUVWXYSAbcdefghijk1mnopqrstuvwxyz"[i]; | 
 |             SkPackedGlyphID id(defaultFont.unicharToGlyph(c)); | 
 |             sk_ignore_unused_variable(strike->getScalerContext()->getPath(id, &glyphPaths[i])); | 
 |         } | 
 |  | 
 |         for (int i = 0; i < kNumPaths; ++i) { | 
 |             const SkPath& p = glyphPaths[i % 52]; | 
 |             fGlyphs[i].init(fRand, p); | 
 |         } | 
 |  | 
 |         this->Sample::onOnceBeforeDraw(); | 
 |         this->reset(); | 
 |     } | 
 |     void onSizeChange() final { this->Sample::onSizeChange(); this->reset(); } | 
 |  | 
 |     SkString name() override { return SkString(this->getName()); } | 
 |  | 
 |     bool onChar(SkUnichar) override; | 
 |  | 
 |     bool onAnimate(double nanos) final { | 
 |         return fGlyphAnimator->animate(nanos, this->width(), this->height()); | 
 |     } | 
 |  | 
 |     void onDrawContent(SkCanvas* canvas) override { | 
 |         if (fDoClip) { | 
 |             SkPath deviceSpaceClipPath = fClipPath; | 
 |             deviceSpaceClipPath.transform(SkMatrix::Scale(this->width(), this->height())); | 
 |             canvas->save(); | 
 |             canvas->clipPath(deviceSpaceClipPath, SkClipOp::kDifference, true); | 
 |             canvas->clear(SK_ColorBLACK); | 
 |             canvas->restore(); | 
 |             canvas->clipPath(deviceSpaceClipPath, SkClipOp::kIntersect, true); | 
 |         } | 
 |         fGlyphAnimator->draw(canvas); | 
 |     } | 
 |  | 
 | protected: | 
 |     struct Glyph { | 
 |         void init(SkRandom& rand, const SkPath& path); | 
 |         void reset(SkRandom& rand, int w, int h); | 
 |  | 
 |         SkPath     fPath; | 
 |         SkPaint    fPaint; | 
 |         SkPoint    fPosition; | 
 |         SkScalar   fZoom; | 
 |         SkScalar   fSpin; | 
 |         SkPoint    fMidpt; | 
 |     }; | 
 |  | 
 |     class GlyphAnimator { | 
 |     public: | 
 |         GlyphAnimator(Glyph* glyphs) : fGlyphs(glyphs) {} | 
 |         virtual void reset(SkRandom*, int screenWidth, int screenHeight) {} | 
 |         virtual bool animate(double nanos, int screenWidth, int screenHeight) { return false; } | 
 |         virtual void draw(SkCanvas* canvas) { | 
 |             for (int i = 0; i < kNumPaths; ++i) { | 
 |                 Glyph& glyph = fGlyphs[i]; | 
 |                 SkAutoCanvasRestore acr(canvas, true); | 
 |                 canvas->translate(glyph.fPosition.x(), glyph.fPosition.y()); | 
 |                 canvas->scale(glyph.fZoom, glyph.fZoom); | 
 |                 canvas->rotate(glyph.fSpin); | 
 |                 canvas->translate(-glyph.fMidpt.x(), -glyph.fMidpt.y()); | 
 |                 canvas->drawPath(glyph.fPath, glyph.fPaint); | 
 |             } | 
 |         } | 
 |         virtual ~GlyphAnimator() {} | 
 |  | 
 |     protected: | 
 |         Glyph* const fGlyphs; | 
 |     }; | 
 |  | 
 |     class MovingGlyphAnimator; | 
 |     class WavyGlyphAnimator; | 
 |  | 
 |     Glyph fGlyphs[kNumPaths]; | 
 |     SkRandom fRand{25}; | 
 |     SkPath fClipPath = ToolUtils::make_star(SkRect{0, 0, 1, 1}, 11, 3); | 
 |     bool fDoClip = false; | 
 |     std::unique_ptr<GlyphAnimator> fGlyphAnimator = std::make_unique<GlyphAnimator>(fGlyphs); | 
 | }; | 
 |  | 
 | void PathText::Glyph::init(SkRandom& rand, const SkPath& path) { | 
 |     fPath = path; | 
 |     fPaint.setAntiAlias(true); | 
 |     fPaint.setColor(rand.nextU() | 0x80808080); | 
 | } | 
 |  | 
 | void PathText::Glyph::reset(SkRandom& rand, int w, int h) { | 
 |     int screensize = std::max(w, h); | 
 |     const SkRect& bounds = fPath.getBounds(); | 
 |     SkScalar t; | 
 |  | 
 |     fPosition = {rand.nextF() * w, rand.nextF() * h}; | 
 |     t = pow(rand.nextF(), 100); | 
 |     fZoom = ((1 - t) * screensize / 50 + t * screensize / 3) / | 
 |             std::max(bounds.width(), bounds.height()); | 
 |     fSpin = rand.nextF() * 360; | 
 |     fMidpt = {bounds.centerX(), bounds.centerY()}; | 
 | } | 
 |  | 
 | //////////////////////////////////////////////////////////////////////////////////////////////////// | 
 | // Text from paths with animated transformation matrices. | 
 | class PathText::MovingGlyphAnimator : public PathText::GlyphAnimator { | 
 | public: | 
 |     MovingGlyphAnimator(Glyph* glyphs) | 
 |             : GlyphAnimator(glyphs) | 
 |             , fFrontMatrices(kNumPaths) | 
 |             , fBackMatrices(kNumPaths) { | 
 |     } | 
 |  | 
 |     ~MovingGlyphAnimator() override { | 
 |         fBackgroundAnimationTask.wait(); | 
 |     } | 
 |  | 
 |     void reset(SkRandom* rand, int screenWidth, int screenHeight) override { | 
 |         const SkScalar screensize = static_cast<SkScalar>(std::max(screenWidth, screenHeight)); | 
 |  | 
 |         for (auto& v : fVelocities) { | 
 |             for (SkScalar* d : {&v.fDx, &v.fDy}) { | 
 |                 SkScalar t = pow(rand->nextF(), 3); | 
 |                 *d = ((1 - t) / 60 + t / 10) * (rand->nextBool() ? screensize : -screensize); | 
 |             } | 
 |  | 
 |             SkScalar t = pow(rand->nextF(), 25); | 
 |             v.fDSpin = ((1 - t) * 360 / 7.5 + t * 360 / 1.5) * (rand->nextBool() ? 1 : -1); | 
 |         } | 
 |  | 
 |         // Get valid front data. | 
 |         fBackgroundAnimationTask.wait(); | 
 |         this->runAnimationTask(0, 0, screenWidth, screenHeight); | 
 |         memcpy(fFrontMatrices, fBackMatrices, kNumPaths * sizeof(SkMatrix)); | 
 |         fLastTick = 0; | 
 |     } | 
 |  | 
 |     bool animate(double nanos, int screenWidth, int screenHeight) final { | 
 |         fBackgroundAnimationTask.wait(); | 
 |         this->swapAnimationBuffers(); | 
 |  | 
 |         const double tsec = 1e-9 * nanos; | 
 |         const double dt = fLastTick ? (1e-9 * nanos - fLastTick) : 0; | 
 |         fBackgroundAnimationTask.add(std::bind(&MovingGlyphAnimator::runAnimationTask, this, tsec, | 
 |                                                dt, screenWidth, screenHeight)); | 
 |         fLastTick = 1e-9 * nanos; | 
 |         return true; | 
 |     } | 
 |  | 
 |     /** | 
 |      * Called on a background thread. Here we can only modify fBackMatrices. | 
 |      */ | 
 |     virtual void runAnimationTask(double t, double dt, int w, int h) { | 
 |         for (int idx = 0; idx < kNumPaths; ++idx) { | 
 |             Velocity* v = &fVelocities[idx]; | 
 |             Glyph* glyph = &fGlyphs[idx]; | 
 |             SkMatrix* backMatrix = &fBackMatrices[idx]; | 
 |  | 
 |             glyph->fPosition.fX += v->fDx * dt; | 
 |             if (glyph->fPosition.x() < 0) { | 
 |                 glyph->fPosition.fX -= 2 * glyph->fPosition.x(); | 
 |                 v->fDx = -v->fDx; | 
 |             } else if (glyph->fPosition.x() > w) { | 
 |                 glyph->fPosition.fX -= 2 * (glyph->fPosition.x() - w); | 
 |                 v->fDx = -v->fDx; | 
 |             } | 
 |  | 
 |             glyph->fPosition.fY += v->fDy * dt; | 
 |             if (glyph->fPosition.y() < 0) { | 
 |                 glyph->fPosition.fY -= 2 * glyph->fPosition.y(); | 
 |                 v->fDy = -v->fDy; | 
 |             } else if (glyph->fPosition.y() > h) { | 
 |                 glyph->fPosition.fY -= 2 * (glyph->fPosition.y() - h); | 
 |                 v->fDy = -v->fDy; | 
 |             } | 
 |  | 
 |             glyph->fSpin += v->fDSpin * dt; | 
 |  | 
 |             backMatrix->setTranslate(glyph->fPosition.x(), glyph->fPosition.y()); | 
 |             backMatrix->preScale(glyph->fZoom, glyph->fZoom); | 
 |             backMatrix->preRotate(glyph->fSpin); | 
 |             backMatrix->preTranslate(-glyph->fMidpt.x(), -glyph->fMidpt.y()); | 
 |         } | 
 |     } | 
 |  | 
 |     virtual void swapAnimationBuffers() { | 
 |         std::swap(fFrontMatrices, fBackMatrices); | 
 |     } | 
 |  | 
 |     void draw(SkCanvas* canvas) override { | 
 |         for (int i = 0; i < kNumPaths; ++i) { | 
 |             SkAutoCanvasRestore acr(canvas, true); | 
 |             canvas->concat(fFrontMatrices[i]); | 
 |             canvas->drawPath(fGlyphs[i].fPath, fGlyphs[i].fPaint); | 
 |         } | 
 |     } | 
 |  | 
 | protected: | 
 |     struct Velocity { | 
 |         SkScalar fDx, fDy; | 
 |         SkScalar fDSpin; | 
 |     }; | 
 |  | 
 |     Velocity fVelocities[kNumPaths]; | 
 |     SkAutoTMalloc<SkMatrix> fFrontMatrices; | 
 |     SkAutoTMalloc<SkMatrix> fBackMatrices; | 
 |     SkTaskGroup fBackgroundAnimationTask; | 
 |     double fLastTick; | 
 | }; | 
 |  | 
 |  | 
 | //////////////////////////////////////////////////////////////////////////////////////////////////// | 
 | // Text from paths with animated control points. | 
 | class PathText::WavyGlyphAnimator : public PathText::MovingGlyphAnimator { | 
 | public: | 
 |     WavyGlyphAnimator(Glyph* glyphs) | 
 |             : MovingGlyphAnimator(glyphs) | 
 |             , fFrontPaths(kNumPaths) | 
 |             , fBackPaths(kNumPaths) { | 
 |     } | 
 |  | 
 |     ~WavyGlyphAnimator() override { | 
 |         fBackgroundAnimationTask.wait(); | 
 |     } | 
 |  | 
 |     void reset(SkRandom* rand, int screenWidth, int screenHeight) override { | 
 |         fWaves.reset(*rand, screenWidth, screenHeight); | 
 |         this->MovingGlyphAnimator::reset(rand, screenWidth, screenHeight); | 
 |         std::copy(fBackPaths.get(), fBackPaths.get() + kNumPaths, fFrontPaths.get()); | 
 |     } | 
 |  | 
 |     /** | 
 |      * Called on a background thread. Here we can only modify fBackPaths. | 
 |      */ | 
 |     void runAnimationTask(double t, double dt, int w, int h) override { | 
 |         const float tsec = static_cast<float>(t); | 
 |         this->MovingGlyphAnimator::runAnimationTask(t, 0.5 * dt, w, h); | 
 |  | 
 |         for (int i = 0; i < kNumPaths; ++i) { | 
 |             const Glyph& glyph = fGlyphs[i]; | 
 |             const SkMatrix& backMatrix = fBackMatrices[i]; | 
 |  | 
 |             const Sk2f matrix[3] = { | 
 |                 Sk2f(backMatrix.getScaleX(), backMatrix.getSkewY()), | 
 |                 Sk2f(backMatrix.getSkewX(), backMatrix.getScaleY()), | 
 |                 Sk2f(backMatrix.getTranslateX(), backMatrix.getTranslateY()) | 
 |             }; | 
 |  | 
 |             SkPath* backpath = &fBackPaths[i]; | 
 |             backpath->reset(); | 
 |             backpath->setFillType(SkPathFillType::kEvenOdd); | 
 |  | 
 |             for (auto [verb, pts, w] : SkPathPriv::Iterate(glyph.fPath)) { | 
 |                 switch (verb) { | 
 |                     case SkPathVerb::kMove: { | 
 |                         SkPoint pt = fWaves.apply(tsec, matrix, pts[0]); | 
 |                         backpath->moveTo(pt.x(), pt.y()); | 
 |                         break; | 
 |                     } | 
 |                     case SkPathVerb::kLine: { | 
 |                         SkPoint endpt = fWaves.apply(tsec, matrix, pts[1]); | 
 |                         backpath->lineTo(endpt.x(), endpt.y()); | 
 |                         break; | 
 |                     } | 
 |                     case SkPathVerb::kQuad: { | 
 |                         SkPoint controlPt = fWaves.apply(tsec, matrix, pts[1]); | 
 |                         SkPoint endpt = fWaves.apply(tsec, matrix, pts[2]); | 
 |                         backpath->quadTo(controlPt.x(), controlPt.y(), endpt.x(), endpt.y()); | 
 |                         break; | 
 |                     } | 
 |                     case SkPathVerb::kClose: { | 
 |                         backpath->close(); | 
 |                         break; | 
 |                     } | 
 |                     case SkPathVerb::kCubic: | 
 |                     case SkPathVerb::kConic: | 
 |                         SK_ABORT("Unexpected path verb"); | 
 |                         break; | 
 |                 } | 
 |             } | 
 |         } | 
 |     } | 
 |  | 
 |     void swapAnimationBuffers() override { | 
 |         this->MovingGlyphAnimator::swapAnimationBuffers(); | 
 |         std::swap(fFrontPaths, fBackPaths); | 
 |     } | 
 |  | 
 |     void draw(SkCanvas* canvas) override { | 
 |         for (int i = 0; i < kNumPaths; ++i) { | 
 |             canvas->drawPath(fFrontPaths[i], fGlyphs[i].fPaint); | 
 |         } | 
 |     } | 
 |  | 
 | private: | 
 |     /** | 
 |      * Describes 4 stacked sine waves that can offset a point as a function of wall time. | 
 |      */ | 
 |     class Waves { | 
 |     public: | 
 |         void reset(SkRandom& rand, int w, int h); | 
 |         SkPoint apply(float tsec, const Sk2f matrix[3], const SkPoint& pt) const; | 
 |  | 
 |     private: | 
 |         constexpr static double kAverageAngle = SK_ScalarPI / 8.0; | 
 |         constexpr static double kMaxOffsetAngle = SK_ScalarPI / 3.0; | 
 |  | 
 |         float fAmplitudes[4]; | 
 |         float fFrequencies[4]; | 
 |         float fDirsX[4]; | 
 |         float fDirsY[4]; | 
 |         float fSpeeds[4]; | 
 |         float fOffsets[4]; | 
 |     }; | 
 |  | 
 |     SkAutoTArray<SkPath> fFrontPaths; | 
 |     SkAutoTArray<SkPath> fBackPaths; | 
 |     Waves fWaves; | 
 | }; | 
 |  | 
 | void PathText::WavyGlyphAnimator::Waves::reset(SkRandom& rand, int w, int h) { | 
 |     const double pixelsPerMeter = 0.06 * std::max(w, h); | 
 |     const double medianWavelength = 8 * pixelsPerMeter; | 
 |     const double medianWaveAmplitude = 0.05 * 4 * pixelsPerMeter; | 
 |     const double gravity = 9.8 * pixelsPerMeter; | 
 |  | 
 |     for (int i = 0; i < 4; ++i) { | 
 |         const double offsetAngle = (rand.nextF() * 2 - 1) * kMaxOffsetAngle; | 
 |         const double intensity = pow(2, rand.nextF() * 2 - 1); | 
 |         const double wavelength = intensity * medianWavelength; | 
 |  | 
 |         fAmplitudes[i] = intensity * medianWaveAmplitude; | 
 |         fFrequencies[i] = 2 * SK_ScalarPI / wavelength; | 
 |         fDirsX[i] = cosf(kAverageAngle + offsetAngle); | 
 |         fDirsY[i] = sinf(kAverageAngle + offsetAngle); | 
 |         fSpeeds[i] = -sqrt(gravity * 2 * SK_ScalarPI / wavelength); | 
 |         fOffsets[i] = rand.nextF() * 2 * SK_ScalarPI; | 
 |     } | 
 | } | 
 |  | 
 | SkPoint PathText::WavyGlyphAnimator::Waves::apply(float tsec, const Sk2f matrix[3], | 
 |                                                   const SkPoint& pt) const { | 
 |     constexpr static int kTablePeriod = 1 << 12; | 
 |     static float sin2table[kTablePeriod + 1]; | 
 |     static SkOnce initTable; | 
 |     initTable([]() { | 
 |         for (int i = 0; i <= kTablePeriod; ++i) { | 
 |             const double sintheta = sin(i * (SK_ScalarPI / kTablePeriod)); | 
 |             sin2table[i] = static_cast<float>(sintheta * sintheta - 0.5); | 
 |         } | 
 |     }); | 
 |  | 
 |      const Sk4f amplitudes = Sk4f::Load(fAmplitudes); | 
 |      const Sk4f frequencies = Sk4f::Load(fFrequencies); | 
 |      const Sk4f dirsX = Sk4f::Load(fDirsX); | 
 |      const Sk4f dirsY = Sk4f::Load(fDirsY); | 
 |      const Sk4f speeds = Sk4f::Load(fSpeeds); | 
 |      const Sk4f offsets = Sk4f::Load(fOffsets); | 
 |  | 
 |     float devicePt[2]; | 
 |     (matrix[0] * pt.x() + matrix[1] * pt.y() + matrix[2]).store(devicePt); | 
 |  | 
 |     const Sk4f t = (frequencies * (dirsX * devicePt[0] + dirsY * devicePt[1]) + | 
 |                     speeds * tsec + | 
 |                     offsets).abs() * (float(kTablePeriod) / float(SK_ScalarPI)); | 
 |  | 
 |     const Sk4i ipart = SkNx_cast<int>(t); | 
 |     const Sk4f fpart = t - SkNx_cast<float>(ipart); | 
 |  | 
 |     int32_t indices[4]; | 
 |     (ipart & (kTablePeriod-1)).store(indices); | 
 |  | 
 |     const Sk4f left(sin2table[indices[0]], sin2table[indices[1]], | 
 |                     sin2table[indices[2]], sin2table[indices[3]]); | 
 |     const Sk4f right(sin2table[indices[0] + 1], sin2table[indices[1] + 1], | 
 |                      sin2table[indices[2] + 1], sin2table[indices[3] + 1]); | 
 |     const Sk4f height = amplitudes * (left * (1.f - fpart) + right * fpart); | 
 |  | 
 |     Sk4f dy = height * dirsY; | 
 |     Sk4f dx = height * dirsX; | 
 |  | 
 |     float offsetY[4], offsetX[4]; | 
 |     (dy + SkNx_shuffle<2,3,0,1>(dy)).store(offsetY); // accumulate. | 
 |     (dx + SkNx_shuffle<2,3,0,1>(dx)).store(offsetX); | 
 |  | 
 |     return {devicePt[0] + offsetY[0] + offsetY[1], devicePt[1] - offsetX[0] - offsetX[1]}; | 
 | } | 
 |  | 
 | bool PathText::onChar(SkUnichar unichar) { | 
 |     switch (unichar) { | 
 |         case 'X': | 
 |             fDoClip = !fDoClip; | 
 |             return true; | 
 |         case 'S': | 
 |             fGlyphAnimator = std::make_unique<GlyphAnimator>(fGlyphs); | 
 |             fGlyphAnimator->reset(&fRand, this->width(), this->height()); | 
 |             return true; | 
 |         case 'M': | 
 |             fGlyphAnimator = std::make_unique<MovingGlyphAnimator>(fGlyphs); | 
 |             fGlyphAnimator->reset(&fRand, this->width(), this->height()); | 
 |             return true; | 
 |         case 'W': | 
 |             fGlyphAnimator = std::make_unique<WavyGlyphAnimator>(fGlyphs); | 
 |             fGlyphAnimator->reset(&fRand, this->width(), this->height()); | 
 |             return true; | 
 |     } | 
 |     return false; | 
 | } | 
 |  | 
 | //////////////////////////////////////////////////////////////////////////////////////////////////// | 
 |  | 
 | Sample* MakePathTextSample() { return new PathText; } | 
 | static SampleRegistry gPathTextSample(MakePathTextSample); |