| /* |
| * 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); |
| std::copy_n(fBackMatrices.get(), kNumPaths, fFrontMatrices.get()); |
| 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]; |
| SkAutoTArray<SkMatrix> fFrontMatrices; |
| SkAutoTArray<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); |