| /* |
| * Copyright 2019 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "gm/gm.h" |
| #include "include/core/SkCanvas.h" |
| #include "include/core/SkColor.h" |
| #include "include/core/SkFont.h" |
| #include "include/core/SkFontTypes.h" |
| #include "include/core/SkImage.h" |
| #include "include/core/SkM44.h" |
| #include "include/core/SkMatrix.h" |
| #include "include/core/SkPaint.h" |
| #include "include/core/SkRRect.h" |
| #include "include/core/SkRect.h" |
| #include "include/core/SkRefCnt.h" |
| #include "include/core/SkScalar.h" |
| #include "include/core/SkSize.h" |
| #include "include/core/SkString.h" |
| #include "include/core/SkSurface.h" |
| #include "tools/timer/TimeUtils.h" |
| |
| // Mimics https://output.jsbin.com/falefice/1/quiet?CC_POSTER_CIRCLE, which can't be captured as |
| // an SKP due to many 3D layers being composited post-SKP capture. |
| // See skbug.com/9028 |
| class PosterCircleGM : public skiagm::GM { |
| public: |
| PosterCircleGM() : fTime(0.f) {} |
| |
| protected: |
| |
| SkString onShortName() override { |
| return SkString("poster_circle"); |
| } |
| |
| SkISize onISize() override { |
| return SkISize::Make(kStageWidth, kStageHeight + 50); |
| } |
| |
| bool onAnimate(double nanos) override { |
| fTime = TimeUtils::Scaled(1e-9 * nanos, 0.5f); |
| return true; |
| } |
| |
| void onOnceBeforeDraw() override { |
| SkFont font; |
| font.setEdging(SkFont::Edging::kAntiAlias); |
| font.setEmbolden(true); |
| font.setSize(24.f); |
| |
| sk_sp<SkSurface> surface = |
| SkSurfaces::Raster(SkImageInfo::MakeN32Premul(kPosterSize, kPosterSize)); |
| for (int i = 0; i < kNumAngles; ++i) { |
| SkCanvas* canvas = surface->getCanvas(); |
| |
| SkPaint fillPaint; |
| fillPaint.setAntiAlias(true); |
| fillPaint.setColor(i % 2 == 0 ? SkColorSetRGB(0x99, 0x5C, 0x7F) |
| : SkColorSetRGB(0x83, 0x5A, 0x99)); |
| canvas->drawRRect(SkRRect::MakeRectXY(SkRect::MakeWH(kPosterSize, kPosterSize), |
| 10.f, 10.f), fillPaint); |
| |
| SkString label; |
| label.printf("%d", i); |
| SkRect labelBounds; |
| font.measureText(label.c_str(), label.size(), SkTextEncoding::kUTF8, &labelBounds); |
| SkScalar labelX = 0.5f * kPosterSize - 0.5f * labelBounds.width(); |
| SkScalar labelY = 0.5f * kPosterSize + 0.5f * labelBounds.height(); |
| |
| |
| SkPaint labelPaint; |
| labelPaint.setAntiAlias(true); |
| canvas->drawString(label, labelX, labelY, font, labelPaint); |
| |
| fPosterImages[i] = surface->makeImageSnapshot(); |
| } |
| } |
| |
| void onDraw(SkCanvas* canvas) override { |
| // See https://developer.mozilla.org/en-US/docs/Web/CSS/transform-function/perspective |
| // for projection matrix when --webkit-perspective: 800px is used. |
| SkM44 proj; |
| proj.setRC(3, 2, -1.f / 800.f); |
| |
| for (int pass = 0; pass < 2; ++pass) { |
| // Want to draw 90 to 270 first (the back), then 270 to 90 (the front), but do all 3 |
| // rings backsides, then their frontsides since the front projections overlap across |
| // rings. Note: we skip the poster circle's x axis rotation because that complicates the |
| // back-to-front drawing order and it isn't necessary to trigger draws aligned with Z. |
| bool drawFront = pass > 0; |
| |
| for (int y = 0; y < 3; ++y) { |
| float ringY = (y - 1) * (kPosterSize + 10.f); |
| for (int i = 0; i < kNumAngles; ++i) { |
| // Add an extra 45 degree rotation, which triggers the bug by aligning some of |
| // the posters with the z axis. |
| SkScalar yDuration = 5.f - y; |
| SkScalar yRotation = SkScalarMod(kAngleStep * i + |
| 360.f * SkScalarMod(fTime / yDuration, yDuration), 360.f); |
| // These rotation limits were chosen manually to line up with current projection |
| static constexpr SkScalar kBackMinAngle = 70.f; |
| static constexpr SkScalar kBackMaxAngle = 290.f; |
| if (drawFront) { |
| if (yRotation >= kBackMinAngle && yRotation <= kBackMaxAngle) { |
| // Back portion during a front draw |
| continue; |
| } |
| } else { |
| if (yRotation < kBackMinAngle || yRotation > kBackMaxAngle) { |
| // Front portion during a back draw |
| continue; |
| } |
| } |
| |
| canvas->save(); |
| |
| // Matrix matches transform: rotateY(<angle>deg) translateZ(200px); nested in an |
| // element with the perspective projection matrix above. |
| SkM44 model = SkM44::Translate(kStageWidth/2, kStageHeight/2 + 25, 0) |
| * proj |
| * SkM44::Translate(0, ringY, 0) |
| * SkM44::Rotate({0,1,0}, SkDegreesToRadians(yRotation)) |
| * SkM44::Translate(0, 0, kRingRadius); |
| canvas->concat(model); |
| |
| SkRect poster = SkRect::MakeLTRB(-0.5f * kPosterSize, -0.5f * kPosterSize, |
| 0.5f * kPosterSize, 0.5f * kPosterSize); |
| SkPaint fillPaint; |
| fillPaint.setAntiAlias(true); |
| fillPaint.setAlphaf(0.7f); |
| canvas->drawImageRect(fPosterImages[i], poster, |
| SkSamplingOptions(SkFilterMode::kLinear), &fillPaint); |
| |
| canvas->restore(); |
| } |
| } |
| } |
| } |
| |
| private: |
| static const int kAngleStep = 30; |
| static const int kNumAngles = 12; // 0 through 330 degrees |
| |
| static const int kStageWidth = 600; |
| static const int kStageHeight = 400; |
| static const int kRingRadius = 200; |
| static const int kPosterSize = 100; |
| |
| sk_sp<SkImage> fPosterImages[kNumAngles]; |
| SkScalar fTime; |
| }; |
| |
| DEF_GM(return new PosterCircleGM();) |