text: /*
   * Copyright 2015 Google Inc.
   *
   * Use of this source code is governed by a BSD-style license that can be
   * found in the LICENSE file.
   */
  
  #include "bench/SKPAnimationBench.h"
  #include "include/core/SkSurface.h"
  #include "tools/flags/CommandLineFlags.h"
  
  SKPAnimationBench::SKPAnimationBench(const char* name, const SkPicture* pic, const SkIRect& clip,
                                       sk_sp<Animation> animation, bool doLooping)
      : INHERITED(name, pic, clip, 1.0, doLooping)
      , fAnimation(std::move(animation)) {
      fUniqueName.printf("%s_%s", name, fAnimation->getTag());
  }
  
  const char* SKPAnimationBench::onGetUniqueName() {
      return fUniqueName.c_str();
  }
  
  void SKPAnimationBench::onPerCanvasPreDraw(SkCanvas* canvas) {
      INHERITED::onPerCanvasPreDraw(canvas);
      fDevBounds = canvas->getDeviceClipBounds();
      SkAssertResult(!fDevBounds.isEmpty());
  }
  
  void SKPAnimationBench::drawPicture() {
      for (int j = 0; j < this->tileRects().count(); ++j) {
          SkMatrix trans = SkMatrix::Translate(-1.f * this->tileRects()[j].fLeft,
                                               -1.f * this->tileRects()[j].fTop);
          fAnimation->preConcatFrameMatrix(fAnimationTime.nextRangeF(0, 1000), fDevBounds, &trans);
          this->surfaces()[j]->getCanvas()->drawPicture(this->picture(), &trans, nullptr);
      }
  
      for (int j = 0; j < this->tileRects().count(); ++j) {
         this->surfaces()[j]->flush();
      }
  }
  
  class ZoomAnimation : public SKPAnimationBench::Animation {
  public:
      ZoomAnimation(SkScalar zoomMax, double zoomPeriodMs)
          : fZoomMax(zoomMax)
          , fZoomPeriodMs(zoomPeriodMs) {
      }
  
      const char* getTag() override { return "zoom"; }
  
      void preConcatFrameMatrix(double animationTimeMs, const SkIRect& devBounds,
                                SkMatrix* drawMatrix) override {
          double t = fmod(animationTimeMs / fZoomPeriodMs, 1.0); // t is in [0, 1).
          t = fabs(2 * t - 1); // Make t ping-pong between 0 and 1
          SkScalar zoom = static_cast<SkScalar>(pow(fZoomMax, t));
  
          SkPoint center = SkPoint::Make((devBounds.fLeft + devBounds.fRight) / 2.0f,
                                         (devBounds.fTop + devBounds.fBottom) / 2.0f);
          drawMatrix->preTranslate(center.fX, center.fY);
          drawMatrix->preScale(zoom, zoom);
          drawMatrix->preTranslate(-center.fX, -center.fY);
      }
  
  private:
      double   fZoomMax;
      double   fZoomPeriodMs;
  };
  
  sk_sp<SKPAnimationBench::Animation> SKPAnimationBench::MakeZoomAnimation(SkScalar zoomMax,
                                                                           double zoomPeriodMs) {
      return sk_make_sp<ZoomAnimation>(zoomMax, zoomPeriodMs);
  }
  