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      1 
      2 /*
      3  * Copyright 2012 Google Inc.
      4  *
      5  * Use of this source code is governed by a BSD-style license that can be
      6  * found in the LICENSE file.
      7  */
      8 
      9 #include "gm.h"
     10 #include "SkCanvas.h"
     11 #include "SkPath.h"
     12 #include "SkPicture.h"
     13 #include "SkPictureRecorder.h"
     14 
     15 namespace skiagm {
     16 
     17 class DistantClipGM : public GM {
     18 public:
     19     DistantClipGM() { }
     20 
     21 protected:
     22 
     23     SkString onShortName() {
     24         return SkString("distantclip");
     25     }
     26 
     27     SkISize onISize() { return SkISize::Make(100, 100); }
     28 
     29     virtual void onDraw(SkCanvas* canvas) {
     30         constexpr SkScalar kOffset = 35000.0f;
     31         constexpr SkScalar kExtents = 1000.0f;
     32 
     33         SkPictureRecorder recorder;
     34         // We record a picture of huge vertical extents in which we clear the canvas to red, create
     35         // a 'extents' by 'extents' round rect clip at a vertical offset of 'offset', then draw
     36         // green into that.
     37         SkCanvas* rec = recorder.beginRecording(kExtents, kOffset + kExtents, nullptr, 0);
     38         rec->drawColor(SK_ColorRED);
     39         rec->save();
     40         SkRect r = SkRect::MakeXYWH(-kExtents, kOffset - kExtents, 2 * kExtents, 2 * kExtents);
     41         SkPath p;
     42         p.addRoundRect(r, 5, 5);
     43         rec->clipPath(p, true);
     44         rec->drawColor(SK_ColorGREEN);
     45         rec->restore();
     46         sk_sp<SkPicture> pict(recorder.finishRecordingAsPicture());
     47 
     48         // Next we play that picture into another picture of the same size.
     49         pict->playback(recorder.beginRecording(pict->cullRect().width(),
     50                                                pict->cullRect().height(),
     51                                                nullptr, 0));
     52         sk_sp<SkPicture> pict2(recorder.finishRecordingAsPicture());
     53 
     54         // Finally we play the part of that second picture that should be green into the canvas.
     55         canvas->save();
     56         canvas->translate(kExtents / 2, -(kOffset - kExtents / 2));
     57         pict2->playback(canvas);
     58         canvas->restore();
     59 
     60         // If the image is red, we erroneously decided the clipPath was empty and didn't record
     61         // the green drawColor, if it's green we're all good.
     62     }
     63 
     64 private:
     65     typedef GM INHERITED;
     66 };
     67 
     68 ///////////////////////////////////////////////////////////////////////////////
     69 
     70 static GM* MyFactory(void*) { return new DistantClipGM; }
     71 static GMRegistry reg(MyFactory);
     72 
     73 }
     74