distantclip.cpp revision 5fb2ce38b3dcb8e60e9e112df23c9d42456d7069 
1
2
3/*
4 * Copyright 2012 Google Inc.
5 *
6 * Use of this source code is governed by a BSD-style license that can be
7 * found in the LICENSE file.
8 */
9
10#include "gm.h"
11#include "SkCanvas.h"
12#include "SkPicture.h"
13
14namespace skiagm {
15
16class DistantClipGM : public GM {
17public:
18    DistantClipGM() { }
19
20protected:
21
22    SkString onShortName() {
23        return SkString("distantclip");
24    }
25
26    SkISize onISize() { return make_isize(100, 100); }
27
28    virtual void onDraw(SkCanvas* canvas) {
29        int offset = 35000;
30        int extents = 1000;
31
32        SkPictureRecorder recorder;
33        // We record a picture of huge vertical extents in which we clear the canvas to red, create
34        // a 'extents' by 'extents' round rect clip at a vertical offset of 'offset', then draw
35        // green into that.
36        SkCanvas* rec = recorder.beginRecording(100, offset + extents, NULL, 0);
37        rec->drawColor(0xffff0000);
38        rec->save();
39        SkRect r = {
40            SkIntToScalar(-extents),
41            SkIntToScalar(offset - extents),
42            SkIntToScalar(extents),
43            SkIntToScalar(offset + extents)
44        };
45        SkPath p;
46        p.addRoundRect(r, 5, 5);
47        rec->clipPath(p, SkRegion::kIntersect_Op, true);
48        rec->drawColor(0xff00ff00);
49        rec->restore();
50        SkAutoTUnref<SkPicture> pict(recorder.endRecording());
51
52        // Next we play that picture into another picture of the same size.
53        pict->draw(recorder.beginRecording(100, offset + extents, NULL, 0));
54        SkAutoTUnref<SkPicture> pict2(recorder.endRecording());
55
56        // Finally we play the part of that second picture that should be green into the canvas.
57        canvas->save();
58        canvas->translate(SkIntToScalar(extents / 2),
59                          SkIntToScalar(-(offset - extents / 2)));
60        pict2->draw(canvas);
61        canvas->restore();
62
63        // If the image is red, we erroneously decided the clipPath was empty and didn't record
64        // the green drawColor, if it's green we're all good.
65    }
66
67private:
68    typedef GM INHERITED;
69};
70
71///////////////////////////////////////////////////////////////////////////////
72
73static GM* MyFactory(void*) { return new DistantClipGM; }
74static GMRegistry reg(MyFactory);
75
76}
77