skia2/gm/offsetimagefilter.cpp

/*
 * Copyright 2013 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "sk_tool_utils.h"
#include "SkImage.h"
#include "SkImageSource.h"
#include "SkOffsetImageFilter.h"
#include "SkSurface.h"
#include "gm.h"

#define WIDTH 600
#define HEIGHT 100
#define MARGIN 12

class OffsetImageFilterGM : public skiagm::GM {
public:
    OffsetImageFilterGM() {
        this->setBGColor(0xFF000000);
    }

protected:
    SkString onShortName() override {
        return SkString("offsetimagefilter");
    }

    SkISize onISize() override {
        return SkISize::Make(WIDTH, HEIGHT);
    }

    void onOnceBeforeDraw() override {
        fBitmap.reset(SkImage::NewFromBitmap(
            sk_tool_utils::create_string_bitmap(80, 80, 0xD000D000, 15, 65, 96, "e")));
        
        fCheckerboard.reset(SkImage::NewFromBitmap(
            sk_tool_utils::create_checkerboard_bitmap(80, 80,
                                                      sk_tool_utils::color_to_565(0xFFA0A0A0),
                                                      sk_tool_utils::color_to_565(0xFF404040),
                                                      8)));
    }

    void onDraw(SkCanvas* canvas) override {
        canvas->clear(SK_ColorBLACK);
        SkPaint paint;

        for (int i = 0; i < 4; i++) {
            const SkImage* image = (i & 0x01) ? fCheckerboard : fBitmap;
            SkIRect cropRect = SkIRect::MakeXYWH(i * 12,
                                                 i * 8,
                                                 image->width() - i * 8,
                                                 image->height() - i * 12);
            SkImageFilter::CropRect rect(SkRect::Make(cropRect));
            SkAutoTUnref<SkImageFilter> tileInput(SkImageSource::Create(image));
            SkScalar dx = SkIntToScalar(i*5);
            SkScalar dy = SkIntToScalar(i*10);
            SkAutoTUnref<SkImageFilter> filter(SkOffsetImageFilter::Create(dx, dy, tileInput,
                                                                           &rect));
            paint.setImageFilter(filter);
            DrawClippedImage(canvas, image, paint, 1, cropRect);
            canvas->translate(SkIntToScalar(image->width() + MARGIN), 0);
        }

        SkIRect cropRect = SkIRect::MakeXYWH(0, 0, 100, 100);
        SkImageFilter::CropRect rect(SkRect::Make(cropRect));
        SkAutoTUnref<SkImageFilter> filter(SkOffsetImageFilter::Create(-5, -10, nullptr, &rect));
        paint.setImageFilter(filter);
        DrawClippedImage(canvas, fBitmap, paint, 2, cropRect);
    }
private:
    static void DrawClippedImage(SkCanvas* canvas, const SkImage* image, const SkPaint& paint,
                          SkScalar scale, const SkIRect& cropRect) {
        SkRect clipRect = SkRect::MakeIWH(image->width(), image->height());

        canvas->save();
        canvas->clipRect(clipRect);
        canvas->scale(scale, scale);
        canvas->drawImage(image, 0, 0, &paint);
        canvas->restore();

        // Draw a boundary rect around the intersection of the clip rect and crop rect.
        SkRect cropRectFloat;
        SkMatrix::MakeScale(scale, scale).mapRect(&cropRectFloat, SkRect::Make(cropRect));
        if (clipRect.intersect(cropRectFloat)) {
            SkPaint strokePaint;
            strokePaint.setStyle(SkPaint::kStroke_Style);
            strokePaint.setStrokeWidth(2);
            strokePaint.setColor(SK_ColorRED);
            canvas->drawRect(clipRect, strokePaint);
        }
    }

    SkAutoTUnref<SkImage> fBitmap, fCheckerboard;

    typedef skiagm::GM INHERITED;
};
DEF_GM( return new OffsetImageFilterGM; )

//////////////////////////////////////////////////////////////////////////////

class SimpleOffsetImageFilterGM : public skiagm::GM {
public:
    SimpleOffsetImageFilterGM() {}
    
protected:
    SkString onShortName() override {
        return SkString("simple-offsetimagefilter");
    }
    
    SkISize onISize() override { return SkISize::Make(640, 200); }
    
    void doDraw(SkCanvas* canvas, const SkRect& r, SkImageFilter* imgf,
                const SkRect* clipR = nullptr) {
        SkPaint p;

        if (clipR) {
            p.setColor(0xFF00FF00);
            p.setStyle(SkPaint::kStroke_Style);
            canvas->drawRect(clipR->makeInset(SK_ScalarHalf, SK_ScalarHalf), p);
            p.setStyle(SkPaint::kFill_Style);
        }

        if (imgf && imgf->cropRectIsSet()) {
            SkImageFilter::CropRect cr = imgf->getCropRect();

            p.setColor(0x66FF00FF);
            p.setStyle(SkPaint::kStroke_Style);
            canvas->drawRect(cr.rect().makeInset(SK_ScalarHalf, SK_ScalarHalf), p);
            p.setStyle(SkPaint::kFill_Style);
        }

        p.setColor(0x660000FF);
        canvas->drawRect(r, p);

        if (clipR) {
            canvas->save();
            canvas->clipRect(*clipR);
        }
        if (imgf) {
            p.setImageFilter(imgf)->unref();
        }
        p.setColor(0x66FF0000);
        canvas->drawRect(r, p);

        if (clipR) {
            canvas->restore();
        }
    }

    void onDraw(SkCanvas* canvas) override {
        const SkRect r = SkRect::MakeWH(40, 40);
        SkImageFilter::CropRect cr0(r);
        SkImageFilter::CropRect cr1(SkRect::MakeWH(20, 20));
        const SkRect r2 = SkRect::MakeXYWH(40, 0, 40, 40);
        SkImageFilter::CropRect cr2(r2);

        canvas->translate(40, 40);
        
        canvas->save();
        this->doDraw(canvas, r, nullptr);
        
        canvas->translate(100, 0);
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(20, 20));
        
        canvas->translate(100, 0);
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(20, 20, nullptr, &cr0));
        
        canvas->translate(100, 0);
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(20, 20), &r);
        
        canvas->translate(100, 0);
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(20, 20, nullptr, &cr1));
        
        SkRect clipR = SkRect::MakeXYWH(40, 40, 40, 40);
        canvas->translate(100, 0);
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(20, 20, nullptr, nullptr), &clipR);
        canvas->restore();

        // 2nd row
        canvas->translate(0, 80);

        /*
         *  combos of clip and crop rects that align with src and dst
         */

        // crop==clip==src
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(40, 0, nullptr, &cr0), &r);

        // crop==src, clip==dst
        canvas->translate(100, 0);
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(40, 0, nullptr, &cr0), &r2);

        // crop==dst, clip==src
        canvas->translate(100, 0);
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(40, 0, nullptr, &cr2), &r);

        // crop==clip==dst
        canvas->translate(100, 0);
        this->doDraw(canvas, r, SkOffsetImageFilter::Create(40, 0, nullptr, &cr2), &r2);
    }

private:
    typedef skiagm::GM INHERITED;
};
DEF_GM( return new SimpleOffsetImageFilterGM; )