gm/imagefiltersbase.cpp

/*
 * Copyright 2011 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "gm.h"
#include "SkCanvas.h"
#include "SkColorFilter.h"
#include "SkColorPriv.h"
#include "SkShader.h"

#include "SkBlurImageFilter.h"
#include "SkTestImageFilters.h"

class FailImageFilter : public SkImageFilter {
public:
    FailImageFilter() {}
    virtual Factory getFactory() SK_OVERRIDE { return CreateProc; };
    
protected:
    virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
                               SkBitmap* result, SkIPoint* offset) {
        return false;
    }
    
    FailImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}

private:
    static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
        return new FailImageFilter(buffer);
    }
    
    typedef SkImageFilter INHERITED;
};

class IdentityImageFilter : public SkImageFilter {
public:
    IdentityImageFilter() {}
    virtual Factory getFactory() SK_OVERRIDE { return CreateProc; };

protected:
    virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&,
                               SkBitmap* result, SkIPoint* offset) {
        *result = src;
        return true;
    }

    IdentityImageFilter(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}

private:
    static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
        return new IdentityImageFilter(buffer);
    }
    
    typedef SkImageFilter INHERITED;
};

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

static void draw_paint(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
    SkPaint paint;
    paint.setImageFilter(imf);
    paint.setColor(SK_ColorGREEN);
    canvas->save();
    canvas->clipRect(r);
    canvas->drawPaint(paint);
    canvas->restore();
}

static void draw_line(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
    SkPaint paint;
    paint.setColor(SK_ColorBLUE);
    paint.setImageFilter(imf);
    paint.setStrokeWidth(r.width()/10);
    canvas->drawLine(r.fLeft, r.fTop, r.fRight, r.fBottom, paint);
}

static void draw_rect(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
    SkPaint paint;
    paint.setColor(SK_ColorYELLOW);
    paint.setImageFilter(imf);
    SkRect rr(r);
    rr.inset(r.width()/10, r.height()/10);
    canvas->drawRect(rr, paint);
}

static void draw_path(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
    SkPaint paint;
    paint.setColor(SK_ColorMAGENTA);
    paint.setImageFilter(imf);
    paint.setAntiAlias(true);
    canvas->drawCircle(r.centerX(), r.centerY(), r.width()*2/5, paint);
}

static void draw_text(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
    SkPaint paint;
    paint.setImageFilter(imf);
    paint.setColor(SK_ColorCYAN);
    paint.setAntiAlias(true);
    paint.setTextSize(r.height()/2);
    paint.setTextAlign(SkPaint::kCenter_Align);
    canvas->drawText("Text", 4, r.centerX(), r.centerY(), paint);
}

static void draw_bitmap(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
    SkPaint paint;
    paint.setImageFilter(imf);
    
    SkIRect bounds;
    r.roundOut(&bounds);
    
    SkBitmap bm;
    bm.setConfig(SkBitmap::kARGB_8888_Config, bounds.width(), bounds.height());
    bm.allocPixels();
    bm.eraseColor(0);
    SkCanvas c(bm);
    draw_path(&c, r, NULL);
    
    canvas->drawBitmap(bm, 0, 0, &paint);
}

static void draw_sprite(SkCanvas* canvas, const SkRect& r, SkImageFilter* imf) {
    SkPaint paint;
    paint.setImageFilter(imf);
    
    SkIRect bounds;
    r.roundOut(&bounds);
    
    SkBitmap bm;
    bm.setConfig(SkBitmap::kARGB_8888_Config, bounds.width(), bounds.height());
    bm.allocPixels();
    bm.eraseColor(0);
    SkCanvas c(bm);
    draw_path(&c, r, NULL);

    SkPoint loc = { r.fLeft, r.fTop };
    canvas->getTotalMatrix().mapPoints(&loc, 1);
    canvas->drawSprite(bm,
                       SkScalarRoundToInt(loc.fX), SkScalarRoundToInt(loc.fY),
                       &paint);
}

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

class ImageFiltersBaseGM : public skiagm::GM {
public:
    ImageFiltersBaseGM () {}

protected:

    virtual SkString onShortName() {
        return SkString("imagefiltersbase");
    }

    virtual SkISize onISize() { return SkISize::Make(700, 460); }

    void draw_frame(SkCanvas* canvas, const SkRect& r) {
        SkPaint paint;
        paint.setStyle(SkPaint::kStroke_Style);
        paint.setColor(SK_ColorRED);
        canvas->drawRect(r, paint);
    }

    virtual void onDraw(SkCanvas* canvas) {
        void (*drawProc[])(SkCanvas*, const SkRect&, SkImageFilter*) = {
            draw_paint,
            draw_line, draw_rect, draw_path, draw_text,
            draw_bitmap,
            draw_sprite
        };
        
        SkColorFilter* cf = SkColorFilter::CreateModeFilter(SK_ColorRED,
                                                     SkXfermode::kSrcIn_Mode);
        SkImageFilter* filters[] = {
#if 1
            NULL,
            new IdentityImageFilter,
            new FailImageFilter,
            new SkColorFilterImageFilter(cf),
#endif
            new SkBlurImageFilter(12.0f, 0.0f),
        };
        cf->unref();

        SkRect r = SkRect::MakeWH(SkIntToScalar(64), SkIntToScalar(64));
        SkScalar MARGIN = SkIntToScalar(16);
        SkScalar DX = r.width() + MARGIN;
        SkScalar DY = r.height() + MARGIN;

        canvas->translate(MARGIN, MARGIN);
        for (size_t i = 0; i < SK_ARRAY_COUNT(drawProc); ++i) {
            canvas->save();
            for (size_t j = 0; j < SK_ARRAY_COUNT(filters); ++j) {
                drawProc[i](canvas, r, filters[j]);
                
                draw_frame(canvas, r);
                canvas->translate(0, DY);
            }
            canvas->restore();
            canvas->translate(DX, 0);
        }
    }

private:
    typedef GM INHERITED;
};

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

static skiagm::GM* MyFactory(void*) { return new ImageFiltersBaseGM; }
static skiagm::GMRegistry reg(MyFactory);