skia2/gm/circles.cpp

/*
 * Copyright 2012 Intel Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "gm/gm.h"
#include "include/core/SkBlurTypes.h"
#include "include/core/SkCanvas.h"
#include "include/core/SkColor.h"
#include "include/core/SkDrawLooper.h"
#include "include/core/SkMaskFilter.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPoint.h"
#include "include/core/SkScalar.h"
#include "include/core/SkShader.h"
#include "include/core/SkSize.h"
#include "include/core/SkString.h"
#include "include/core/SkTileMode.h"
#include "include/core/SkTypes.h"
#include "include/effects/SkBlurDrawLooper.h"
#include "include/effects/SkGradientShader.h"
#include "include/private/SkTArray.h"
#include "include/utils/SkRandom.h"
#include "src/core/SkBlurMask.h"

namespace skiagm {

class CircleGM : public GM {
    sk_sp<SkDrawLooper> fLooper;
    enum {
        kLooperColorSentinel = 0x01020304
    };

protected:
    void onOnceBeforeDraw() override {
        this->setBGColor(0xFF000000);
        this->makePaints();
        this->makeMatrices();
    }

    SkString onShortName() override {
        return SkString("circles");
    }

    SkISize onISize() override {
        return SkISize::Make(1200, 900);
    }

    void makePaints() {
        {
        // no AA
        SkPaint p;
        fPaints.push_back(p);
        }

        {
        // AA
        SkPaint p;
        p.setAntiAlias(true);
        fPaints.push_back(p);
        }

        {
        // AA with mask filter
        SkPaint p;
        p.setAntiAlias(true);
        p.setMaskFilter(SkMaskFilter::MakeBlur(
                               kNormal_SkBlurStyle,
                               SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(5))));
        fPaints.push_back(p);
        }

        {
        // AA with radial shader
        SkPaint p;
        p.setAntiAlias(true);
        SkPoint center = SkPoint::Make(SkIntToScalar(40), SkIntToScalar(40));
        SkColor colors[] = { SK_ColorBLUE, SK_ColorRED, SK_ColorGREEN };
        SkScalar pos[] = { 0, SK_ScalarHalf, SK_Scalar1 };
        p.setShader(SkGradientShader::MakeRadial(center, 20, colors, pos, SK_ARRAY_COUNT(colors),
                                                 SkTileMode::kClamp));
        fPaints.push_back(p);
        }

        fLooper = SkBlurDrawLooper::Make(SK_ColorBLUE, SkBlurMask::ConvertRadiusToSigma(10),5,10);
        {
            SkPaint p;
            p.setColor(kLooperColorSentinel);
            p.setAntiAlias(true);
            fPaints.push_back(p);
        }
        {
        // AA with stroke style
        SkPaint p;
        p.setAntiAlias(true);
        p.setStroke(true);
        p.setStrokeWidth(SkIntToScalar(3));
        fPaints.push_back(p);
        }

        {
        // AA with stroke style, width = 0
        SkPaint p;
        p.setAntiAlias(true);
        p.setStroke(true);
        fPaints.push_back(p);
        }

        {
        // AA with stroke and fill style
        SkPaint p;
        p.setAntiAlias(true);
        p.setStyle(SkPaint::kStrokeAndFill_Style);
        p.setStrokeWidth(SkIntToScalar(2));
        fPaints.push_back(p);
        }
    }

    void makeMatrices() {
        {
        SkMatrix m;
        m.setScale(SkIntToScalar(2), SkIntToScalar(3));
        fMatrices.push_back(m);
        }

        {
        SkMatrix m;
        m.setScale(SkIntToScalar(2), SkIntToScalar(2));
        fMatrices.push_back(m);
        }

        {
        SkMatrix m;
        m.setSkew(SkIntToScalar(2), SkIntToScalar(3));
        fMatrices.push_back(m);
        }

        {
        SkMatrix m;
        m.setSkew(SkIntToScalar(2), SkIntToScalar(2));
        fMatrices.push_back(m);
        }

        {
        SkMatrix m;
        m.setRotate(SkIntToScalar(30));
        fMatrices.push_back(m);
        }
    }

    void onDraw(SkCanvas* canvas) override {
        // Draw a giant AA circle as the background.
        SkISize size = this->getISize();
        SkScalar giantRadius = std::min(SkIntToScalar(size.fWidth),
                                      SkIntToScalar(size.fHeight)) / 2.f;
        SkPoint giantCenter = SkPoint::Make(SkIntToScalar(size.fWidth/2),
                                            SkIntToScalar(size.fHeight/2));
        SkPaint giantPaint;
        giantPaint.setAntiAlias(true);
        giantPaint.setColor(0x80808080);
        canvas->drawCircle(giantCenter, giantRadius, giantPaint);

        SkRandom rand;
        canvas->translate(20 * SK_Scalar1, 20 * SK_Scalar1);
        int i;
        for (i = 0; i < fPaints.count(); ++i) {
            canvas->save();
            // position the path, and make it at off-integer coords.
            canvas->translate(SK_Scalar1 * 200 * (i % 5) + SK_Scalar1 / 4,
                              SK_Scalar1 * 200 * (i / 5) + 3 * SK_Scalar1 / 4);
            SkPaint p = fPaints[i];
            p.setColor(rand.nextU() | 0xff000000);
            if (fPaints[i].getColor() == kLooperColorSentinel) {
                fLooper->apply(canvas, p, [](SkCanvas* c, const SkPaint& p) {
                    c->drawCircle(40, 40, 20, p);
                });
            } else {
                canvas->drawCircle(40, 40, 20, p);
            }
            canvas->restore();
        }

        for (int j = 0; j < fMatrices.count(); ++j, ++i) {
            canvas->save();

            canvas->translate(SK_Scalar1 * 200 * (i % 5) + SK_Scalar1 / 4,
                              SK_Scalar1 * 200 * (i / 5) + 3 * SK_Scalar1 / 4);

            canvas->concat(fMatrices[j]);

            SkPaint paint;
            paint.setAntiAlias(true);
            paint.setColor(rand.nextU() | 0xff000000);
            canvas->drawCircle(40, 40, 20, paint);

            canvas->restore();
        }
    }

private:
    using INHERITED = GM;
    SkTArray<SkPaint> fPaints;
    SkTArray<SkMatrix> fMatrices;
};

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

DEF_GM( return new CircleGM; )

}  // namespace skiagm