void onDrawContent(SkCanvas* canvas) override {
        SkPaint paint;
        SkSafeUnref(paint.setTypeface(SkTypeface::CreateFromFile("/skimages/samplefont.ttf")));
        paint.setAntiAlias(true);
        paint.setFilterQuality(kMedium_SkFilterQuality);

        SkString outString("fps: ");
        fTimer.end();

        // TODO: generalize this timing code in utils
        fTimes[fCurrentTime] = (float)(fTimer.fWall);
        fCurrentTime = (fCurrentTime + 1) & 0x1f;

        float meanTime = 0.0f;
        for (int i = 0; i < 32; ++i) {
            meanTime += fTimes[i];
        }
        meanTime /= 32.f;
        SkScalar fps = 1000.f / meanTime;
        outString.appendScalar(fps);
        outString.append(" ms: ");
        outString.appendScalar(meanTime);

        SkString modeString("Text scale: ");
        modeString.appendU32(fSizeScale);
        modeString.append("x");

        fTimer.start();

        canvas->save();

#if SK_SUPPORT_GPU
        SkBaseDevice* device = canvas->getDevice_just_for_deprecated_compatibility_testing();
        GrContext* grContext = canvas->getGrContext();
        if (grContext) {
            GrTexture* tex = grContext->getFontAtlasTexture(GrMaskFormat::kA8_GrMaskFormat);
            reinterpret_cast<SkGpuDevice*>(device)->drawTexture(tex,
                                                       SkRect::MakeXYWH(512, 10, 512, 512), paint);
        }
#endif
        canvas->translate(180, 180);
        canvas->rotate(fRotation);
        canvas->scale(fScale, fScale);
        canvas->translate(-180, -180);

        const char* text = "Hamburgefons";
        size_t length = strlen(text);

        SkScalar y = SkIntToScalar(0);
        for (int i = 12; i <= 26; i++) {
            paint.setTextSize(SkIntToScalar(i*fSizeScale));
            y += paint.getFontSpacing();
            DrawTheText(canvas, text, length, SkIntToScalar(110), y, paint);
        }
        canvas->restore();

        paint.setTextSize(16);
//        canvas->drawText(outString.c_str(), outString.size(), 512.f, 540.f, paint);
        canvas->drawText(modeString.c_str(), modeString.size(), 768.f, 540.f, paint);
    }