C++ SkRandom::nextUScalar1方法代码示例

static void show_stroke(SkCanvas* canvas, bool doAA, SkScalar strokeWidth, int n) {
    SkRandom rand;
    SkPaint paint;
    paint.setAntiAlias(doAA);
    paint.setStyle(SkPaint::kStroke_Style);
    paint.setStrokeWidth(strokeWidth);
    
    for (int i = 0; i < n; ++i) {
        SkRect r;
        SkPath p;
        
        r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
                  rand.nextUScalar1() * W, rand.nextUScalar1() * H);
        paint.setColor(rand.nextU());
        canvas->drawRect(r, paint);
        
        r.setXYWH(rand.nextSScalar1() * W, rand.nextSScalar1() * H,
                  rand.nextUScalar1() * W, rand.nextUScalar1() * H);
        paint.setColor(rand.nextU());
        p.addOval(r);
        canvas->drawPath(p, paint);

        const SkScalar minx = -SkIntToScalar(W)/4;
        const SkScalar maxx = 5*SkIntToScalar(W)/4;
        const SkScalar miny = -SkIntToScalar(H)/4;
        const SkScalar maxy = 5*SkIntToScalar(H)/4;
        paint.setColor(rand.nextU());
        canvas->drawLine(randRange(rand, minx, maxx), randRange(rand, miny, maxy),
                         randRange(rand, minx, maxx), randRange(rand, miny, maxy),
                         paint);
    }
}

    virtual void onDraw(int loops, SkCanvas* canvas) {
        const SkIPoint dim = this->getSize();
        SkRandom rand;

        SkPaint paint(fPaint);
        this->setupPaint(&paint);
        // explicitly need these
        paint.setAlpha(fPaint.getAlpha());
        paint.setAntiAlias(kBW != fFQ);
        paint.setLCDRenderText(kLCD == fFQ);

        const SkScalar x0 = SkIntToScalar(-10);
        const SkScalar y0 = SkIntToScalar(-10);

        paint.setTextSize(SkIntToScalar(12));
        for (int i = 0; i < loops; i++) {
            SkScalar x = x0 + rand.nextUScalar1() * dim.fX;
            SkScalar y = y0 + rand.nextUScalar1() * dim.fY;
            canvas->drawString(fText, x, y, paint);
        }

        paint.setTextSize(SkIntToScalar(48));
        for (int i = 0; i < loops / 4 ; i++) {
            SkScalar x = x0 + rand.nextUScalar1() * dim.fX;
            SkScalar y = y0 + rand.nextUScalar1() * dim.fY;
            canvas->drawString(fText, x, y, paint);
        }
    }

    LineBench(SkScalar width, bool doAA)  {
        fStrokeWidth = width;
        fDoAA = doAA;
        fName.printf("lines_%g_%s", width, doAA ? "AA" : "BW");

        SkRandom rand;
        for (int i = 0; i < PTS; ++i) {
            fPts[i].set(rand.nextUScalar1() * 640, rand.nextUScalar1() * 480);
        }
    }

static void make_tris(Rec* rec) {
    int n = 10;
    SkRandom    rand;

    rec->fMode = SkCanvas::kTriangles_VertexMode;
    rec->fCount = n * 3;
    rec->fVerts = new SkPoint[rec->fCount];

    for (int i = 0; i < n; i++) {
        SkPoint* v = &rec->fVerts[i*3];
        for (int j = 0; j < 3; j++) {
            v[j].set(rand.nextUScalar1() * 250, rand.nextUScalar1() * 250);
        }
    }
}

 void randPts() {
     for (size_t i = 0; i < SK_ARRAY_COUNT(fPts); i++) {
         fPts[i].set(fRand.nextUScalar1() * 640,
                     fRand.nextUScalar1() * 480);
     }
     fCounter += 1;
 }

 void onDelayedSetup() override {
     if (!fInit) {
         SkRandom rand;
         static const SkScalar kMinOffset = 0;
         static const SkScalar kMaxOffset = 100 * SK_Scalar1;
         static const SkScalar kOffsetRange = kMaxOffset - kMinOffset;
         for (int i = 0; i < N; ++i) {
             fRects[i].fLeft = -kMinOffset - SkScalarMul(rand.nextUScalar1(), kOffsetRange);
             fRects[i].fTop = -kMinOffset - SkScalarMul(rand.nextUScalar1(), kOffsetRange);
             fRects[i].fRight = W + kMinOffset + SkScalarMul(rand.nextUScalar1(), kOffsetRange);
             fRects[i].fBottom = H + kMinOffset + SkScalarMul(rand.nextUScalar1(), kOffsetRange);
             fColors[i] = rand.nextU() | 0xFF000000;
         }
         fInit = true;
     }
 }

    virtual void onDraw(SkCanvas* canvas) {
        const SkIPoint dim = this->getSize();
        SkRandom rand;

        SkPaint paint(fPaint);
        this->setupPaint(&paint);
        // explicitly need these
        paint.setColor(fPaint.getColor());
        paint.setAntiAlias(kBW != fFQ);
        paint.setLCDRenderText(kLCD == fFQ);

        const SkScalar x0 = SkIntToScalar(-10);
        const SkScalar y0 = SkIntToScalar(-10);

        if (fDoPos) {
            // realistically, the matrix is often at least translated, so we
            // do that since it exercises different code in drawPosText.
            canvas->translate(SK_Scalar1, SK_Scalar1);
        }

        for (int i = 0; i < N; i++) {
            if (fDoPos) {
                canvas->drawPosText(fText.c_str(), fText.size(), fPos, paint);
            } else {
                SkScalar x = x0 + rand.nextUScalar1() * dim.fX;
                SkScalar y = y0 + rand.nextUScalar1() * dim.fY;
                canvas->drawText(fText.c_str(), fText.size(), x, y, paint);
            }
        }
    }

    void onDraw(SkCanvas* canvas) override {
        canvas->translate(20, 20);

        SkRect r = SkRect::MakeWH(1000, 1000);

        SkPaint paint;
        paint.setAntiAlias(true);
        paint.setStyle(SkPaint::kStroke_Style);
        paint.setStrokeWidth(15);

        const SkScalar inset = paint.getStrokeWidth() + 4;
        const SkScalar sweepAngle = 345;
        SkRandom rand;

        SkScalar sign = 1;
        while (r.width() > paint.getStrokeWidth() * 3) {
            paint.setColor(sk_tool_utils::color_to_565(rand.nextU() | (0xFF << 24)));
            SkScalar startAngle = rand.nextUScalar1() * 360;

            SkScalar speed = SkScalarSqrt(16 / r.width()) * 0.5f;
            startAngle += fRotate * 360 * speed * sign;

            SkPath path;
            path.addArc(r, startAngle, sweepAngle);
            canvas->drawPath(path, paint);

            r.inset(inset, inset);
            sign = -sign;
        }
    }

    virtual void onDraw(SkCanvas* canvas) {
        SkPaint paint;
        this->setupPaint(&paint);

        paint.setAntiAlias(true);

        SkRandom rand;
        for (int i = 0; i < SkBENCHLOOP(3); i++) {
            SkRect r = SkRect::MakeWH(rand.nextUScalar1() * 400,
                                      rand.nextUScalar1() * 400);
            r.offset(fRadius, fRadius);

            if (fRadius > 0) {
                SkMorphologyImageFilter* mf = NULL;
                switch (fStyle) {
                case kDilate_MT:
                    mf = new SkDilateImageFilter(SkScalarFloorToInt(fRadius),
                                                 SkScalarFloorToInt(fRadius));
                    break;
                case kErode_MT:
                    mf = new SkErodeImageFilter(SkScalarFloorToInt(fRadius),
                                                SkScalarFloorToInt(fRadius));
                    break;
                }
                paint.setImageFilter(mf)->unref();
            }
            canvas->drawOval(r, paint);
        }
    }

    void onDrawContent(SkCanvas* canvas) override {
        test_huge_stroke(canvas); return;
        canvas->translate(SkIntToScalar(10), SkIntToScalar(10));

        SkPaint paint;
        paint.setAntiAlias(true);

        if (true) {
            canvas->drawColor(SK_ColorBLACK);

            paint.setTextSize(24);
            paint.setColor(SK_ColorWHITE);
            canvas->translate(10, 30);

            static const SkBlurStyle gStyle[] = {
                kNormal_SkBlurStyle,
                kInner_SkBlurStyle,
                kOuter_SkBlurStyle,
                kSolid_SkBlurStyle,
            };
            for (int x = 0; x < 5; x++) {
                SkScalar sigma = SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(4));
                for (int y = 0; y < 10; y++) {
                    if (x) {
                        paint.setMaskFilter(SkBlurMaskFilter::Make(gStyle[x - 1], sigma));
                    }
                    canvas->drawString("Title Bar", x*SkIntToScalar(100), y*SkIntToScalar(30), paint);
                    sigma *= 0.75f;
                }

            }
            return;
        }

        paint.setColor(SK_ColorBLUE);

#if 1
        SkPath p;
        float r = rand.nextUScalar1() + 0.5f;
        SkScalar x = 0, y = 0;
        p.moveTo(x, y);
#if 0
        p.cubicTo(x-75*r, y+75*r, x-40*r, y+125*r, x, y+85*r);
        p.cubicTo(x+40*r, y+125*r, x+75*r, y+75*r, x, y);
#else
        p.cubicTo(x+75*r, y+75*r, x+40*r, y+125*r, x, y+85*r);
        p.cubicTo(x-40*r, y+125*r, x-75*r, y+75*r, x, y);
#endif
        p.close();
        fPath = p;
        fPath.offset(100, 0);
#endif

        fPath.setFillType(SkPath::kWinding_FillType);
        drawSet(canvas, &paint);

        canvas->translate(0, fPath.getBounds().height() * 5 / 4);
        fPath.setFillType(SkPath::kEvenOdd_FillType);
        drawSet(canvas, &paint);
    }

 void onDraw(const int loops, SkCanvas* canvas) override {
     const char* text = "Hamburgefons";
     size_t len = strlen(text);
     SkISize size = canvas->getDeviceSize();
     SkRandom random;
     for (int i = 0; i < loops; ++i) {
         SkPaint paint;
         paint.setXfermode(fXfermode.get());
         paint.setColor(random.nextU());
         if (fAA) {
             // Draw text to exercise AA code paths.
             paint.setAntiAlias(true);
             paint.setTextSize(random.nextRangeScalar(12, 96));
             SkScalar x = random.nextRangeScalar(0, (SkScalar)size.fWidth),
                      y = random.nextRangeScalar(0, (SkScalar)size.fHeight);
             for (int j = 0; j < 1000; ++j) {
                 canvas->drawText(text, len, x, y, paint);
             }
         } else {
             // Draw rects to exercise non-AA code paths.
             SkScalar w = random.nextRangeScalar(50, 100);
             SkScalar h = random.nextRangeScalar(50, 100);
             SkRect rect = SkRect::MakeXYWH(
                 random.nextUScalar1() * (size.fWidth - w),
                 random.nextUScalar1() * (size.fHeight - h),
                 w,
                 h
             );
             for (int j = 0; j < 1000; ++j) {
                 canvas->drawRect(rect, paint);
             }
         }
     }
 }

    void onDraw(int loops, SkCanvas* canvas) override {
        SkPaint paint;
        this->setupPaint(&paint);

        paint.setAntiAlias(true);

        SkRandom rand;
        for (int i = 0; i < loops; i++) {
            SkRect r = SkRect::MakeWH(rand.nextUScalar1() * 400,
                                      rand.nextUScalar1() * 400);
            r.offset(fRadius, fRadius);

            if (fRadius > 0) {
                sk_sp<SkImageFilter> mf;
                switch (fStyle) {
                case kDilate_MT:
                    mf = SkDilateImageFilter::Make(SkScalarFloorToInt(fRadius),
                                                   SkScalarFloorToInt(fRadius),
                                                   nullptr);
                    break;
                case kErode_MT:
                    mf = SkErodeImageFilter::Make(SkScalarFloorToInt(fRadius),
                                                  SkScalarFloorToInt(fRadius),
                                                  nullptr);
                    break;
                }
                paint.setImageFilter(std::move(mf));
            }
            canvas->drawOval(r, paint);
        }
    }

    DrawAtlasDrawable(DrawAtlasProc proc, const SkRect& r)
        : fProc(proc), fBounds(r), fUseColors(false)
    {
        SkRandom rand;
        fAtlas = make_atlas(kAtlasSize, kCellSize);
        const SkScalar kMaxSpeed = 5;
        const SkScalar cell = SkIntToScalar(kCellSize);
        int i = 0;
        for (int y = 0; y < kAtlasSize; y += kCellSize) {
            for (int x = 0; x < kAtlasSize; x += kCellSize) {
                const SkScalar sx = SkIntToScalar(x);
                const SkScalar sy = SkIntToScalar(y);
                fTex[i].setXYWH(sx, sy, cell, cell);

                fRec[i].fCenter.set(sx + cell/2, sy + 3*cell/4);
                fRec[i].fVelocity.fX = rand.nextSScalar1() * kMaxSpeed;
                fRec[i].fVelocity.fY = rand.nextSScalar1() * kMaxSpeed;
                fRec[i].fScale = 1;
                fRec[i].fDScale = rand.nextSScalar1() / 16;
                fRec[i].fRadian = 0;
                fRec[i].fDRadian = rand.nextSScalar1() / 8;
                fRec[i].fAlpha = rand.nextUScalar1();
                fRec[i].fDAlpha = rand.nextSScalar1() / 10;
                i += 1;
            }
        }
    }

    void onDraw(SkCanvas* canvas) override {
        SkPath path;
        SkRandom rand;

        int scale = 300;
        for (int i = 0; i < 4; ++i) {
            // get the random values deterministically
            SkScalar randoms[12];
            for (int index = 0; index < (int) SK_ARRAY_COUNT(randoms); ++index) {
                randoms[index] = rand.nextUScalar1();
            }
            path.lineTo(randoms[0] * scale, randoms[1] * scale);
            path.quadTo(randoms[2] * scale, randoms[3] * scale,
                        randoms[4] * scale, randoms[5] * scale);
            path.cubicTo(randoms[6] * scale, randoms[7] * scale,
                         randoms[8] * scale, randoms[9] * scale,
                         randoms[10] * scale, randoms[11] * scale);
        }

        path.setFillType(SkPath::kEvenOdd_FillType);
        path.offset(SkIntToScalar(20), SkIntToScalar(20));

        test_hittest(canvas, path);

        canvas->translate(SkIntToScalar(scale), 0);
        path.setFillType(SkPath::kWinding_FillType);

        test_hittest(canvas, path);
    }

static void test_memory_pool(skiatest::Reporter* reporter) {
    // prealloc and min alloc sizes for the pool
    static const size_t gSizes[][2] = {
        {0, 0},
        {10 * sizeof(A), 20 * sizeof(A)},
        {100 * sizeof(A), 100 * sizeof(A)},
        {500 * sizeof(A), 500 * sizeof(A)},
        {10000 * sizeof(A), 0},
        {1, 100 * sizeof(A)},
    };
    // different percentages of creation vs deletion
    static const float gCreateFraction[] = {1.f, .95f, 0.75f, .5f};
    // number of create/destroys per test
    static const int kNumIters = 20000;
    // check that all the values stored in A objects are correct after this
    // number of iterations
    static const int kCheckPeriod = 500;

    SkRandom r;
    for (size_t s = 0; s < SK_ARRAY_COUNT(gSizes); ++s) {
        A::SetAllocator(gSizes[s][0], gSizes[s][1]);
        for (size_t c = 0; c < SK_ARRAY_COUNT(gCreateFraction); ++c) {
            SkTDArray<Rec> instanceRecs;
            for (int i = 0; i < kNumIters; ++i) {
                float createOrDestroy = r.nextUScalar1();
                if (createOrDestroy < gCreateFraction[c] ||
                    0 == instanceRecs.count()) {
                    Rec* rec = instanceRecs.append();
                    rec->fInstance = A::Create(&r);
                    rec->fValue = static_cast<int>(r.nextU());
                    rec->fInstance->setValues(rec->fValue);
                } else {
                    int d = r.nextRangeU(0, instanceRecs.count() - 1);
                    Rec& rec = instanceRecs[d];
                    REPORTER_ASSERT(reporter, rec.fInstance->checkValues(rec.fValue));
                    delete rec.fInstance;
                    instanceRecs.removeShuffle(d);
                }
                if (0 == i % kCheckPeriod) {
                    for (int r = 0; r < instanceRecs.count(); ++r) {
                        Rec& rec = instanceRecs[r];
                        REPORTER_ASSERT(reporter, rec.fInstance->checkValues(rec.fValue));
                    }
                }
            }
            for (int i = 0; i < instanceRecs.count(); ++i) {
                Rec& rec = instanceRecs[i];
                REPORTER_ASSERT(reporter, rec.fInstance->checkValues(rec.fValue));
                delete rec.fInstance;
            }
#ifdef SK_ENABLE_INST_COUNT
            REPORTER_ASSERT(reporter, !A::GetInstanceCount());
#endif
        }
    }
}