C++ SkMatrix::mapRadius方法代码示例

bool SkBlurMaskFilterImpl::filterMask(SkMask* dst, const SkMask& src, const SkMatrix& matrix, SkIPoint* margin)
{
    SkScalar radius;
    if (fBlurFlags & SkBlurMaskFilter::kIgnoreTransform_BlurFlag)
        radius = fRadius;
    else
        radius = matrix.mapRadius(fRadius);

    // To avoid unseemly allocation requests (esp. for finite platforms like
    // handset) we limit the radius so something manageable. (as opposed to
    // a request like 10,000)
    static const SkScalar MAX_RADIUS = SkIntToScalar(128);
    radius = SkMinScalar(radius, MAX_RADIUS);
    SkBlurMask::Quality blurQuality = (fBlurFlags & SkBlurMaskFilter::kHighQuality_BlurFlag) ?
                                      SkBlurMask::kHigh_Quality : SkBlurMask::kLow_Quality;

    if (SkBlurMask::Blur(dst, src, radius, (SkBlurMask::Style)fBlurStyle, blurQuality))
    {
        if (margin) {
            // we need to integralize radius for our margin, so take the ceil
            // just to be safe.
            margin->set(SkScalarCeil(radius), SkScalarCeil(radius));
        }
        return true;
    }
    return false;
}

Float Matrix::NativeMapRadius(
    /* [in] */ Int64 matrixHandle,
    /* [in] */ Float radius)
{
    SkMatrix* matrix = reinterpret_cast<SkMatrix*>(matrixHandle);
    Float result;
    result = SkScalarToFloat(matrix->mapRadius(radius));
    return static_cast<Float>(result);
}

bool SkEmbossMaskFilter::filterMask(SkMask* dst, const SkMask& src,
                                    const SkMatrix& matrix, SkIPoint* margin) const {
    SkScalar sigma = matrix.mapRadius(fBlurSigma);

    if (!SkBlurMask::BoxBlur(dst, src, sigma, SkBlurMask::kInner_Style,
                             SkBlurMask::kLow_Quality)) {
        return false;
    }

    dst->fFormat = SkMask::k3D_Format;
    if (margin) {
        margin->set(SkScalarCeilToInt(3*sigma), SkScalarCeilToInt(3*sigma));
    }

    if (src.fImage == NULL) {
        return true;
    }

    // create a larger buffer for the other two channels (should force fBlur to do this for us)

    {
        uint8_t* alphaPlane = dst->fImage;
        size_t   planeSize = dst->computeImageSize();
        if (0 == planeSize) {
            return false;   // too big to allocate, abort
        }
        dst->fImage = SkMask::AllocImage(planeSize * 3);
        memcpy(dst->fImage, alphaPlane, planeSize);
        SkMask::FreeImage(alphaPlane);
    }

    // run the light direction through the matrix...
    Light   light = fLight;
    matrix.mapVectors((SkVector*)(void*)light.fDirection,
                      (SkVector*)(void*)fLight.fDirection, 1);

    // now restore the length of the XY component
    // cast to SkVector so we can call setLength (this double cast silences alias warnings)
    SkVector* vec = (SkVector*)(void*)light.fDirection;
    vec->setLength(light.fDirection[0],
                   light.fDirection[1],
                   SkPoint::Length(fLight.fDirection[0], fLight.fDirection[1]));

    SkEmbossMask::Emboss(dst, light);

    // restore original alpha
    memcpy(dst->fImage, src.fImage, src.computeImageSize());

    return true;
}

SkScalar GrPathUtils::scaleToleranceToSrc(SkScalar devTol,
                                          const SkMatrix& viewM,
                                          const SkRect& pathBounds) {
    // In order to tesselate the path we get a bound on how much the matrix can
    // scale when mapping to screen coordinates.
    SkScalar stretch = viewM.getMaxScale();
    SkScalar srcTol = devTol;

    if (stretch < 0) {
        // take worst case mapRadius amoung four corners.
        // (less than perfect)
        for (int i = 0; i < 4; ++i) {
            SkMatrix mat;
            mat.setTranslate((i % 2) ? pathBounds.fLeft : pathBounds.fRight,
                             (i < 2) ? pathBounds.fTop : pathBounds.fBottom);
            mat.postConcat(viewM);
            stretch = SkMaxScalar(stretch, mat.mapRadius(SK_Scalar1));
        }
    }
    return srcTol / stretch;
}

SkPDFFunctionShader::SkPDFFunctionShader(SkPDFShader::State* state)
        : SkPDFDict("Pattern"),
          fState(state) {
    SkString (*codeFunction)(const SkShader::GradientInfo& info) = NULL;
    SkPoint transformPoints[2];

    // Depending on the type of the gradient, we want to transform the
    // coordinate space in different ways.
    const SkShader::GradientInfo* info = &fState.get()->fInfo;
    transformPoints[0] = info->fPoint[0];
    transformPoints[1] = info->fPoint[1];
    switch (fState.get()->fType) {
        case SkShader::kLinear_GradientType:
            codeFunction = &linearCode;
            break;
        case SkShader::kRadial_GradientType:
            transformPoints[1] = transformPoints[0];
            transformPoints[1].fX += info->fRadius[0];
            codeFunction = &radialCode;
            break;
        case SkShader::kRadial2_GradientType: {
            // Bail out if the radii are the same.  Empty fResources signals
            // an error and isValid will return false.
            if (info->fRadius[0] == info->fRadius[1]) {
                return;
            }
            transformPoints[1] = transformPoints[0];
            SkScalar dr = info->fRadius[1] - info->fRadius[0];
            transformPoints[1].fX += dr;
            codeFunction = &twoPointRadialCode;
            break;
        }
        case SkShader::kSweep_GradientType:
            transformPoints[1] = transformPoints[0];
            transformPoints[1].fX += 1;
            codeFunction = &sweepCode;
            break;
        case SkShader::kColor_GradientType:
        case SkShader::kNone_GradientType:
        default:
            return;
    }

    // Move any scaling (assuming a unit gradient) or translation
    // (and rotation for linear gradient), of the final gradient from
    // info->fPoints to the matrix (updating bbox appropriately).  Now
    // the gradient can be drawn on on the unit segment.
    SkMatrix mapperMatrix;
    unitToPointsMatrix(transformPoints, &mapperMatrix);
    SkMatrix finalMatrix = fState.get()->fCanvasTransform;
    finalMatrix.preConcat(mapperMatrix);
    finalMatrix.preConcat(fState.get()->fShaderTransform);
    SkRect bbox;
    bbox.set(fState.get()->fBBox);
    transformBBox(finalMatrix, &bbox);

    SkRefPtr<SkPDFArray> domain = new SkPDFArray;
    domain->unref();  // SkRefPtr and new both took a reference.
    domain->reserve(4);
    domain->appendScalar(bbox.fLeft);
    domain->appendScalar(bbox.fRight);
    domain->appendScalar(bbox.fTop);
    domain->appendScalar(bbox.fBottom);

    SkString functionCode;
    // The two point radial gradient further references fState.get()->fInfo
    // in translating from x, y coordinates to the t parameter. So, we have
    // to transform the points and radii according to the calculated matrix.
    if (fState.get()->fType == SkShader::kRadial2_GradientType) {
        SkShader::GradientInfo twoPointRadialInfo = *info;
        SkMatrix inverseMapperMatrix;
        mapperMatrix.invert(&inverseMapperMatrix);
        inverseMapperMatrix.mapPoints(twoPointRadialInfo.fPoint, 2);
        twoPointRadialInfo.fRadius[0] =
            inverseMapperMatrix.mapRadius(info->fRadius[0]);
        twoPointRadialInfo.fRadius[1] =
            inverseMapperMatrix.mapRadius(info->fRadius[1]);
        functionCode = codeFunction(twoPointRadialInfo);
    } else {
        functionCode = codeFunction(*info);
    }

    SkRefPtr<SkPDFStream> function = makePSFunction(functionCode, domain.get());
    // Pass one reference to fResources, SkRefPtr and new both took a reference.
    fResources.push(function.get());

    SkRefPtr<SkPDFDict> pdfShader = new SkPDFDict;
    pdfShader->unref();  // SkRefPtr and new both took a reference.
    pdfShader->insertInt("ShadingType", 1);
    pdfShader->insertName("ColorSpace", "DeviceRGB");
    pdfShader->insert("Domain", domain.get());
    pdfShader->insert("Function", new SkPDFObjRef(function.get()))->unref();

    insertInt("PatternType", 2);
    insert("Matrix", SkPDFUtils::MatrixToArray(finalMatrix))->unref();
    insert("Shading", pdfShader.get());
}

//.........这里部分代码省略.........
            codeFunction = &twoPointRadialCode;
            break;
        }
        case SkShader::kConical_GradientType: {
            transformPoints[1] = transformPoints[0];
            transformPoints[1].fX += SK_Scalar1;
            codeFunction = &twoPointConicalCode;
            break;
        }
        case SkShader::kSweep_GradientType:
            transformPoints[1] = transformPoints[0];
            transformPoints[1].fX += SK_Scalar1;
            codeFunction = &sweepCode;
            break;
        case SkShader::kColor_GradientType:
        case SkShader::kNone_GradientType:
        default:
            return NULL;
    }

    // Move any scaling (assuming a unit gradient) or translation
    // (and rotation for linear gradient), of the final gradient from
    // info->fPoints to the matrix (updating bbox appropriately).  Now
    // the gradient can be drawn on on the unit segment.
    SkMatrix mapperMatrix;
    unitToPointsMatrix(transformPoints, &mapperMatrix);

    SkMatrix finalMatrix = state.fCanvasTransform;
    finalMatrix.preConcat(state.fShaderTransform);
    finalMatrix.preConcat(mapperMatrix);

    // Preserves as much as posible in the final matrix, and only removes
    // the perspective. The inverse of the perspective is stored in
    // perspectiveInverseOnly matrix and has 3 useful numbers
    // (p0, p1, p2), while everything else is either 0 or 1.
    // In this way the shader will handle it eficiently, with minimal code.
    SkMatrix perspectiveInverseOnly = SkMatrix::I();
    if (finalMatrix.hasPerspective()) {
        if (!split_perspective(finalMatrix,
                               &finalMatrix, &perspectiveInverseOnly)) {
            return NULL;
        }
    }

    SkRect bbox;
    bbox.set(state.fBBox);
    if (!inverse_transform_bbox(finalMatrix, &bbox)) {
        return NULL;
    }

    SkAutoTUnref<SkPDFArray> domain(new SkPDFArray);
    domain->reserve(4);
    domain->appendScalar(bbox.fLeft);
    domain->appendScalar(bbox.fRight);
    domain->appendScalar(bbox.fTop);
    domain->appendScalar(bbox.fBottom);

    SkString functionCode;
    // The two point radial gradient further references
    // state.fInfo
    // in translating from x, y coordinates to the t parameter. So, we have
    // to transform the points and radii according to the calculated matrix.
    if (state.fType == SkShader::kRadial2_GradientType) {
        SkShader::GradientInfo twoPointRadialInfo = *info;
        SkMatrix inverseMapperMatrix;
        if (!mapperMatrix.invert(&inverseMapperMatrix)) {
            return NULL;
        }
        inverseMapperMatrix.mapPoints(twoPointRadialInfo.fPoint, 2);
        twoPointRadialInfo.fRadius[0] =
            inverseMapperMatrix.mapRadius(info->fRadius[0]);
        twoPointRadialInfo.fRadius[1] =
            inverseMapperMatrix.mapRadius(info->fRadius[1]);
        functionCode = codeFunction(twoPointRadialInfo, perspectiveInverseOnly);
    } else {
        functionCode = codeFunction(*info, perspectiveInverseOnly);
    }

    SkAutoTUnref<SkPDFDict> pdfShader(new SkPDFDict);
    pdfShader->insertInt("ShadingType", 1);
    pdfShader->insertName("ColorSpace", "DeviceRGB");
    pdfShader->insert("Domain", domain.get());

    SkAutoTUnref<SkPDFStream> function(
            make_ps_function(functionCode, domain.get()));
    pdfShader->insert("Function", new SkPDFObjRef(function))->unref();

    SkAutoTUnref<SkPDFArray> matrixArray(
            SkPDFUtils::MatrixToArray(finalMatrix));

    SkPDFFunctionShader* pdfFunctionShader =
            SkNEW_ARGS(SkPDFFunctionShader, (autoState->detach()));

    pdfFunctionShader->insertInt("PatternType", 2);
    pdfFunctionShader->insert("Matrix", matrixArray.get());
    pdfFunctionShader->insert("Shading", pdfShader.get());

    canon->addFunctionShader(pdfFunctionShader);
    return pdfFunctionShader;
}

 static jfloat mapRadius(JNIEnv* env, jobject clazz, jlong matrixHandle, jfloat radius) {
     SkMatrix* matrix = reinterpret_cast<SkMatrix*>(matrixHandle);
     float result;
     result = SkScalarToFloat(matrix->mapRadius(radius));
     return static_cast<jfloat>(result);
 }