SkPDFImageShader::SkPDFImageShader(SkPDFShader::State* state) : fState(state) {
    fState.get()->fImage.lockPixels();

    SkMatrix finalMatrix = fState.get()->fCanvasTransform;
    finalMatrix.preConcat(fState.get()->fShaderTransform);
    SkRect surfaceBBox;
    surfaceBBox.set(fState.get()->fBBox);
    transformBBox(finalMatrix, &surfaceBBox);

    SkMatrix unflip;
    unflip.setTranslate(0, SkScalarRound(surfaceBBox.height()));
    unflip.preScale(SK_Scalar1, -SK_Scalar1);
    SkISize size = SkISize::Make(SkScalarRound(surfaceBBox.width()),
                                 SkScalarRound(surfaceBBox.height()));
    SkPDFDevice pattern(size, size, unflip);
    SkCanvas canvas(&pattern);
    canvas.translate(-surfaceBBox.fLeft, -surfaceBBox.fTop);
    finalMatrix.preTranslate(surfaceBBox.fLeft, surfaceBBox.fTop);

    const SkBitmap* image = &fState.get()->fImage;
    int width = image->width();
    int height = image->height();
    SkShader::TileMode tileModes[2];
    tileModes[0] = fState.get()->fImageTileModes[0];
    tileModes[1] = fState.get()->fImageTileModes[1];

    canvas.drawBitmap(*image, 0, 0);
    SkRect patternBBox = SkRect::MakeXYWH(-surfaceBBox.fLeft, -surfaceBBox.fTop,
                                          width, height);

    // Tiling is implied.  First we handle mirroring.
    if (tileModes[0] == SkShader::kMirror_TileMode) {
        SkMatrix xMirror;
        xMirror.setScale(-1, 1);
        xMirror.postTranslate(2 * width, 0);
        canvas.drawBitmapMatrix(*image, xMirror);
        patternBBox.fRight += width;
    }
    if (tileModes[1] == SkShader::kMirror_TileMode) {
        SkMatrix yMirror;
        yMirror.setScale(SK_Scalar1, -SK_Scalar1);
        yMirror.postTranslate(0, 2 * height);
        canvas.drawBitmapMatrix(*image, yMirror);
        patternBBox.fBottom += height;
    }
    if (tileModes[0] == SkShader::kMirror_TileMode &&
            tileModes[1] == SkShader::kMirror_TileMode) {
        SkMatrix mirror;
        mirror.setScale(-1, -1);
        mirror.postTranslate(2 * width, 2 * height);
        canvas.drawBitmapMatrix(*image, mirror);
    }

    // Then handle Clamping, which requires expanding the pattern canvas to
    // cover the entire surfaceBBox.

    // If both x and y are in clamp mode, we start by filling in the corners.
    // (Which are just a rectangles of the corner colors.)
    if (tileModes[0] == SkShader::kClamp_TileMode &&
            tileModes[1] == SkShader::kClamp_TileMode) {
        SkPaint paint;
        SkRect rect;
        rect = SkRect::MakeLTRB(surfaceBBox.fLeft, surfaceBBox.fTop, 0, 0);
        if (!rect.isEmpty()) {
            paint.setColor(image->getColor(0, 0));
            canvas.drawRect(rect, paint);
        }

        rect = SkRect::MakeLTRB(width, surfaceBBox.fTop, surfaceBBox.fRight, 0);
        if (!rect.isEmpty()) {
            paint.setColor(image->getColor(width - 1, 0));
            canvas.drawRect(rect, paint);
        }

        rect = SkRect::MakeLTRB(width, height, surfaceBBox.fRight,
                                surfaceBBox.fBottom);
        if (!rect.isEmpty()) {
            paint.setColor(image->getColor(width - 1, height - 1));
            canvas.drawRect(rect, paint);
        }

        rect = SkRect::MakeLTRB(surfaceBBox.fLeft, height, 0,
                                surfaceBBox.fBottom);
        if (!rect.isEmpty()) {
            paint.setColor(image->getColor(0, height - 1));
            canvas.drawRect(rect, paint);
        }
    }

    // Then expand the left, right, top, then bottom.
    if (tileModes[0] == SkShader::kClamp_TileMode) {
        SkIRect subset = SkIRect::MakeXYWH(0, 0, 1, height);
        if (surfaceBBox.fLeft < 0) {
            SkBitmap left;
            SkAssertResult(image->extractSubset(&left, subset));

            SkMatrix leftMatrix;
            leftMatrix.setScale(-surfaceBBox.fLeft, 1);
            leftMatrix.postTranslate(surfaceBBox.fLeft, 0);
            canvas.drawBitmapMatrix(left, leftMatrix);

            if (tileModes[1] == SkShader::kMirror_TileMode) {
                leftMatrix.postScale(SK_Scalar1, -SK_Scalar1);
                leftMatrix.postTranslate(0, 2 * height);
                canvas.drawBitmapMatrix(left, leftMatrix);
            }
            patternBBox.fLeft = 0;
        }

        if (surfaceBBox.fRight > width) {
            SkBitmap right;
            subset.offset(width - 1, 0);
            SkAssertResult(image->extractSubset(&right, subset));

            SkMatrix rightMatrix;
            rightMatrix.setScale(surfaceBBox.fRight - width, 1);
            rightMatrix.postTranslate(width, 0);
            canvas.drawBitmapMatrix(right, rightMatrix);

            if (tileModes[1] == SkShader::kMirror_TileMode) {
                rightMatrix.postScale(SK_Scalar1, -SK_Scalar1);
                rightMatrix.postTranslate(0, 2 * height);
                canvas.drawBitmapMatrix(right, rightMatrix);
            }
            patternBBox.fRight = surfaceBBox.width();
        }
    }

    if (tileModes[1] == SkShader::kClamp_TileMode) {
        SkIRect subset = SkIRect::MakeXYWH(0, 0, width, 1);
        if (surfaceBBox.fTop < 0) {
            SkBitmap top;
            SkAssertResult(image->extractSubset(&top, subset));

            SkMatrix topMatrix;
            topMatrix.setScale(SK_Scalar1, -surfaceBBox.fTop);
            topMatrix.postTranslate(0, surfaceBBox.fTop);
            canvas.drawBitmapMatrix(top, topMatrix);

            if (tileModes[0] == SkShader::kMirror_TileMode) {
                topMatrix.postScale(-1, 1);
                topMatrix.postTranslate(2 * width, 0);
                canvas.drawBitmapMatrix(top, topMatrix);
            }
            patternBBox.fTop = 0;
        }

        if (surfaceBBox.fBottom > height) {
            SkBitmap bottom;
            subset.offset(0, height - 1);
            SkAssertResult(image->extractSubset(&bottom, subset));

            SkMatrix bottomMatrix;
            bottomMatrix.setScale(SK_Scalar1, surfaceBBox.fBottom - height);
            bottomMatrix.postTranslate(0, height);
            canvas.drawBitmapMatrix(bottom, bottomMatrix);

            if (tileModes[0] == SkShader::kMirror_TileMode) {
                bottomMatrix.postScale(-1, 1);
                bottomMatrix.postTranslate(2 * width, 0);
                canvas.drawBitmapMatrix(bottom, bottomMatrix);
            }
            patternBBox.fBottom = surfaceBBox.height();
        }
    }

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

    // Put the canvas into the pattern stream (fContent).
    SkRefPtr<SkStream> content = pattern.content();
    content->unref();  // SkRefPtr and content() both took a reference.
    pattern.getResources(&fResources);

    setData(content.get());
    insertName("Type", "Pattern");
    insertInt("PatternType", 1);
    insertInt("PaintType", 1);
    insertInt("TilingType", 1);
    insert("BBox", patternBBoxArray.get());
    insertScalar("XStep", patternBBox.width());
    insertScalar("YStep", patternBBox.height());
    insert("Resources", pattern.getResourceDict());
    insert("Matrix", SkPDFUtils::MatrixToArray(finalMatrix))->unref();

    fState.get()->fImage.unlockPixels();
}
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());
}