SkDraw.h

/*
 * Copyright 2006 The Android Open Source Project
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */


#ifndef SkDraw_DEFINED
#define SkDraw_DEFINED

#include "SkCanvas.h"
#include "SkMask.h"
#include "SkPaint.h"
#include "SkStrokeRec.h"

class SkBitmap;
class SkClipStack;
class SkBaseDevice;
class SkBlitter;
class SkMatrix;
class SkPath;
class SkRegion;
class SkRasterClip;
struct SkDrawProcs;
struct SkRect;
class SkRRect;

class SkDraw {
public:
    SkDraw();

    void    drawPaint(const SkPaint&) const;
    void    drawPoints(SkCanvas::PointMode, size_t count, const SkPoint[],
                       const SkPaint&, bool forceUseDevice = false) const;
    void    drawRect(const SkRect& prePaintRect, const SkPaint&, const SkMatrix* paintMatrix,
                     const SkRect* postPaintRect) const;
    void    drawRect(const SkRect& rect, const SkPaint& paint) const {
        this->drawRect(rect, paint, NULL, NULL);
    }
    void    drawRRect(const SkRRect&, const SkPaint&) const;
    void    drawPath(const SkPath& path, const SkPaint& paint,
                     const SkMatrix* prePathMatrix, bool pathIsMutable) const {
        this->drawPath(path, paint, prePathMatrix, pathIsMutable, false);
    }

    void drawPath(const SkPath& path, const SkPaint& paint,
                  SkBlitter* customBlitter = NULL) const {
        this->drawPath(path, paint, NULL, false, false, customBlitter);
    }

    /* If dstOrNull is null, computes a dst by mapping the bitmap's bounds through the matrix. */
    void    drawBitmap(const SkBitmap&, const SkMatrix&, const SkRect* dstOrNull,
                       const SkPaint&) const;
    void    drawSprite(const SkBitmap&, int x, int y, const SkPaint&) const;
    void    drawText(const char text[], size_t byteLength, SkScalar x,
                     SkScalar y, const SkPaint& paint) const;
    void    drawPosText(const char text[], size_t byteLength,
                        const SkScalar pos[], int scalarsPerPosition,
                        const SkPoint& offset, const SkPaint& paint) const;
    void    drawVertices(SkCanvas::VertexMode mode, int count,
                         const SkPoint vertices[], const SkPoint textures[],
                         const SkColor colors[], SkXfermode* xmode,
                         const uint16_t indices[], int ptCount,
                         const SkPaint& paint) const;

    void drawPathCoverage(const SkPath& src, const SkPaint& paint,
                          SkBlitter* customBlitter = NULL) const {
        this->drawPath(src, paint, NULL, false, true, customBlitter);
    }

    static bool DrawToMask(const SkPath& devPath, const SkIRect* clipBounds,
                           const SkMaskFilter*, const SkMatrix* filterMatrix,
                           SkMask* mask, SkMask::CreateMode mode,
                           SkStrokeRec::InitStyle style);

    enum RectType {
        kHair_RectType,
        kFill_RectType,
        kStroke_RectType,
        kPath_RectType
    };

    static RectType ComputeRectType(const SkPaint&, const SkMatrix&,
                                    SkPoint* strokeSize);

    static bool ShouldDrawTextAsPaths(const SkPaint&, const SkMatrix&);
    void        drawText_asPaths(const char text[], size_t byteLength,
                                 SkScalar x, SkScalar y, const SkPaint&) const;
    void        drawPosText_asPaths(const char text[], size_t byteLength,
                                    const SkScalar pos[], int scalarsPerPosition,
                                    const SkPoint& offset, const SkPaint&) const;
    static SkScalar ComputeResScaleForStroking(const SkMatrix& );
private:
    void    drawDevMask(const SkMask& mask, const SkPaint&) const;
    void    drawBitmapAsMask(const SkBitmap&, const SkPaint&) const;

    void    drawPath(const SkPath&, const SkPaint&, const SkMatrix* preMatrix,
                     bool pathIsMutable, bool drawCoverage,
                     SkBlitter* customBlitter = NULL) const;

    void drawLine(const SkPoint[2], const SkPaint&) const;
    void drawDevPath(const SkPath& devPath, const SkPaint& paint, bool drawCoverage,
                     SkBlitter* customBlitter, bool doFill) const;
    bool SK_WARN_UNUSED_RESULT
    computeConservativeLocalClipBounds(SkRect* bounds) const;

    uint32_t SK_WARN_UNUSED_RESULT scalerContextFlags() const;

public:
    SkPixmap        fDst;
    const SkMatrix* fMatrix;        // required
    const SkRasterClip* fRC;        // required

    const SkClipStack* fClipStack;  // optional, may be null
    SkBaseDevice*   fDevice;        // optional, may be null

#ifdef SK_DEBUG
    void validate() const;
#else
    void validate() const {}
#endif
};

#endif