auto import from //depot/cupcake/@135843

1 files changed, 794 insertions, 0 deletions

diff --git a/include/core/SkCanvas.h b/include/core/SkCanvas.h
new file mode 100644
index 0000000..a19a5ae
--- /dev/null
+++ b/include/core/SkCanvas.h
@@ -0,0 +1,794 @@
+/*
+ * Copyright (C) 2006 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef SkCanvas_DEFINED
+#define SkCanvas_DEFINED
+
+#include "SkTypes.h"
+#include "SkBitmap.h"
+#include "SkDeque.h"
+#include "SkPaint.h"
+#include "SkRefCnt.h"
+#include "SkPorterDuff.h"
+#include "SkPath.h"
+#include "SkRegion.h"
+#include "SkScalarCompare.h"
+
+class SkBounder;
+class SkDevice;
+class SkDraw;
+class SkDrawFilter;
+class SkPicture;
+
+/** \class SkCanvas
+
+    A Canvas encapsulates all of the state about drawing into a device (bitmap).
+    This includes a reference to the device itself, and a stack of matrix/clip
+    values. For any given draw call (e.g. drawRect), the geometry of the object
+    being drawn is transformed by the concatenation of all the matrices in the
+    stack. The transformed geometry is clipped by the intersection of all of
+    the clips in the stack.
+
+    While the Canvas holds the state of the drawing device, the state (style)
+    of the object being drawn is held by the Paint, which is provided as a
+    parameter to each of the draw() methods. The Paint holds attributes such as
+    color, typeface, textSize, strokeWidth, shader (e.g. gradients, patterns),
+    etc.
+*/
+class SkCanvas : public SkRefCnt {
+public:
+    /** Construct a canvas with the specified bitmap to draw into.
+        @param bitmap   Specifies a bitmap for the canvas to draw into. Its
+                        structure are copied to the canvas.
+    */
+    explicit SkCanvas(const SkBitmap& bitmap);
+    /** Construct a canvas with the specified device to draw into.
+        @param device   Specifies a device for the canvas to draw into. The
+                        device may be null.
+    */
+    explicit SkCanvas(SkDevice* device = NULL);
+    virtual ~SkCanvas();
+
+    ///////////////////////////////////////////////////////////////////////////
+
+    /** If this subclass of SkCanvas supports GL viewports, return true and set
+        size (if not null) to the size of the viewport. If it is not supported,
+        ignore vp and return false.
+    */
+    virtual bool getViewport(SkIPoint* size) const;
+    
+    /** If this subclass of SkCanvas supports GL viewports, return true and set
+        the viewport to the specified x and y dimensions. If it is not
+        supported, ignore x and y and return false.
+    */
+    virtual bool setViewport(int x, int y);
+
+    /** Return the canvas' device object, which may be null. The device holds
+        the bitmap of the pixels that the canvas draws into. The reference count
+        of the returned device is not changed by this call.
+    */
+    SkDevice* getDevice() const;
+
+    /** Specify a device for this canvas to draw into. If it is not null, its
+        reference count is incremented. If the canvas was already holding a
+        device, its reference count is decremented. The new device is returned.
+    */
+    SkDevice* setDevice(SkDevice* device);
+    
+    /** Specify a bitmap for the canvas to draw into. This is a help method for
+        setDevice(), and it creates a device for the bitmap by calling
+        createDevice(). The structure of the bitmap is copied into the device.
+    */
+    virtual SkDevice* setBitmapDevice(const SkBitmap& bitmap);
+
+    ///////////////////////////////////////////////////////////////////////////
+    
+    enum SaveFlags {
+        /** save the matrix state, restoring it on restore() */
+        kMatrix_SaveFlag            = 0x01,
+        /** save the clip state, restoring it on restore() */
+        kClip_SaveFlag              = 0x02,
+        /** the layer needs to support per-pixel alpha */
+        kHasAlphaLayer_SaveFlag     = 0x04,
+        /** the layer needs to support 8-bits per color component */
+        kFullColorLayer_SaveFlag    = 0x08,
+        /** the layer should clip against the bounds argument */
+        kClipToLayer_SaveFlag       = 0x10,
+
+        // helper masks for common choices
+        kMatrixClip_SaveFlag        = 0x03,
+        kARGB_NoClipLayer_SaveFlag  = 0x0F,
+        kARGB_ClipLayer_SaveFlag    = 0x1F
+    };
+
+    /** This call saves the current matrix and clip information, and pushes a
+        copy onto a private stack. Subsequent calls to translate, scale,
+        rotate, skew, concat or clipRect, clipPath all operate on this copy.
+        When the balancing call to restore() is made, this copy is deleted and
+        the previous matrix/clip state is restored.
+        @return The value to pass to restoreToCount() to balance this save()
+    */
+    virtual int save(SaveFlags flags = kMatrixClip_SaveFlag);
+
+    /** This behaves the same as save(), but in addition it allocates an
+        offscreen bitmap. All drawing calls are directed there, and only when
+        the balancing call to restore() is made is that offscreen transfered to
+        the canvas (or the previous layer). Subsequent calls to translate,
+        scale, rotate, skew, concat or clipRect, clipPath all operate on this
+        copy. When the balancing call to restore() is made, this copy is deleted
+        and the previous matrix/clip state is restored.
+        @param bounds (may be null) the maximum size the offscreen bitmap needs
+                      to be (in local coordinates)
+        @param paint (may be null) This is copied, and is applied to the
+                     offscreen when restore() is called
+        @param flags  LayerFlags
+        @return The value to pass to restoreToCount() to balance this save()
+    */
+    virtual int saveLayer(const SkRect* bounds, const SkPaint* paint,
+                          SaveFlags flags = kARGB_ClipLayer_SaveFlag);
+
+    /** This behaves the same as save(), but in addition it allocates an
+        offscreen bitmap. All drawing calls are directed there, and only when
+        the balancing call to restore() is made is that offscreen transfered to
+        the canvas (or the previous layer). Subsequent calls to translate,
+        scale, rotate, skew, concat or clipRect, clipPath all operate on this
+        copy. When the balancing call to restore() is made, this copy is deleted
+        and the previous matrix/clip state is restored.
+        @param bounds (may be null) the maximum size the offscreen bitmap needs
+                      to be (in local coordinates)
+        @param alpha  This is applied to the offscreen when restore() is called.
+        @param flags  LayerFlags
+        @return The value to pass to restoreToCount() to balance this save()
+    */
+    int saveLayerAlpha(const SkRect* bounds, U8CPU alpha,
+                       SaveFlags flags = kARGB_ClipLayer_SaveFlag);
+
+    /** This call balances a previous call to save(), and is used to remove all
+        modifications to the matrix/clip state since the last save call. It is
+        an error to call restore() more times than save() was called.
+    */
+    virtual void restore();
+
+    /** Returns the number of matrix/clip states on the SkCanvas' private stack.
+        This will equal # save() calls - # restore() calls.
+    */
+    int getSaveCount() const;
+
+    /** Efficient way to pop any calls to save() that happened after the save
+        count reached saveCount. It is an error for saveCount to be less than
+        getSaveCount()
+        @param saveCount    The number of save() levels to restore from
+    */
+    void restoreToCount(int saveCount);
+
+    /** Preconcat the current matrix with the specified translation
+        @param dx   The distance to translate in X
+        @param dy   The distance to translate in Y
+        returns true if the operation succeeded (e.g. did not overflow)
+    */
+    virtual bool translate(SkScalar dx, SkScalar dy);
+
+    /** Preconcat the current matrix with the specified scale.
+        @param sx   The amount to scale in X
+        @param sy   The amount to scale in Y
+        returns true if the operation succeeded (e.g. did not overflow)
+    */
+    virtual bool scale(SkScalar sx, SkScalar sy);
+
+    /** Preconcat the current matrix with the specified rotation.
+        @param degrees  The amount to rotate, in degrees
+        returns true if the operation succeeded (e.g. did not overflow)
+    */
+    virtual bool rotate(SkScalar degrees);
+
+    /** Preconcat the current matrix with the specified skew.
+        @param sx   The amount to skew in X
+        @param sy   The amount to skew in Y
+        returns true if the operation succeeded (e.g. did not overflow)
+    */
+    virtual bool skew(SkScalar sx, SkScalar sy);
+
+    /** Preconcat the current matrix with the specified matrix.
+        @param matrix   The matrix to preconcatenate with the current matrix
+        @return true if the operation succeeded (e.g. did not overflow)
+    */
+    virtual bool concat(const SkMatrix& matrix);
+    
+    /** Replace the current matrix with a copy of the specified matrix.
+        @param matrix The matrix that will be copied into the current matrix.
+    */
+    virtual void setMatrix(const SkMatrix& matrix);
+    
+    /** Helper for setMatrix(identity). Sets the current matrix to identity.
+    */
+    void resetMatrix();
+
+    /** Modify the current clip with the specified rectangle.
+        @param rect The rect to intersect with the current clip
+        @param op The region op to apply to the current clip
+        @return true if the canvas' clip is non-empty
+    */
+    virtual bool clipRect(const SkRect& rect,
+                          SkRegion::Op op = SkRegion::kIntersect_Op);
+
+    /** Modify the current clip with the specified path.
+        @param path The path to apply to the current clip
+        @param op The region op to apply to the current clip
+        @return true if the canvas' new clip is non-empty
+    */
+    virtual bool clipPath(const SkPath& path,
+                          SkRegion::Op op = SkRegion::kIntersect_Op);
+
+    /** Modify the current clip with the specified region. Note that unlike
+        clipRect() and clipPath() which transform their arguments by the current
+        matrix, clipRegion() assumes its argument is already in device
+        coordinates, and so no transformation is performed.
+        @param deviceRgn    The region to apply to the current clip
+        @param op The region op to apply to the current clip
+        @return true if the canvas' new clip is non-empty
+    */
+    virtual bool clipRegion(const SkRegion& deviceRgn,
+                            SkRegion::Op op = SkRegion::kIntersect_Op);
+
+    /** Helper for clipRegion(rgn, kReplace_Op). Sets the current clip to the
+        specified region. This does not intersect or in any other way account
+        for the existing clip region.
+        @param deviceRgn The region to copy into the current clip.
+        @return true if the new clip region is non-empty
+    */
+    bool setClipRegion(const SkRegion& deviceRgn) {
+        return this->clipRegion(deviceRgn, SkRegion::kReplace_Op);
+    }
+
+    /** Enum describing how to treat edges when performing quick-reject tests
+        of a geometry against the current clip. Treating them as antialiased
+        (kAA_EdgeType) will take into account the extra pixels that may be drawn
+        if the edge does not lie exactly on a device pixel boundary (after being
+        transformed by the current matrix).
+    */
+    enum EdgeType {
+        /** Treat the edges as B&W (not antialiased) for the purposes of testing
+            against the current clip
+        */
+        kBW_EdgeType,
+        /** Treat the edges as antialiased for the purposes of testing
+            against the current clip
+        */
+        kAA_EdgeType
+    };
+
+    /** Return true if the specified rectangle, after being transformed by the
+        current matrix, would lie completely outside of the current clip. Call
+        this to check if an area you intend to draw into is clipped out (and
+        therefore you can skip making the draw calls).
+        @param rect the rect to compare with the current clip
+        @param et  specifies how to treat the edges (see EdgeType)
+        @return true if the rect (transformed by the canvas' matrix) does not
+                     intersect with the canvas' clip
+    */
+    bool quickReject(const SkRect& rect, EdgeType et) const;
+
+    /** Return true if the specified path, after being transformed by the
+        current matrix, would lie completely outside of the current clip. Call
+        this to check if an area you intend to draw into is clipped out (and
+        therefore you can skip making the draw calls). Note, for speed it may
+        return false even if the path itself might not intersect the clip
+        (i.e. the bounds of the path intersects, but the path does not).
+        @param path The path to compare with the current clip
+        @param et  specifies how to treat the edges (see EdgeType)
+        @return true if the path (transformed by the canvas' matrix) does not
+                     intersect with the canvas' clip
+    */
+    bool quickReject(const SkPath& path, EdgeType et) const;
+
+    /** Return true if the horizontal band specified by top and bottom is
+        completely clipped out. This is a conservative calculation, meaning
+        that it is possible that if the method returns false, the band may still
+        in fact be clipped out, but the converse is not true. If this method
+        returns true, then the band is guaranteed to be clipped out.
+        @param top  The top of the horizontal band to compare with the clip
+        @param bottom The bottom of the horizontal and to compare with the clip
+        @return true if the horizontal band is completely clipped out (i.e. does
+                     not intersect the current clip)
+    */
+    bool quickRejectY(SkScalar top, SkScalar bottom, EdgeType et) const;
+
+    /** Return the bounds of the current clip (in local coordinates) in the
+        bounds parameter, and return true if it is non-empty. This can be useful
+        in a way similar to quickReject, in that it tells you that drawing
+        outside of these bounds will be clipped out.
+    */
+    bool getClipBounds(SkRect* bounds, EdgeType et = kAA_EdgeType) const;
+
+    /** Fill the entire canvas' bitmap (restricted to the current clip) with the
+        specified ARGB color, using the specified PorterDuff mode.
+        @param a    the alpha component (0..255) of the color to fill the canvas
+        @param r    the red component (0..255) of the color to fill the canvas
+        @param g    the green component (0..255) of the color to fill the canvas
+        @param b    the blue component (0..255) of the color to fill the canvas
+        @param mode the mode to apply the color in (defaults to SrcOver)
+    */
+    void drawARGB(U8CPU a, U8CPU r, U8CPU g, U8CPU b,
+                  SkPorterDuff::Mode mode = SkPorterDuff::kSrcOver_Mode);
+
+    /** Fill the entire canvas' bitmap (restricted to the current clip) with the
+        specified color and porter-duff xfermode.
+        @param color    the color to draw with
+        @param mode the mode to apply the color in (defaults to SrcOver)
+    */
+    void drawColor(SkColor color,
+                   SkPorterDuff::Mode mode = SkPorterDuff::kSrcOver_Mode);
+
+    /** Fill the entire canvas' bitmap (restricted to the current clip) with the
+        specified paint.
+        @param paint    The paint used to fill the canvas
+    */
+    virtual void drawPaint(const SkPaint& paint);
+
+    enum PointMode {
+        /** drawPoints draws each point separately */
+        kPoints_PointMode,
+        /** drawPoints draws each pair of points as a line segment */
+        kLines_PointMode,
+        /** drawPoints draws the array of points as a polygon */
+        kPolygon_PointMode
+    };
+
+    /** Draw a series of points, interpreted based on the PointMode mode. For
+        all modes, the count parameter is interpreted as the total number of
+        points. For kLine mode, count/2 line segments are drawn.
+        For kPoint mode, each point is drawn centered at its coordinate, and its
+        size is specified by the paint's stroke-width. It draws as a square,
+        unless the paint's cap-type is round, in which the points are drawn as
+        circles.
+        For kLine mode, each pair of points is drawn as a line segment,
+        respecting the paint's settings for cap/join/width.
+        For kPolygon mode, the entire array is drawn as a series of connected
+        line segments.
+        Note that, while similar, kLine and kPolygon modes draw slightly
+        differently than the equivalent path built with a series of moveto,
+        lineto calls, in that the path will draw all of its contours at once,
+        with no interactions if contours intersect each other (think XOR
+        xfermode). drawPoints always draws each element one at a time.
+        @param mode     PointMode specifying how to draw the array of points.
+        @param count    The number of points in the array
+        @param pts      Array of points to draw
+        @param paint    The paint used to draw the points
+    */
+    virtual void drawPoints(PointMode mode, size_t count, const SkPoint pts[],
+                            const SkPaint& paint);
+
+    /** Helper method for drawing a single point. See drawPoints() for a more
+        details.
+    */
+    void drawPoint(SkScalar x, SkScalar y, const SkPaint& paint);
+    
+    /** Draws a single pixel in the specified color.
+        @param x        The X coordinate of which pixel to draw
+        @param y        The Y coordiante of which pixel to draw
+        @param color    The color to draw
+    */
+    void drawPoint(SkScalar x, SkScalar y, SkColor color);
+
+    /** Draw a line segment with the specified start and stop x,y coordinates,
+        using the specified paint. NOTE: since a line is always "framed", the
+        paint's Style is ignored.
+        @param x0    The x-coordinate of the start point of the line
+        @param y0    The y-coordinate of the start point of the line
+        @param x1    The x-coordinate of the end point of the line
+        @param y1    The y-coordinate of the end point of the line
+        @param paint The paint used to draw the line
+    */
+    void drawLine(SkScalar x0, SkScalar y0, SkScalar x1, SkScalar y1,
+                  const SkPaint& paint);
+
+    /** Draw the specified rectangle using the specified paint. The rectangle
+        will be filled or stroked based on the Style in the paint.
+        @param rect     The rect to be drawn
+        @param paint    The paint used to draw the rect
+    */
+    virtual void drawRect(const SkRect& rect, const SkPaint& paint);
+
+    /** Draw the specified rectangle using the specified paint. The rectangle
+        will be filled or framed based on the Style in the paint.
+        @param rect     The rect to be drawn
+        @param paint    The paint used to draw the rect
+    */
+    void drawIRect(const SkIRect& rect, const SkPaint& paint)
+    {
+        SkRect r;
+        r.set(rect);    // promotes the ints to scalars
+        this->drawRect(r, paint);
+    }
+    
+    /** Draw the specified rectangle using the specified paint. The rectangle
+        will be filled or framed based on the Style in the paint.
+        @param left     The left side of the rectangle to be drawn
+        @param top      The top side of the rectangle to be drawn
+        @param right    The right side of the rectangle to be drawn
+        @param bottom   The bottom side of the rectangle to be drawn
+        @param paint    The paint used to draw the rect
+    */
+    void drawRectCoords(SkScalar left, SkScalar top, SkScalar right,
+                        SkScalar bottom, const SkPaint& paint);
+
+    /** Draw the specified oval using the specified paint. The oval will be
+        filled or framed based on the Style in the paint.
+        @param oval     The rectangle bounds of the oval to be drawn
+        @param paint    The paint used to draw the oval
+    */
+    void drawOval(const SkRect& oval, const SkPaint&);
+
+    /** Draw the specified circle using the specified paint. If radius is <= 0,
+        then nothing will be drawn. The circle will be filled
+        or framed based on the Style in the paint.
+        @param cx       The x-coordinate of the center of the cirle to be drawn
+        @param cy       The y-coordinate of the center of the cirle to be drawn
+        @param radius   The radius of the cirle to be drawn
+        @param paint    The paint used to draw the circle
+    */
+    void drawCircle(SkScalar cx, SkScalar cy, SkScalar radius,
+                    const SkPaint& paint);
+
+    /** Draw the specified arc, which will be scaled to fit inside the
+        specified oval. If the sweep angle is >= 360, then the oval is drawn
+        completely. Note that this differs slightly from SkPath::arcTo, which
+        treats the sweep angle mod 360.
+        @param oval The bounds of oval used to define the shape of the arc
+        @param startAngle Starting angle (in degrees) where the arc begins
+        @param sweepAngle Sweep angle (in degrees) measured clockwise
+        @param useCenter true means include the center of the oval. For filling
+                         this will draw a wedge. False means just use the arc.
+        @param paint    The paint used to draw the arc
+    */
+    void drawArc(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle,
+                 bool useCenter, const SkPaint& paint);
+
+    /** Draw the specified round-rect using the specified paint. The round-rect
+        will be filled or framed based on the Style in the paint.
+        @param rect     The rectangular bounds of the roundRect to be drawn
+        @param rx       The x-radius of the oval used to round the corners
+        @param ry       The y-radius of the oval used to round the corners
+        @param paint    The paint used to draw the roundRect
+    */
+    void drawRoundRect(const SkRect& rect, SkScalar rx, SkScalar ry,
+                       const SkPaint& paint);
+
+    /** Draw the specified path using the specified paint. The path will be
+        filled or framed based on the Style in the paint.
+        @param path     The path to be drawn
+        @param paint    The paint used to draw the path
+    */
+    virtual void drawPath(const SkPath& path, const SkPaint& paint);
+
+    /** Draw the specified bitmap, with its top/left corner at (x,y), using the
+        specified paint, transformed by the current matrix. Note: if the paint
+        contains a maskfilter that generates a mask which extends beyond the
+        bitmap's original width/height, then the bitmap will be drawn as if it
+        were in a Shader with CLAMP mode. Thus the color outside of the original
+        width/height will be the edge color replicated.
+        @param bitmap   The bitmap to be drawn
+        @param left     The position of the left side of the bitmap being drawn
+        @param top      The position of the top side of the bitmap being drawn
+        @param paint    The paint used to draw the bitmap, or NULL
+    */
+    virtual void drawBitmap(const SkBitmap& bitmap, SkScalar left, SkScalar top,
+                            const SkPaint* paint = NULL);
+
+    /** Draw the specified bitmap, with the specified matrix applied (before the
+        canvas' matrix is applied).
+        @param bitmap   The bitmap to be drawn
+        @param src      Optional: specify the subset of the bitmap to be drawn
+        @param dst      The destination rectangle where the scaled/translated
+                        image will be drawn
+        @param paint    The paint used to draw the bitmap, or NULL
+    */
+    virtual void drawBitmapRect(const SkBitmap& bitmap, const SkIRect* src,
+                                const SkRect& dst, const SkPaint* paint = NULL);
+
+    virtual void drawBitmapMatrix(const SkBitmap& bitmap, const SkMatrix& m,
+                                  const SkPaint* paint = NULL);
+    
+    /** Draw the specified bitmap, with its top/left corner at (x,y),
+        NOT transformed by the current matrix. Note: if the paint
+        contains a maskfilter that generates a mask which extends beyond the
+        bitmap's original width/height, then the bitmap will be drawn as if it
+        were in a Shader with CLAMP mode. Thus the color outside of the original
+        width/height will be the edge color replicated.
+        @param bitmap   The bitmap to be drawn
+        @param left     The position of the left side of the bitmap being drawn
+        @param top      The position of the top side of the bitmap being drawn
+        @param paint    The paint used to draw the bitmap, or NULL
+    */
+    virtual void drawSprite(const SkBitmap& bitmap, int left, int top,
+                            const SkPaint* paint = NULL);
+
+    /** Draw the text, with origin at (x,y), using the specified paint.
+        The origin is interpreted based on the Align setting in the paint.
+        @param text The text to be drawn
+        @param byteLength   The number of bytes to read from the text parameter
+        @param x        The x-coordinate of the origin of the text being drawn
+        @param y        The y-coordinate of the origin of the text being drawn
+        @param paint    The paint used for the text (e.g. color, size, style)
+    */
+    virtual void drawText(const void* text, size_t byteLength, SkScalar x,
+                          SkScalar y, const SkPaint& paint);
+
+    /** Draw the text, with each character/glyph origin specified by the pos[]
+        array. The origin is interpreted by the Align setting in the paint. 
+        @param text The text to be drawn
+        @param byteLength   The number of bytes to read from the text parameter
+        @param pos      Array of positions, used to position each character
+        @param paint    The paint used for the text (e.g. color, size, style)
+        */
+    virtual void drawPosText(const void* text, size_t byteLength,
+                             const SkPoint pos[], const SkPaint& paint);
+    
+    /** Draw the text, with each character/glyph origin specified by the x
+        coordinate taken from the xpos[] array, and the y from the constY param.
+        The origin is interpreted by the Align setting in the paint. 
+        @param text The text to be drawn
+        @param byteLength   The number of bytes to read from the text parameter
+        @param xpos     Array of x-positions, used to position each character
+        @param constY   The shared Y coordinate for all of the positions
+        @param paint    The paint used for the text (e.g. color, size, style)
+        */
+    virtual void drawPosTextH(const void* text, size_t byteLength,
+                              const SkScalar xpos[], SkScalar constY,
+                              const SkPaint& paint);
+    
+    /** Draw the text, with origin at (x,y), using the specified paint, along
+        the specified path. The paint's Align setting determins where along the
+        path to start the text.
+        @param text The text to be drawn
+        @param byteLength   The number of bytes to read from the text parameter
+        @param path         The path the text should follow for its baseline
+        @param hOffset      The distance along the path to add to the text's
+                            starting position
+        @param vOffset      The distance above(-) or below(+) the path to
+                            position the text
+        @param paint        The paint used for the text
+    */
+    void drawTextOnPathHV(const void* text, size_t byteLength,
+                          const SkPath& path, SkScalar hOffset,
+                          SkScalar vOffset, const SkPaint& paint);
+
+    /** Draw the text, with origin at (x,y), using the specified paint, along
+        the specified path. The paint's Align setting determins where along the
+        path to start the text.
+        @param text The text to be drawn
+        @param byteLength   The number of bytes to read from the text parameter
+        @param path         The path the text should follow for its baseline
+        @param matrix       (may be null) Applied to the text before it is
+                            mapped onto the path
+        @param paint        The paint used for the text
+        */
+    virtual void drawTextOnPath(const void* text, size_t byteLength,
+                                const SkPath& path, const SkMatrix* matrix,
+                                const SkPaint& paint);
+
+    /** Draw the picture into this canvas. This method effective brackets the
+        playback of the picture's draw calls with save/restore, so the state
+        of this canvas will be unchanged after this call. This contrasts with
+        the more immediate method SkPicture::draw(), which does not bracket
+        the canvas with save/restore, thus the canvas may be left in a changed
+        state after the call.
+        @param picture The recorded drawing commands to playback into this
+                       canvas.
+    */
+    virtual void drawPicture(SkPicture& picture);
+    
+    enum VertexMode {
+        kTriangles_VertexMode,
+        kTriangleStrip_VertexMode,
+        kTriangleFan_VertexMode
+    };
+    
+    /** Draw the array of vertices, interpreted as triangles (based on mode).
+        @param vmode How to interpret the array of vertices
+        @param vertexCount The number of points in the vertices array (and
+                    corresponding texs and colors arrays if non-null)
+        @param vertices Array of vertices for the mesh
+        @param texs May be null. If not null, specifies the coordinate
+                             in texture space for each vertex.
+        @param colors May be null. If not null, specifies a color for each
+                      vertex, to be interpolated across the triangle.
+        @param xmode Used if both texs and colors are present. In this
+                    case the colors are combined with the texture using mode,
+                    before being drawn using the paint. If mode is null, then
+                    the porter-duff MULTIPLY mode is used.
+        @param indices If not null, array of indices to reference into the
+                    vertex (texs, colors) array.
+        @param indexCount number of entries in the indices array (if not null)
+        @param paint Specifies the shader/texture if present. 
+    */
+    virtual void drawVertices(VertexMode vmode, int vertexCount,
+                              const SkPoint vertices[], const SkPoint texs[],
+                              const SkColor colors[], SkXfermode* xmode,
+                              const uint16_t indices[], int indexCount,
+                              const SkPaint& paint);
+
+    //////////////////////////////////////////////////////////////////////////
+    
+    /** Get the current bounder object.
+        The bounder's reference count is unchaged.
+        @return the canva's bounder (or NULL).
+    */
+    SkBounder*  getBounder() const { return fBounder; }
+
+    /** Set a new bounder (or NULL).
+        Pass NULL to clear any previous bounder.
+        As a convenience, the parameter passed is also returned.
+        If a previous bounder exists, its reference count is decremented.
+        If bounder is not NULL, its reference count is incremented.
+        @param bounder the new bounder (or NULL) to be installed in the canvas
+        @return the set bounder object
+    */
+    virtual SkBounder* setBounder(SkBounder* bounder);
+ 
+    /** Get the current filter object. The filter's reference count is not
+        affected. The filter is part of the state this is affected by
+        save/restore.
+        @return the canvas' filter (or NULL).
+    */
+    SkDrawFilter* getDrawFilter() const;
+    
+    /** Set the new filter (or NULL). Pass NULL to clear any existing filter.
+        As a convenience, the parameter is returned. If an existing filter
+        exists, its refcnt is decrement. If the new filter is not null, its
+        refcnt is incremented. The filter is part of the state this is affected
+        by save/restore.
+        @param filter the new filter (or NULL)
+        @return the new filter
+    */
+    virtual SkDrawFilter* setDrawFilter(SkDrawFilter* filter);
+
+    //////////////////////////////////////////////////////////////////////////
+
+    /** Return the current matrix on the canvas.
+        This does not account for the translate in any of the devices.
+        @return The current matrix on the canvas.
+    */
+    const SkMatrix& getTotalMatrix() const;
+
+    /** Return the current device clip (concatenation of all clip calls).
+        This does not account for the translate in any of the devices.
+        @return the current device clip (concatenation of all clip calls).
+    */
+    const SkRegion& getTotalClip() const;
+
+    /** May be overridden by subclasses. This returns a compatible device
+        for this canvas, with the specified config/width/height. If isOpaque
+        is true, then the underlying bitmap is optimized to assume that every
+        pixel will be drawn to, and thus it does not need to clear the alpha
+        channel ahead of time (assuming the specified config supports per-pixel
+        alpha.) If isOpaque is false, then the bitmap should clear its alpha
+        channel.
+    */
+    virtual SkDevice* createDevice(SkBitmap::Config, int width, int height,
+                                   bool isOpaque, bool isForLayer);
+
+    ///////////////////////////////////////////////////////////////////////////
+
+    /** After calling saveLayer(), there can be any number of devices that make
+        up the top-most drawing area. LayerIter can be used to iterate through
+        those devices. Note that the iterator is only valid until the next API
+        call made on the canvas. Ownership of all pointers in the iterator stays
+        with the canvas, so none of them should be modified or deleted.
+    */
+    class LayerIter /*: SkNoncopyable*/ {
+    public:
+        /** Initialize iterator with canvas, and set values for 1st device */
+        LayerIter(SkCanvas*, bool skipEmptyClips);
+        ~LayerIter();
+        
+        /** Return true if the iterator is done */
+        bool done() const { return fDone; }
+        /** Cycle to the next device */
+        void next();
+        
+        // These reflect the current device in the iterator
+
+        SkDevice*       device() const;
+        const SkMatrix& matrix() const;
+        const SkRegion& clip() const;
+        const SkPaint&  paint() const;
+        int             x() const;
+        int             y() const;
+        
+    private:
+        // used to embed the SkDrawIter object directly in our instance, w/o
+        // having to expose that class def to the public. There is an assert
+        // in our constructor to ensure that fStorage is large enough
+        // (though needs to be a compile-time-assert!). We use intptr_t to work
+        // safely with 32 and 64 bit machines (to ensure the storage is enough)
+        intptr_t          fStorage[12];
+        class SkDrawIter* fImpl;    // this points at fStorage
+        SkPaint           fDefaultPaint;
+        bool              fDone;
+    };
+
+protected:
+    // all of the drawBitmap variants call this guy
+    virtual void commonDrawBitmap(const SkBitmap&, const SkMatrix& m,
+                                  const SkPaint& paint);
+    
+private:
+    class MCRec;
+
+    SkDeque     fMCStack;
+    // points to top of stack
+    MCRec*      fMCRec;
+    // the first N recs that can fit here mean we won't call malloc
+    uint32_t    fMCRecStorage[32];
+
+    SkBounder*  fBounder;
+
+    void prepareForDeviceDraw(SkDevice*);
+    
+    bool fDeviceCMDirty;            // cleared by updateDeviceCMCache()
+    void updateDeviceCMCache();
+
+    friend class SkDrawIter;    // needs setupDrawForLayerDevice()
+
+    SkDevice* init(SkDevice*);
+    void internalDrawBitmap(const SkBitmap&, const SkMatrix& m,
+                                  const SkPaint* paint);
+    void drawDevice(SkDevice*, int x, int y, const SkPaint*);
+    // shared by save() and saveLayer()
+    int internalSave(SaveFlags flags);
+    void internalRestore();
+    
+    /*  These maintain a cache of the clip bounds in local coordinates,
+        (converted to 2s-compliment if floats are slow).
+     */
+    mutable SkRectCompareType fLocalBoundsCompareType;
+    mutable bool              fLocalBoundsCompareTypeDirty;
+
+    const SkRectCompareType& getLocalClipBoundsCompareType() const {
+        if (fLocalBoundsCompareTypeDirty) {
+            this->computeLocalClipBoundsCompareType();
+            fLocalBoundsCompareTypeDirty = false;
+        }
+        return fLocalBoundsCompareType;
+    }
+    void computeLocalClipBoundsCompareType() const;
+};
+
+/** Stack helper class to automatically call restoreToCount() on the canvas
+    when this object goes out of scope. Use this to guarantee that the canvas
+    is restored to a known state.
+*/
+class SkAutoCanvasRestore : SkNoncopyable {
+public:
+    SkAutoCanvasRestore(SkCanvas* canvas, bool doSave) : fCanvas(canvas) {
+        SkASSERT(canvas);
+        fSaveCount = canvas->getSaveCount();
+        if (doSave) {
+            canvas->save();
+        }
+    }
+    ~SkAutoCanvasRestore() {
+        fCanvas->restoreToCount(fSaveCount);
+    }
+
+private:
+    SkCanvas*   fCanvas;
+    int         fSaveCount;
+};
+
+#endif
+