add Method param to drawTextOnPath, supporting SVG spec

include/core/SkCanvas.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 SkCanvas_DEFINED
 #define SkCanvas_DEFINED
 
 #include "SkTypes.h"
 #include "SkBitmap.h"
 #include "SkDeque.h"
 #include "SkClipStack.h"
 #include "SkPaint.h"
 #include "SkRefCnt.h"
 #include "SkPath.h"
 #include "SkRegion.h"
 #include "SkSurfaceProps.h"
 #include "SkXfermode.h"
 
+#ifdef SK_SUPPORT_LEGACY_DRAWTEXTONPATH
+    #define SK_SUPPORT_LEGACY_DRAWTEXTONPATH_PARAM
+    #define SK_SUPPORT_LEGACY_DRAWTEXTONPATH_ARG
+    #define SK_SUPPORT_LEGACY_DRAWTEXTONPATH_DEFAULT_METHOD \
+        SkCanvas::TextOnPathMethod method = SkCanvas::kStretch_TextOnPathMethod;
+#else
+    #define SK_SUPPORT_LEGACY_DRAWTEXTONPATH_PARAM          SkCanvas::TextOnPathMethod method,
+    #define SK_SUPPORT_LEGACY_DRAWTEXTONPATH_ARG            method,
+    #define SK_SUPPORT_LEGACY_DRAWTEXTONPATH_DEFAULT_METHOD
+#endif
+
 class SkBaseDevice;
 class SkCanvasClipVisitor;
 class SkDraw;
 class SkDrawable;
 class SkDrawFilter;
 class SkImage;
 class SkMetaData;
 class SkPicture;
 class SkRRect;
 class SkSurface;
@@ skipping 870 matching lines @@
         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)
         */
     void drawPosTextH(const void* text, size_t byteLength, const SkScalar xpos[], SkScalar constY,
                       const SkPaint& paint);
 
+#ifdef SK_SUPPORT_LEGACY_DRAWTEXTONPATH
     /** 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
+        @param trangentOffset The distance along the path to add to the text's
                             starting position
-        @param vOffset      The distance above(-) or below(+) the path to
+        @param normalOffset 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);
+    void drawTextOnPathHV(const void* text, size_t byteLength, const SkPath& path,
+                          SkScalar trangentOffset, SkScalar normalOffset, 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
         */
     void drawTextOnPath(const void* text, size_t byteLength, const SkPath& path,
                         const SkMatrix* matrix, const SkPaint& paint);
+#endif
+
+    enum TextOnPathMethod {
+        kStretch_TextOnPathMethod,  //!< warp the shape of each glyph to match the path
+        kAlign_TextOnPathMethod     //!< rotate each glyph to align with the path's direction
+    };
+
+    /**
+     *  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 method       How to orient/warp each glyph along the path.
+     *  @param paint        The paint used for the text
+     */
+    void drawTextOnPath(const void* text, size_t byteLength, const SkPath& path,
+                        const SkMatrix* matrix, TextOnPathMethod, const SkPaint& paint);
 
     /** Draw the text blob, offset by (x,y), using the specified paint.
         @param blob     The text blob to be drawn
         @param x        The x-offset of the text being drawn
         @param y        The y-offset of the text being drawn
         @param paint    The paint used for the text (e.g. color, size, style)
     */
     void drawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y, const SkPaint& paint);
 
     /** Draw the picture into this canvas. This method effective brackets the
@@ skipping 232 matching lines @@
 
     virtual void onDrawPosText(const void* text, size_t byteLength,
                                const SkPoint pos[], const SkPaint& paint);
 
     virtual void onDrawPosTextH(const void* text, size_t byteLength,
                                 const SkScalar xpos[], SkScalar constY,
                                 const SkPaint& paint);
 
     virtual void onDrawTextOnPath(const void* text, size_t byteLength,
                                   const SkPath& path, const SkMatrix* matrix,
+                                  SK_SUPPORT_LEGACY_DRAWTEXTONPATH_PARAM
                                   const SkPaint& paint);
 
     virtual void onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y,
                                 const SkPaint& paint);
 
     virtual void onDrawPatch(const SkPoint cubics[12], const SkColor colors[4],
                            const SkPoint texCoords[4], SkXfermode* xmode, const SkPaint& paint);
 
     virtual void onDrawDrawable(SkDrawable*);
 
@@ skipping 299 matching lines @@
 
 class SkCanvasClipVisitor {
 public:
     virtual ~SkCanvasClipVisitor();
     virtual void clipRect(const SkRect&, SkRegion::Op, bool antialias) = 0;
     virtual void clipRRect(const SkRRect&, SkRegion::Op, bool antialias) = 0;
     virtual void clipPath(const SkPath&, SkRegion::Op, bool antialias) = 0;
 };
 
 #endif