Added drawPosTextOnPath method.

The drawPosTextOnPath method allows for text positioned on
a straight line to be drawn along a path.
This method can be used by layout engines to implement the
Canvas::drawTextOnPath method for complex scripts.

Change-Id: I2f9c22b8c97eeacb61cd6de7429ba875a1e7ade9

3 files changed, 19 insertions, 0 deletions

diff --git a/include/core/SkCanvas.h b/include/core/SkCanvas.h
index 8fba6cf..f88a8b9 100644
--- a/include/core/SkCanvas.h
+++ b/include/core/SkCanvas.h
@@ -581,6 +581,19 @@ public:
                                 const SkPath& path, const SkMatrix* matrix,
                                 const SkPaint& paint);
 
+    /** Draw the text on path, 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)
+        @param path The path to draw on
+        @param matrix The canvas matrix
+        */
+    void drawPosTextOnPath(const void* text, size_t byteLength,
+                           const SkPoint pos[], const SkPaint& paint,
+                           const SkPath& path, const SkMatrix* matrix);
+
     /** 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
diff --git a/include/core/SkDevice.h b/include/core/SkDevice.h
index 4d678c6..0d724ba 100644
--- a/include/core/SkDevice.h
+++ b/include/core/SkDevice.h
@@ -120,6 +120,9 @@ public:
     virtual void drawTextOnPath(const SkDraw&, const void* text, size_t len,
                                 const SkPath& path, const SkMatrix* matrix,
                                 const SkPaint& paint);
+    virtual void drawPosTextOnPath(const SkDraw& draw, const void* text, size_t len,
+                                   const SkPoint pos[], const SkPaint& paint,
+                                   const SkPath& path, const SkMatrix* matrix);
     virtual void drawVertices(const SkDraw&, SkCanvas::VertexMode, int vertexCount,
                               const SkPoint verts[], const SkPoint texs[],
                               const SkColor colors[], SkXfermode* xmode,
diff --git a/include/core/SkDraw.h b/include/core/SkDraw.h
index 8214859..a86ef67 100644
--- a/include/core/SkDraw.h
+++ b/include/core/SkDraw.h
@@ -54,6 +54,9 @@ public:
                         int scalarsPerPosition, const SkPaint& paint) const;
     void    drawTextOnPath(const char text[], size_t byteLength,
                         const SkPath&, const SkMatrix*, const SkPaint&) const;
+    void    drawPosTextOnPath(const char text[], size_t byteLength,
+                              const SkPoint pos[], const SkPaint& paint,
+                              const SkPath& path, const SkMatrix* matrix) const;
     void    drawVertices(SkCanvas::VertexMode mode, int count,
                          const SkPoint vertices[], const SkPoint textures[],
                          const SkColor colors[], SkXfermode* xmode,