SkCanvas interface for drawing a patch.

src/core/SkBitmapDevice.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapDevice.h"
 #include "SkConfig8888.h"
 #include "SkDraw.h"
@@ skipping 325 matching lines @@
 void SkBitmapDevice::drawVertices(const SkDraw& draw, SkCanvas::VertexMode vmode,
                                   int vertexCount,
                                   const SkPoint verts[], const SkPoint textures[],
                                   const SkColor colors[], SkXfermode* xmode,
                                   const uint16_t indices[], int indexCount,
                                   const SkPaint& paint) {
     draw.drawVertices(vmode, vertexCount, verts, textures, colors, xmode,
                       indices, indexCount, paint);
 }
 
+void SkBitmapDevice::drawPatch(const SkDraw& draw, const SkPatch& patch, const SkPaint& paint) {
+    SkPatch::VertexData data;
+    patch.getVertexData(&data, draw.fMatrix->getScaleX() * 10, draw.fMatrix->getScaleY() * 10);

[bsalomon, 2014/07/28 20:56:26]

I don't think getScaleX and getScaleY are what you want. I think that will give
you 0 for this matrix:

0   100 0
100   0 0
0     0 1

You might want SkMatrix::getMaxScale().

The 10x scale factor should have some kind of comment. Does the tess. level not
depend on the size of the patch?

This implementation could be in SkDevice and then all the other subclasses can
share it (until they have their own specializations where it makes sense to do
so).

[dandov, 2014/07/29 18:45:46]

I moved this to SkBaseDevice and created a default implementation, the level of
detail now takes into account the size of the patch using its corner points
already mapped to the transform matrix in SkDraw. 

+    draw.drawVertices(SkCanvas::kTriangles_VertexMode, data.fVertexCount, data.fPoints,
+                      data.fTexCoords, data.fColors, NULL, data.fIndices, data.fIndexCount, paint);
+}
+
 void SkBitmapDevice::drawDevice(const SkDraw& draw, SkBaseDevice* device,
                                 int x, int y, const SkPaint& paint) {
     const SkBitmap& src = device->accessBitmap(false);
     draw.drawSprite(src, x, y, paint);
 }
 
 SkSurface* SkBitmapDevice::newSurface(const SkImageInfo& info) {
     return SkSurface::NewRaster(info);
 }
 
@@ skipping 26 matching lines @@
         paint.getStyle() != SkPaint::kFill_Style ||
         !SkXfermode::IsMode(paint.getXfermode(), SkXfermode::kSrcOver_Mode)) {
         // turn off lcd
         flags->fFlags = paint.getFlags() & ~SkPaint::kLCDRenderText_Flag;
         flags->fHinting = paint.getHinting();
         return true;
     }
     // we're cool with the paint as is
     return false;
 }