Add support for non-mappable vert buffers to tessellating path renderer.

src/gpu/GrTessellatingPathRenderer.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrTessellatingPathRenderer.h"
 
 #include "GrBatchFlushState.h"
@@ skipping 1399 matching lines @@
         // Handle any color overrides
         if (!opt.readsColor()) {
             fColor = GrColor_ILLEGAL;
         }
         opt.getOverrideColorIfSet(&fColor);
         fPipelineInfo = opt;
     }
 
     int tessellate(GrUniqueKey* key,
                    GrResourceProvider* resourceProvider,
-                   SkAutoTUnref<GrVertexBuffer>& vertexBuffer) {
+                   SkAutoTUnref<GrVertexBuffer>& vertexBuffer,
+                   bool canMapVB) {
         SkPath path;
         GrStrokeInfo stroke(fStroke);
         if (stroke.isDashed()) {
             if (!stroke.applyDashToPath(&path, &stroke, fPath)) {
                 return 0;
             }
         } else {
             path = fPath;
         }
         if (!stroke.isFillStyle()) {
@@ skipping 52 matching lines @@
 
         size_t size = count * sizeof(SkPoint);
         if (!vertexBuffer.get() || vertexBuffer->gpuMemorySize() < size) {
             vertexBuffer.reset(resourceProvider->createVertexBuffer(
                 size, GrResourceProvider::kStatic_BufferUsage, 0));
         }
         if (!vertexBuffer.get()) {
             SkDebugf("Could not allocate vertices\n");
             return 0;
         }
-        SkPoint* verts = static_cast<SkPoint*>(vertexBuffer->map());
-        LOG("emitting %d verts\n", count);
+        SkPoint* verts;
+        if (canMapVB) {
+            verts = static_cast<SkPoint*>(vertexBuffer->map());
+        } else {
+            verts = SkNEW_ARRAY(SkPoint, count);
+        }
         SkPoint* end = polys_to_triangles(polys, fillType, verts);
-        vertexBuffer->unmap();
         int actualCount = static_cast<int>(end - verts);
         LOG("actual count: %d\n", actualCount);
         SkASSERT(actualCount <= count);
+        if (canMapVB) {
+            vertexBuffer->unmap();
+        } else {
+            vertexBuffer->updateData(verts, actualCount * sizeof(SkPoint));
+            SkDELETE_ARRAY(verts);
+        }
+
 
         if (!fPath.isVolatile()) {
             TessInfo info;
             info.fTolerance = isLinear ? 0 : tol;
             info.fCount = actualCount;
             SkAutoTUnref<SkData> data(SkData::NewWithCopy(&info, sizeof(info)));
             key->setCustomData(data.get());
             resourceProvider->assignUniqueKeyToResource(*key, vertexBuffer.get());
             SkPathPriv::AddGenIDChangeListener(fPath, SkNEW(PathInvalidator(*key)));
         }
@@ skipping 16 matching lines @@
         }
         fStroke.asUniqueKeyFragment(&builder[2 + clipBoundsSize32]);
         builder.finish();
         GrResourceProvider* rp = target->resourceProvider();
         SkAutoTUnref<GrVertexBuffer> vertexBuffer(rp->findAndRefTByUniqueKey<GrVertexBuffer>(key));
         int actualCount;
         SkScalar screenSpaceTol = GrPathUtils::kDefaultTolerance;
         SkScalar tol = GrPathUtils::scaleToleranceToSrc(
             screenSpaceTol, fViewMatrix, fPath.getBounds());
         if (!cache_match(vertexBuffer.get(), tol, &actualCount)) {
-            actualCount = tessellate(&key, rp, vertexBuffer);
+            bool canMapVB = GrCaps::kNone_MapFlags != target->caps().mapBufferFlags();
+            actualCount = tessellate(&key, rp, vertexBuffer, canMapVB);
         }
 
         if (actualCount == 0) {
             return;
         }
 
         SkAutoTUnref<const GrGeometryProcessor> gp;
         {
             using namespace GrDefaultGeoProcFactory;
 
@@ skipping 94 matching lines @@
     bool result = viewMatrix.invert(&vmi);
     if (!result) {
         SkFAIL("Cannot invert matrix\n");
     }
     vmi.mapRect(&clipBounds);
     GrStrokeInfo strokeInfo = GrTest::TestStrokeInfo(random);
     return TessellatingPathBatch::Create(color, path, strokeInfo, viewMatrix, clipBounds);
 }
 
 #endif