This CL implements a tesselated path renderer, using GLU's libtess. All of the

fill modes except hairline are supported.  Note that the path renderer is not
enabled by default; to enable it, replace "GrCreatePathRenderer_none.cpp" with
"GrCreatePathRenderer_tesselated.cpp" in skia.gyp, and run gyp_skia, and build.

This change also contains a number of build fixes for Win32 (for building
SampleApp on VS2008) and Mac (for my ancient Mac Pro which supports
GL_EXT_framebuffer_object but not GL_ARB_framebuffer_object).  Also,
priorityq-heap.c was removed from the SampleApp build, since it's #included by
priorityq.c (weird, I know).

NB:  When this change is rolled into chrome, some modifications to chromium's
skia.gyp will be necessary.

Review URL:  http://codereview.appspot.com/4289072/



git-svn-id: http://skia.googlecode.com/svn/trunk@1012 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 52 insertions, 0 deletions

diff --git a/gpu/src/GrPathUtils.h b/gpu/src/GrPathUtils.h
new file mode 100644
index 0000000000..97841dd1e2
--- /dev/null
+++ b/gpu/src/GrPathUtils.h
@@ -0,0 +1,52 @@
+/*
+    Copyright 2011 Google Inc.
+
+    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 GrPathUtils_DEFINED
+#define GrPathUtils_DEFINED
+
+#include "GrNoncopyable.h"
+#include "GrScalar.h"
+
+class GrPathIter;
+struct GrPoint;
+
+/**
+ *  Utilities for evaluating paths.
+ */
+class GrPathUtils : public GrNoncopyable {
+public:
+    static int worstCasePointCount(GrPathIter* path,
+                                   int* subpaths,
+                                   GrScalar tol);
+    static uint32_t quadraticPointCount(const GrPoint points[], GrScalar tol);
+    static uint32_t generateQuadraticPoints(const GrPoint& p0,
+                                            const GrPoint& p1,
+                                            const GrPoint& p2,
+                                            GrScalar tolSqd,
+                                            GrPoint** points,
+                                            uint32_t pointsLeft);
+    static uint32_t cubicPointCount(const GrPoint points[], GrScalar tol);
+    static uint32_t generateCubicPoints(const GrPoint& p0,
+                                        const GrPoint& p1,
+                                        const GrPoint& p2,
+                                        const GrPoint& p3,
+                                        GrScalar tolSqd,
+                                        GrPoint** points,
+                                        uint32_t pointsLeft);
+
+    static const GrScalar gTolerance;
+};
+#endif