Add skia to the repository.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@16 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 115 insertions, 0 deletions

diff --git a/skia/include/SkXfermode.h b/skia/include/SkXfermode.h
new file mode 100644
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+++ b/skia/include/SkXfermode.h
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+/*
+ * Copyright (C) 2006 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 SkXfermode_DEFINED
+#define SkXfermode_DEFINED
+
+#include "SkFlattenable.h"
+#include "SkColor.h"
+
+/** \class SkXfermode
+
+    SkXfermode is the base class for objects that are called to implement custom
+    "transfer-modes" in the drawing pipeline. The static function Create(Modes)
+    can be called to return an instance of any of the predefined subclasses as
+    specified in the Modes enum. When an SkXfermode is assigned to an SkPaint,
+    then objects drawn with that paint have the xfermode applied.
+*/
+class SkXfermode : public SkFlattenable {
+public:
+    SkXfermode() {}
+
+    virtual void xfer32(SkPMColor dst[], const SkPMColor src[], int count,
+                        const SkAlpha aa[]);
+    virtual void xfer16(uint16_t dst[], const SkPMColor src[], int count,
+                        const SkAlpha aa[]);
+    virtual void xfer4444(uint16_t dst[], const SkPMColor src[], int count,
+                          const SkAlpha aa[]);
+    virtual void xferA8(SkAlpha dst[], const SkPMColor src[], int count,
+                        const SkAlpha aa[]);
+    
+    enum Coeff {
+        kZero_Coeff,
+        kOne_Coeff,
+        kSC_Coeff,
+        kISC_Coeff,
+        kDC_Coeff,
+        kIDC_Coeff,
+        kSA_Coeff,
+        kISA_Coeff,
+        kDA_Coeff,
+        kIDA_Coeff,
+        
+        kCoeffCount
+    };
+    virtual bool asCoeff(Coeff* src, Coeff* dst);
+
+protected:
+    SkXfermode(SkFlattenableReadBuffer& rb) : SkFlattenable(rb) {}
+    
+    /** The default implementation of xfer32/xfer16/xferA8 in turn call this
+        method, 1 color at a time (upscaled to a SkPMColor). The default
+        implmentation of this method just returns dst. If performance is
+        important, your subclass should override xfer32/xfer16/xferA8 directly.
+        
+        This method will not be called directly by the client, so it need not
+        be implemented if your subclass has overridden xfer32/xfer16/xferA8
+    */
+    virtual SkPMColor xferColor(SkPMColor src, SkPMColor dst);
+
+private:
+    typedef SkFlattenable INHERITED;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+/** \class SkProcXfermode
+
+    SkProcXfermode is a xfermode that applies the specified proc to its colors.
+    This class is not exported to java.
+*/
+class SkProcXfermode : public SkXfermode {
+public:
+    SkProcXfermode(SkXfermodeProc proc) : fProc(proc) {}
+
+    // overrides from SkXfermode
+    virtual void xfer32(SkPMColor dst[], const SkPMColor src[], int count,
+                        const SkAlpha aa[]);
+    virtual void xfer16(uint16_t dst[], const SkPMColor src[], int count,
+                        const SkAlpha aa[]);
+    virtual void xfer4444(uint16_t dst[], const SkPMColor src[], int count,
+                          const SkAlpha aa[]);
+    virtual void xferA8(SkAlpha dst[], const SkPMColor src[], int count,
+                        const SkAlpha aa[]);
+
+    // overrides from SkFlattenable
+    virtual Factory getFactory() { return CreateProc; }
+    virtual void    flatten(SkFlattenableWriteBuffer&);
+
+protected:
+    SkProcXfermode(SkFlattenableReadBuffer&);
+
+private:
+    SkXfermodeProc  fProc;
+    
+    static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) {
+        return SkNEW_ARGS(SkProcXfermode, (buffer)); }
+
+    typedef SkXfermode INHERITED;
+};
+
+#endif
+