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-rw-r--r--include/core/SkAutoKern.h62
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diff --git a/include/core/SkAutoKern.h b/include/core/SkAutoKern.h
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+++ b/include/core/SkAutoKern.h
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+/* libs/graphics/sgl/SkAutoKern.h
+**
+** Copyright 2006, The Android Open Source Project
+**
+** 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 SkAutoKern_DEFINED
+#define SkAutoKern_DEFINED
+
+#include "SkScalerContext.h"
+
+#define SkAutoKern_AdjustF(prev, next) (((next) - (prev) + 32) >> 6 << 16)
+#define SkAutoKern_AdjustS(prev, next) SkIntToScalar(((next) - (prev) + 32) >> 6)
+
+/* this is a helper class to perform auto-kerning
+ * the adjust() method returns a SkFixed corresponding
+ * to a +1/0/-1 pixel adjustment
+ */
+
+class SkAutoKern {
+public:
+ SkAutoKern() : fPrevRsbDelta(0) {}
+
+ SkFixed adjust(const SkGlyph& glyph)
+ {
+// if (SkAbs32(glyph.fLsbDelta) > 47 || SkAbs32(glyph.fRsbDelta) > 47)
+// printf("------- %d> L %d R %d\n", glyph.f_GlyphID, glyph.fLsbDelta, glyph.fRsbDelta);
+
+#if 0
+ int distort = fPrevRsbDelta - glyph.fLsbDelta;
+
+ fPrevRsbDelta = glyph.fRsbDelta;
+
+ if (distort >= 32)
+ return -SK_Fixed1;
+ else if (distort < -32)
+ return +SK_Fixed1;
+ else
+ return 0;
+#else
+ SkFixed adjust = SkAutoKern_AdjustF(fPrevRsbDelta, glyph.fLsbDelta);
+ fPrevRsbDelta = glyph.fRsbDelta;
+ return adjust;
+#endif
+ }
+private:
+ int fPrevRsbDelta;
+};
+
+#endif
+