Bmp Image Decoding

src/codec/SkMaskSwizzler.h

Index: src/codec/SkMaskSwizzler.h
diff --git a/src/codec/SkMaskSwizzler.h b/src/codec/SkMaskSwizzler.h
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index 0000000000000000000000000000000000000000..9351f0228ba2a771e418a768752ed71b1bbf750b
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+++ b/src/codec/SkMaskSwizzler.h
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+/*
+ * 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 "SkMasks.h"
+#include "SkSwizzler.h"
+#include "SkTypes.h"
+
+/*
+ *
+ * Used to swizzle images whose pixel components are extracted by bit masks
+ * Currently only used by bmp
+ *
+ */
+class SkMaskSwizzler {
+public:
+
+    /*
+     *
+     * Create a new swizzler
+     * @param masks Unowned pointer to helper class
+     *
+     */
+    static SkMaskSwizzler* CreateMaskSwizzler(const SkImageInfo& imageInfo,
+                                              SkMasks* masks,
+                                              uint32_t bitsPerPixel);
+
+    /*
+     *
+     * Swizzle the next row
+     *
+     */
+    SkSwizzler::ResultAlpha next(void* dst, const uint8_t* src);
+
+private:
+
+    /*
+     *
+     * Row procedure used for swizzle
+     *
+     */
+    typedef SkSwizzler::ResultAlpha (*RowProc)(
+            void* dstRow, const uint8_t* srcRow, int width,
+            SkMasks* masks);
+
+    /*
+     *
+     * Constructor for mask swizzler
+     *
+     */
+    SkMaskSwizzler(const SkImageInfo& info, SkMasks* masks, RowProc proc);
+
+    // Fields
+    const SkImageInfo& fImageInfo;
+    SkMasks*           fMasks;     // unowned
+    const RowProc      fRowProc;
+};