SkScaledCodec class

include/codec/SkScaledCodec.h

Index: include/codec/SkScaledCodec.h
diff --git a/include/codec/SkScaledCodec.h b/include/codec/SkScaledCodec.h
new file mode 100644
index 0000000000000000000000000000000000000000..d71101a24c6963ab237dbbaa620b8ab57d192257
--- /dev/null
+++ b/include/codec/SkScaledCodec.h
@@ -0,0 +1,54 @@
+/*
+ * 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 "SkCodec.h"
+#include "SkColorTable.h"
+#include "SkEncodedFormat.h"
+#include "SkImageInfo.h"
+#include "SkRefCnt.h"
+#include "SkSwizzler.h"
+#include "SkCodec_libpng.h"
+#include "SkScanlineDecoder.h"
+
+class SkScanlineDecoder;
+class SkStream;
+
+class SkScaledCodec : public SkCodec {
+public:
+	static SkCodec* NewFromStream(SkStream*);

[scroggo, 2015/07/27 15:09:19]

This (and other functions) should be indented four characters, rather than
eight.

[emmaleer, 2015/07/27 18:31:38]

Acknowledged.

+	static SkCodec* NewFromData(SkData*);
+
+    virtual ~SkScaledCodec();
+
+protected:
+	// Recommend a set of destination dimensions given a requested scale
+    SkISize onGetScaledDimensions(float desiredScale) const override;
+
+	Result onGetPixels(const SkImageInfo&, void*, size_t, const Options&, SkPMColor*, int*)
+        	override;
+    SkEncodedFormat onGetEncodedFormat() const override{
+    	return fCodec->getEncodedFormat();
+    }
+
+    SkScanlineDecoder* onGetScanlineDecoder(const SkImageInfo& dstInfo, const Options& options,
+                                            SkPMColor ctable[], int* ctableCount) override{
+    	return fCodec->getScanlineDecoder(dstInfo, &options, ctable, ctableCount);
+    }
+    bool onReallyHasAlpha() const override{
+    	return fCodec->reallyHasAlpha();
+    }
+
+private:
+	SkAutoTDelete<SkCodec>   fCodec;

[scroggo, 2015/07/27 15:09:19]

These fields should also be indented only four characters.

[emmaleer, 2015/07/27 18:31:38]

Acknowledged.

+	int                      fSampleY;   // step between Y samples. Is constant

[scroggo, 2015/07/27 15:09:19]

These variables do not appear to be const.

They are set each time onGetPixels is called.

Therefore, they do not even need to be member variables. You can just declare
them inside onGetPixels. (In that case, they *can* be const, since they will be
const for their entire lifetimes - the rest of the function they are in.)

[emmaleer, 2015/07/27 18:31:38]

Acknowledged.

+	int                 	 fY0;        // first Y coord (scanline) to sample. Is constant
+
+    SkScaledCodec(SkCodec*);
+
+
+    typedef SkCodec INHERITED;
+};