Scanline decoding for bmp

src/codec/SkBmpMaskCodec.cpp

Index: src/codec/SkBmpMaskCodec.cpp
diff --git a/src/codec/SkBmpMaskCodec.cpp b/src/codec/SkBmpMaskCodec.cpp
index 7d1706e697f0e3b955a866e53d77ae65def773f4..5cc0d4b348ad519251358356275014a600069aa4 100644
--- a/src/codec/SkBmpMaskCodec.cpp
+++ b/src/codec/SkBmpMaskCodec.cpp
@@ -40,9 +40,10 @@ static bool conversion_possible(const SkImageInfo& dst,
  * Creates an instance of the decoder
  */
 SkBmpMaskCodec::SkBmpMaskCodec(const SkImageInfo& info, SkStream* stream,
+                               SkBmpCodec::BmpInputFormat inputFormat,
                                uint16_t bitsPerPixel, SkMasks* masks,
                                SkBmpCodec::RowOrder rowOrder)
-    : INHERITED(info, stream, bitsPerPixel, rowOrder)
+    : INHERITED(info, stream, inputFormat, bitsPerPixel, rowOrder)
     , fMasks(masks)
     , fMaskSwizzler(NULL)
     , fSrcBuffer(NULL)
@@ -135,3 +136,48 @@ SkCodec::Result SkBmpMaskCodec::decode(const SkImageInfo& dstInfo,
     // Finished decoding the entire image
     return kSuccess;
 }
+
+SkBmpMaskScanlineDecoder::SkBmpMaskScanlineDecoder(SkBmpMaskCodec* codec)
+    : INHERITED(codec->getInfo())
+    , fCodec(codec)
+{}
+
+SkCodec::Result SkBmpMaskScanlineDecoder::onStart(const SkImageInfo& dstInfo,
+        const SkCodec::Options& options, SkPMColor inputColorPtr[], int* inputColorCount) {
+    if (!fCodec->rewindIfNeeded()) {
+        return SkCodec::kCouldNotRewind;
+    }
+    if (options.fSubset) {
+        // Subsets are not supported.
+        return SkCodec::kUnimplemented;
+    }
+    if (dstInfo.dimensions() != fCodec->getInfo().dimensions()) {
+        SkCodecPrintf("Error: scaling not supported.\n");
+        return SkCodec::kInvalidScale;
+    }
+
+    if (!conversion_possible(dstInfo, fCodec->getInfo())) {
+        SkCodecPrintf("Error: cannot convert input type to output type.\n");
+        return SkCodec::kInvalidConversion;
+    }
+
+    // Initialize a the mask swizzler
+    if (!fCodec->initializeSwizzler(dstInfo)) {
+        SkCodecPrintf("Error: cannot initialize swizzler.\n");
+        return SkCodec::kInvalidConversion;
+    }
+
+    fDstInfo = dstInfo;

[scroggo, 2015/08/13 21:25:36]

Can you get this from the base class, which also stores it?

Aha - it looks like you are, and you never use this copy of it. Please remove.

[msarett, 2015/08/14 15:44:48]

Done.

+    fOpts = options;

[scroggo, 2015/08/13 21:25:36]

Maybe this should be stored in the base class as well?

[msarett, 2015/08/14 15:44:48]

fOptions is now stored in the base class.

+
+    return SkCodec::kSuccess;
+}
+
+SkCodec::Result SkBmpMaskScanlineDecoder::onGetScanlines(void* dst,
+        int count, size_t rowBytes) {
+    // Create a new image info representing the portion of the image to decode
+    SkImageInfo rowInfo = fDstInfo.makeWH(dstInfo().width(), count);

[scroggo, 2015/08/13 21:25:35]

nit: this->dstInfo()...

[msarett, 2015/08/14 15:44:48]

Done.

+
+    // Decode the requested rows
+    SkCodec::Result r = fCodec->decode(rowInfo, dst, rowBytes, fOpts);
+}