commit 9b9497ef14f23562a95afe989d1efe41c603a6f6
author msarett <msarett@google.com> Thu Feb 11 13:29:36 2016 -0800
committer Commit bot <commit-bot@chromium.org> Thu Feb 11 13:29:36 2016 -0800
tree 73bcf52cd5174899c13c816d02092faccdc8453d
parent f8289d9bd1faff400728cb8e1ac0b1aa68bfbc32

Implement onSkipScanlines() for bmp and wbmp

TBR=reed@google.com
BUG=skia:4270
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1691083002

Review URL: https://codereview.chromium.org/1691083002

src/codec/SkBmpRLECodec.cpp

diff --git a/src/codec/SkBmpRLECodec.cpp b/src/codec/SkBmpRLECodec.cpp
index 05691cc..1b95acc 100644
--- a/src/codec/SkBmpRLECodec.cpp
+++ b/src/codec/SkBmpRLECodec.cpp
@@ -201,7 +201,7 @@
 void SkBmpRLECodec::setPixel(void* dst, size_t dstRowBytes,
                              const SkImageInfo& dstInfo, uint32_t x, uint32_t y,
                              uint8_t index) {
-    if (is_coord_necessary(x, fSampleX, dstInfo.width())) {
+    if (dst && is_coord_necessary(x, fSampleX, dstInfo.width())) {
         // Set the row
         uint32_t row = this->getDstRow(y, dstInfo.height());
 
@@ -234,7 +234,7 @@
                                 const SkImageInfo& dstInfo, uint32_t x,
                                 uint32_t y, uint8_t red, uint8_t green,
                                 uint8_t blue) {
-    if (is_coord_necessary(x, fSampleX, dstInfo.width())) {
+    if (dst && is_coord_necessary(x, fSampleX, dstInfo.width())) {
         // Set the row
         uint32_t row = this->getDstRow(y, dstInfo.height());
 
@@ -316,7 +316,9 @@
     // Because of the need for transparent pixels, kN32 is the only color
     // type that makes sense for the destination format.
     SkASSERT(kN32_SkColorType == dstInfo.colorType());
-    SkSampler::Fill(dstInfo, dst, dstRowBytes, SK_ColorTRANSPARENT, opts.fZeroInitialized);
+    if (dst) {
+        SkSampler::Fill(dstInfo, dst, dstRowBytes, SK_ColorTRANSPARENT, opts.fZeroInitialized);
+    }
 
     // Adjust the height and the dst if the previous call to decodeRows() left us
     // with lines that need to be skipped.
@@ -500,6 +502,13 @@
     }
 }
 
+bool SkBmpRLECodec::skipRows(int count) {
+    const SkImageInfo rowInfo = SkImageInfo::Make(this->getInfo().width(), count, kN32_SkColorType,
+            kUnpremul_SkAlphaType);
+
+    return count == this->decodeRows(rowInfo, nullptr, 0, this->options());
+}
+
 // FIXME: Make SkBmpRLECodec have no knowledge of sampling.
 //        Or it should do all sampling natively.
 //        It currently is a hybrid that needs to know what SkScaledCodec is doing.