Make SkImageFilter::applyCropRect() optionally compute srcBounds.
BUG=skia:4526
Review URL: https://codereview.chromium.org/1410553007
diff --git a/include/core/SkImageFilter.h b/include/core/SkImageFilter.h
index 0c3d4c2..d90df29 100644
--- a/include/core/SkImageFilter.h
+++ b/include/core/SkImageFilter.h
@@ -368,14 +368,18 @@
return false;
}
- /** Computes source bounds as the src bitmap bounds offset by srcOffset.
- * Apply the transformed crop rect to the bounds if any of the
- * corresponding edge flags are set. Intersects the result against the
- * context's clipBounds, and returns the result in "bounds". If there is
- * no intersection, returns false and leaves "bounds" unchanged.
+ /** Given a "src" bitmap and its "srcOffset", computes source and
+ * destination bounds for this filter. Initial bounds are the
+ * "src" bitmap bounds offset by "srcOffset". "dstBounds" are
+ * computed by transforming the crop rect by the context's CTM,
+ * applying it to the initial bounds, and intersecting the result
+ * with the context's clip bounds. "srcBounds" (if non-null) are
+ * computed by intersecting the initial bounds with "dstBounds", to
+ * ensure that we never sample outside of the crop rect (this restriction
+ * may be relaxed in the future).
*/
bool applyCropRect(const Context&, const SkBitmap& src, const SkIPoint& srcOffset,
- SkIRect* bounds) const;
+ SkIRect* dstBounds, SkIRect* srcBounds = nullptr) const;
/** Same as the above call, except that if the resulting crop rect is not
* entirely contained by the source bitmap's bounds, it creates a new
diff --git a/src/core/SkImageFilter.cpp b/src/core/SkImageFilter.cpp
index 9579302..25eecb0 100644
--- a/src/core/SkImageFilter.cpp
+++ b/src/core/SkImageFilter.cpp
@@ -391,11 +391,15 @@
}
bool SkImageFilter::applyCropRect(const Context& ctx, const SkBitmap& src,
- const SkIPoint& srcOffset, SkIRect* bounds) const {
- SkIRect srcBounds;
- src.getBounds(&srcBounds);
- srcBounds.offset(srcOffset);
- return fCropRect.applyTo(srcBounds, ctx, bounds);
+ const SkIPoint& srcOffset, SkIRect* dstBounds,
+ SkIRect* srcBounds) const {
+ SkIRect storage;
+ if (!srcBounds) {
+ srcBounds = &storage;
+ }
+ src.getBounds(srcBounds);
+ srcBounds->offset(srcOffset);
+ return fCropRect.applyTo(*srcBounds, ctx, dstBounds) && srcBounds->intersect(*dstBounds);
}
bool SkImageFilter::applyCropRect(const Context& ctx, Proxy* proxy, const SkBitmap& src,