Merge "RenderEngine: Limit the size of blur input to the display size" into udc-dev am: be2ac9c753

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/native/+/24193668

Change-Id: Ief8161d04df8932e2ac461cb6cc784a416878fb4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/libs/renderengine/skia/SkiaRenderEngine.cpp b/libs/renderengine/skia/SkiaRenderEngine.cpp
index fda6ea189e..76ebf9d0c2 100644
--- a/libs/renderengine/skia/SkiaRenderEngine.cpp
+++ b/libs/renderengine/skia/SkiaRenderEngine.cpp
@@ -813,8 +813,20 @@ void SkiaRenderEngine::drawLayersInternal(
             if (!blurInput) {
                 blurInput = activeSurface->makeImageSnapshot();
             }
+
             // rect to be blurred in the coordinate space of blurInput
-            const auto blurRect = canvas->getTotalMatrix().mapRect(bounds.rect());
+            SkRect blurRect = canvas->getTotalMatrix().mapRect(bounds.rect());
+
+            // Some layers may be much bigger than the screen. If we used
+            // `blurRect` directly, this would allocate a large buffer with no
+            // benefit. Apply the clip, which already takes the display size
+            // into account. The clipped size will then be used to calculate the
+            // size of the buffer we will create for blurring.
+            if (!blurRect.intersect(SkRect::Make(canvas->getDeviceClipBounds()))) {
+                // This should not happen, but if it did, we would use the full
+                // sized layer, which should still be fine.
+                ALOGW("blur bounds does not intersect display clip!");
+            }
 
             // if the clip needs to be applied then apply it now and make sure
             // it is restored before we attempt to draw any shadows.