Bug 1118876 - Make tile edge padding work work with DrawTargetTiled. r=jrmuizel

gfx/layers/TiledLayerBuffer.h

@@ -546,15 +546,15 @@ TiledLayerBuffer<Derived, Tile>::Update(const nsIntRegion& aNewValidRegion,
     x += width;
   }
 
+  mRetainedTiles = newRetainedTiles;
   AsDerived().PostValidate(aPaintRegion);
-  for (unsigned int i = 0; i < newRetainedTiles.Length(); ++i) {
-    AsDerived().UnlockTile(newRetainedTiles[i]);
+  for (unsigned int i = 0; i < mRetainedTiles.Length(); ++i) {
+    AsDerived().UnlockTile(mRetainedTiles[i]);
   }
 
   // At this point, oldTileCount should be zero
   NS_ABORT_IF_FALSE(oldTileCount == 0, "Failed to release old tiles");
 
-  mRetainedTiles = newRetainedTiles;
   mValidRegion = aNewValidRegion;
   mPaintedRegion.Or(mPaintedRegion, aPaintRegion);
 }

gfx/layers/client/TiledContentClient.cpp

@@ -517,6 +517,7 @@ TileClient::TileClient(const TileClient& o)
   mManager = o.mManager;
   mInvalidFront = o.mInvalidFront;
   mInvalidBack = o.mInvalidBack;
+  mOrigin = o.mOrigin;
 }
 
 TileClient&
@@ -536,6 +537,7 @@ TileClient::operator=(const TileClient& o)
   mManager = o.mManager;
   mInvalidFront = o.mInvalidFront;
   mInvalidBack = o.mInvalidBack;
+  mOrigin = o.mOrigin;
   return *this;
 }
 
@@ -1056,6 +1058,31 @@ ClientTiledLayerBuffer::PostValidate(const nsIntRegion& aPaintRegion)
     mTilingOrigin = IntPoint(std::numeric_limits<int32_t>::max(),
                              std::numeric_limits<int32_t>::max());
   }
+
+  for (size_t i = 0; i < mRetainedTiles.Length(); ++i) {
+    TileClient& tile = mRetainedTiles[i];
+    if (tile.mFrontBuffer && tile.mFrontBuffer->IsLocked()) {
+      // Only worry about padding when not doing low-res because it simplifies
+      // the math and the artifacts won't be noticable
+      // Edge padding prevents sampling artifacts when compositing.
+      if (mResolution == 1) {
+        nsIntRect unscaledTile = nsIntRect(tile.mOrigin.x, tile.mOrigin.y,
+                                           GetTileSize().width, GetTileSize().height);
+        nsIntRegion tileValidRegion = GetValidRegion();
+        tileValidRegion.OrWith(aPaintRegion);
+
+        // We only need to pad out if the tile has area that's not valid
+        if (!tileValidRegion.Contains(unscaledTile)) {
+          tileValidRegion = tileValidRegion.Intersect(unscaledTile);
+          // translate the region into tile space and pad
+          tileValidRegion.MoveBy(-nsIntPoint(unscaledTile.x, unscaledTile.y));
+          RefPtr<DrawTarget> drawTarget = tile.mFrontBuffer->BorrowDrawTarget();
+          PadDrawTargetOutFromRegion(drawTarget, tileValidRegion);
+        }
+      }
+    }
+  }
+
 }
 
 void
@@ -1144,6 +1171,8 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
     }
   }
 
+  aTile.mOrigin = gfx::ToIntPoint(aTileOrigin);
+
   if (usingTiledDrawTarget) {
     if (createdTextureClient) {
       if (!mCompositableClient->AddTextureClient(backBuffer)) {
@@ -1247,26 +1276,6 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
     aTile.mInvalidFront.Or(aTile.mInvalidFront, nsIntRect(copyTarget.x, copyTarget.y, copyRect.width, copyRect.height));
   }
 
-  // only worry about padding when not doing low-res
-  // because it simplifies the math and the artifacts
-  // won't be noticable
-  if (mResolution == 1) {
-    nsIntRect unscaledTile = nsIntRect(aTileOrigin.x,
-                                       aTileOrigin.y,
-                                       GetTileSize().width,
-                                       GetTileSize().height);
-
-    nsIntRegion tileValidRegion = GetValidRegion();
-    tileValidRegion.Or(tileValidRegion, aDirtyRegion);
-    // We only need to pad out if the tile has area that's not valid
-    if (!tileValidRegion.Contains(unscaledTile)) {
-      tileValidRegion = tileValidRegion.Intersect(unscaledTile);
-      // translate the region into tile space and pad
-      tileValidRegion.MoveBy(-nsIntPoint(unscaledTile.x, unscaledTile.y));
-      PadDrawTargetOutFromRegion(drawTarget, tileValidRegion);
-    }
-  }
-
   // The new buffer is now validated, remove the dirty region from it.
   aTile.mInvalidBack.SubOut(offsetScaledDirtyRegion);
 

gfx/layers/client/TiledContentClient.h

@@ -274,6 +274,8 @@ struct TileClient
   nsIntRegion mInvalidBack;
   nsExpirationState mExpirationState;
 
+  gfx::IntPoint mOrigin;
+
 private:
   // Copies dirty pixels from the front buffer into the back buffer,
   // and records the copied region in aAddPaintedRegion.