gecko/mobile/android/base/gfx/VirtualLayer.java
2012-05-21 12:12:37 +01:00

39 lines
1.3 KiB
Java

/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package org.mozilla.gecko.gfx;
import android.graphics.Rect;
public class VirtualLayer extends Layer {
public VirtualLayer(IntSize size) {
super(size);
}
@Override
public void draw(RenderContext context) {
// No-op.
}
void setPositionAndResolution(int left, int top, int right, int bottom, float newResolution) {
// This is an optimized version of the following code:
// beginTransaction();
// try {
// setPosition(new Rect(left, top, right, bottom));
// setResolution(newResolution);
// performUpdates(null);
// } finally {
// endTransaction();
// }
// it is safe to drop the transaction lock in this instance (i.e. for the
// VirtualLayer that is just a shadow of what gecko is painting) because
// the position and resolution of this layer are always touched on the compositor
// thread, and therefore do not require synchronization.
mPosition.set(left, top, right, bottom);
mResolution = newResolution;
}
}