pushShaderMask abstract method
- Shader shader,
- Rect maskRect,
- BlendMode blendMode,
- {ShaderMaskEngineLayer? oldLayer,
- FilterQuality filterQuality = FilterQuality.low}
Pushes a shader mask operation onto the operation stack.
The given shader is applied to the object's rasterization in the given rectangle using the given blend mode.
If oldLayer is not null the engine will attempt to reuse the resources
allocated for the old layer when rendering the new layer. This is purely
an optimization. It has no effect on the correctness of rendering.
Passing a layer to addRetained or as oldLayer argument to a push
method counts as usage. A layer can be used no more than once in a scene.
For example, it may not be passed simultaneously to two push methods, or
to a push method and to addRetained.
When a layer is passed to addRetained all descendant layers are also considered as used in this scene. The same single-usage restriction applies to descendants.
When a layer is passed as an oldLayer argument to a push method, it may
no longer be used in subsequent frames. If you would like to continue
reusing the resources associated with the layer, store the layer object
returned by the push method and use that in the next frame instead of the
original object.
See pop for details about the operation stack.
Implementation
ShaderMaskEngineLayer pushShaderMask(
Shader shader,
Rect maskRect,
BlendMode blendMode, {
ShaderMaskEngineLayer? oldLayer,
FilterQuality filterQuality = FilterQuality.low,
});