ReadonlystatsCumulative GPU passes dispatched and shaders compiled; useful in tests and for profiling.
Returns the chain's output. The texture belongs to the pipeline (or is the source itself for an empty chain): do not destroy it; it stays valid until the next run, setSource or destroy.
Sets the input working texture. Not owned: the caller keeps it alive and destroys it.
scale is its resolution relative to the full image (see ChainOptions).
Runs a filter chain on the GPU, caching each stage's output so that a change only recomputes from the first affected stage onwards. Consecutive pointwise steps form a single stage (one pass); each multipass filter is a stage of its own. Shaders depend only on the filters, so moving a slider never recompiles.