Blend Layer Gradient Mask

Turns a blend-gradient into a mask on the layer: instead of drawing color, the layer itself fades to transparent wherever the stops are transparent. Takes a boolean, and the default is false.

Only the stops’ alpha is read. The colors’ RGB, blend-gradient-alpha, blend-gradient-cs and blend-gradient-hue are all ignored, as is blend-gradient-mode.

A layer’s gradient mask always fades to transparent and never into a color, because a blend layer has no bg. This is what makes a soft-edged layer: pair it with blend-gradient-type=radial for a vignetted layer.

Use blend-gradient-mask[N] to target a specific blend layer, where N is 0–3. Layer 0 is either the bare blend-gradient-mask or blend-gradient-mask[0]; if both are supplied, the bare name wins. A layer never borrows another layer’s spelling.