BuiltInEffectResolver

Lowers the built-in catalogue onto Media3's effect classes.

Lowers the built-in catalogue onto Core Image.

Resolves filmstrip's built-in effects for the current platform.

Lowers the built-in catalogue onto a filter graph.

Every lowering is a pure function of the spec and the resolved Attributes, and needs no toolchain installed. An overlay is the one lowering that reads anything. An image overlay needs the picture's own pixel size to place it. One on an HDR grade decodes the picture to carry it onto the grade's signal, and one on an SDR grade decodes a picture that describes its color, or a JPEG XL, to draw it in that color. A text overlay is drawn to a picture with the JVM's own fonts and placed the same way. The backend's OverlayPictureDecoder decodes and sizes every picture when there is one, and the JDK reads them when there is none.

Lowers the built-in catalogue onto WebGL pass declarations.

Only the effects that are a texture-space transform or a color matrix resolve here. A rotation is a texture matrix about the frame's centre, and a scale resolves to a pass that samples the frame unchanged, since the output size it sets is negotiated before the compositor is built. A pan is a texture matrix the compositor asks for again on every frame, at the region regionAt gives for that frame's composition time.

Overlays are rasterised here, text on the spot and images from the ones prepare decoded, and resolve to a raster the compositor draws where the effect says. Text carries its straight sixteen-bit samples, and text too large to draw is refused with the reason its raster gives. Text or a picture longer on a side than the capabilities' maxTextureSize is refused, since WebGL uploads nothing past it.