Render the image as ASCII art for snapshotting: each pixel maps to aramp character by brightness (light -> space, dark -> '@'). Fullytransparent pixels render as a space.
Render a paint tree to an RGBA image of the given size via the softwarebackend. The tree is expected to be laid out in the same pixel space(its root box matching the viewport).
Render text to an RGBA image with the built-in 5x7 bitmap font (blackon white) via the software backend. scale is the pixel size of eachfont cell. A self-contained text-to-pixels path that needs no externalfont.