message ImageInfo

A registered image: the id to put in a draw command, and the size it actually decoded to.

The size comes back because the client needs it to lay out — an Image view sizes from its texture — and it cannot read the file's header itself without doing the decode this call exists to avoid. It is the decoded size, not the file's: a maxPixelSize cap changes it, and laying out against the uncapped dimensions would scale every capped image wrongly.