enum PixelFormat

Byte order of one pixel handed to GPUResourceHost.uploadPixels, in memory order.

The four that real rasterisers write, so a caller never swizzles: poppler's Splash writes bgrx8, cairo's ARGB32 is bgra8 on a little-endian machine. Encoded sRGB, like every colour here. The a formats are straight alpha; the x formats are opaque and their fourth byte is ignored.