"EnTerr" wrote:
This is hopelessly undocumented - but i will take a guess you can use color attribute for the rectangle?
If so, it is likely RGBA and by varying the Alpha channel between 0 and 255 you can get levels of transparency.
roImageCanvas colors are actually ARGB, but you are correct. Set the color to an ARGB value and set the CompositionMode to "Source_Over" and that will alpha blend the TargetRect over the underlying layers.
My Channels: http://roku.permanence.com - Twitter: @TheEndlessDev
Instant Watch Browser (NetflixIWB), Aquarium Screensaver (AQUARIUM), Clever Clocks Screensaver (CLEVERCLOCKS), iTunes Podcasts (ITPC), My Channels (MYCHANNELS)