set material of draw canvas to render target

hi

you can set the material of

draw material (target canvas) in conjunction with begin draw canvas to render target

but somehow it does not appear to work or do much (anything)

i set the material to a color yet it comes out black

thanks

really had to play around with the settings to get it to work
only screen size and screen coordinates seem to work
and not coordinate size nor coordinate position
or i am completely misinterpreting their meaning
which is also not easy to source