[feature request] Lock Render target's size to internal resolution

Hello,

it would be really useful if instead of setting the resolution of render target in advance we could let the engine manage it and keep the same as internal resolution of render target. For example if I want to capture the scene and render it in blendable(for some post processing effect) I can’t use ScreenPosition node as it uses internal resolution of ScreenTexture and I am forced to remap UVs(and unfortunately I, and based on the forum comments, many other developers have not been able to get right).

Thank you.