Render to texture, texture size independent of context's window size

Hello,

I'm having a problem rendering "multiple gridshapes" to a texture.

So far the "multiple gridshapes" are all getting rendered to a texture, I then want this texture to be mixed in a 4way mixer with some videos and jit.gl.ogre, the videos and the ogre are all being rendered at 1280x720 so I want the "multiple gridshapes" to be sent to the mixer at that 1280x720 resolution.

The only way I can get the above to work is set the "multiple gridshapes" contexts window with @size 1280 720, however this leaves me with 2 windows being rendered at 1280x720- my final mixed output's jit.window and the multiple gridshapes jit.window.

Ideally I would like the "multiple gridshapes" window to be rendered small say 320x240 and used as a preview window, but as soon as I reduce the size of the "multiple gridshapes" window the texture being sent to the mix is reduced in size.

I've searched the forums extensively and tried messing about with @adapt, @dst_dim, @dim, @usedstdim but im going on guesswork and it isnt working, hopefully someone understands this render to texture business better than me!

Here's a patch that illustrates what im doing,

Hope someone can help.