Grasshopper Rhino Tab - Viewport Creation

Using the Model Viewport component, how do I create a viewport window of a set size?

I’ve tried attaching a Model View component and filling out the inputs (Parallel projection, X and Y domain sizes) but all it seems to give me no matter what is a squarish viewport of the same size, no matter what I input.

Long story short, I’m trying to export a viewport as a bitmap, so I can parametrically create a transparency bitmap for a complicated mesh panel that it isn’t worth letting GH take 15 minutes to create a full solid object. Essentially, I’m creating a rectangle the size of my panel (which will later get populated with circles for holes), and want to create a viewport with the same size/ratio and export that as shown below.

I feel like I must be missing something simple with the viewport creation, but I couldn’t find anything in the documentation or by searching the forum.

ViewportTest.gh (16.7 KB)