I don't find a decent way to unwrap this prop without overcome the canvas.
As you can see in the image here's my uv, some parts are very small, and have a huge space to fill.
This object will have textures like normals and diffuse, i don't want distortion in the texture.
Low Object for a mobile game.
Replies
When unwrapping non-square materials I will create a custom checker material for those dimensions and apply that to the model. Then the UV editor to display that map as its background (upper right drop down menu). It sets the bounding box to display properly.
OR
You can leave the UV editor default setting as square and unwrap to two tiles, then squish it into the 0-1 space. It will look squished until you apply a non-square texture to it and set it to display that.
OR
IF you need more precision when switching back and forth between square/non-square layout. You can unwrap to two square tiles, then use the "UVW Xform" modifier to squash/stretch the U/V as needed. This will scale it exactly how you need it, instead of just using the scale tool and guessing.
Max will bake to whatever dimensions you set in the Render To Texture window.
If your UV layout is 1:2 and your output in RTT is 1:1 it will be squished.
IF your UV layout is 1:1 and your output in RTT is 1:2 it will be stretched.
The texture assignment is just to get the UV editor to display the correct bounding box.
I already use custom checker patterns for a few other reasons, this is just another positive side effect:
Basically the default checker patter is pretty basic and mostly garbage in my opinion.