I use a script to draw wireframe model use GL class. I have question. How can I make my lines overlapin the the model without being hidden? How I can see everything? Is there a way to set opacity of a line?

The lines you are using at the moment are depth checked. Which means that your model is in front of your GL.LINES. To make sure that your lines are drawn over the rest of your models:

Use the `OnPostRender` method. This makes sure that they are drawn in the last render loop. Alternatively, but I don't know how: draw your lines in a seperate layer between default and GUI.

This will at least make sure that your lines are drawn as last, but still, they are checking the Z-buffer (depth-buffer) of there is anything in front of them. So the next thing you have to do:

Disable depth buffer reading. This can be done in the shader you are using to draw the lines. Use `ZTest = always`. See the reference here.

Alternatively, and less accurate, because it kills your complete z-buffer: Clear the z-buffer before rendering your lines. Call `GL.Clear(true, false, Color.Black)`. This will clear your depth buffer, which is not a wanted process. The best way is disabling the ZTest.