Looking for a way to replace all materials on INNER surfaces in solid objects

Hello Sketchup community, I have a small question that I could not figure out while Googling.

I am creating maps for games in the Source engine, I am also using Sketchup as a medium.

The way the source engine handles a map is quite different then Sketchup.
In a Source map every face has to be a solid object (either a cube or a triangular form)

I am using a Sketchup plugin to extrude all faces of a model so that every face becomes a solid object.

I then need to determine what parts are visible in this model and what parts are not visible and will not be compilled into the map. I do so by texturing the outside faces manually (photo 1) and then use a Green “NODRAW” texture on every inside face (photo 2) so that this face will be left out of the compilation.

Is there a quick and easy way to texture all inside faces of a solid object in one go? As you can see the problem that arises in photo 2: I would have to manually paint every single face green(ex)… I cannot replace ALL untextured areas with green because the areas in photo 1 need to be textured differently(exex)

ex (The small untextured strokes visible in the picture)
exex (I am meaning the small side faces of all cubes in photo 1 that are left untextured)


If you modify the default material so that its back face color is the one you want, this will affect all of your model. When you paint the outside face with another material, the back is unchanged!


With ThruPaint (a part of FredoTools) you can choose to only paint back faces…


Exactly what I was looking for! Thanks a bunch :smile: this will definally increase the speed of my project!

This questionnaires is now solved ^^

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