I used a transparent cutout shader to display the textures "properly", but there were problems of course, specifically because I used alpha testing to render the opaque pixels from the texture while writing to the depth buffer. In the next pass of the shader I turned depth buffering off and prevented any pixels from the depth buffer from being written again, after that I had turned alpha blending on and it wrote the transparent pixels. It all seemed fine and dandy but it did cut some of the more transparent pixels off.
I removed the first pass and now I only have the second pass in the shader (the shader is close to an unlit transparent but with vertex coloring) and it seems to render fine, expect for the sorting of the triangles in the mesh, which I had to add in to my mesh rendering. The only problem with it was with the rendering order with other gameobjects, they were either always shown on top of the GUI or the GUI renderers din't show over the others renderers even if they were closer to the camera.
This was really weird and I looked everywhere for this problem, I though that the problem was in the mesh as the unity's cube mesh would render correctly with the same shader and this puzzled the hell out of me. Finally I found the answer and it was in the material, more precisely in the renderQueue member of the material. The renderQueue was set to 1 every time a texture is changed by script in the material (maybe by modifying other members in the material as well), the number in the renderQueue is the same tag as the shader's Queue tag which are:
- Background, 1000
- Geometry, 2000
- AlphaTest, 2450
- Transparent, 3000
- Overlay, 4000
The renderQueue tag is set automatically if the material is modified by unity, but if it is modified by script it will set it to 1 which is nothing and it would result in a very chaotic rendering order, by setting the renderQueue to 3000 would result in a correct rendering order with other gameobjects.
