FMP 5- Upper Section of Classroom and Material Experimentation

 The clasroom mod kit is now complete, excluding doors. I also changed the building generator slightly, adapting it better to the needs of our project and improving the UI. I decided to experiment with lighting and materials in engine, which I did in my test level. This lead to me tweaking the plaster material and trim sheets to better suit a decay blend between clean and worn walls. 

The window was a challenge to unwrap, and will not be well suited to the vertex painted masks, but selective vertex paint can still add variation to the texture without causing artifacts. The ceiling and upper walls use a single trim sheet, but the beams are separate due to their size; a larger tiling material is required to maintain the necessary variation. The wooden bands on the ceiling pieces serve well to eradicate seams and tiling errors, but are not ideal for baked wear masks, again requiring selective vertex paint. The Painter file where I baked the wear masks for the upper pieces is currently crashing constantly, which is an issue I will need to resolve. I will also need to create a custom piece function for the upper wall window pieces. 

Master material (needs cleaning)

Reference

The lighting and layout of the room are based our concept artist's sketches, with real-world reference to support the creation of materials. I used a mask created in Substance Designer to blend between clean and worn plaster, but it still doesn't quite look right. I subtracted the same mask with an exponent applied to get the edge of the mask and apply dirt and AO to it, but I think I need to blur the mask a bit as it is forming flat plateaus instead of maintaining a constant spread. 

Strange black plateaus caused by "stepped" mask

Nodes for fixed beams and rotating opposite normals

I fixed the beams by deleting the first point before the in-between points are deleted, which aligns the beams when the spacing is a multiple of three, but to align them for a multiple of two the first point must be deleted after the in-between points. I can probably automate this later with a switch-if node, but for now the multiple of three is all I need. I also needed to make the upper walls only appear on two sides, which I did by using the two side ceiling logic, but the corners also needed to face the same way as the points on the straight edge. This was more difficult, but I eventually solved it by rotating pairs of opposite facing normals to face the correct direction. 

I used pack and instance copy to points nodes instead of the unreal attribute to instance the geometry, however I would prefer to use the latter for more efficiency. I did attempt to use this more efficient method, but in Unreal the geometry didn't seem to inherit the outwards facing normals and ended up facing in the same direction. This should not happen, as the normals are clearly working in Houdini, and I have tested the normals and other attributes on other nodes, but the solution and root of the problem remain elusive.