Sunday, September 30, 2012

Blender Procedural Stones

modeled in Blender
Normal + AO map baked in Blender
Cavity Map generated in xNormal
Texturing done in Photoshop

~200-300 tris each
~20-30 tris collision model
Diffuse Map, Specular Map (Diffuse Alpha Channel), Normal Map
1 UV Channel (lightmap ready)

UDK Screenshots (prebaked Lighting, 128px² lightmap)

Saturday, September 8, 2012

[How-To] create Self-Shadowing Materials (UDK/UE3)

An esay approach on implementing self shadowing for UE3 to increase the quality of normal and bump offset/parallax mapped materials even further. It does require a heightmap and is useful for bumpy surfaces like bricks and cobblestones.


The idea is quite simple. Offsetting the height map along the light direction and comparing it's value with the actual height determines which areas are shadowed. Scale and darkness/hardness of shadows can be controlled by adjusting the offset and contrast value.

The technique is not very expensive - adding an extra of 5-10 point light shader instructions (depending on the contrast value). It's possible to save some instructions by adding a constant clamp (0-1) before the contrast adjustment and by replacing the power node with a series of multiply nodes (e.g. 3x multiply by itself = power of eight).