Wednesday, January 16, 2013

UDK Benchmark WiP #4

After creating the cave scene for testing multiple dynamic lights I am now working on the outdoor area whose key features will be a dynamic sunlight and lots of foliage (=alpha testing).

Wooden Props

The workflow for all objects with a unique texture (e.g. table, cart, bench, barrel...) is almost identical to each other. Game and LoD mesh is modeled from scratch with as much matching UV coordinates as possible. Based on the game mesh I did create a high poly sculpt to bake a normal map for correct shading and large scale details. This normal map is being combined with a small detail normal map which has been generated out of the diffuse map.
For objects with multiple materials (usually bigger ones with tileable textures) I'm using a low res texture atlas for the LoD model to cut down the amount of materials to 1.

Here's an example of the wooden planks which are part of the bridge model:


For performance reasons I'm using static meshes for most trees of small and mid scale. Only a few big / special trees are created with speedtree to save me some time.

The triangle count of these 3 trees is ~1300/1800/900:

Turntable .gif (4.8MB):

Instead of fiddling around with photo resources I just modeled some grass by hand. These grass blade meshes are easily editable and can be rendered from an orthographic side view to quickly get a diffuse and alpha opacity map.

Landscape Meshes

To create an interesting landscape I decided to combine custom rock meshes with UE3' landscape tool.

Modeling is done in at least 2 iterations with increasing subdivisions and details. This makes it easily possible to use work-in-progress meshes as LoD models:

For both, the grass parts of those rock meshes and the UE3 landscape I'm using a material with triplanar textur projection for seamless blending between both. As a side effect the custom meshes can be textured without any seams or heavy texture stretching.