Using the Layer Editor
In maya to organize your screen create 3 Layers (“high”, “low”, “collision”) to better organize your screne
Add all the geometry created in the last tutorial to the “high” Layer by first selecting all objects and then RMB on the layer “high” > “Add selected Objects”
Select the Layer “low”, so that the new Objects created are created in that Layer.
Using the same grid size as in UDK allows you to create modular assets that can be easily placed into a Level.
I adjusted my base to be 16 UnrealUnit (uu) high.
Low Poly Model
- Create > Polygon Primitives > Cylinder(Subdivisions Axis = 16)
- Rename it to ”pillar_column”
- Scale the cylinder to fit the base mesh
- RMB on the cylinder > Assign Favorite Material > Blinn (rename it to “mat_column”)
correctly scaled Cylinder
- Duplicate the “pillar_column” (Ctrl-D)
- Rename it to ”pillar_base”
- In the side view, move the vertex points on the y-axis to fit the base mesh.
- Mesh > Insert Edge Loopand then scale the loop to create a simpler model (repeat as few times as possible but still retaining the original silhouette of the object)
Finished Model, after adding several edge loops and proper scaling
In many cases a new UV-Mapping has to be created with the UV-Layout tools. In this case by using the Edge Loop tool I tried to avoid that for this tutorial.
- Window > UV-Texture Editor
Default UV-Layout for a Cylinder
- Select the “pillar_base”
- Use the “Move-UV Shell Tool” to change the position of the UV-Shells. Pressing R switches to the scale tool.
- Arrange the UVs into a similar way as in this image:
- Repeat for “pillar_column”
- Window > UV-Layout
- select the “pillar_base” (in Object mode)
- (UV-Layout) Polygons > Copy UVs to UV-Set > Copy UVs into new UV set (options) (name it lightmap)
- Repeat for “pillar_column”
Create Normal Map
A normal map is similar to a bump map, however the amount of displacement information is stored for each axis. Like a bump map the height displacement is stored in grayscale. The x,y,z information is mapped to the r, g, b channels of an image.
Generate Normal Map
1. Switch to the Rendering view
Switch to Rendering -View
2. Lighting/Shading > Transfer Maps… Change following values in the tabs:
- Target Meshes: Select the Low Poly Object (“pillar_base”) and press the button “Add Selected”
- Source Meshes: Select the High Poly Object (“pillar_base_high”) and press the button “Add Selected”
- Output Maps: Select your output directory, change the Fileformat to Targa, the Mapspace to “Tangent Space”
- Connect Output Maps: Connect Maps to: Assigned shader (easier for the export to UDK late
- Maya Common Output:Adjust the Map width for your puropses, Sampling Quality 8×8 for final export
Transfer Maps Settings Part 1
Transfer Maps Settings Part 2
3. Save your scene file
4. Click on Bake and wait while the normal map is generated
Testing and adjusting Normal Maps
Simply press render to view the generated Normal map
If the map looks wrong. In the Transfer Maps tool, Target Meshes > Display Both to preview what maya takes all into account when calculating the normal map.
Dealing with normal Map errors
Adjust the Search envelope to include objects that are further away.
Finished ColumnNormal Map
Finished Base Normal Map
To create a normal map a low poly and a high poly object is needed. This method reduced the original tris count from 10526 to 400 for the object.
In the next part we will look at how to use the map correctly in UDK.
While generating Normal Maps it many errors can occur (and it takes a lot of time). Before changing the Sampling quality always test it by doing a test render in low sampling quality.
The Lightmaps created in this tutorial are not adjusted properly and only serve to prevent UDK errors.