Case Study - Katana using normal and specular maps

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KBwarning.png Warning: This case study covers Pre-Beta upcoming features that are subject to change.

This case study explores how June Dion used normal and specular maps to add significant detail to a mesh object imported from LightWave. The completed product is available for purchase on the Second Life Marketplace at https://marketplace.secondlife.com/p/BR-Materials-Katana/4922401.

KBnote.png Note: This document explains how to use LightWave to create textures for the normal and specular mapping (materials) features of Second Life. For information on LightWave's basic operations, please refer to LightWave's documentation resources.

Modeling and Template Texture

June Dion Katana Figure 1.jpg First, create a mesh object in LightWave Modeler. For this study, we're using a basic fantasy-style katana. During the same step, we've also created a UV map for the object. You will need 2 versions of the model; one with triangle polygons and one with quad polygons. Triangle polygons are necessary for baking textures, and will also help to keep clean shading in Second Life.

Baking Textures

To bake textures, import the model to LightWave Layout, then select the model on Camera > Surface Baking Camera. Render the UV and save the image. Use this image as a base for your normal and specular maps as well as the object's texture. June Dion Katana Figure 2.jpg

Creating the Normal Map

June Dion Katana Figure 3.jpg Now we're going to use bump displacement to add the appearance of detail to the model. Make a grayscale texture to represent the bump details that will overlay the existing textures; in this case, we're using a net pattern on the hilt of the sword. Apply SubPatch on the quad polygon model, then export to LightWave Layout.

In the Surface Editor, apply the grayscale bump map as a Bump texture. Go to Object Properties > Deform and turn on Bump Disp to display the deformation of the model. You can adjust the Distance parameter to refine the shape. This display looks rough, but you can use Geometry > Render Subpatch for render output.

Exporting the Normal Map

To export the normal map, you need a plugin called DP Kit. Download and install it if you do not already have it.

In the Surface Editor, open the Node Editor, then select DP Kit > Tools > Normal Cast. On the settings panel for Normal Cast, select the UV and Projection Distance, then connect to Diffuse Shading. Export the normal map with Camera > Surface Baking Camera.

June Dion Katana Figure 4.jpg

Creating and Exporting the Specular Map

June Dion Katana Figure 5.jpg To create a specular map, create another grayscale texture and use a paint program to design your pattern. Use white for shiny areas and black for matte areas. For this example, most of the model will be shiny.

Exporting to COLLADA and importing to Second Life

Export the triangle-polygon model to COLLADA format using a COLLADA exporter plugin. Import the model and your textures to Second Life, then edit the model and use the Textures tab of the Build Tools to apply your base texture, normal map, and specular map to the finished object June Dion Katana Figure 6.jpg