Lightmapped Vertex-Lit
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Lightmapped Vertex-Lit

Lightmapped Properties

This shader is a complex version of a Self-Illuminated shader. It uses a secondary Lightmap texture that defines light "emitted" from the object onto itself (and nothing else). The Lightmap's RGB values define the color of light, and its alpha channel can be used to control glow. The Lightmap texture also uses the secondary UV map of the mesh for controlling the placement of light, which can differ from the primary UV map. This shader allows you to use baked colored light, radiosity with color bleeding and other funky effects.

This shader is handy when your Base texture and/or Bumpmap are tiled across your object multiple times and its Self-Illumination can't be tiled along with them. Most 3D modeling applications have tools to "bake" lighting into a texture and/or automatically compute a suitable lighting UV map. However, not all 3D modeling applications can export a secondary UV map properly.

Any scene lights will add illumination on top of the object's illumination. So if you have a Lightmapped level with baked lighting, and a rocket with point light flying, it will just add lighting - i.e. it just works.

Vertex-Lit Properties

Vertex-Lit is the simplest and least expensive shader. Any lights shining on it are rendered in a single pass, and therefore faster than any pixel-lit shader. Even lights marked as Pixel lights will be rendered as Vertex lights when using this shader. This shader calculates lighting at vertices only, so interpolated "overall lighting" is drawn over the actual pixels of the object's triangles.

Because it is vertex-lit, it won't display any pixel-based rendering effects, such as light cookies, bumpmapping, or shadows. This shader is also much more sensitive to tesselation of the models. If you put a point light very close to a cube using this shader, the light will only be calculated at the corners. Pixel-lit shaders are much more effective at creating a nice round highlight, independent of tesselation. If that's an effect you want, you may consider using a pixel-lit shader or increase tesselation of the objects instead.

Performance

Generally, this shader is cheap to render. For more details, please view the Shader Peformance page.