5.1 - Source Radius

An overview of the Lighting example level, example 5.1: Source Radius (Static Lights)

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5.1 - Source Radius

This example shows the effect of changing the Source Radius property on a Static Light. We have two Static Lights with differing colors on either side of a Static Object. The colors are used just to show the difference more readily.

Source Radius simulates the size of the light source. As you may realize, small light sources, such as small LED lights, produce sharp shadows, particularly when casting very close to a surface. Larger light sources, however, have much softer or blurrier shadows. As previously mentioned in Example 2.1, Static Lights bake their information into a Lightmap. This means that in order for the quality of shadows to remain high, particularly with softer shadows, the Lightmap Resolution property will be key.

Source Radius (Static Light)

  • As mentioned before, Static Lights do not use Distance Field Shadows and bake everything into the light maps.

  • That makes it possible to have soft shadows depending on the size of the light source and the distance of the objects.

  • A big light source means soft shadows. A small light source means sharp shadows.

  • A big distance means soft shadows. A short distance means sharp shadows.

  • The color is just to show it better.

  • Lightmap resolution changes the quality.

  • We use this to simulate an indirect skylight coming through a window and casting very soft subtle shadows in the room.

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