no light: The light only starts emitting from the start of the barn.The most important things to know about the edge parameter: This ring is where the light no longer has an affect. This is the end of the penumbra for the edge region. When you start increasing edge, you will see one new guide ring show up in the Viewer. It allows light to pass through, but won't change the size of the penumbra (won't change shadow sharpness/softness). The edge parameter acts like a transparency slide outside of the edge of the barn. Think back to the idea that the barn opening is just a physical primitive. That shadow softness is based on the light size/barn position as explained above, not the edge parameter setting. You see falloff on a surface from your light because it's an actual shadow. Out of the box, the physically based barn has the edge parameter set to 0. A barn close to the light creates a large umbra.Ī barn far from the light creates a small umbra.A large light traveling through the barn shape casts a soft shadow (large penumbra) and shrinks the umbra.A small light traveling through the barn shape casts a sharp shadow (small penumbra) and has a bigger umbra.Two main things that change the quality of the light's umbra and penumbra: The edge of that shape in space in relation to the light size and distance determines the umbra and penumbra size. When trying to understand what it's doing, look at the shape of the barn where it begins (the window the light travels through). The Viewer Modifier guides show you the umbra and penumbra regions as you re-size the light or move the barn. The light casting through the barn creates an umbra and penumbra region based on that size and location. Cast light through an opening in space that creates physically accurate shadowing.īoth the size of the light as well as the position of the barn in relation to the light change how the light 'casts a shadow' onto the set.The Physical Barn acts as a window that only lets light in through the opening shape. Physical Barns can be used to simulate what would be done on a set. Think about it as a physical primitive that casts shadows. Physical Barns provide physically accurate shadowing, while Analytic Barns provide more precise user controls. PxrBarnLightFilter has two modes: Physical and Analytic.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |