Manual Modules Hair Objects and Tags Light Tag
Light Basic TagTag Properties
This setting defines whether or not a light source should illuminate the hair. It’s also possible to exclude light sources from lighting hair.
Sources of light without a Light Tag will, by default, have an effect on the hair. Light sources can also be included or excluded in the Hair Render menu’s Lights tab, in the Render Settings.
Use this setting to define the type of shadow the hair should cast. The following options are available:
- None: The hair will cast no shadows, regardless of any light source settings.
- Auto: The shadow type (if any) will be determined by the light sources.
- Soft Shadows: The hair will always cast soft shadows, regardless of any light source settings (Hair-specific shadow maps settings should still be adjusted using this menu). All settings, with the exception of “Traced Width”, apply to soft shadows.
- Ray Traced: The hair will always cast hard shadows, regardless of any light source settings (the “Reflection / Refraction / Traced Shadows” setting in the “Render” tab must be active).
Trans. Threshold [0..100%]
Depth Threshold [0..10000000m]
A short description of how shadow maps function in Hair: Special “depth shadow maps” are used that calculate shadow maps for each individual light (from the point of view of each light), and save varying states of shadows (pixel by pixel) in the distance. This is necessary, for example, in order to effectively cast shadows in a room in which numerous partially transparent “objects” and hair are combined.
These settings, which can normally remain unchanged, are designed to save memory (internally) at the expense of shadow quality. When shadow maps are calculated, shadow map information that does not exceed the values entered for these settings will be ignored or removed. Any changes in shadow quality are nominal. Higher values will result in less accurate shadow maps (for the most part only noticeable in shadows cast within the hair), which, in turn, also requires less memory.
Antialiasing internally smoothes shadow maps. For extremely thin hair (in the area of 0.001m), an inactive “Antialiasing” setting can result in the hair casting a shadow that is barely visible. If “Antialiasing” were active, its smoothing effect would practically eliminate this shadow. Please note that normal CINEMA 4D antialiasing (“Best”) will smooth the resulting “pixelated” shadows. Otherwise, an active “Antialiasing” setting will ensure soft shadows are rendered.
Use this setting to define the radius within which shadow maps will be sampled, from which an average value can be ascertained. Simply put: The larger the sample size, the softer the shadow will be.
Shadow Map
Resolution [64..65536]
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| Increasingly large shadow maps from top to bottom. Notice also the slight change in the shadows cast within the hair itself. |
This setting applies only to raytraced hard shadows. Instead of using a narrow raytrace beam (a 0° angle of spread), a cone with a spread defined by this setting will be emitted. The result: A higher value will make “hard” shadows softer. Render times will, though, increase dramatically if a value greater than 0° is used. We suggest you use a value between 0° and 1°..