Silhouette - Arnold User Guide
Silhouette
The edge line detected by the object/shader ID Difference is called silhouette. If this option is enabled, silhouette lines are drawn using Silhouette Color, Silhouette Width Scale, Silhouette Opacity, and Silhouette Tonemap. If this is disabled, silhouette lines inherit the setting for inner edge lines, in other words, they are drawn using Edge Color, Edge Width Scale, Edge Opacity, and Edge Tonemap.
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| 0 (default) | 1 |
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| Enabled | Disabled |
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| Enabled | Disabled |
The effect of silhouette is also evident on the edges of the pillars and steps (separate objects) in the interior scene below.
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| Disabled (default) | Enabled |
Silhouette Edge distortion can be achieved by adding a Cell Noise to the Silhouette Edge, evident in this tutorial here.
Color
The color of the Silhouette Edge. The line style can be controlled with a texture here.
Tone Map
Connect a ramp node here to change the Silhouette Color based on the shading result of the base.
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| No Tonemap | Ramp RGB -> Silhouette Tonemap |
Tonemap Hue Saturation
When the hue and saturation tonemaps are used in conjunction with the pre-existing tonemap, the pre-existing tonemap parameter will only be used for the value (a sort of brightness) in the direct light of the HSV mapping, whereas without it would produce full RGB colors mapped to the value of direct light. This allows for the full set of HSV components to be mapped independently through these two shader parameters.
The connected shader's U coordinate drives direct light hue and the V coordinate drives saturation, which enables textures to map the toon shader's response to colored lighting.
ensure to set the Image shader's Wrap U and Wrap V to Clamp and Filter Type to Closest for best results).
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| No Silhouette Tonemap Hue Saturation | Image -> Silhouette Tonemap Hue Saturation |
Opacity
Controls the transparency of the silhouette.
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| 0 (default) | 0.5 | 1 |
Width Scale
The maximum width of the silhouette contour lines is determined by the Width parameter of the Contour Filter. The actual width is the multiplication of it and this parameter. The line style can be controlled by combining this with a texture.
The Toon shader forces the silhouette width to always be wider than the inner edge width.
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| 0.25 | 0.5 | 1 (default) |
To increase the Silhouette Width Scale above 1, you will need to increase the Contour Filter Width. However, this will increase render times.