SDF. What is it?
SDF: Scalar Distance Field
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A SDF is a function which calculates the distance to the surface of an object by using the space that object contains. You may notice that SDFs usually function with anything that has a volume or a VDB attribute.
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Here are some common SDF nodes: (As of Houdini 17.5)
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SDF Geometry Nodes:
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Paint SDF Volume
Volume SDF
VDB Topology to SDF
VDB smooth SDF
VDB reshape SDF
VDB re-normalize SDF
VDB Morph SDF
VDB Activate SDF
Convert VDB
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SDF Dynamic Nodes:
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SDF Representation
Gas SDF to Fog
Gas Particle to SDF
Gas reinitialize SDF
Gas geometry to SDF
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What VFX Simulations Use SDF?
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In Houdini some operations and simulations you might use SDFs for are:
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Explosions
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Fire
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Smoke
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Custom Volume Based Simulations
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Fog simulations
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Clouds
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VDB simulations
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