float implicitsurfacevel(<geometry>geometry, vector pos, vector &N, vector &vel)
<geometry>
When running in the context of a node (such as a wrangle SOP), this argument can be an integer representing the input number (starting at 0) to read the geometry from.
Alternatively, the argument can be a string specifying a geometry file (for example, a .bgeo) to read from. When running inside Houdini, this can be an op:/path/to/sop reference.
pos
The world-space position at which to evaluate the implicit surface.
N
Output unit normal, computed from the SDF gradient.
vel
Output surface velocity.
The velocity combines normal motion from dparm and interpolated rigid-body
motion from shape v/w attributes:
vel = grad * dparm + tangent(interpolated_rigid_velocity).
Returns
Signed distance to the implicit surface at pos.
This function requires the same implicit-surface attributes as
implicitsurface. For non-zero velocity, include per-shape
v, w, implicitsurfacedparms, and implicitsurfaceopdparms attributes.
Examples ¶
vector N; vector vel; float sdf = implicitsurfacevel(0, @P, N, vel);
| See also | |
| implicit | |
| sdf | |
| velocity |