BRL-CAD
Data Fields
rt_metaball_internal Struct Reference
librt (Geometry I/O, Raytracing) » Geometry Primitives » Metaball

#include <geom.h>

Collaboration diagram for rt_metaball_internal:
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Data Fields

uint32_t magic
 
int method
 
fastf_t threshold
 
fastf_t initstep
 
fastf_t finalstep
 
struct bu_list metaball_ctrl_head
 

Detailed Description

ID_METABALL

The "metaball" primitive contains a method ID, threshold value, and an unordered set of control points. Each control point contains a 3d location, a "field strength", and possibly a "blobbiness" value (called "goo" in rt_metaball_add_point).

There are three method ID's defined:

  1. "metaball", which is the Tokyo Metaball approximation of the Blinn Blobby Surface. This method is not implemented yet.
  2. "blob", the Blinn method.
  3. "iso", which is a simple computation like you'd see for computing gravitational magnitude or point charge in a basic physics course. Blending function in latex notation is:
\Sum_{i}\frac{f_{i}}{d^{2}}

The surface of the primitive exists where the summation of the points contribution is equal to the threshold, with the general fldstr/distance^2 pattern.

The blobbiness value is only used in the blob method, and modifies the gusseting effect.

Definition at line 156 of file geom.h.

Field Documentation

◆ magic

uint32_t magic

Definition at line 157 of file geom.h.

◆ method

int method

Definition at line 162 of file geom.h.

◆ threshold

fastf_t threshold

Definition at line 163 of file geom.h.

◆ initstep

fastf_t initstep

Definition at line 164 of file geom.h.

◆ finalstep

fastf_t finalstep

Definition at line 165 of file geom.h.

◆ metaball_ctrl_head

struct bu_list metaball_ctrl_head

Definition at line 166 of file geom.h.

The documentation for this struct was generated from the following file: