rt_metaball_internal Struct Reference

#include <geom.h>

Collaboration diagram for rt_metaball_internal:

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" (weight of the point's contribution), and a "blobbiness" parameter (the beta/negative-exponent coefficient used in the Blinn blobby-surface formula).

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{field\_strength_{i}}{d^{2}}

The surface of the primitive exists where the summation of the points' contributions equals the threshold.

The blobbiness value is only used in the blob method, and modifies the gusseting effect (Blinn's beta coefficient).

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.

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

• include/rt/geom.h