NAME

GDX_FACE - Face

GENERAL DESCRIPTION

A GDX Face entity is a collection of GDX Loop entities that form a bounded face.

DDF SPECIFICATION

entity 46:0 GDX_FACE "Face" {





char
SURF_SENSE;





ptr
SURF
reftype = (P_SURFS);





char
FIRST_IS_OUTER;





count
NUM_OF_LOOPS;





struct
LOOPS[NUM_OF_LOOPS] {





char
SENSE;





ptr
LOOP
reftype = (44:0 /* GDX_LOOP */);





};




};

FIELD DESCRIPTIONS

SURF_SENSE

Flag indicating if the normal of the surface agrees with normal of the face.

PDX_TRUE

The surface normal and face normal agree

PDX_TRUE

The surface normal and face normal disagree

SURF

Database pointer to GDX surface entity.

FIRST_IS_OUTER

The first is the outer loop.

PDX_TRUE

The first loop is the outer boundary of the face

PDX_FALSE

The first loop may be the outter boundary of the face. The face may not have an outer loop. .RE

NUM_OF_LOOPS

The number of loops in the GDX Face.

LOOPS

Array, dimensioned to [NUM_OF_LOOPS], of structures containing loop sense and loop database pointer information.

SENSE

Flag indicating whether the sense of this boundary of the GDX Face agrees with or opposes that of the corresponding GDX Loop defined by the LOOP field.

PDX_TRUE

The sense of this boundary of the face agrees with the defining GDX Loop

PDX_FALSE

The sense of this boundary of the solid disagrees with the defining GDX Loop

LOOP

The database pointer of the GDX Loop.

Restrictions

The GDX Face is subject to the following restrictions: NUM_OF_LOOPS > 0