jv.geom

Class PgBndConstraint

• All Implemented Interfaces:
java.io.Serializable, java.lang.Cloneable, PsUpdateIf

public class PgBndConstraint
extends PsObject
Descriptor for boundary constraints used in variational problems. The member variables have different meanings depending on the shape of the boundary curve. The following describes their meaning and shows how to generate a curve for given constraints.

if (hasShape(FIX_STRAIGHT)) {
// m_start     = start point on line;
// m_end       = end point on line;
// m_dir       = unit length direction of line;
// To compute the line:
for (j=0; j<bndLen; j++) {
v = (double)j / (double)(bndLen-1.);
m_vertex[j].blend(1.-v, p, v, q);
}
// To constrain the line:
for (j=0; j<bndLen; j++) {
m_vertex[j].projectPointToLine(m_vertex[j], m_start, m_dir);
}
} else if (hasShape(FIX_PLANE)) {
// m_start     = start point of planar curve;
// m_end       = end point of planar curve;
// m_dir       = unit length normal of plane;
// m_startDir  = direction along m_start may vary;
// m_endDir    = direction along m_end may vary;
// m_startDir and m_endDir are addtn'l contraints depending on the adjacent boundaries
// Each vector determines a line along which the corresponding start and end point
// is allowed to vary. This is used if either of the two adjacent boundary curves
// is of type FIX_PLANE too.
// Both vectors might be null if boundary curve is closed.
// To compute the plane:
// To constrain the line:
for (j=0; j<bndLen; j++) {
m_vertex[j].projectPointToPlane(m_vertex[j], m_start, m_dir);
}
} else if (hasShape(FIX_CIRCLE)) {
// m_start     = start point on circle;
// m_end       = end point on circle;
// m_vec1      = mid point of circle;
// m_vec2      = orient, i.e. normal of circle;
// To compute the circle:
for (j=0; j<bndLen; j++) {
v = (double)j / (double)(bndLen-1.);
m_vertex[j].evalCircle(mid, orient, start, end, v);
}
// To constrain the circle:
for (j=0; j<bndLen; j++) {
}
} else if (hasShape(FIX_HELIX)) {
// m_start     = start point on helix;
// m_end       = end point on helix;
// m_vec1      = axis bottom of helix;
// m_vec2      = axis direction of helix;
// To compute the helix:
for (j=0; j<bndLen; j++) {
v = (double)j / (double)(bndLen-1.);
m_vertex[j].evalHelix(bot, axisDir, start, end, v);
}
else if (m_bndShapeBits[anInd].get(PgBndConstraint.FIX_SPLINE)) {
// m_start     = start point on spline;
// m_end       = end point on spline;
// m_vec1      = tangent of spline at start point;
// m_vec2      = tangent of spline at end point;
// To compute the spline:
for (j=0; j<bndLen; j++) {
v = (double)j / (double)(bndLen-1.);
m_vertex[j].evalSpline(m_vec1, m_vec2, m_start, m_end, v);
}
}

Serialized Form
• Field Detail

• FIX_CURVE

public static final int FIX_CURVE
Vertices are fixed, i.e. Dirichlet conditions.
Constant Field Values
• FIX_STRAIGHT

public static final int FIX_STRAIGHT
Vertices are constrained to a straight line.
Constant Field Values
• FIX_PLANE

public static final int FIX_PLANE
Vertices are constrained to a plane.
Constant Field Values

Distance between vertices is fixed, i.e. the thread of constant length.
Constant Field Values
• FIX_CIRCLE

public static final int FIX_CIRCLE
Vertices are constrained to lie on a circle. Not yet supported by *bd files and JavaView.
Constant Field Values
• FIX_HELIX

public static final int FIX_HELIX
Vertices are constrained to lie on a helix. Not yet supported by *bd files and JavaView.
Constant Field Values
• FIX_POLYGON

public static final int FIX_POLYGON
Vertices are constrained to lie on a polygon. Not yet supported by *bd files and JavaView.
Constant Field Values
• m_start

public PdVector m_start
Start point of boundary, first vertex.
• m_end

public PdVector m_end
End point of boundary, last vertex.
• m_vec1

public PdVector m_vec1
Additional control vertex, meaning depends on current shape.
• m_vec2

public PdVector m_vec2
Additional control vertex, meaning depends on current shape.
• m_dir

public PdVector m_dir
Unit direction of constraining line or unit normal of constraining plane.
• m_startDir

public PdVector m_startDir
Special constraint for the first point of boundary, for example, two adjacent planar curves force the common vertex to lie on the straight line along which both plane intersect. If this instance variable is null, then there is no constraint.
• m_endDir

public PdVector m_endDir
Special constraint for the last point of boundary, for example, two adjacent planar curves force the common vertex to lie on the straight line along which both plane intersect. If this instance variable is null, then there is no constraint.
• Constructor Detail

• PgBndConstraint

public PgBndConstraint(int dim)
• Method Detail

• init

public void init()
Initializes and resets instance.
Overrides:
init in class PsObject
• clone

public java.lang.Object clone()
Duplicate geometry by recursively cloning all instance variables except inspector panels and lists of registered listeners. The parent relationship is maintained only within this class but not to external classes. In general, all links of the clone to external objects are set to null.

Display list is not cloned but set to null. Method menu is cloned.

Overrides:
clone in class PsObject
copy(PsObject)
• copy

public void copy(PsObject object)
Copy argument object into this object by recursively copying all instance variables.
Overrides:
copy in class PsObject
PsObject.clone()
• applyModelingMatrix

public boolean applyModelingMatrix(PdMatrix modelMatrix)
Multiply the modeling matrix to all vertices and vectors. The modeling matrix of this geometry is set to the identity matrix.
Returns:
true if operation was applied successfully.
Since:
JavaView 2.36
• clearShape

public void clearShape(int aBit)
Remove shape constraint. For possible shapes see PgBndConstraint.
• hasShape

public boolean hasShape(int aBit)
Check whether shape constraint is set. For possible shapes see PgBndConstraint.
• setShape

public void setShape(int aBit)
Set shape constraint. For possible shapes see PgBndConstraint.
• setShape

public void setShape(java.util.BitSet shape)
setShape(int)
• toString

public java.lang.String toString()
Create a multi-line string representation with detailed information about all instance variables.
Overrides:
toString in class PsObject
• getDim

public int getDim()
Get dim of vertex constraints.