pointConstraint

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This node implements a pointConstraint. Each constraint has a set of targets that are connected under the target attribute, a single constrained object that is connected to the constraint* attributes, and possibly other information to help compute the correct results. In the case of the pointConstraint, the extra information is stored in offset and constraintOffsetPolarity attributes.

The pointConstraint node can have any number of target inputs. Each target is connected to attributes inside a single element of the target attribute. For example, the first target object would be connected elements of target[0], the second target object would be connected to elements of target[1], etc. The elements of each target are: targetTranslate, targetRotatePivot, targetRotateTranslate, targetParentMatrix, and targetWeight.

The elements of each target are normally connected to the target objects as follows:

pointConstraint attribute	connected to
targetTranslate	translate
targetRotatePivot	rotatePivot
targetRotateTranslate	rotatePivotTranslate
targetParentMatrix	parentMatrix[i]
targetWeight	set to 1.0

The targetWeight attribute is not generally connected to the target object. Instead, it may be animated by other means to adjust the weighted average computation for the target point.

The pointConstraint node uses these inputs to compute the world space position of the pivot point of each target object. It then computes a weighted average of the these pivot points. This weighted average is called the target point.

The constrained object is connected to the constraint* attributes. For a pointConstraint, the constraintRotatePivot, constraintRotateTranslate, and constraintParentInverseMatrix are inputs to the pointConstraint. The attribute constraintTranslate is the only output.

The pointConstraint node computes an output translation value such that the pivot point of the constrained object is offset by offset * constraintOffsetPolarity from the target point.

Although the all the constraint nodes inherit from transform, they do not actively use any of the attributes from transform.

aimConstraint, geometryConstraint, orientConstraint, normalConstraint, parentConstraint, poleVectorConstraint, scaleConstraint, tangentConstraint, lookAt

constraintOffsetPolarity, constraintParentInverseMatrix, constraintRotatePivot, constraintRotatePivotX, constraintRotatePivotY, constraintRotatePivotZ, constraintRotateTranslate, constraintRotateTranslateX, constraintRotateTranslateY, constraintRotateTranslateZ, constraintTranslate, constraintTranslateX, constraintTranslateY, constraintTranslateZ, offset, offsetX, offsetY, offsetZ, restTranslate, restTranslateX, restTranslateY, restTranslateZ, target, targetParentMatrix, targetRotatePivot, targetRotatePivotX, targetRotatePivotY, targetRotatePivotZ, targetRotateTranslate, targetRotateTranslateX, targetRotateTranslateY, targetRotateTranslateZ, targetTranslate, targetTranslateX, targetTranslateY, targetTranslateZ, targetWeight

Long name (short name)	Type	Default	Flags
target (tg)	compound	n/a
bundle of matrix, input position, and weight
targetTranslate (tt) double3 input translation targetTranslateX (ttx) distance (double) 0.0cm input X translation targetTranslateY (tty) distance (double) 0.0cm input Y translation targetTranslateZ (ttz) distance (double) 0.0cm input Z translation
targetRotatePivot (trp) double3 input rotate pivot targetRotatePivotX (trpx) distance (double) 0.0cm input X rotate pivot targetRotatePivotY (trpy) distance (double) 0.0cm input Y rotate pivot targetRotatePivotZ (trpz) distance (double) 0.0cm input Z rotate pivot
targetRotateTranslate (trt) double3 input rotate pivot translate targetRotateTranslateX (trtx) distance (double) 0.0cm input X rotate pivot translate targetRotateTranslateY (trty) distance (double) 0.0cm input Y rotate pivot translate targetRotateTranslateZ (trtz) distance (double) 0.0cm input Z rotate pivot translate
targetParentMatrix (tpm) matrix identity input world position
targetWeight (tw) double 1.0 input weight for the position
constraintParentInverseMatrix (cpim)	matrix	identity
inverse of the parent matrix of the object
constraintRotatePivot (crp)	double3
object rotate pivot
constraintRotatePivotX (crpx) distance (double) 0.0cm object X rotate pivot
constraintRotatePivotY (crpy) distance (double) 0.0cm object Y rotate pivot
constraintRotatePivotZ (crpz) distance (double) 0.0cm object Z rotate pivot
constraintRotateTranslate (crt)	double3
object rotate pivot translate
constraintRotateTranslateX (crtx) distance (double) 0.0cm object X rotate pivot translate
constraintRotateTranslateY (crty) distance (double) 0.0cm object Y rotate pivot translate
constraintRotateTranslateZ (crtz) distance (double) 0.0cm object Z rotate pivot translate
offset (o)	double3
object offset
offsetX (ox) distance (double) 0.0cm object X offset
offsetY (oy) distance (double) 0.0cm object Y offset
offsetZ (oz) distance (double) 0.0cm object Z offset
constraintOffsetPolarity (cop)	double	1
This is a scalar value by which the offset vector is multiplied, allowing you to animate or tweak the constrained object's offset from its targets by adjusting this single value. The overall offset is equal to constraintOffsetPolarity times the offset vector.
constraintTranslate (ct)	double3	0.0, 0.0, 0.0
output point position
constraintTranslateX (ctx) distance (double) 0.0cm output X point position
constraintTranslateY (cty) distance (double) 0.0cm output Y point position
constraintTranslateZ (ctz) distance (double) 0.0cm output Z point position
restTranslate (rst)	double3	0.0, 0.0, 0.0
The rest translation defines the output of the constraint when all weights are zero. It is used when the enableRestPosition attribute is true.
restTranslateX (rtx) distance (double) 0.0cm rest x translation
restTranslateY (rty) distance (double) 0.0cm rest y translation
restTranslateZ (rtz) distance (double) 0.0cm rest z translation