public bool UpdateCapture(ITransformable target, Ray worldRay)
{
// ray-hit with plane that contains translation axis
Vector3 planeHit = raycastFrame.RayPlaneIntersection(worldRay.origin, worldRay.direction, 2);
// figure out new T-value along axis, then our translation update is delta-t
float fNewT = MathUtil.ClosestPointOnLineT(translateFrameW.Origin, translateAxisW, planeHit);
float fDeltaT = (fNewT - fTranslateStartT);
// construct new frame translated along axis (in local space)
Frame3 newFrame = translateFrameL;
newFrame.Origin += fDeltaT * translateFrameL.GetAxis(nTranslationAxis);
// update target
target.SetLocalFrame(newFrame, CoordSpace.ObjectCoords);
return(true);
}
float fTranslateStartT; // start T-value along translateAxisW
public bool BeginCapture(ITransformable target, Ray worldRay, UIRayHit hit)
{
// save local and world frames
translateFrameL = target.GetLocalFrame(CoordSpace.ObjectCoords);
translateFrameW = target.GetLocalFrame(CoordSpace.WorldCoords);
translateAxisW = translateFrameW.GetAxis(nTranslationAxis);
// save t-value of closest point on translation axis, so we can find delta-t
Vector3 vWorldHitPos = hit.hitPos;
fTranslateStartT = MathUtil.ClosestPointOnLineT(
translateFrameW.Origin, translateAxisW, vWorldHitPos);
// construct plane we will ray-intersect with in UpdateCapture()
Vector3 vForward = Vector3.Cross(Camera.main.transform.up, translateAxisW);
raycastFrame = new Frame3(vWorldHitPos, vForward);
return(true);
}
