void Transforms::setDirection(const Vector3& vec, tTransformSpace relativeTo,
const Vector3& localDirectionVector)
{
// Do nothing if given a zero vector
if (vec == Vector3::ZERO)
return;
// The direction we want the local direction point to
Vector3 targetDir = vec.normalisedCopy();
// Retrieve the parent transforms of this component
Transforms* pParentTransforms = getTransforms();
// Transform target direction to world space
switch (relativeTo)
{
case TS_LOCAL:
targetDir = getWorldOrientation() * targetDir;
break;
case TS_PARENT:
if (m_bInheritOrientation && pParentTransforms)
targetDir = pParentTransforms->getWorldOrientation() * targetDir;
break;
case TS_WORLD:
// default orientation
break;
}
// Calculate target orientation relative to world space
Quaternion targetOrientation;
// Get current local direction relative to world space
const Quaternion& currentOrient = getWorldOrientation();
Vector3 currentDir = currentOrient * localDirectionVector;
if ((currentDir + targetDir).squaredLength() < 0.00005f)
{
// Oops, a 180 degree turn (infinite possible rotation axes)
// Default to yaw i.e. use current UP
targetOrientation =
Quaternion(-currentOrient.y, -currentOrient.z, currentOrient.w, currentOrient.x);
}
else
{
// Derive shortest arc to new direction
Quaternion rotQuat = currentDir.getRotationTo(targetDir);
targetOrientation = rotQuat * currentOrient;
}
// Set target orientation, transformed to parent space
if (pParentTransforms && m_bInheritOrientation)
setOrientation(pParentTransforms->getWorldOrientation().UnitInverse() * targetOrientation);
else
setOrientation(targetOrientation);
}
void Transforms::translate(const Vector3& d, tTransformSpace relativeTo)
{
Vector3 adjusted;
switch(relativeTo)
{
case TS_LOCAL:
// Position is relative to parent so transform downwards
m_position += m_orientation * d;
break;
case TS_PARENT:
m_position += d;
break;
case TS_WORLD:
{
// Position is relative to parent so transform upwards
Transforms* pParent = getTransforms();
if (pParent)
m_position += (pParent->getWorldOrientation().Inverse() * d) / pParent->getWorldScale();
else
m_position += d;
break;
}
}
needUpdate();
}
void Body::getWorldTransform(btTransform& worldTrans) const
{
Transforms* pTransforms = getTransforms();
if (pTransforms)
{
worldTrans = btTransform(toBullet(pTransforms->getWorldOrientation()),
toBullet(pTransforms->getWorldPosition()));
}
}
Handle<Value> Transforms_GetWorldOrientation(Local<String> property, const AccessorInfo &info)
{
HandleScope handle_scope;
Transforms* ptr = GetPtr(info.This());
assert(ptr);
return handle_scope.Close(toJavaScript(ptr->getWorldOrientation()));
}
void Body::setWorldTransform(const btTransform& worldTrans)
{
Transforms* pTransforms = getTransforms();
if (pTransforms)
{
pTransforms->translate(fromBullet(worldTrans.getOrigin()) - pTransforms->getWorldPosition(), Transforms::TS_WORLD);
if (m_bRotationEnabled)
pTransforms->rotate(pTransforms->getWorldOrientation().rotationTo(fromBullet(worldTrans.getRotation())), Transforms::TS_WORLD);
}
}
void Transforms::update()
{
if (!m_bDirty)
return;
Transforms* pParent = getTransforms();
if (pParent)
{
// Update orientation
const Quaternion& parentOrientation = pParent->getWorldOrientation();
if (m_bInheritOrientation)
{
// Combine orientation with that of parent
m_fullOrientation = parentOrientation * m_orientation;
m_fullOrientation.normalise();
}
else
{
// No inheritence
m_fullOrientation = m_orientation;
}
// Update scale
const Vector3& parentScale = pParent->getWorldScale();
if (m_bInheritScale)
{
// Scale own position by parent scale, NB just combine
// as equivalent axes, no shearing
m_fullScale = parentScale * m_scale;
}
else
{
// No inheritence
m_fullScale = m_scale;
}
// Change position vector based on parent's orientation & scale
m_fullPosition = parentOrientation * (parentScale * m_position);
// Add altered position vector to parents
m_fullPosition += pParent->getWorldPosition();
}
else
{
// No parent
m_fullPosition = m_position;
m_fullOrientation = m_orientation;
m_fullScale = m_scale;
}
m_bDirty = false;
}