/**
* Internal function for moving the object along the path.
* Generally this function is called automatically by <code>preUpdate()</code>.
* The first half of the function decides if the object can advance to the next node in the path,
* while the second half handles actually picking a velocity toward the next node.
*/
protected void updatePathMotion()
{
//first check if we need to be pointing at the next node yet
_point.x = x + width * 0.5f;
_point.y = y + height * 0.5f;
FlxPoint node = path.nodes[_pathNodeIndex];
float deltaX = node.x - _point.x;
float deltaY = node.y - _point.y;
bool horizontalOnly = (_pathMode & PATH_HORIZONTAL_ONLY) > 0;
bool verticalOnly = (_pathMode & PATH_VERTICAL_ONLY) > 0;
if (horizontalOnly)
{
if (((deltaX > 0)?deltaX:-deltaX) < pathSpeed * FlxG.elapsed)
{
node = advancePath();
}
}
else if (verticalOnly)
{
if (((deltaY > 0)?deltaY:-deltaY) < pathSpeed * FlxG.elapsed)
{
node = advancePath();
}
}
else
{
if (Math.Sqrt(deltaX * deltaX + deltaY * deltaY) < pathSpeed * FlxG.elapsed)
{
node = advancePath();
}
}
//then just move toward the current node at the requested speed
if (pathSpeed != 0)
{
//set velocity based on path mode
_point.x = x + width * 0.5f;
_point.y = y + height * 0.5f;
if (horizontalOnly || (_point.y == node.y))
{
velocity.x = (_point.x < node.x)?pathSpeed:-pathSpeed;
if (velocity.x < 0)
{
pathAngle = -90;
}
else
{
pathAngle = 90;
}
if (!horizontalOnly)
{
velocity.y = 0;
}
}
else if (verticalOnly || (_point.x == node.x))
{
velocity.y = (_point.y < node.y)?pathSpeed:-pathSpeed;
if (velocity.y < 0)
{
pathAngle = 0;
}
else
{
pathAngle = 180;
}
if (!verticalOnly)
{
velocity.x = 0;
}
}
else
{
pathAngle = FlxU.getAngle(_point, node);
FlxU.rotatePoint(0, pathSpeed, 0, 0, pathAngle, velocity);
}
//then set object rotation if necessary
if (_pathRotate)
{
angularVelocity = 0;
angularAcceleration = 0;
angle = pathAngle;
}
}
}
