public bool Select(Shape parentShape, Shape componentShape, SemanticSelector selector)
{
var componentShapeType = componentShape.GetType();
if (componentShapeType != typeof(Quad))
{
throw new ArgumentException($"'{nameof(Box)}' cannot have a '{componentShapeType.Name}' as a component");
}
var cN = componentShape.Transform.GetZAxis();
switch (selector)
{
case SemanticSelector.BOTTOM:
{
var pY = parentShape.Transform.GetYAxis();
var dot = Vector3.Dot(pY, cN);
return(dot <= -_DotThreshold); /* Y and N are almost parallel and point to same direction */
}
case SemanticSelector.TOP:
{
var pY = parentShape.Transform.GetYAxis();
var dot = Vector3.Dot(pY, cN);
return(dot >= _DotThreshold); /* Y and N are almost parallel and point to opposite directions */
}
case SemanticSelector.BACK:
{
var pZ = parentShape.Transform.GetZAxis();
var dot = Vector3.Dot(pZ, cN);
return(dot <= -_DotThreshold); /* Z and N are almost parallel and point to same direction */
}
case SemanticSelector.FRONT:
{
var pZ = parentShape.Transform.GetZAxis();
var dot = Vector3.Dot(pZ, cN);
return(dot >= _DotThreshold); /* Z and N are almost parallel and point to opposite directions */
}
case SemanticSelector.RIGHT:
{
var pX = parentShape.Transform.GetXAxis();
var dot = Vector3.Dot(pX, cN);
return(dot >= _DotThreshold); /* X and N are almost parallel and point to same direction */
}
case SemanticSelector.LEFT:
{
var pX = parentShape.Transform.GetXAxis();
var dot = Vector3.Dot(pX, cN);
return(dot <= -_DotThreshold); /* X and N are almost parallel and point to opposite directions */
}
case SemanticSelector.HORIZONTAL:
{
var pY = parentShape.Transform.GetYAxis();
var absDot = Math.Abs(Vector3.Dot(pY, cN));
return(absDot >= _DotThreshold); /* Y and N are almost parallel */
}
case SemanticSelector.VERTICAL:
case SemanticSelector.SIDE:
{
var pY = parentShape.Transform.GetYAxis();
var absDot = Math.Abs(Vector3.Dot(pY, cN));
return(absDot <= _Epsilon); /* Y and N are almost perpendicular */
}
case SemanticSelector.ALL:
return(true); /* permissive */
default:
throw new Exception($"Unknown {nameof(SemanticSelector)}: '{selector.ToString()}'");
}
}
public ComponentSplitArg(SemanticSelector selector, ISymbol successor)
{
Selector = selector;
Successor = successor ?? throw new ArgumentNullException(nameof(successor));
}