// Categorize the given inputPolygons as being inside/outside or (reverse-)aligned
// with the shape that is defined by the current brush or csg-branch.
// When an inputPolygon crosses the node, it is split into pieces and every individual
// piece is then categorized.
#region Categorize
public static void Categorize(CSGNode processedNode,
CSGMesh mesh,
CSGNode categorizationNode,
List <Polygon> inputPolygons,
List <Polygon> inside,
List <Polygon> aligned,
List <Polygon> revAligned,
List <Polygon> outside)
{
// When you go deep enough in the tree it's possible that all categories point to the same
// destination. So we detect that and potentially avoid a lot of wasted work.
if (inside == revAligned &&
inside == aligned &&
inside == outside)
{
inside.AddRange(inputPolygons);
return;
}
Restart:
if (processedNode == categorizationNode)
{
// When the currently processed node is the same node as we categorize against, then
// we know that all our polygons are visible and we set their default category
// (usually aligned, unless it's an instancing node in which case it's precalculated)
foreach (var polygon in inputPolygons)
{
switch (polygon.Category)
{
case PolygonCategory.Aligned: aligned.Add(polygon); break;
case PolygonCategory.ReverseAligned: revAligned.Add(polygon); break;
case PolygonCategory.Inside: inside.Add(polygon); break;
case PolygonCategory.Outside: outside.Add(polygon); break;
}
// When brushes overlap and they share the same surface area we only want to keep
// the polygons of the last brush in the tree, and skip all others.
// At this point in the tree we know that this polygon belongs to this brush, so
// we set it to visible. If the polygon is found to share the surface area with another
// brush further on in the tree it'll be set to invisible again in mesh.Intersect.
polygon.Visible = true;
}
return;
}
var leftNode = categorizationNode.Left;
var rightNode = categorizationNode.Right;
switch (categorizationNode.NodeType)
{
case CSGNodeType.Brush:
{
mesh.Intersect(categorizationNode.Bounds,
categorizationNode.Planes,
categorizationNode.Translation,
processedNode.Translation,
inputPolygons,
inside, aligned, revAligned, outside);
break;
}
case CSGNodeType.Addition:
{
// ( A || B)
var relativeLeftTrans = Vector3.Subtract(processedNode.Translation, leftNode.Translation);
var relativeRightTrans = Vector3.Subtract(processedNode.Translation, rightNode.Translation);
if (AABBi.IsOutside(processedNode.Bounds, relativeLeftTrans, leftNode.Bounds))
{
if (AABBi.IsOutside(processedNode.Bounds, relativeRightTrans, rightNode.Bounds))
{
// When our polygons lie outside the bounds of both the left and the right node, then
// all the polygons can be categorized as being 'outside'
outside.AddRange(inputPolygons);
}
else
{
//Categorize(processedNode, mesh, right,
// inputPolygons,
// inside, aligned, revAligned, outside);
categorizationNode = rightNode;
goto Restart;
}
}
else
if (AABBi.IsOutside(processedNode.Bounds, relativeRightTrans, rightNode.Bounds))
{
//Categorize(processedNode, left, mesh,
// inputPolygons,
// inside, aligned, revAligned, outside);
categorizationNode = leftNode;
goto Restart;
}
else
{
LogicalOr(processedNode, mesh, categorizationNode,
inputPolygons,
inside, aligned, revAligned, outside,
false, false);
}
break;
}
case CSGNodeType.Common:
{
// !(!A || !B)
var relativeLeftTrans = Vector3.Subtract(processedNode.Translation, leftNode.Translation);
var relativeRightTrans = Vector3.Subtract(processedNode.Translation, rightNode.Translation);
if (AABBi.IsOutside(processedNode.Bounds, relativeLeftTrans, leftNode.Bounds) ||
AABBi.IsOutside(processedNode.Bounds, relativeRightTrans, rightNode.Bounds))
{
// When our polygons lie outside the bounds of both the left and the right node, then
// all the polygons can be categorized as being 'outside'
outside.AddRange(inputPolygons);
}
else
{
LogicalOr(processedNode, mesh, categorizationNode,
inputPolygons,
outside, revAligned, aligned, inside,
true, true);
}
break;
}
case CSGNodeType.Subtraction:
{
// !(!A || B)
var relativeLeftTrans = Vector3.Subtract(processedNode.Translation, leftNode.Translation);
var relativeRightTrans = Vector3.Subtract(processedNode.Translation, rightNode.Translation);
if (AABBi.IsOutside(processedNode.Bounds, relativeLeftTrans, leftNode.Bounds))
{
// When our polygons lie outside the bounds of both the left node, then
// all the polygons can be categorized as being 'outside'
outside.AddRange(inputPolygons);
}
else
if (AABBi.IsOutside(processedNode.Bounds, relativeRightTrans, rightNode.Bounds))
{
categorizationNode = leftNode;
goto Restart;
}
else
{
LogicalOr(processedNode, mesh, categorizationNode,
inputPolygons,
outside, revAligned, aligned, inside,
true, false);
}
break;
}
}
}
public static void Categorize(CSGNode processedNode,
CSGMesh mesh,
CSGNode categorizationNode,
List<Polygon> inputPolygons,
List<Polygon> inside,
List<Polygon> aligned,
List<Polygon> revAligned,
List<Polygon> outside)
{
// When you go deep enough in the tree it's possible that all categories point to the same
// destination. So we detect that and potentially avoid a lot of wasted work.
if (inside == revAligned &&
inside == aligned &&
inside == outside)
{
inside.AddRange(inputPolygons);
return;
}
Restart:
if (processedNode == categorizationNode)
{
// When the currently processed node is the same node as we categorize against, then
// we know that all our polygons are visible and we set their default category
// (usually aligned, unless it's an instancing node in which case it's precalculated)
foreach (var polygon in inputPolygons)
{
switch (polygon.Category)
{
case PolygonCategory.Aligned: aligned.Add(polygon); break;
case PolygonCategory.ReverseAligned: revAligned.Add(polygon); break;
case PolygonCategory.Inside: inside.Add(polygon); break;
case PolygonCategory.Outside: outside.Add(polygon); break;
}
// When brushes overlap and they share the same surface area we only want to keep
// the polygons of the last brush in the tree, and skip all others.
// At this point in the tree we know that this polygon belongs to this brush, so
// we set it to visible. If the polygon is found to share the surface area with another
// brush further on in the tree it'll be set to invisible again in mesh.Intersect.
polygon.Visible = true;
}
return;
}
var leftNode = categorizationNode.Left;
var rightNode = categorizationNode.Right;
switch (categorizationNode.NodeType)
{
case CSGNodeType.Brush:
{
mesh.Intersect(categorizationNode.Bounds,
categorizationNode.Planes,
categorizationNode.Translation,
processedNode.Translation,
inputPolygons,
inside, aligned, revAligned, outside);
break;
}
case CSGNodeType.Addition:
{
// ( A || B)
var relativeLeftTrans = Vector3.Subtract(processedNode.Translation, leftNode.Translation);
var relativeRightTrans = Vector3.Subtract(processedNode.Translation, rightNode.Translation);
if (AABBi.IsOutside(processedNode.Bounds, relativeLeftTrans, leftNode.Bounds))
{
if (AABBi.IsOutside(processedNode.Bounds, relativeRightTrans, rightNode.Bounds))
{
// When our polygons lie outside the bounds of both the left and the right node, then
// all the polygons can be categorized as being 'outside'
outside.AddRange(inputPolygons);
}
else
{
//Categorize(processedNode, mesh, right,
// inputPolygons,
// inside, aligned, revAligned, outside);
categorizationNode = rightNode;
goto Restart;
}
}
else
if (AABBi.IsOutside(processedNode.Bounds, relativeRightTrans, rightNode.Bounds))
{
//Categorize(processedNode, left, mesh,
// inputPolygons,
// inside, aligned, revAligned, outside);
categorizationNode = leftNode;
goto Restart;
}
else
{
LogicalOr(processedNode, mesh, categorizationNode,
inputPolygons,
inside, aligned, revAligned, outside,
false, false);
}
break;
}
case CSGNodeType.Common:
{
// !(!A || !B)
var relativeLeftTrans = Vector3.Subtract(processedNode.Translation, leftNode.Translation);
var relativeRightTrans = Vector3.Subtract(processedNode.Translation, rightNode.Translation);
if (AABBi.IsOutside(processedNode.Bounds, relativeLeftTrans, leftNode.Bounds) ||
AABBi.IsOutside(processedNode.Bounds, relativeRightTrans, rightNode.Bounds))
{
// When our polygons lie outside the bounds of both the left and the right node, then
// all the polygons can be categorized as being 'outside'
outside.AddRange(inputPolygons);
}
else
{
LogicalOr(processedNode, mesh, categorizationNode,
inputPolygons,
outside, revAligned, aligned, inside,
true, true);
}
break;
}
case CSGNodeType.Subtraction:
{
// !(!A || B)
var relativeLeftTrans = Vector3.Subtract(processedNode.Translation, leftNode.Translation);
var relativeRightTrans = Vector3.Subtract(processedNode.Translation, rightNode.Translation);
if (AABBi.IsOutside(processedNode.Bounds, relativeLeftTrans, leftNode.Bounds))
{
// When our polygons lie outside the bounds of both the left node, then
// all the polygons can be categorized as being 'outside'
outside.AddRange(inputPolygons);
}
else
if (AABBi.IsOutside(processedNode.Bounds, relativeRightTrans, rightNode.Bounds))
{
categorizationNode = leftNode;
goto Restart;
}
else
{
LogicalOr(processedNode, mesh, categorizationNode,
inputPolygons,
outside, revAligned, aligned, inside,
true, false);
}
break;
}
}
}
