public LoopIterator(MyPolygon poly, int loopBegin)
{
m_data = poly.m_vertices;
m_begin = loopBegin;
m_currentIndex = -1;
m_current = new Vertex();
m_current.Next = m_begin;
}
public LoopIterator(MyPolygon poly, int loopBegin)
{
m_data = poly.m_vertices;
m_begin = loopBegin;
m_currentIndex = -1;
m_current = new Vertex();
m_current.Next = m_begin;
}
public BoundPair(MyPolygon parent, int left, int minimum, int right, bool rightHorizontal)
{
Debug.Assert(parent != null);
Parent = parent;
Left = left;
Minimum = minimum;
Right = right;
RightIsPrecededByHorizontal = rightHorizontal;
m_minimumCoordinate = 0;
}
private void PrepareTransforms(MyPolygon polyA)
{
m_projectionPlane = polyA.PolygonPlane;
Vector3 origin = -polyA.PolygonPlane.Normal * polyA.PolygonPlane.D;
Vector3 forward = polyA.PolygonPlane.Normal;
Vector3 right = Vector3.CalculatePerpendicularVector(forward);
Vector3 up = Vector3.Cross(right, forward);
m_invProjectionTransform = Matrix.CreateWorld(origin, forward, up);
Matrix.Invert(ref m_invProjectionTransform, out m_projectionTransform);
}
private void ProjectPoly(MyPolygon input, MyPolygon output, ref Matrix projection)
{
for (int i = 0; i < input.LoopCount; ++i)
{
m_tmpList.Clear();
var iterator = input.GetLoopIterator(i);
while (iterator.MoveNext())
{
Vector3 transformed = Vector3.Transform(iterator.Current, projection);
m_tmpList.Add(transformed);
}
output.AddLoop(m_tmpList);
}
}
public MyPolygon Difference(MyPolygon polyA, MyPolygon polyB)
{
return PerformBooleanOperation(polyA, polyB, m_operationDifference);
}
private MyPolygon PerformBooleanOperation(MyPolygon polyA, MyPolygon polyB, Operation operation)
{
Debug.Assert(polyA.PolygonPlane.Equals(polyB.PolygonPlane));
Clear();
PrepareTransforms(polyA);
ProjectPoly(polyA, m_polyA, ref m_projectionTransform);
ProjectPoly(polyB, m_polyB, ref m_projectionTransform);
m_operation = operation;
PerformInPlane();
m_operation = null;
return UnprojectResult();
}
private static MatrixD DebugDrawBoundList(MatrixD drawMatrix, MyPolygon drawPoly, List<BoundPair> boundList)
{
foreach (var bound in boundList)
{
MyPolygon.Vertex v1, v2;
Vector3 vec1 = default(Vector3);
Vector3 vec2 = default(Vector3);
int prev = bound.Left;
drawPoly.GetVertex(prev, out v1);
int current = v1.Prev;
while (prev != bound.Minimum)
{
drawPoly.GetVertex(current, out v2);
vec1 = Vector3.Transform(v1.Coord, drawMatrix);
vec2 = Vector3.Transform(v2.Coord, drawMatrix);
MyRenderProxy.DebugDrawLine3D(vec1, vec2, Color.Red, Color.Red, false);
prev = current;
v1 = v2;
current = v1.Prev;
}
MatrixD minimum = drawMatrix;
minimum.Translation = vec2;
MyRenderProxy.DebugDrawAxis(minimum, 0.25f, false);
MyRenderProxy.DebugDrawSphere(vec2, 0.03f, Color.Yellow, 1.0f, false);
prev = bound.Minimum;
drawPoly.GetVertex(prev, out v1);
current = v1.Prev;
while (prev != bound.Right)
{
drawPoly.GetVertex(current, out v2);
vec1 = Vector3.Transform(v1.Coord, drawMatrix);
vec2 = Vector3.Transform(v2.Coord, drawMatrix);
MyRenderProxy.DebugDrawLine3D(vec1, vec2, Color.Green, Color.Green, false);
prev = current;
v1 = v2;
current = v1.Prev;
}
if (bound.RightIsPrecededByHorizontal)
{
MyRenderProxy.DebugDrawSphere(vec2, 0.03f, Color.Red, 1.0f, false);
}
}
return drawMatrix;
}
public MyPolygon Union(MyPolygon polyA, MyPolygon polyB)
{
return PerformBooleanOperation(polyA, polyB, m_operationUnion);
}
private MyPolygon UnprojectResult()
{
MyPolygon tmp = new MyPolygon(new Plane(Vector3.Forward, 0));
MyPolygon result = new MyPolygon(m_projectionPlane);
foreach (var poly in m_results)
{
poly.Postprocess();
var loop = poly.GetLoop();
if (loop.Count == 0) continue;
tmp.AddLoop(poly.GetLoop());
}
ProjectPoly(tmp, result, ref m_invProjectionTransform);
return result;
}
private static int FindLoopLocalMaximum(MyPolygon poly, int loop)
{
int index, maxIndex;
Vector3 localMax;
MyPolygon.Vertex vertex, otherVertex;
index = poly.GetLoopStart(loop);
poly.GetVertex(index, out vertex);
maxIndex = index;
localMax = vertex.Coord;
// Find local maximum while going to the previous vertices in the loop
index = vertex.Prev;
poly.GetVertex(index, out otherVertex);
while (otherVertex.Coord.Y > localMax.Y || (otherVertex.Coord.Y == localMax.Y && otherVertex.Coord.X > localMax.X))
{
maxIndex = index;
localMax = otherVertex.Coord;
index = otherVertex.Prev;
poly.GetVertex(index, out otherVertex);
}
// Find local maximum while going to the next vertices in the loop
index = vertex.Next;
poly.GetVertex(index, out otherVertex);
while (otherVertex.Coord.Y > localMax.Y || (otherVertex.Coord.Y == localMax.Y && otherVertex.Coord.X > localMax.X))
{
maxIndex = index;
localMax = otherVertex.Coord;
index = otherVertex.Next;
poly.GetVertex(index, out otherVertex);
}
return maxIndex;
}
private static void ConstructBoundPairs(MyPolygon poly, List<BoundPair> boundList)
{
for (int l = 0; l < poly.LoopCount; ++l)
{
int start, current, prev;
MyPolygon.Vertex vertex;
start = FindLoopLocalMaximum(poly, l);
poly.GetVertex(start, out vertex);
current = start;
MyPolygon.Vertex otherVertex;
poly.GetVertex(vertex.Prev, out otherVertex);
BoundPair bounds = new BoundPair(poly, -1, -1, start, otherVertex.Coord.Y == vertex.Coord.Y);
bool right = true;
int comparison, prevComparison;
comparison = -1;
do
{
Vector3 prevCoord = vertex.Coord;
prev = current;
current = vertex.Next;
poly.GetVertex(current, out vertex);
prevComparison = comparison;
comparison = CompareCoords(vertex.Coord, prevCoord);
Debug.Assert(comparison != 0, "Duplicate vertex in input polygon!");
if (right)
{
if (comparison > 0)
{
bounds.Minimum = prev;
right = false;
}
}
else
{
if (comparison < 0)
{
bounds.Left = prev;
Debug.Assert(bounds.IsValid());
boundList.Add(bounds);
bounds = new BoundPair(poly, -1, -1, prev, prevComparison == 0);
right = true;
}
}
} while (current != start);
bounds.Left = current;
Debug.Assert(right == false);
Debug.Assert(bounds.IsValid());
boundList.Add(bounds);
}
}
private void RecalculateActiveEdge(ref Edge edge, ref MyPolygon.Vertex lowerVertex, ref MyPolygon.Vertex upperVertex, Side boundPairSide)
{
float Dy = upperVertex.Coord.Y - lowerVertex.Coord.Y;
float Dx = upperVertex.Coord.X - lowerVertex.Coord.X;
Debug.Assert(Dx != 0.0f || Dy != 0.0f, "Invalid polygon! Right point and minimum of a bound were the same point!");
edge.TopVertexIndex = boundPairSide == Side.LEFT ? lowerVertex.Next : lowerVertex.Prev;
edge.BottomX = lowerVertex.Coord.X;
edge.TopY = upperVertex.Coord.Y;
edge.DXdy = Dy == 0 ? Dx : Dx / Dy;
InsertScanBeamDivide(upperVertex.Coord.Y);
}
private Edge PrepareActiveEdge(int boundPairIndex, ref MyPolygon.Vertex lowerVertex, ref MyPolygon.Vertex upperVertex, PolygonType polyType, Side side)
{
Edge newEdge = new Edge();
newEdge.BoundPairIndex = boundPairIndex;
newEdge.BoundPairSide = side;
newEdge.Kind = polyType;
if (polyType == PolygonType.CLIP)
{
newEdge.OutputSide = m_operation.ClipInvert ? OtherSide(side) : side;
}
else
{
newEdge.OutputSide = m_operation.SubjectInvert ? OtherSide(side) : side;
}
RecalculateActiveEdge(ref newEdge, ref lowerVertex, ref upperVertex, side);
return newEdge;
}