//--------------------------------------------------------------
#region Methods
//--------------------------------------------------------------
/// <inheritdoc/>
internal override void Flatten(ArrayList <Vector3F> vertices, ArrayList <int> strokeIndices, ArrayList <int> fillIndices)
{
Triangulator triangulator = null;
var segmentVertices = ResourcePools <Vector2F> .Lists.Obtain();
var segmentStartIndices = ResourcePools <int> .Lists.Obtain();
Vector2F previousVertex = new Vector2F(float.NaN);
foreach (var curve in Segments)
{
segmentVertices.Clear();
curve.Flatten(segmentVertices, MaxNumberOfIterations, Tolerance);
// Flatten should always return an even number of vertices. But if Flatten()
// is erroneous we simply ignore the last vertex.
int vertexCount = segmentVertices.Count;
if (vertexCount % 2 != 0)
{
vertexCount--;
}
if (vertexCount < 2)
{
continue;
}
Vector2F segmentStartVertex = segmentVertices[0];
bool isNewShape;
int segmentStartIndex; // Start of current segment in 'vertices'.
if (segmentStartVertex == previousVertex)
{
// Continuation of current shape: Skip first vertex of segment.
isNewShape = false;
segmentStartIndex = vertices.Count - 1;
}
else
{
// Start of new shape: Previous segments are no longer needed.
isNewShape = true;
segmentStartIndices.Clear();
segmentStartIndex = vertices.Count;
}
// Check for closed shapes.
Vector2F segmentEndVertex = segmentVertices[segmentVertices.Count - 1];
bool isClosedShape = false;
int shapeStartIndex = -1;
// Check if current segment is closed.
if (vertexCount > 2 && segmentStartVertex == segmentEndVertex)
{
// Closed shape found.
isClosedShape = true;
shapeStartIndex = segmentStartIndex;
}
// Check if last n segments are closed.
if (!isClosedShape)
{
int numberOfSegments = segmentStartIndices.Count;
var vertexArray = vertices.Array;
Vector3F v = new Vector3F(segmentEndVertex.X, segmentEndVertex.Y, 0);
for (int i = 0; i < numberOfSegments; i++)
{
int startIndex = segmentStartIndices[i];
if (v == vertexArray[startIndex])
{
// Closed shape found.
isClosedShape = true;
shapeStartIndex = startIndex;
break;
}
}
}
if (isClosedShape)
{
segmentStartIndices.Clear();
}
else
{
segmentStartIndices.Add(segmentStartIndex);
}
CommitVertices(segmentVertices, isNewShape, isClosedShape, vertices);
if (IsStroked(curve))
{
// Apply stroke.
int lineCount = vertexCount / 2;
Stroke(segmentStartIndex, lineCount, isClosedShape, shapeStartIndex, strokeIndices);
}
if (isClosedShape && IsFilled)
{
// Apply fill.
Fill(vertices, shapeStartIndex, fillIndices, ref triangulator);
}
previousVertex.X = segmentEndVertex.X;
previousVertex.Y = segmentEndVertex.Y;
}
ResourcePools <Vector2F> .Lists.Recycle(segmentVertices);
ResourcePools <int> .Lists.Recycle(segmentStartIndices);
if (triangulator != null)
{
triangulator.Recycle();
}
}
