void AddCliffEdge(SquareCell cell, GridDirection direction)
{
GridDirection prev = direction.Previous();
GridDirection next = direction.Next();
GridDirection prevN = prev.Previous2();
GridDirection nextN = next.Next2();
SquareCell neighbor = cell.GetNeighbor(direction);
if (neighbor != null)
{
Vector3 c0 = new Vector3(cell.coordinates.X, 0, cell.coordinates.Z) + GridMetrics.GetEdge(prev) + Vector3.up * (int)cell.GridElevations[prev] * GridMetrics.elevationStep;
Vector3 c1 = new Vector3(cell.coordinates.X, 0, cell.coordinates.Z) + GridMetrics.GetEdge(next) + Vector3.up * (int)cell.GridElevations[next] * GridMetrics.elevationStep;
Vector3 n0 = new Vector3(neighbor.coordinates.X, 0, neighbor.coordinates.Z) + GridMetrics.GetEdge(prevN) + Vector3.up * (int)neighbor.GridElevations[prevN] * GridMetrics.elevationStep;
Vector3 n1 = new Vector3(neighbor.coordinates.X, 0, neighbor.coordinates.Z) + GridMetrics.GetEdge(nextN) + Vector3.up * (int)neighbor.GridElevations[nextN] * GridMetrics.elevationStep;
if (c0 != n0 && c1 != n1)
{
if (c0.y > n0.y && n1.y > c1.y) // if edges cross heights along edge X
{
Vector2 cross = CrossingPoint(c1.y - c0.y, n1.y - n0.y, c0.y, n0.y);
Vector3 worldCross = new Vector3(cell.coordinates.X, 0, cell.coordinates.Z)
+ GridMetrics.GetEdge(direction.Previous())
+ (cross.x * 2 * GridMetrics.GetEdge(direction.Next2()))
+ new Vector3(0, cross.y, 0);
terrain.AddTriangle(worldCross, c0, n0);
terrain.AddTriangleColor(Color.cyan);
terrain.AddTriangle(worldCross, n1, c1);
terrain.AddTriangleColor(Color.green);
}
else if (c0.y > n0.y && c1.y > n1.y) // if one edge is always above the other
{
terrain.AddQuad(c0, n0, n1, c1);
terrain.AddQuadColor(retainingWallColor);
}
}
else if (c0.y > n0.y)
{
terrain.AddTriangle(c0, n0, c1);
terrain.AddTriangleColor(retainingWallColor);
}
else if (c1.y > n1.y)
{
terrain.AddTriangle(c0, n1, c1);
terrain.AddTriangleColor(retainingWallColor);
}
}
}