public override Vector4 getEdgeData(Point3 cube, int edgeId)
{
var signs = a.GetEdgeSigns(cube, edgeId);
if (signs[0] != signs[1])
{
return(a.getEdgeData(cube, edgeId));
}
signs = b.GetEdgeSigns(cube - _offset, edgeId);
if (signs[0] != signs[1])
{
return(b.getEdgeData(cube - _offset, edgeId));
}
throw new InvalidOperationException("No crossing edge here!");
}
private static void buildTriangleIndices(List <int> indices, AbstractHermiteGrid grid, Dictionary <Point3, int> vIndex, List <DCVoxelMaterial> triangleMaterials)
{
// Possible quads
var offsets = new[] { Point3.UnitX(), Point3.UnitY(), Point3.UnitZ(), };
var rights = new[] { Point3.UnitY(), Point3.UnitZ(), Point3.UnitX(), };
var ups = new[] { Point3.UnitZ(), Point3.UnitX(), Point3.UnitY(), };
var unitEdges = offsets.Select(o => grid.GetEdgeId(new Point3(), o)).ToArray();
//TODO: should be unit test
for (int i = 0; i < 3; i++)
{
Debug.Assert(grid.GetEdgeOffsets(unitEdges[i])[0] == new Point3());
Debug.Assert(grid.GetEdgeOffsets(unitEdges[i])[1] == offsets[i]);
}
grid.ForEachCube(o =>
{
if (!vIndex.ContainsKey(o))
{
return; // No sign changes so no relevant edges here
}
for (int i = 0; i < 3; i++)
{
var edgeId = unitEdges[i];
if (!grid.HasEdgeData(o, edgeId))
{
continue;
}
// Generate quad
var right = rights[i];
var up = ups[i];
DCVoxelMaterial mat;
var signs = grid.GetEdgeSigns(o, edgeId);
// Face towards air by swapping right and up
if (signs[1])
{
var swap = right;
right = up;
up = swap;
mat = grid.GetMaterial(o + offsets[i]);
}
else
{
mat = grid.GetMaterial(o);
}
// build quad faces
var a = o - right;
var b = o - up;
var ab = o - right - up;
if (!new[] { a, b, ab }.All(vIndex.ContainsKey))
{
continue; // This should never happen unless on the side of the field, maybe add a check for this?
}
indices.AddRange(new[] { vIndex[o], vIndex[a], vIndex[ab] });
indices.AddRange(new[] { vIndex[o], vIndex[ab], vIndex[b] });
triangleMaterials.Add(mat);
triangleMaterials.Add(mat);
}
});
}
