private Tuple <HermiteData, Edge[]> CubeInfo(Chunk c, Vector3I min, GridPoint XYZ, GridPoint XMaxYZ, GridPoint XYMaxZ, GridPoint XYZMax, GridPoint XMaxYMaxZ, GridPoint XMaxYZMax, GridPoint XYMaxZMax, GridPoint XMaxYMaxZMax) { HermiteData hermiteData = new HermiteData(new List <Vector3>(), new List <Vector3>()); // get edge table index int cubeIndex = 0; if (XYZ.Density < _minimumSolidDensity) { cubeIndex += 1; } if (XMaxYZ.Density < _minimumSolidDensity) { cubeIndex += 2; } if (XMaxYMaxZ.Density < _minimumSolidDensity) { cubeIndex += 4; } if (XYMaxZ.Density < _minimumSolidDensity) { cubeIndex += 8; } if (XYZMax.Density < _minimumSolidDensity) { cubeIndex += 16; } if (XMaxYZMax.Density < _minimumSolidDensity) { cubeIndex += 32; } if (XMaxYMaxZMax.Density < _minimumSolidDensity) { cubeIndex += 64; } if (XYMaxZMax.Density < _minimumSolidDensity) { cubeIndex += 128; } GridPoint[][][] lookupTable = new GridPoint[][][] { new GridPoint[][] { new GridPoint[] { XYZ, XYZMax, }, new GridPoint[] { XYMaxZ, XYMaxZMax, } }, new GridPoint[][] { new GridPoint[] { XMaxYZ, XMaxYZMax, }, new GridPoint[] { XMaxYMaxZ, XMaxYMaxZMax, } }, }; int edge = _edgeTable[cubeIndex]; List <Edge> xEdges = new List <Edge>(); // loop through all the edges for (int i = 0; i < 12; i++) { // if this edge contains no intersection, skip it if ((edge & (1 << i)) == 0) { continue; } int[] corner1Offset = _intersections[i][0]; int[] corner2Offset = _intersections[i][1]; Vector3I corner1 = min; Vector3I corner2 = min; corner1.X += corner1Offset[0]; corner1.Y += corner1Offset[1]; corner1.Z += corner1Offset[2]; corner2.X += corner2Offset[0]; corner2.Y += corner2Offset[1]; corner2.Z += corner2Offset[2]; GridPoint corner1Point = lookupTable[corner1Offset[0]][corner1Offset[1]][corner1Offset[2]]; GridPoint corner2Point = lookupTable[corner2Offset[0]][corner2Offset[1]][corner2Offset[2]]; Vector3I delta = (corner2 - corner1) * (corner1Point.Density < _minimumSolidDensity ? -1 : 1); // negate if corner1 is less than the isovalue because we assume corner2 at first. Direction dir = GetDirectionFromDelta(delta); xEdges.Add(new Edge(corner1, corner2, dir)); Vector3 intersectionPoint = DualContouring.InterpolateIntersectionPoint(_minimumSolidDensity, corner1.ToVector3(), corner2.ToVector3(), corner1Point.Density, corner2Point.Density); Vector3I minCorner = Vector3I.Min(corner1, corner2); GridPoint minPoint = (minCorner == corner1) ? corner1Point : corner2Point; Vector3 naturalNormal = _densityGradientFunction.df(intersectionPoint.X, intersectionPoint.Y, intersectionPoint.Z); Vector3F8 compressedNaturalNormal = new Vector3F8(naturalNormal); Vector3 normal = compressedNaturalNormal.ToVector3(); //normal = naturalNormal; switch (dir) { case Direction.XIncreasing: case Direction.XDecreasing: normal = minPoint.XPositiveNormal; if (normal == Vector3.Zero) { GridPoint withNormal = new GridPoint(minPoint); withNormal.XPositiveNormal = naturalNormal; c.SetPoint(minCorner.X, minCorner.Y, minCorner.Z, withNormal, true); } break; case Direction.YIncreasing: case Direction.YDecreasing: normal = minPoint.YPositiveNormal; if (normal == Vector3.Zero) { GridPoint withNormal = new GridPoint(minPoint); withNormal.YPositiveNormal = naturalNormal; c.SetPoint(minCorner.X, minCorner.Y, minCorner.Z, withNormal, true); } break; case Direction.ZIncreasing: case Direction.ZDecreasing: normal = minPoint.ZPositiveNormal; if (normal == Vector3.Zero) { GridPoint withNormal = new GridPoint(minPoint); withNormal.ZPositiveNormal = naturalNormal; c.SetPoint(minCorner.X, minCorner.Y, minCorner.Z, withNormal, true); } break; } if (normal == Vector3.Zero) { normal = naturalNormal; } normal.Normalize(); hermiteData.Add(intersectionPoint, normal); } Tuple <HermiteData, Edge[]> ret = new Tuple <HermiteData, Edge[]>(hermiteData, xEdges.ToArray()); return(ret); }