public static void GenerateChunkInterior(List <Vector3> vertices, List <int> triangles, sbyte[][][][] data, int res)
{
for (int x = 2; x < res - 2; x++)
{
for (int y = 2; y < res - 2; y++)
{
for (int z = 2; z < res - 2; z++)
{
Util.GridCell cell = new Util.GridCell();
cell.points = new Util.Point[8];
for (int i = 0; i < 8; i++)
{
Vector3Int offset = new Vector3Int((int)Tables.CellOffsets[i].x, (int)Tables.CellOffsets[i].y, (int)Tables.CellOffsets[i].z) + new Vector3Int(x, y, z);
sbyte density = data[(int)offset.x][offset.y][offset.z][0];
cell.points[i].density = density;
cell.points[i].position = offset;
}
GenerateRegularCell(cell, vertices, triangles, 0);
}
}
}
}
public static void GenerateRegularCell(Util.GridCell cell, List <Vector3> vertices, List <int> triangles, float isovalue)
{
Vector3[] vertlist = new Vector3[12];
int i, ntriang;
int cubeindex;
cubeindex = 0;
if (cell.points[0].density < isovalue)
{
cubeindex |= 1;
}
if (cell.points[1].density < isovalue)
{
cubeindex |= 2;
}
if (cell.points[2].density < isovalue)
{
cubeindex |= 4;
}
if (cell.points[3].density < isovalue)
{
cubeindex |= 8;
}
if (cell.points[4].density < isovalue)
{
cubeindex |= 16;
}
if (cell.points[5].density < isovalue)
{
cubeindex |= 32;
}
if (cell.points[6].density < isovalue)
{
cubeindex |= 64;
}
if (cell.points[7].density < isovalue)
{
cubeindex |= 128;
}
/* Cube is entirely in/out of the surface */
if (Tables.edgeTable[cubeindex] == 0)
{
return;
}
/* Find the vertices where the surface intersects the cube */
if ((Tables.edgeTable[cubeindex] & 1) == 1)
{
vertlist[0] = UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[1]);
}
if ((Tables.edgeTable[cubeindex] & 2) == 2)
{
vertlist[1] = UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[2]);
}
if ((Tables.edgeTable[cubeindex] & 4) == 4)
{
vertlist[2] = UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[3]);
}
if ((Tables.edgeTable[cubeindex] & 8) == 8)
{
vertlist[3] = UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]);
}
if ((Tables.edgeTable[cubeindex] & 16) == 16)
{
vertlist[4] = UtilFuncs.Lerp(isovalue, cell.points[4], cell.points[5]);
}
if ((Tables.edgeTable[cubeindex] & 32) == 32)
{
vertlist[5] = UtilFuncs.Lerp(isovalue, cell.points[5], cell.points[6]);
}
if ((Tables.edgeTable[cubeindex] & 64) == 64)
{
vertlist[6] = UtilFuncs.Lerp(isovalue, cell.points[6], cell.points[7]);
}
if ((Tables.edgeTable[cubeindex] & 128) == 128)
{
vertlist[7] = UtilFuncs.Lerp(isovalue, cell.points[7], cell.points[4]);
}
if ((Tables.edgeTable[cubeindex] & 256) == 256)
{
vertlist[8] = UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[4]);
}
if ((Tables.edgeTable[cubeindex] & 512) == 512)
{
vertlist[9] = UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[5]);
}
if ((Tables.edgeTable[cubeindex] & 1024) == 1024)
{
vertlist[10] = UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[6]);
}
if ((Tables.edgeTable[cubeindex] & 2048) == 2048)
{
vertlist[11] = UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[7]);
}
/* Create the triangle */
ntriang = 0;
for (i = 0; Tables.triTable[cubeindex][i] != -1; i += 3)
{
ntriang++;
}
for (i = 0; Tables.triTable[cubeindex][i] != -1; i++)
{
triangles.Add(vertices.Count);
vertices.Add(vertlist[Tables.triTable[cubeindex][i]]);
}
}
public static void GenerateChunkExterior(List <Vector3> vertices, List <int> triangles, sbyte[][][][] data, byte chunkLod, int res)
{
int rm2 = res - 2;
int rm4 = res - 4;
for (int x = 0; x < res; x += 2)
{
for (int y = 0; y < res; y += 2)
{
for (int z = 0; z < res; z += 2)
{
bool isMinimal = x == 0 || y == 0 || z == 0;
bool isMaximal = x == rm2 || y == rm2 || z == rm2;
if (!isMinimal && !isMaximal)
{
continue;
}
byte cellLod = 0;
if (x == 0)
{
cellLod |= 1;
}
if (x == rm2)
{
cellLod |= 2;
}
if (y == 0)
{
cellLod |= 4;
}
if (y == rm2)
{
cellLod |= 8;
}
if (z == 0)
{
cellLod |= 16;
}
if (z == rm2)
{
cellLod |= 32;
}
cellLod = (byte)(cellLod & chunkLod);
byte cellLod2 = 0;
if (x == 2)
{
cellLod2 |= 1;
}
if (x == rm4)
{
cellLod2 |= 2;
}
if (y == 2)
{
cellLod2 |= 4;
}
if (y == rm4)
{
cellLod2 |= 8;
}
if (z == 2)
{
cellLod2 |= 16;
}
if (z == rm4)
{
cellLod2 |= 32;
}
cellLod2 = (byte)(cellLod2 & chunkLod);
int iPos = -1;
int numOnes = 0;
for (int i = 0; i < 6; i++)
{
if (((cellLod >> i) & 1) == 1)
{
numOnes++;
iPos = i;
}
}
if (numOnes == 1)
{
GenerateTransitionCell(new Vector3Int(x, y, z), vertices, triangles, cellLod2, data, tvCellRotations[iPos]);
}
else
{
Util.GridCell cell = new Util.GridCell();
cell.points = new Util.Point[8];
for (int i = 0; i < 8; i++)
{
Vector3Int offset = (new Vector3Int((int)Tables.CellOffsets[i].x, (int)Tables.CellOffsets[i].y, (int)Tables.CellOffsets[i].z)) * 2 + new Vector3Int(x, y, z);
sbyte density = data[(int)offset.x][offset.y][offset.z][0];
cell.points[i].density = density;
cell.points[i].position = offset;
}
GenerateRegularCell(cell, vertices, triangles, 0);
}
}
}
}
}
public static void PolyganiseTetrahedron(Util.GridCell cell, List <Vector3> vertices, float isovalue)
{
int triangleIndex = 0;
if (cell.points[0].density < isovalue)
{
triangleIndex |= 1;
}
if (cell.points[1].density < isovalue)
{
triangleIndex |= 2;
}
if (cell.points[2].density < isovalue)
{
triangleIndex |= 4;
}
if (cell.points[3].density < isovalue)
{
triangleIndex |= 8;
}
// these cases were taken from https://github.com/Calvin-L/MarchingTetrahedrons/blob/master/Decimate.cpp
switch (triangleIndex)
{
case 0:
case 15:
break;
case 0x01:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[1]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[2]));
break;
case 0x02:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
break;
case 0x04:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[1]));
break;
case 0x08:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[1]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]));
break;
case 0x03:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[1]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
break;
case 0x05:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[3]));
break;
case 0x09:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[1]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[2]));
break;
case 0x06:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[1]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[2]));
break;
case 0x0C:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[1]));
break;
case 0x0A:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]));
break;
case 0x07:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[3], cell.points[1]));
break;
case 0x0B:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[1]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[2], cell.points[0]));
break;
case 0x0D:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[0]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[3]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[1], cell.points[2]));
break;
case 0x0E:
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[1]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[2]));
vertices.Add(UtilFuncs.Lerp(isovalue, cell.points[0], cell.points[3]));
break;
}
}
