public bool Equals(VoxelCorners <T> other)
{
return(EqualityComparer <T> .Default.Equals(Corner1, other.Corner1) &&
EqualityComparer <T> .Default.Equals(Corner2, other.Corner2) &&
EqualityComparer <T> .Default.Equals(Corner3, other.Corner3) &&
EqualityComparer <T> .Default.Equals(Corner4, other.Corner4));
}
private static VoxelCorners <float> GetVoxelDensities(int2 position, NativeArray <float> densities, int chunkSize)
{
VoxelCorners <float> voxelDensities = new VoxelCorners <float>();
for (int i = 0; i < 4; i++)
{
int2 cornerPosition = position + SquareCorners[i];
int index = cornerPosition.y * (chunkSize + 1) + cornerPosition.x;
voxelDensities[i] = densities[index];
}
return(voxelDensities);
}
public static int CalculateSquareIndex(VoxelCorners <float> densities, float isolevel)
{
int cubeIndex = 0;
if (densities.Corner1 <= isolevel)
{
cubeIndex |= 1;
}
if (densities.Corner2 <= isolevel)
{
cubeIndex |= 2;
}
if (densities.Corner3 <= isolevel)
{
cubeIndex |= 4;
}
if (densities.Corner4 <= isolevel)
{
cubeIndex |= 8;
}
return(cubeIndex);
}
public static Mesh CreateMesh(NativeArray <float> densities, int chunkSize, float isolevel)
{
List <Vector3> vertices = new List <Vector3>();
for (int x = 0; x < chunkSize; x++)
{
for (int y = 0; y < chunkSize; y++)
{
int2 position = new int2(x, y);
VoxelCorners <float> voxelDensities = GetVoxelDensities(position, densities, chunkSize);
int squareIndex = CalculateSquareIndex(voxelDensities, isolevel);
if (squareIndex == 0)
{
continue; // This voxel is completely outside the surface
}
float2 bottomLeft = position + SquareCorners[0];
float2 bottomRight = position + SquareCorners[1];
float2 topRight = position + SquareCorners[2];
float2 topLeft = position + SquareCorners[3];
float2 leftEdge = VertexInterpolate(bottomLeft, topLeft, voxelDensities.Corner1, voxelDensities.Corner4, isolevel);
float2 topEdge = VertexInterpolate(topLeft, topRight, voxelDensities.Corner4, voxelDensities.Corner3, isolevel);
float2 rightEdge = VertexInterpolate(bottomRight, topRight, voxelDensities.Corner2, voxelDensities.Corner3, isolevel);
float2 bottomEdge = VertexInterpolate(bottomLeft, bottomRight, voxelDensities.Corner1, voxelDensities.Corner2, isolevel);
if (squareIndex == 1)
{
CreateTriangle(bottomLeft, leftEdge, bottomEdge, vertices);
}
else if (squareIndex == 2)
{
CreateTriangle(bottomEdge, rightEdge, bottomRight, vertices);
}
else if (squareIndex == 3)
{
CreateTriangle(leftEdge, bottomRight, bottomLeft, vertices);
CreateTriangle(leftEdge, rightEdge, bottomRight, vertices);
}
else if (squareIndex == 4)
{
CreateTriangle(topEdge, topRight, rightEdge, vertices);
}
else if (squareIndex == 5)
{
float average = (voxelDensities.Corner1 + voxelDensities.Corner2 + voxelDensities.Corner3 + voxelDensities.Corner4) / 4f;
if (average < isolevel)
{
CreateTriangle(bottomLeft, leftEdge, bottomEdge, vertices);
CreateTriangle(leftEdge, rightEdge, bottomEdge, vertices);
CreateTriangle(leftEdge, topEdge, rightEdge, vertices);
CreateTriangle(topEdge, topRight, rightEdge, vertices);
}
else
{
CreateTriangle(bottomLeft, leftEdge, bottomEdge, vertices);
CreateTriangle(topEdge, topRight, rightEdge, vertices);
}
}
else if (squareIndex == 6)
{
CreateTriangle(topEdge, topRight, bottomRight, vertices);
CreateTriangle(topEdge, bottomRight, bottomEdge, vertices);
}
else if (squareIndex == 7)
{
CreateTriangle(leftEdge, bottomRight, bottomLeft, vertices);
CreateTriangle(leftEdge, topEdge, bottomRight, vertices);
CreateTriangle(topEdge, topRight, bottomRight, vertices);
}
else if (squareIndex == 8)
{
CreateTriangle(topLeft, topEdge, leftEdge, vertices);
}
else if (squareIndex == 9)
{
CreateTriangle(topLeft, topEdge, bottomEdge, vertices);
CreateTriangle(topLeft, bottomEdge, bottomLeft, vertices);
}
else if (squareIndex == 10)
{
float average = (voxelDensities.Corner1 + voxelDensities.Corner2 + voxelDensities.Corner3 + voxelDensities.Corner4) / 4f;
if (average < isolevel)
{
CreateTriangle(topLeft, topEdge, leftEdge, vertices);
CreateTriangle(leftEdge, topEdge, rightEdge, vertices);
CreateTriangle(leftEdge, rightEdge, bottomEdge, vertices);
CreateTriangle(bottomEdge, rightEdge, bottomRight, vertices);
}
else
{
CreateTriangle(bottomEdge, rightEdge, bottomRight, vertices);
CreateTriangle(topLeft, topEdge, leftEdge, vertices);
}
}
else if (squareIndex == 11)
{
CreateTriangle(topLeft, topEdge, bottomLeft, vertices);
CreateTriangle(bottomLeft, topEdge, rightEdge, vertices);
CreateTriangle(bottomLeft, rightEdge, bottomRight, vertices);
}
else if (squareIndex == 12)
{
CreateTriangle(topLeft, topRight, leftEdge, vertices);
CreateTriangle(leftEdge, topRight, rightEdge, vertices);
}
else if (squareIndex == 13)
{
CreateTriangle(bottomLeft, topLeft, bottomEdge, vertices);
CreateTriangle(topLeft, rightEdge, bottomEdge, vertices);
CreateTriangle(topLeft, topRight, rightEdge, vertices);
}
else if (squareIndex == 14)
{
CreateTriangle(topLeft, topRight, leftEdge, vertices);
CreateTriangle(leftEdge, topRight, bottomEdge, vertices);
CreateTriangle(bottomEdge, topRight, bottomRight, vertices);
}
else if (squareIndex == 15)
{
CreateTriangle(bottomLeft, topLeft, bottomRight, vertices);
CreateTriangle(topLeft, topRight, bottomRight, vertices);
}
}
}
Mesh mesh = new Mesh();
int[] triangles = CreateTriangles(vertices.Count);
mesh.SetVertices(vertices);
mesh.SetTriangles(triangles, 0);
return(mesh);
}
