/**This function should generate the mesh that surrounds all of the metaballs.
* Although there may be many metaballs, it will technically only generate a single mesh. **/
void generateMesh()
{
if (metaballs.Count <= 0)
{
return;
}
//STEP 1. Iterate through the cubic region surrounding each metaball.
//Determine the largest size of the region to explore. Need to locate the largest and smallest X, Y and Z values.
vertices.Clear();
triangles.Clear();
float minX, maxX, minY, maxY, minZ, maxZ;
minX = maxX = minY = maxY = minZ = maxZ = 0;
for (int i = 0; i < metaballs.Count; i++)
{
Metaball m = metaballs[i];
Vector3 position = m.transform.position;
float r = m.maxSquaredRadius;
if ((i == 0) || (position.x - r < minX))
{
minX = position.x - r;
}
if ((i == 0) || (position.x + r > maxX))
{
maxX = position.x + r;
}
if ((i == 0) || (position.y - r < minY))
{
minY = position.y - r;
}
if ((i == 0) || (position.y + r > maxY))
{
maxY = position.y + r;
}
if ((i == 0) || (position.z - r < minZ))
{
minZ = position.z - r;
}
if ((i == 0) || (position.z + r > maxZ))
{
maxZ = position.z + r;
}
}
int xResolution = Mathf.CeilToInt((maxX - minX) / cubeLength);
int yResolution = Mathf.CeilToInt((maxY - minY) / cubeLength);
int zResolution = Mathf.CeilToInt((maxZ - minZ) / cubeLength);
Vector3 corner = new Vector3(minX, minY, minZ);
for (int x = 0; x < xResolution; x++)
{
for (int y = 0; y < yResolution; y++)
{
for (int z = 0; z < zResolution; z++)
{
//Start in left, bottom, back corner, slowly work your way to the right, top, front corner.
//For each cube you will examine 8 points, and determine the value at that point
//Each cube is going to need 8 vertices - Order is strange because it needs to fit with the Marching Cubes library
//1. Left Bottom Back
int i = (x * xResolution * xResolution) + (y * yResolution) + z;
float[] cube = new float[8];
cube[0] = getValueAtPoint(new Vector3(corner.x + (cubeLength * x), corner.y + (cubeLength * y), corner.z + (cubeLength * z)));
//2. Left Bottom Front
cube[4] = getValueAtPoint(new Vector3(corner.x + (cubeLength * x), corner.y + (cubeLength * y), corner.z + (cubeLength * (z + 1))));
//3. Left Top Back
cube[3] = getValueAtPoint(new Vector3(corner.x + (cubeLength * x), corner.y + (cubeLength * (y + 1)), corner.z + (cubeLength * z)));
//4. Left Top Front
cube[7] = getValueAtPoint(new Vector3(corner.x + (cubeLength * x), corner.y + (cubeLength * (y + 1)), corner.z + (cubeLength * (z + 1))));
//5. Right Bottom Back
cube[1] = getValueAtPoint(new Vector3(corner.x + (cubeLength * (x + 1)), corner.y + (cubeLength * y), corner.z + (cubeLength * z)));
//6. Right Bottom Front
cube[5] = getValueAtPoint(new Vector3(corner.x + (cubeLength * (x + 1)), corner.y + (cubeLength * y), corner.z + (cubeLength * (z + 1))));
//7. Right Top Back
cube[2] = getValueAtPoint(new Vector3(corner.x + (cubeLength * (x + 1)), corner.y + (cubeLength * (y + 1)), corner.z + (cubeLength * z)));
//8. Right Top Front
cube[6] = getValueAtPoint(new Vector3(corner.x + (cubeLength * (x + 1)), corner.y + (cubeLength * (y + 1)), corner.z + (cubeLength * (z + 1))));
marching.March(corner.x + (cubeLength * x), corner.y + (cubeLength * y), corner.z + (cubeLength * z), cube, cubeLength, vertices, triangles);
}
}
}
mesh.Clear();
mesh.vertices = vertices.ToArray();
mesh.triangles = triangles.ToArray();
mesh.RecalculateNormals();
}
