private bool TryPropagateDown(Vector3 pos, LiquidVoxel voxel)
{
Vector3 checkPos = pos + Vector3.down;
LiquidVoxel lowerVoxel = GetVoxelAt(checkPos);
//Can't propagate to solid
if (lowerVoxel.IsSolid)
{
return(false);
}
if (lowerVoxel.IsAir)
{
//Just move this voxel down one
SetWriteVoxel(checkPos, voxel);
return(true);
}
//TODO: Add support for combining VoxelLiquids
int capacity = LiquidVoxel.MAX_VOLUME - lowerVoxel.Volume;
if (capacity > 0)
{
byte amount = (byte)Mathf.Min(capacity, voxel.Volume);
SetWriteVoxel(checkPos, lowerVoxel.AddVolume(amount));
if (voxel.Volume > amount)
{
SetWriteVoxel(pos, voxel.LessVolume(amount));
}
return(true);
}
return(false);
}
private void AddOrUpdateVoxel(Vector3 pos, LiquidVoxel voxel)
{
if (writeVoxels.TryGetValue(pos, out LiquidVoxel other))
{
writeVoxels[pos] = other.AddVolume(voxel.Volume);
}
else
{
writeVoxels.Add(pos, voxel);
}
}
private void SetWriteVoxel(Vector3 pos, LiquidVoxel voxel)
{
if (writeVoxels.ContainsKey(pos))
{
writeVoxels[pos] = voxel;
}
else
{
writeVoxels.Add(pos, voxel);
}
}
private void Propagate()
{
bool changed = false;
if (Random.Range(0f, 1f) > .5f)
{
waterVoxels.Add(new Vector3(Random.Range(0, 10), 8, Random.Range(0, 10)), new LiquidVoxel(1, 7));
changed = true;
}
writeVoxels.Clear();
foreach (var tuple in waterVoxels)
{
Vector3 pos = tuple.Key;
LiquidVoxel voxel = tuple.Value;
if (TryPropagateDown(pos, voxel))
{
changed = true;
continue;
}
else if (TryPropagateOut(pos, voxel))
{
changed = true;
continue;
}
else
{
AddOrUpdateVoxel(pos, voxel);
}
}
Dictionary <Vector3, LiquidVoxel> temp = waterVoxels;
waterVoxels = writeVoxels;
writeVoxels = temp;
if (changed)
{
Remesh();
}
}
private bool TryPropagateOut(Vector3 pos, LiquidVoxel voxel)
{
//Can only propagate if there is more than 1 unit of volume
if (voxel.Volume <= 1)
{
return(false);
}
Vector3[] surroundingPositions = new Vector3[]
{
pos - Vector3.right, //left
pos + Vector3.right, //right
pos + Vector3.forward, //front
pos - Vector3.forward //rear
};
bool[] updated = new bool[] { false, false, false, false };
LiquidVoxel[] surroundingVoxels = new LiquidVoxel[4];
for (int i = 0; i < 4; i++)
{
surroundingVoxels[i] = GetVoxelAt(surroundingPositions[i]);
}
//First try to propagate to air spaces
int numAirSpaces = 0;
foreach (LiquidVoxel vox in surroundingVoxels)
{
if (vox.IsAir)
{
numAirSpaces++;
}
}
//distribute to nearby cells
int minimumVolume = 7;
for (int i = 0; i < 4; i++)
{
if (surroundingVoxels[i].Volume < minimumVolume)
{
minimumVolume = surroundingVoxels[i].Volume;
}
}
bool propagated = false;
int currentVolume = voxel.Volume;
while (currentVolume > minimumVolume)
{
//distribute to minimum volume voxels
for (int i = 0; i < 4; i++)
{
if ((currentVolume - 1) <= minimumVolume || currentVolume == 1)
{
break;
}
//Can't propagate to a solid
if (surroundingVoxels[i].IsSolid)
{
continue;
}
if (surroundingVoxels[i].Volume == minimumVolume)
{
if (surroundingVoxels[i].IsAir)
{
surroundingVoxels[i] = new LiquidVoxel(voxel.Id, 1);
}
else
{
surroundingVoxels[i] = surroundingVoxels[i].AddVolume(1);
}
updated[i] = true;
currentVolume--;
propagated = true;
}
}
minimumVolume++;
}
if (propagated)
{
for (int i = 0; i < 4; i++)
{
if (surroundingVoxels[i].IsSolid)
{
continue;
}
if (surroundingVoxels[i].Volume > 0 && updated[i])
{
SetWriteVoxel(surroundingPositions[i], surroundingVoxels[i]);
}
}
SetWriteVoxel(pos, voxel.WithVolume(currentVolume));
}
return(propagated);
}
