protected void DoSkyLight(ChunkData chunk, int x, int ystart, int z)
{
var tileX = chunk.X * 16 + x;
var tileZ = chunk.Y * 16 + z;
var height = chunk.GetHeight(x, z);
// From where should we start calculating
int newHeight = Math.Max(height, ystart);
// We need to cast light through transparent blocks
while (newHeight > 0 && Block.LightAbsorbs[chunk.GetBlock(x, newHeight - 1, z)] == 0)
newHeight--;
// Nothing changed, we don't need to calculate
if (newHeight == height)
return;
chunk.SetHeight(x, z, newHeight);
/* The new height is lower than the last, that means all the tiles
* above are fully lit */
if (newHeight < height) {
for (int y = newHeight; y < height; y++) {
chunk.SkyLight.SetValue(x, y, z, 15);
}
} else if (newHeight > height) {
ScheduleUpdate(LightType.Sky, new Box(tileX, height, tileZ, tileX, newHeight, tileZ));
for (int y = height; y < newHeight; y++) {
chunk.SkyLight.SetValue(x, y, z, 0);
}
}
}
