Lighting

Block lighting

Skylights

Skylights are calculated from height-maps and are stored separately from the block lights. They are calculated by the world's height-map that is generated by the chunk generator since it is the only one that knows the real height of the world, since it's infinite on the y-axis and it's impossible to calculate otherwise. Height-maps are stored in the chunk pillars, sets that are identified by the X and Z coordinate and have unlimited chunks on the y-axis.

Calculation

On player move (chunk change):

Server-side (transmission)

• When a server-side player changes chunk the new chunks entering it's view distance are sent to the client.
• If the chunk has not been generated, generates first the height-map of its chunk pillar and secondly the blocks of the chunk. Finally diffuses skylights.
• If the player hasn't received the height-map of the chunk pillar yet, sends it.
• Now we can send the blocks.

Client-side (reception)

• Client-side, when height-map is received, we simply store it in the relative chunk pillar. We create it if doesn't exist (based on the X and Z stored in the packet).
• When the chunk is received, we can diffuse the skylight based on the height-map of the chunk pillar container of the chunk received.