Files
wave/wfc/generator.gd

67 lines
2.4 KiB
GDScript

extends Node
## The generator works with pure numbers, you'll need something else to convert it to actual tiles
## Makes a new chunk, derived from the given WFC samples
func generate_chunk_at(_x: int, _y: int, _chunk_array: Array[Chunk], _samples: Array[PackedInt32Array]) -> Chunk:
#TODO: fix the chunk-edges
var chunk: Chunk = Chunk.new(_x, _y)
while _set_lowest_entropy_tile(chunk, _samples) > 0: pass
_chunk_array.append(chunk)
return chunk
## Returns the entropy of the selected tile
func _set_lowest_entropy_tile(chunk: Chunk, _samples: Array[PackedInt32Array]) -> int:
var entropy: Array[Array] = []
entropy.resize(Chunk.CHUNK_WIDTH * Chunk.CHUNK_HEIGHT)
#iterate over unset tiles with valid neighbours
for x in range(Chunk.CHUNK_WIDTH):
for y in range((Chunk.CHUNK_HEIGHT)):
if chunk.data[y * Chunk.CHUNK_HEIGHT + x] == 0: #direct access, to skip extra checks
entropy[y * Chunk.CHUNK_HEIGHT + x] = _find_valid_samples(chunk, x, y, _samples)
#find the lowest-entropy tile
var lowest: int = -1
for i in range(Chunk.CHUNK_WIDTH * Chunk.CHUNK_HEIGHT):
if entropy[i].size() == 0: continue #no options
if lowest < 0:
lowest = i
continue
if entropy[i].size() < entropy[lowest].size():
lowest = i
#finished
if lowest < 0: return lowest
#finally, set the tile from the sample
var s: PackedInt32Array = entropy[lowest].pick_random()
chunk.data[lowest] = s[4]
return entropy.size()
## Returns the valid samples
func _find_valid_samples(chunk: Chunk, tile_x: int, tile_y: int, _samples: Array[PackedInt32Array]) -> Array[PackedInt32Array]:
var valid: Array[PackedInt32Array] = []
#use a lambda for easy reading below
var compare := func (tile_value: int, sample: int) -> bool:
return tile_value <= 0 or tile_value == sample
#filter the samples
for sample in _samples:
if !compare.call(chunk.get_tile(tile_x -1, tile_y -1), sample[0]): continue
if !compare.call(chunk.get_tile(tile_x , tile_y -1), sample[1]): continue
if !compare.call(chunk.get_tile(tile_x +1, tile_y -1), sample[2]): continue
if !compare.call(chunk.get_tile(tile_x -1, tile_y ), sample[3]): continue
# //
if !compare.call(chunk.get_tile(tile_x +1, tile_y ), sample[5]): continue
if !compare.call(chunk.get_tile(tile_x -1, tile_y +1), sample[6]): continue
if !compare.call(chunk.get_tile(tile_x , tile_y +1), sample[7]): continue
if !compare.call(chunk.get_tile(tile_x +1, tile_y +1), sample[8]): continue
valid.append(sample)
return valid