kingdoms_game/mods/utils/blockutil.lua

--[[
Copyright (c) 2014, Robert 'Bobby' Zenz
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OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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--- Various functions related to blocks/chunks.
blockutil = {
	--- The size of one block in nodes.
	BLOCK_SIZE = 16,
	
	--- The size of a mapchunk in blocks.
	MAPCHUNK_IN_BLOCKS_SIZE = 5,
	
	--- The size of one mapchunk in nodes.
	MAPCHUNK_SIZE = 80,
	
	--- The size of one node.
	NODE_SIZE = 1
}


--- Gets the begin coordinates of the block the given coordinates are in.
--
-- @param x The x coordinate. Can also be a table with the x, y and z values.
-- @param y The y coordinate.
-- @param z The z coordinate.
-- @return The coordinates (x, y, z) of the blocks begin.
function blockutil.get_begin(x, y, z)
	if type(x) == "table" then
		local pos = x
		
		x = pos.x
		y = pos.y
		z = pos.z
	end
	
	if y == nil and z == nil then
		local begin = x
		
		if begin >= 48 then
			local difference = math.fmod(begin + 32, 80)
			begin = begin - difference
		elseif begin >= -32 then
			return -32
		else
			local difference = math.fmod(math.abs(begin + 32), 80)
			
			if difference > 0 then
				difference = 80 - difference
			end
			
			begin = begin - difference
		end
		
		return begin
	end
	
	return blockutil.get_begin(x), blockutil.get_begin(y), blockutil.get_begin(z)
end

--- Gets the begin coordinates of the block the given coordinates are in
-- as position (a table with three entries, x, y, and z).
--
-- @param x The x coordinate. Can also be a table with the x, y and z values.
-- @param y The y coordinate.
-- @param z The z coordinate.
-- @return The coordinates (x, y, z) of the blocks begin as pos.
function blockutil.get_begin_pos(x, y, z)
	local begin_x, begin_y, begin_z = blockutil.get_begin(x, y, z)
	
	return {
		x = begin_x,
		y = begin_y,
		z = begin_z
	}
end

--- Gets the end coordinates of the block the given coordinates are in.
--
-- @param x The x coordinate. Can also be a table with the x, y and z values.
-- @param y The y coordinate.
-- @param z The z coordinate.
-- @return The coordinates (x, y, z) of the blocks end.
function blockutil.get_end(x, y, z)
	if type(x) == "table" then
		local pos = x
		
		x = pos.x
		y = pos.y
		z = pos.z
	end
	
	if y == nil and z == nil then
		return blockutil.get_begin(x + constants.block_size) - 1
	end
	
	return blockutil.get_end(x), blockutil.get_end(y), blockutil.get_end(z)
end

--- Gets the end coordinates of the block the given coordinates are in
-- as position (a table with three entries, x, y, z).
--
-- @param x The x coordinate. Can also be a table with the x, y and z values.
-- @param y The y coordinate.
-- @param z The z coordinate.
-- @return The coordinates (x, y, z) of the blocks end as pos.
function blockutil.get_end_pos(x, y, z)
	local end_x, end_y, end_z = blockutil.get_end(x, y, z)
	
	return {
		x = end_x,
		y = end_y,
		z = end_z
	}
end