tarn_fov_demo.lua

-- We only need the config module
tarn_loadmodule("config")

-- Configure the display window
tarn_display_width = 40
tarn_display_height = 25
tarn_display_title = "Tarn"
tarn_init()

-- Globally accessible variables
player = {}
map, map_width, map_height, fov = {}, 20, 10, nil

-- Set up player stuff
player = {
	glyph = "@",
	color = color.white,
	x = 10,
	y = 5,
	move = function(self, rx, ry)
		local tx, ty = self.x + rx, self.y + ry
		self.x, self.y = tx, ty
	end,
	draw = function(self)
		sprite = string.format("$%d%s$0", self.color, self.glyph)
		tarn_print(self.x, self.y, sprite)
	end
}

-- Generate an empty map (1-based index)
for y = 1, map_height do
	for x = 1, map_width do
		local tile
		if math.random(3) == math.random(3) then
			tile = { glyph = '#', color = color.grey }
		else
			tile = { glyph = '.', color = color.green }
		end
		map[y*map_width+x] = tile
	end
end

-- Generate the FOV overlay (0-based index)
fov = tarn_fov_new(map_width, map_height)
for y = 0,map_height-1 do
	for x = 0,map_width-1 do
		if map[(y+1)*map_width+(x+1)].glyph == "#" then
			tarn_fov_set(fov, x, y, false, false)
		else
			tarn_fov_set(fov, x, y, true, true)
		end
	end
end
tarn_fov_do(fov, player.x-1, player.y-1, 3)

-- Main game loop
while true do
	tarn_clear()
	tarn_fov_do(fov, player.x-1, player.y-1, 3)
	for y = 1, map_height do
		for x = 1, map_width do
			if tarn_fov_has(fov, x-1, y-1) then
				tile = string.format("$%d%s$0", map[y*map_width+x].color, map[y*map_width+x].glyph)
			else
				tile = string.format("$%d%s$0", color.darkgrey, map[y*map_width+x].glyph)
			end
			tarn_print(x, y, tile)
		end
	end
	player:draw()
	tarn_draw()
			
	key = tarn_getkey()
	key.c_str = string.format("%c", key.c)
	if key.c_str == "Q" then
		break
	elseif key.vk == vk.up then
		player:move(0, -1)
	elseif key.vk == vk.down then
		player:move(0, 1)
	elseif key.vk == vk.left then
		player:move(-1, 0)
	elseif key.vk == vk.right then
		player:move(1, 0)
	end
end