add shooting of bolts

src/data/controls.lua

@@ -9,4 +9,6 @@ return {
 	aim_down = "down",
 	aim_left = "left",
 	aim_right = "right",
+
+	shoot = "space"
 }

src/lib/nata.lua

@@ -362,6 +362,27 @@ function Pool:remove(f)
 	end
 end
 
+function Pool:removeEntity(e)
+	checkArgument(1, e, 'table')
+	for groupName, group in pairs(self.groups) do
+		for i = #group.entities, 1, -1 do
+			if group.entities[i] == e then
+				self:emit('removeFromGroup', groupName, e)
+				table.remove(group.entities, i)
+				group.hasEntity[e] = nil
+			end
+		end
+	end
+	for i = #self.entities, 1, -1 do
+		if self.entities[i] == e then
+			self:emit('remove', e)
+			table.remove(self.entities, i)
+			self.hasEntity[e] = nil
+			break
+		end
+	end
+end
+
 --- Registers a function to be called when an event is emitted.
 -- @string event the event to listen for
 -- @tparam function f the function to call

src/main.lua

@@ -2,6 +2,7 @@ local Gamestate = require("lib.hump.gamestate")
 
 function love.load()
 	love.math.setRandomSeed(love.timer.getTime())
+	love.keyboard.setKeyRepeat(true)
 	math.randomseed(love.timer.getTime())
 
 	Gamestate.switch(require("states.main"))

src/states/main.lua

@@ -2,18 +2,24 @@ local MainState = {}
 local pprint = require("lib.pprint")
 local nata   = require("lib.nata")
 local Vec    = require("lib.brinevector")
+local data   = require("data")
 
 function MainState:enter()
 	self.ecs = nata.new{
 		groups = {
 			physical = {filter = {"pos", "vel"}},
-			player = {filter = {"pos", "acc", "speed", "score"}},
-			sprite = {filter = {"sprite"}}
+			player = {filter = {
+				"pos", "acc", "speed",
+				"bolt_count",
+				"bolt_cooldown", "bolt_speed", "bolt_friction"
+			}},
+			sprite = {filter = {"sprite"}},
+			bolt = {filter={"pos", "vel", "bolt"}}
 		},
 		systems = {
 			require("systems.physics"),
 			require("systems.player"),
-			require("systems.sprite"),
+			require("systems.sprite")
 		},
 		data = {}
 	}
@@ -22,9 +28,14 @@ function MainState:enter()
 		pos = Vec(100, 100),
 		vel = Vec(0, 0),
 		acc = Vec(),
-		score = 0,
+
 		sprite = {},
-		speed = 100
+		friction = 0.998,
+		speed = 800,
+		bolt_count = 1,
+		bolt_speed = 1000,
+		bolt_cooldown = 0.2,
+		bolt_friction = 0.9
 	}
 end
 
@@ -41,6 +52,10 @@ function MainState:mousemoved(...)
 	self.ecs:emit("mousemoved", ...)
 end
 
+function MainState:keypressed(...)
+	self.ecs:emit("keypressed", ...)
+end
+
 function MainState:draw()
 	self.ecs:emit("draw")
 end

src/systems/physics.lua

@@ -5,6 +5,9 @@ function Physics:update(dt)
 		if e.acc then
 			e.vel = e.vel + e.acc * dt
 		end
+		if e.friction then
+			e.vel = e.vel * (1 - math.min(e.friction, 1)) ^ dt
+		end
 
 		e.pos = e.pos + e.vel * dt
 	end

src/systems/player.lua

@@ -35,6 +35,12 @@ function Player:getAimDirection(player)
 	end
 end
 
+function Player:addToGroup(group, e)
+	if group == "player" then
+		e.bolt_cooldown_timer = e.bolt_cooldown_timer or 0
+	end
+end
+
 function Player:update(dt)
 	local move_direction = self:getMoveDirection()
 
@@ -42,9 +48,42 @@ function Player:update(dt)
 		self.use_mouse_aim = false
 	end
 
+	-- Update each player
 	for _, e in ipairs(self.pool.groups.player.entities) do
+		-- Update where they are aiming/looking
 		e.aim_dir = self:getAimDirection(e)
+		-- Update acceleration to make the player move
 		e.acc = move_direction * e.speed
+
+		-- Check if the player tried to shoot a bolt
+		if love.keyboard.isDown(controls.shoot) and
+			(e.aim_dir.x ~= 0 or e.aim_dir.y ~= 0) and
+			e.bolt_cooldown_timer == 0 and
+			e.bolt_count > 0
+		  then
+			e.bolt_cooldown_timer = e.bolt_cooldown
+			e.bolt_count = e.bolt_count - 1
+			self.pool:queue{
+				pos = e.pos + e.aim_dir * 30,
+				vel = e.aim_dir * e.bolt_speed,
+				friction = e.bolt_friction,
+				bolt = true,
+				sprite = {}
+			}
+		end
+
+		-- Decrease bolt cooldown timer
+		if e.bolt_cooldown_timer > 0 then
+			e.bolt_cooldown_timer = math.max(0, e.bolt_cooldown_timer - dt)
+		end
+
+		-- If the player is nearby a non-moving bolt, pick it up
+		for _, bolt in ipairs(self.pool.groups.bolt.entities) do
+			if (e.pos-bolt.pos).length < 30 and bolt.vel.length < 1 then
+				self.pool:removeEntity(bolt)
+				e.bolt_count = e.bolt_count + 1
+			end
+		end
 	end
 end