Implemented basic AI

beamclsh.p8

@@ -10,9 +10,9 @@ function _init()
 		-- 1: action
 		-- 2: score
 		-- 3: over
-	if debounce==nil then
-		debounce=0
-	end
+	if debounce==nil then debounce=0 end
+	if timer==nil then timer=0 end
+
 	cur_state=0
 	init_field()
 	init_player()
@@ -24,7 +24,11 @@ function _update()
 		ply:title_input()
 	elseif cur_state==1 then
 		for p in all(plys) do
+			if p.human then
 				p:input()
+			else
+				p:think()
+			end
 			p:update()
 			p:check()
 		end
@@ -35,6 +39,7 @@ function _update()
 		ply:end_input()
 	end
 	ply:tick_debounce()
+	timer+=1
 end
 
 function _draw()
@@ -136,6 +141,7 @@ function init_player()
 
 	ply={
 		id=1,
+		human=true,
 		scrx=10,
 		scry=1,
 		x=pfield.x1,
@@ -159,6 +165,92 @@ function init_player()
 		end
 	end
 
+	function ply:think()
+		if rndint(100)<5 then
+			self:check_around()
+		else
+			self:check_ahead()
+		end
+	end
+
+	function ply:check_ahead()
+		if self.xspd!=0 then
+			if self:check_x(self.xspd) then self:check_around() end
+		else
+			if self:check_y(self.yspd) then self:check_around() end
+		end
+	end
+
+	function ply:check_x(spd)
+		return sget(self.x+spd,self.y)!=0 or self.x+spd<pfield.x1 or self.x+spd>pfield.x2
+	end
+
+	function ply:check_y(spd)
+		return sget(self.x,self.y+spd)!=0 or self.y+spd<pfield.y1 or self.y+spd>pfield.y2
+	end
+
+	function ply:check_around()
+		-- basically narrow down the list of possible directions and randomly select a random remaining one.
+		local possible_dirs={
+			{spd=-1,axis="y"}, -- north
+			{spd=1,axis="y"},  -- south
+			{spd=1,axis="x"},  -- east
+			{spd=-1,axis="x"}  -- west
+		}
+
+		local available_dirs={}
+
+		for d in all(possible_dirs) do
+			d.spd=self:check_dir(d)
+			if d.spd!=0 then
+				add(available_dirs,d)
+			end
+		end
+
+		local count=0
+
+		for d in all(available_dirs) do
+			count+=1
+		end
+		
+		if count>0 then
+			self:favour_direction(available_dirs, count)
+		end
+	end
+
+	function ply:check_dir(dir)
+		for c=1,2 do
+			local spd=0
+			if dir.spd!=0 then
+				spd=(c*dir.spd)
+			end
+
+			if dir.axis=="x" then
+				if self:check_x(spd) then
+					return 0
+				end				
+			elseif dir.axis=="y" then
+				if self:check_y(spd) then
+					return 0
+				end
+			end
+		end
+		return dir.spd	
+	end
+
+	function ply:favour_direction(dirs, length)
+		dir=dirs[rndint(length)]
+
+		if dir.axis=="x" then
+			self.xspd=dir.spd
+			self.yspd=0
+		else
+			self.xspd=0
+			self.yspd=dir.spd
+		end
+
+	end
+	
 	function ply:score_input()
 		if btn(🅾️) and debounce==0 then
 			next_round()
@@ -169,6 +261,7 @@ function init_player()
 	function ply:title_input()
 		if btn(🅾️) and debounce==0 then
 			cur_state=1
+			srand(timer)
 			debounce=10
 		end
 	end
@@ -231,6 +324,7 @@ function init_player()
 	p2=plys[2]
 	p2.scrx=74
 	p2.id=2
+	p2.human=false
 	p2.x=pfield.x2
 	p2.xspd=-1
 	p2.col=12
@@ -258,7 +352,9 @@ function next_round()
 	pfield:clear()
 	init_field()
 	init_player()
+
 	cur_state=1
+	srand(timer)
 
 	for p in all(plys) do
 		if scores[p.id]>=win_limit then
@@ -319,7 +415,7 @@ function report_winner(id)
 end
 	
 function draw_title()
-	print("beam",64-(4*4),60,11)
+	print("beam",64-(4*4),60,10)
 	print("clash",64-(4*2),70,12)
 
 	print("press 🅾️",64-(4*4),80,7)