screenwidth=800:screenheight=800
Graphics screenwidth,screenheight,32,2
SetBuffer BackBuffer()
SeedRnd MilliSecs()

Global spaceextent=4

Dim space(spaceextent*2+1,spaceextent*2+1)
Dim newspace(spaceextent*2+1,spaceextent*2+1)
Dim pill(spaceextent*2+1,spaceextent*2+1)
Dim newpill(spaceextent*2+1,spaceextent*2+1)

Global dx=0,dy=1
Global sight#=2,sanity#=1

Function move()
	For x=0 To spaceextent*2
	If x+dx>=0 And x+dx<=spaceextent*2
		For y=0 To spaceextent*2
		If y+dy>=0 And y+dy<=spaceextent*2
			newspace(x,y)=space(x+dx,y+dy)
			newpill(x,y)=pill(x+dx,y+dy)
		EndIf
		Next
	EndIf
	Next
	
	If dx=0
		For off=0 To spaceextent-sight-1;Floor(sight)-1
			y=spaceextent*(1+dy)-off*dy
			For x=0 To spaceextent*2
				newspace(x,y)=Rand(0,1)
				If newspace(x,y)=0 Then newpill(x,y)=Rand(0,1) Else newpill(x,y)=0
			Next
		Next
	Else
		For off=0 To spaceextent-sight-1;Floor(sight)-1
			x=spaceextent*(1+dx)-off*dx
			For y=0 To spaceextent*2
				newspace(x,y)=Rand(0,1)
				If newspace(x,y)=0 Then newpill(x,y)=Rand(0,1) Else newpill(x,y)=0
			Next
		Next
	EndIf
	
	For x=0 To spaceextent*2
	For y=0 To spaceextent*2
		space(x,y)=newspace(x,y)
		pill(x,y)=newpill(x,y)
	Next
	Next
	
	If pill(spaceextent,spaceextent)=1
		pill(spaceextent,spaceextent)=0
		If sanity=1
			sight=sight+Rnd(0.1,0.2)
			If sight>spaceextent Then sight=spaceextent
		Else
			sanity=sanity+0.2
			If sanity>1 Then sanity=1
		EndIf
	EndIf
End Function

For x=0 To spaceextent*2
For y=0 To spaceextent*2
	space(x,y)=Rand(0,1)
Next
Next
space(spaceextent,spaceextent)=0
space(spaceextent,spaceextent-1)=0

wobble#=0
tick=0
time#=0
oldms=MilliSecs()
While Not KeyDown(1)
	wobble=wobble+.005
	
	If KeyDown(200)
		If space(spaceextent,spaceextent-1)=0
			If dx<>0 Or dy<>-1 Then tick=0
			dx=0
			dy=-1
		EndIf
	ElseIf KeyDown(208)
		If space(spaceextent,spaceextent+1)=0
			If dx<>0 Or dy<>1 Then tick=0
			dx=0
			dy=1
		EndIf
	ElseIf KeyDown(203)
		If space(spaceextent-1,spaceextent)=0
			If dx<>-1 Or dy<>0 Then tick=0
			dx=-1
			dy=0
		EndIf
	ElseIf KeyDown(205)
		If space(spaceextent+1,spaceextent)=0
			If dx<>1 Or dy<>0 Then tick=0
			dx=1
			dy=0
		EndIf
	EndIf
	If KeyHit(57)
		dx=0
		dy=0
		tick=0
	EndIf

	For x=0 To spaceextent*2
	For y=0 To spaceextent*2
		xdist=Abs(x-spaceextent)
		ydist=Abs(y-spaceextent)
		If xdist>ydist Then dist=xdist Else dist=ydist
		If dist>Floor(sight)+1
			light#=0
		ElseIf dist>Floor(sight)
			light#=sight-Floor(sight)
		Else
			light#=1
		EndIf
		cx=(x-spaceextent)*50+screenwidth/2-tick*dx
		cy=(y-spaceextent)*50+screenheight/2-tick*dy
		If space(x,y):
			If light>0
				Color 255*light,0,0
				Rect cx-25,cy-25,50,50
				Color 0,255*light,0
				o1=((wobble*25+x*19+y*13) Mod 3)-1
				o2=((wobble*27+x*17+y*11) Mod 3)-1
				If x>0 And space(x-1,y)=0 Then Line cx-25-o1,cy-25,cx-25-o2,cy+25
				If x<spaceextent*2 And space(x+1,y)=0 Then Line cx+25+o1,cy-25,cx+25+o2,cy+25
				If y>0 And space(x,y-1)=0 Then Line cx-25,cy-25,cx+25,cy-25
				If y<spaceextent*2 And space(x,y+1)=0 Then Line cx-25,cy+25,cx+25,cy+25
				;Color 255,255,255
				;Rect (x-spaceextent)*50+screenwidth/2-tick*dx,(y-spaceextent)*50+screenheight/2-tick*dy,50,50,0
			EndIf
		EndIf
		If pill(x,y)
			If light>0
				Color 0,0,255*light
				Oval (x-spaceextent)*50+screenwidth/2-tick*dx-10,(y-spaceextent)*50+screenheight/2-tick*dy-10,20,20
			EndIf
		EndIf
	Next
	Next
	
	Text 0,0,dx
	Text 0,12,dy
	
	Color 255*sanity,255*sanity,0
	Oval screenwidth/2-15,screenheight/2-15,30,30,0
	
	sight=sight-0.005
	If sight<0 
		sight=0
		sanity=sanity-0.01
		If sanity<=0
			wobble#=Rnd(360)
			fade#=0
			For c=1 To 255
				ClsColor 255-c,255-c,255-c
				Cls
				Flip
			Next
			FlushKeys()
			While Not GetKey()
				Cls
				fade=fade+.005
				If fade>1 Then fade=1
				wobble=wobble+Rnd(.2)
				Color (Sin(wobble)*.5+.5)*255*fade,(Sin(wobble*4)*.5+.5)*255*fade,(Sin(wobble*.6+70)*.5+.5)*255*fade
				Text screenwidth/2,screenheight/2,"You kept your sanity for "+Str(time)+" seconds",1,1
				Flip
			Wend
			End
		EndIf
	EndIf
	ms=MilliSecs()
	t#=(ms-oldms)/1000.0
	oldms=ms
	tsense#=1.0/sight
	If tsense>10 Then tsense#=10
	time=time+t*tsense
	Text 0,0,time
	If dx<>0 Or dy<>0
		If space(spaceextent+dx,spaceextent+dy)=0
			tick=tick+5
		EndIf
		If tick=50
			move()
			tick=0
		EndIf
	EndIf
	Flip
	Cls
Wend