Function move_sand()
	For s.sand = Each sand
		If ReadPixel(s\x,s\y+1) = -16777216 Then
			s\y = s\y + 1
		EndIf		
	Next
End Function

Graphics 320,240
SetBuffer BackBuffer()
Dim mat(319,239)

Function update()
	For x=0 To 319
		For y=239 To 0 Step -1
			If(mat(x,y)=1)
				If(y<239)
					If(mat(x,y+1)=0)
					mat(x,y)=0
					mat(x,y+1)=1
					ElseIf(mat(x,y+1)=1)
						If(x>0 And y<239 And mat(x-1,y)=0 And mat(x-1,y+1)=0)
							mat(x,y)=0
							mat(x-1,y+1)=1
						ElseIf(x<319 And y<239 And mat(x+1,y)=0 And mat(x+1,y+1)=0)
							mat(x,y)=0
							mat(x+1,y+1)=1
						EndIf
					EndIf
				EndIf
			EndIf
		Next
	Next
End Function

Function draw()
	For x=0 To 319
		For y=0 To 239
			If(mat(x,y)=1) Color 255,255,255:Rect(x,y,1,1)
		Next
	Next
End Function


Repeat
	Cls
	mat(160,0)=1
	update()
	draw()
	Flip
Until KeyDown(1)