This might be more like what you're looking for, unlike water that seeks the lowest path, this sand can be piled up in spots.
Open in online IDESeedRnd MilliSecs() SetBuffer BackBuffer() Type sand Field x% Field y% Field colors% Field kind End Type Graphics3D 1024, 768, 32, 2 Cls LockBuffer BackBuffer() Global black = ReadPixel (0, 0) UnlockBuffer BackBuffer() Repeat Line 0, 100, 200, 300 Line 200, 300, 400, 100 ;Line 100,200,400,200 If MouseDown(1) Then s.sand = New sand s\x = MouseX() s\y = MouseY() s\kind = 1 s\colors = Rnd(0, 100000) End If If frame Mod 2 Then LockBuffer BackBuffer() For s.sand = Each sand WritePixelFast s\x, s\y, s\colors If ReadPixelFast (s\x, s\y+1) = black Then s\y = s\y + 1 EndIf If ReadPixelFast (s\x+1, s\y) = black And ReadPixelFast (s\x+1, s\y+1)=black Then s\x = s\x+1:s\y = s\y + 1 EndIf If ReadPixelFast (s\x-1, s\y) = black And ReadPixelFast (s\x-1, s\y+1)=black Then s\x = s\x-1:s\y = s\y + 1 EndIf If s\y > GraphicsHeight()-1 Then Delete s Next UnlockBuffer BackBuffer() Flip False Cls End If frame=frame +1 If frame > 1 Then frame=0 For s.sand = Each sand n=n+1 Next Text 0, 0, n n=0 Until KeyHit(1) End