2d collision

Anyone have a RPG stile collision routine to share? Better yet how about one for sliding collision. I have started on one below:

Function PlayerToWallCollision(p.tPlayer)
;Find four corners of Player and check
;them For collision with the walls.
;
;Also steer around corners automaticly
; +---+
; | P |
; +---+
	Local TL=0,BL=0,TR=0,BR=0
	If Walls((p\Sprite\X)/TileSize,(p\Sprite\OldY)/TileSize)=1 Then TL=1
	If Walls((p\Sprite\OldX)/TileSize,(p\Sprite\Y)/TileSize)=1 Then TL=1

	If Walls((p\Sprite\X+p\Sprite\Width)/TileSize,(p\Sprite\OldY)/TileSize)=1 Then TR=1
	If Walls((p\Sprite\OldX+p\Sprite\Width)/TileSize,(p\Sprite\Y)/TileSize)=1 Then TR=1

	If Walls((p\Sprite\X)/TileSize,(p\Sprite\OldY+p\Sprite\Height)/TileSize)=1 Then BL=1
	If Walls((p\Sprite\OldX)/TileSize,(p\Sprite\Y+p\Sprite\Height)/TileSize)=1 Then BL=1

	If Walls((p\Sprite\X+p\Sprite\Width)/TileSize,(p\Sprite\OldY+p\Sprite\Height)/TileSize)=1 Then BR=1
	If Walls((p\Sprite\OldX+p\Sprite\Width)/TileSize,(p\Sprite\Y+p\Sprite\Height)/TileSize)=1 Then BR=1
	If 1=1 Then;p\Jump= False Then
	If TL+BL+TR+BR > 0 Then
		Select p\Sprite\WalkDir
			Case UPDIR
				If TL+TR < 2 Then
					If TL > 0 Then 
						If BR <> 1 Then p\Sprite\X=p\Sprite\OldX+p\Speed:p\Sprite\Y=p\Sprite\OldY
					End If
					If TR > 0 Then 
						If BL <> 1 Then p\Sprite\X=p\Sprite\OldX-p\Speed:p\Sprite\Y=p\Sprite\OldY
					End If
				Else
					p\Sprite\Y=p\Sprite\OldY
				End If
			Case DOWNDIR
				If BL+BR < 2 Then
					If BL > 0 Then 
						If TR <> 1 Then p\Sprite\X=p\Sprite\OldX+p\Speed:p\Sprite\Y=p\Sprite\OldY
					End If
					If BR > 0 Then 
						If TL <> 1 Then p\Sprite\X=p\Sprite\OldX-p\Speed:p\Sprite\Y=p\Sprite\OldY
					End If
				Else
					p\Sprite\Y=p\Sprite\OldY
				End If
			Case LEFTDIR
				If BL+TL < 2 Then
					If BL > 0 Then 
						If BR <> 1 Then p\Sprite\Y=p\Sprite\OldY-p\Speed:p\Sprite\X=p\Sprite\OldX
					End If
					If TL > 0 Then 
						If BL <> 1 And BR <> 1 Then p\Sprite\Y=p\Sprite\OldY+p\Speed:p\Sprite\X=p\Sprite\OldX
					End If
				Else
					p\Sprite\X=p\Sprite\OldX
				End If
			Case RIGHTDIR
				If BR+TR < 2 Then
					If BR > 0 Then 
						If TL <> 1 Then p\Sprite\Y=p\Sprite\OldY-p\Speed:p\Sprite\X=p\Sprite\OldX
					End If
					If TR > 0 Then 
						If BL <> 1 Then p\Sprite\Y=p\Sprite\OldY+p\Speed:p\Sprite\X=p\Sprite\OldX
					End If
				Else
					p\Sprite\X=p\Sprite\OldX
				End If
		End Select
		If TL+BL+TR+BR >=3 Then p\Sprite\X=p\Sprite\OldX:p\Sprite\Y=p\Sprite\OldY
	End If
	EndIf
End Function