[RESOLVED] Key Press Problem

[mouse88]

I am using the following code to change the direction of my snake in a game:

Public Sub PressKey(ByVal Key As Input.Keys)

        Select Case Key
            Case Keys.Escape 'Exit Game'
                MyBase.Exit()
            Case Keys.Up 'Change Direction To Up'
                If GameState = GameStates.Playing Then
                    If Snake(0).Direction <> BodyParts.Directions.South Then
                        Snake(0).Direction = BodyParts.Directions.North
                    End If
                End If
            Case Keys.Right 'Change Direction To Up'
                If GameState = GameStates.Playing Then
                    If Snake(0).Direction <> BodyParts.Directions.West Then
                        Snake(0).Direction = BodyParts.Directions.East
                    End If
                End If
            Case Keys.Down 'Change Direction To Up'
                If GameState = GameStates.Playing Then
                    If Snake(0).Direction <> BodyParts.Directions.North Then
                        Snake(0).Direction = BodyParts.Directions.South
                    End If
                End If
            Case Keys.Left 'Change Direction To Up
                If GameState = GameStates.Playing Then
                    If Snake(0).Direction <> BodyParts.Directions.East Then
                        Snake(0).Direction = BodyParts.Directions.West
                    End If
                End If
        End Select
End Sub

I have set it up so that if the direction is set as east and the left key is pressed not to change the direction to west so the snake doesn't eat itself.

This works however if the direction is east and I quickly press down then left the snake doesn't have time to move down and just moves to the left causing the snake to eat itself.

Anyone know how i can solve this?

[jmcilhinney]

Add an extra variable to store the direction the snake last moved. You can then compare to that instead of the current direction to determine whether a new direction compatible or not.

[mouse88]

Ok that didn't seem to work. Here's the code:

Public Sub PressKey(ByVal Key As Input.Keys)

        Select Case Key
            Case Keys.Escape 'Exit Game'
                MyBase.Exit()
            Case Keys.Up 'Change Direction To Up'
                If GameState = GameStates.Playing Then
                    If TempDir <> BodyParts.Directions.None And TempDir <> BodyParts.Directions.South Then
                        TempDir = Snake(0).Direction
                        Snake(0).Direction = BodyParts.Directions.North
                    End If
                End If
            Case Keys.Right 'Change Direction To Up'
                If GameState = GameStates.Playing Then
                    TempDir = Snake(0).Direction
                    If TempDir <> BodyParts.Directions.None And TempDir <> BodyParts.Directions.West Then
                        Snake(0).Direction = BodyParts.Directions.East
                    End If
                End If
            Case Keys.Down 'Change Direction To Up'
                If GameState = GameStates.Playing Then
                    TempDir = Snake(0).Direction
                    If TempDir <> BodyParts.Directions.None And TempDir <> BodyParts.Directions.North Then
                        Snake(0).Direction = BodyParts.Directions.South
                    End If
                End If
            Case Keys.Left 'Change Direction To Up
                If GameState = GameStates.Playing Then
                    TempDir = Snake(0).Direction
                    If TempDir <> BodyParts.Directions.None And TempDir <> BodyParts.Directions.East Then
                        Snake(0).Direction = BodyParts.Directions.West
                    End If
                End If
        End Select

    End Sub

Is this what you meant?

[minitech]

If firstsegment.X - nextsegment.X = 1 Then don't move
Same thing with other directions.

[mouse88]

Ok that didn't completely work but did help me solve the problem it is now working. Thanks.