VB - Face target given its x and y

[erix920]

I've seen a few people asking if there's any source code to face a target. I think there's some sources out there but all are built around other libraries. The code I wrote just needs you to edit a few things (3 lines) so that it knows your player's x,y and rotation. I'm using this code in my upcoming bot and it's used for auto attack and it works so well I couldn't keep my hard work all bottled up.

I hope someone can find a use for it.

#Region " Change Angle "

    ''' <summary>
    ''' Finds what quadrant of the unit circle the given coordinates are in and returns the proper angle in radians
    ''' </summary>
    ''' <param name="x"></param>
    ''' <param name="y"></param>
    ''' <returns></returns>
    ''' <remarks></remarks>
    Private Shared Function Find_Quadrant(ByVal x As Single, ByVal y As Single)
        If x > 0 And y > 0 Then
            Return 1.5 * Math.PI
        ElseIf x < 0 And y > 0 Then
            Return 0
        ElseIf x < 0 And y < 0 Then
            Return Math.PI / 2
        Else
            Return Math.PI
        End If
    End Function

    ''' <summary>
    ''' !!!!!!!!!!!!!!DO NOT EDIT THIS!!!!!!!!!!!!!!
    ''' This function changes the player's facing value by holding down the turnleft or turnright key until the player is facing the target. 
    ''' </summary>
    ''' <param name="object_x">Object's X Coordinate</param>
    ''' <param name="object_y">Object's Y Coordinate</param>
    ''' <remarks></remarks>
    Private Sub Change_Angle(ByRef inst As InstanceStruct, ByVal object_x As Single, ByVal object_y As Single)
        Dim player_x As Single = inst.p_BRObjectManager.Me.X
        Dim player_y As Single = inst.p_BRObjectManager.Me.Y
        Dim x3, y3 As Single
        Dim differenceX As Single = object_x - player_x
        Dim differenceY As Single = object_y - player_y
        Dim quadrant, sec, quadint As Single
        Dim kb_delay As Integer
        Dim kb_speed As Integer
        Dim player_Facing As Single = inst.p_BRObjectManager.Me.Facing

        SystemParametersInfo(SPI_GETKEYBOARDDELAY, 0, kb_delay, 0)
        SystemParametersInfo(SPI_GETKEYBOARDSPEED, 0, kb_speed, 0)

        If differenceX > 0 And differenceY > 0 Then
            quadrant = 1.5 * Math.PI
            sec = Math.PI
            quadint = 1
            x3 = object_x
            y3 = player_y
        ElseIf differenceX < 0 And differenceY > 0 Then
            quadrant = 0
            quadint = 2
            sec = Math.PI / 2
            x3 = player_x
            y3 = object_y
        ElseIf differenceX < 0 And differenceY < 0 Then
            quadrant = Math.PI / 2
            sec = Math.PI
            quadint = 3
            x3 = object_x
            y3 = player_y
        Else
            quadrant = Math.PI
            sec = Math.PI / 1.5
            quadint = 4
            x3 = player_x
            y3 = object_y
        End If

        Dim dPlayer2Target As Single = Math.Sqrt(differenceX ^ 2 + differenceY ^ 2)
        Dim dThird2Target As Single = Math.Sqrt((object_x - x3) ^ 2 + (object_y - y3) ^ 2)

        Dim quad_ang As Single = Find_Quadrant(object_x - player_x, object_y - player_y)
        Dim total_ang As Single = Math.Abs(Math.Asin(dThird2Target / dPlayer2Target))

        If quadint = 2 Then
            sec = (quadrant + total_ang) - (player_Facing - (Math.PI / 2)) - 0.15
            If player_Facing > 0 And player_Facing <= Math.PI / 2 Then
                If sec > Math.PI Then ' This will give us the smallest turning angle
                    sec = 2 * Math.PI - sec
                    sec = sec / -1
                    sec = sec
                End If
            ElseIf player_Facing > Math.PI / 2 And player_Facing <= Math.PI Then
                sec = sec + 0.3
            ElseIf player_Facing > Math.PI And player_Facing <= Math.PI * 1.5 Then
                sec = sec + 0.3
            ElseIf player_Facing > Math.PI * 1.5 And player_Facing <= Math.PI * 2 Then
                If Math.Abs(sec) > Math.PI Then ' This will give us the smallest turning angle  -- or atleast I hope
                    sec = 2 * Math.PI - Math.Abs(sec)
                    'sec = sec / -1
                    'sec = sec
                End If
            End If
        ElseIf quadint = 3 Then
            If player_Facing > 0 And player_Facing <= Math.PI / 2 Then
                sec = (quadrant + total_ang) - (player_Facing - (Math.PI / 2)) - 0.15
            ElseIf player_Facing > Math.PI And player_Facing <= Math.PI * 1.5 Then
                sec = (quadrant + total_ang) - (player_Facing - Math.PI / 2)
                If sec > 0 Then
                    sec = sec - 0.15
                Else
                    sec = sec + 0.15
                End If
            ElseIf player_Facing > Math.PI * 1.5 And player_Facing <= Math.PI * 2 Then
                sec = (quadrant + total_ang) - (player_Facing - Math.PI / 2) + 0.15
            Else
                sec = (quadrant + total_ang) - (player_Facing - (Math.PI / 2)) - 0.15
            End If
        ElseIf quadint = 4 Then
            If player_Facing > 0 And player_Facing <= Math.PI / 2 Then
                sec = (quadrant + total_ang) - (player_Facing - Math.PI / 2) - 0.15
            ElseIf player_Facing > Math.PI * 1.5 And player_Facing <= Math.PI * 2 Then
                sec = (quadrant + total_ang) - (player_Facing - Math.PI / 2) + 0.15
            Else
                sec = (quadrant + total_ang) - (player_Facing - (Math.PI / 2)) - 0.15
            End If
        ElseIf quadint = 1 Then
            sec = (quadrant + total_ang) - (player_Facing - (Math.PI / 2)) - 0.15
            If player_Facing > 0 And player_Facing <= Math.PI / 2 Then
                If sec > Math.PI Then ' This will give us the smallest turning angle
                    sec = 2 * Math.PI - sec
                    sec = sec / -1
                    sec = sec
                End If
                If sec > 0 Then
                    sec = sec - 0.15
                Else
                    sec = sec + 0.15
                End If
            ElseIf player_Facing > Math.PI / 2 And player_Facing <= Math.PI Then
                If sec > Math.PI Then ' This will give us the smallest turning angle
                    sec = 2 * Math.PI - sec
                    sec = sec / -1
                    sec = sec + 0.3
                End If
            ElseIf player_Facing > Math.PI And player_Facing <= Math.PI * 1.5 Then
                If sec > Math.PI Then ' This will give us the smallest turning angle
                    sec = 2 * Math.PI - sec
                    sec = sec / -1
                    sec = sec + 0.3
                End If
            End If
        End If
        Dim changeAngle As Single = player_Facing - ((sec) - total_ang + quadrant)

        If sec > 0 Then
            'MsgBox("Move left: " & sec)
            Dim lastAngle, firstAngle, additive As Single
            Do Until Math.Abs(sec) < additive
                firstAngle = inst.p_BRObjectManager.Me.Facing

                For Each key As Integer In thisInst.p_WowBindings.KEY_TurnLeft
                    SendMessage(inst.p_WowProcess.MainWindowHandle, WM_KEYDOWN, key, 0)
                Next

                Threading.Thread.Sleep(kb_delay + kb_speed)
                lastAngle = inst.p_BRObjectManager.Me.Facing
                If lastAngle < firstAngle Then
                    lastAngle += 2 * Math.PI
                End If
                additive += (lastAngle - firstAngle)

                If halt = True Then
                    Exit Do
                End If
            Loop

            For Each key As Integer In thisInst.p_WowBindings.KEY_TurnLeft
                SendMessage(inst.p_WowProcess.MainWindowHandle, WM_KEYUP, key, 0)
            Next
        Else
            'MsgBox("Move right: " & sec)
            Dim lastAngle, firstAngle, additive As Single
            Do Until Math.Abs(sec) < additive
                firstAngle = inst.p_BRObjectManager.Me.Facing

                For Each key As Integer In thisInst.p_WowBindings.KEY_TurnRight
                    SendMessage(inst.p_WowProcess.MainWindowHandle, WM_KEYDOWN, key, 0)
                Next

                Threading.Thread.Sleep(kb_delay + kb_speed)
                lastAngle = inst.p_BRObjectManager.Me.Facing
                If lastAngle > firstAngle Then
                    lastAngle += 2 * Math.PI
                End If
                additive += (firstAngle - lastAngle)

                If halt = True Then
                    Exit Do
                End If
            Loop

            For Each key As Integer In thisInst.p_WowBindings.KEY_TurnRight
                SendMessage(inst.p_WowProcess.MainWindowHandle, WM_KEYUP, key, 0)
            Next

        End If
        inst.next_Object.angleChanged = True
    End Sub
#End Region

[MaiN]

float facingRequired = (float)Math.Atan2(targetY - myY, targetX - myX);

There is no need to figure out the quadrants etc. yourself. Most libraries have atan2 built in.

[erix920]

Now I have to see if the values are the same. I'll let you know how mad I am after.

[streppel]

they are for sure,atan2 has the quadrant handling in by default. you can check msdn for reference on what the returnvalues of the function represent
on some games you have to adjust this the return value a little(like making it go from 0 to 2pi or from 0 to 1 etc) but i guess in wow it works straight away

[erix920]

Didn't know there was a function that did the same thing as my 4 lines did.

[EmilyStrange]

Atan2 is just a replacement for the find_quadrant function though correct?

Trigonometry Education FTW

http://www.amazon.com/Fundamentals-M.../dp/0131687425

http://www.amazon.com/Beginning-Math.../dp/0735713901

http://www.amazon.com/exec/obidos/ASIN/0123742978

[erix920]

Thank you for the wildly pointless post.

I'm pretty sure writing out a function that does the job shows more understanding than using math.atan2.

Edit: Those amazon books are too expensive anyway

[Azzie2k8]

I'm pretty sure writing out a function that does the job shows more understanding than using math.atan2.

I'm not sure about that...

[EmilyStrange]

I'm pretty sure writing out a function that does the job shows more understanding than using math.atan2.

Yes and no.

In the same way that the mental exercise of writing your own compilers and interpreters is useful for understanding, but doing so due to ignorance of other solutions, especially of such an obvious piece of functionality, is just willful. You clearly demonstrate this willfulness in the re-invention of Atan2 and the claim that knowledge is expensive, hence you will be doomed to repeat this cycle in the future.

[erix920]

Your post are always so detailed EmilyStrange.

Regardless of my apparent ignorance of using frameworked functions, I still donate this code to anyone who doesn't want to spend the time figuring it out.

Maybe they can reimplement using math.atan2 to clean things up.

[Cypher]

Yes and no.

In the same way that the mental exercise of writing your own compilers and interpreters is useful for understanding, but doing so due to ignorance of other solutions, especially of such an obvious piece of functionality, is just willful. You clearly demonstrate this willfulness in the re-invention of Atan2 and the claim that knowledge is expensive, hence you will be doomed to repeat this cycle in the future.

Perfect explanation. I'm always entertained whenever I point out that someone has reinvented a standard library function in their code (and done it in an inferior fashion usually) and they reply by saying it makes them "less noob" or some crap like that. Great for learning, not so much for actually writing production code.

@erix920: I'm not saying that's what you did in this particular case. It's just what happens more often than not.

[EmilyStrange]

Perfect explanation. I'm always entertained whenever I point out that someone has reinvented a standard library function in their code (and done it in an inferior fashion usually) and they reply by saying it makes them "less noob" or some crap like that. Great for learning, not so much for actually writing production code.

@erix920: I'm not saying that's what you did in this particular case. It's just what happens more often than not.

Who are you and what have you done with Cypher's body?

[Cypher]

Who are you and what have you done with Cypher's body?

I think someone put benzodiazepines in my breakfast.

[123jokesonme]

I think someone put benzodiazepines in my breakfast.

haha i think "someone" forced me to take these to xanax bars to! =]

[erix920]

I agree with you all, using library code is better than expanding it and making it less efficient (or the same as). In my case it probably makes it confusing.

Anyway if anyone has any questions about the missing API just ask.