3D Point rotation

[Vindicator209]

Sorry... This is more of a math question, really.

I made a simple little 3d box that you can move around in, I intend on being able to create objects and stuff in it, but I put that off because I don't know how to do point rotations.

I want to transform/rotate a set of points, given the center and the rotation angle.

I did some googling, and I came up with lots of "3D Rotation Matrix" stuff but with a geometry-level education, I'm not understanding it.

Can anyone give me a tip?

Heres my code, incase you want to know what it's for.

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#include <GUIConstantsEx.au3>
#include <StaticConstants.au3>
#include <WindowsConstants.au3>
#include <Array.au3>
#include <Misc.au3>
Global $w = 1000
Global $h = 800
Global $d = 800
Global $x_center = Round($w/2,0)
Global $y_center = Round($h/2,0)
$dll = DllOpen("User32.dll")
$Form1 = GUICreate("Form1", $w+100, $h + 100, -1, -1)
$Stats_1 = GUICtrlCreateLabel("",0,100,200,200)
GUICtrlSetBkColor(-1, $GUI_BKCOLOR_TRANSPARENT)
GUISetState(@SW_SHOW)
Dim $ava[1][3]
$ava[0][0] = 0
$ava[0][1] = 0
$ava[0][2] = 0
$f_skip = 2 ;frame skip
$fc= 0
#cs
;Draw Grid
For $z_x = 0 to $w
    For $z_y = 2 to 800
        For $z_z = 0 to 150
            drawPoint($z_x,$z_y,$z_z)
            $z_z += 50
        Next
        $z_y += 50
    Next
    $z_x += 50
Next
#ce
;Draw Cube
drawPoint(0,0,0)
drawPoint($w,0,0)
drawPoint($w,$h,0)
drawPoint(0,$h,0)
drawPoint(0,0,$d)
drawPoint($w,0,$d)
drawPoint($w,$h,$d)
drawPoint(0,$h,$d)
$x_vel = 0
$y_vel = 0
$z_vel = 0
$lastpoint = drawPoint(0,0,0)
$posChange = False
While 1
    calcInput()
    calcPhys()
    $nMsg = GUIGetMsg()
    $Stats = "X: " & Round( $ava[0][0] , 2)
    $Stats &= @CRLF & "Y: " & Round( $ava[0][1] , 2)
    $Stats &= @CRLF & "Z: " & Round( $ava[0][2] , 2)
    $Stats &= @CRLF & "Xvel: " & Round( $x_vel , 2)
    $Stats &= @CRLF & "Yvel: " & Round( $y_vel , 2)
    $Stats &= @CRLF & "Zvel: " & Round( $z_vel , 2)
    GUICtrlSetData($Stats_1,$Stats)
    Switch $nMsg
        Case $GUI_EVENT_CLOSE
            Exit

    EndSwitch
WEnd

GUISetState(@SW_SHOW)
Func drawObject($obj)
    For $i = 0 to UBound($obj) - 1
        $obj[$i][0] = drawPoint($obj[$i][1],$obj[$i][2],$obj[$i][3])
    Next
    Return $obj
EndFunc
Func drawPoint($x,$y,$z)
    $y = ($h-$y)
    $x_dist = ($x_center - $x) / 10
    $y_dist = ($y_center - $y) / 10
    $point = GUICtrlCreateLabel("+", $x + ($x_dist * ($z/100)), $y + ($y_dist * ($z/100)), 50, 50,$SS_CENTER)
    $size = 50 - ((32 / $d) * $z)
    If $size < 1 Then $size = 1
    GUICtrlSetFont(-1, $size)
    $color = Round( ($z / $d) * 99, 0 )
    If $color > 99 then $color = 99
    If $color < 0 Then $color = 0
    GUICtrlSetColor(-1, "0x00" & $color & "00")
    GUICtrlSetBkColor(-1, $GUI_BKCOLOR_TRANSPARENT)
    Return $point
EndFunc
Func calcPhys()
    $ava[0][0] += $x_vel
    $ava[0][1] += $y_vel
    $ava[0][2] += $z_vel
    If $x_vel > 1 Then
        $x_vel -= 0.5
    ElseIf $x_vel < -1 Then
        $x_vel += 0.5
    Else
        $x_vel = 0
    EndIf

    If $z_vel > 1 Then
        $z_vel -= 0.5
    ElseIf $z_vel < -1 Then
        $z_vel += 0.5
    Else
        $z_vel = 0
    EndIf
    If $ava[0][0] < 0 Then
        $ava[0][0] = 0
        $x_vel *= -2/3
    ElseIf $ava[0][0] > $w Then
        $ava[0][0] = $w
        $x_vel *= -2/3
    EndIf
    If $ava[0][1] < 0 Then
        $ava[0][1] = 0
        If Abs($y_vel) < 1 Then
        $y_vel = 0
        Else
        $y_vel *= -2/3
        EndIf
    ElseIf $ava[0][1] > $h Then
        $ava[0][1] = $h
        $y_vel *= -1
    EndIf
    If $ava[0][2] < 0 Then
        $ava[0][2] = 0
        $z_vel *= -2/3
    ElseIf $ava[0][2] > $d Then
        $ava[0][2] = $d
        $z_vel *= -2/3
    EndIf
    If $fc = $f_skip Then
    GUICtrlDelete($lastpoint)
    $lastpoint = drawPoint($ava[0][0],$ava[0][1],$ava[0][2])
    $fc = 0
    Else
    $fc +=1
    EndIf
$y_vel -= 2
EndFunc
Func calcInput()
    If _IsPressed(25,$dll) Then
        $x_vel -= 2
    EndIf
    If _IsPressed(27,$dll) Then
        $x_vel += 2
    EndIf
    If _IsPressed(26,$dll) Then
        $z_vel += 2
    EndIf
    If _IsPressed(28,$dll) Then
        $z_vel -= 2
    EndIf
    If _IsPressed(20,$dll) Then
        $y_vel += 6
    EndIf
EndFunc

[Yashied]

Perhaps it will be useful to you.

http://www.autoitscript.com/forum/index.php?showtopic=107180

[UEZ]

Or have a look to #09 Rotating Cube in Some Graphical Examples Using GDI+!

UEZ

[jchd]

Sorry... This is more of a math question, really.

No problem so far.

I want to transform/rotate a set of points, given the center and the rotation angle.

I did some googling, and I came up with lots of "3D Rotation Matrix" stuff but with a geometry-level education, I'm not understanding it.

In short, you need to know that rotations in 3-D space are not commutative. Then, there are two main common approaches to computing 3-D rotations: the [messy] so-called Euler angles and the _much_ simpler quaternions. You'll have to do you own searches for all these terms, concepts and possible implementations. Honestly, it isn't very difficult and if you have a ounce of motivation, you'll do it.

Euler angles: here (gimbal lock included, free of charge)

Quaternions used for computing rotations: here

I'd like to have more time to help you on this, but I'm currently too busy for doing so. Sorry for that.