XProfan

Windowtitle "ArcTan2, ArcTan4 and Icon Texturen"
windowstyle 1+4+8+16
window (%maxx * 0.5 - 200), (%maxy * 0.5 - 150)  - 400,300'kompatible spelling
Declare tex&, hPic&, zrot!, oglX&, oglY&
oGL("init",%hWnd,1,1,1,0)
oGL("posmode",1)
'Texture from Icons
Mcls 32,32
startpaint -1
DrawIcon "GESICHT", 0,0
endpaint
hPic&=create("HPIC",0,"&MEMBMP")
tex&=ogl("getTextureBmp",hPic&,1)
DeleteObject hPic&
'from math.inc

Proc wheel2Deg

    Parameters Angle!
    Return (180 / Pi()) * Angle!

ENDPROC

Proc ArcTan2

    'Winkel from position form
    'If Objekt 1 To Objekt 2 look should, is the Winkel this:
    'ArcTan2(x1 - x2, y1 - y2)
    'around the Bogenmaß in strain umzuwandeln can ArcTan2 uses go
    Parameters x!, y!
    Declare result!

    if (y! > 0.0)

        result! = ArcTan(x!/y!)

    elseif (y! < 0.0) & (x! >= 0.0)

        result! = ArcTan(x!/y!) + Pi()

    elseif (y! < 0.0) & (x! < 0.0)

        result! = ArcTan(x!/y!) - Pi()

    elseif (y! = 0.0) & (x! > 0.0)

        result! = Pi() / 2.0

    elseif (y! = 0.0) & (x! < 0.0)

        result! = 0.0 - (Pi() / 2.0 )

    elseif (y! = 0.0) & (x! = 0.0)

        'no stood off, no direction, can with want abgefangen go
        result! = -1000

    endif

    Return result!

ENDPROC

Proc ArcTan4

    'ArcTan4: an Neuschöpfung -) everything in a inklusive performance Tweaks
    'The Vektoren must not self accounts go, it go
    'just two spots transfer, the Result is already in strain
    Parameters x1!, y1!, x2!, y2!
    Declare result!, x!, y!
    x! = x1! - x2!
    y! = y1! - y2!

    if (y! > 0.0)

        result! = ArcTan(x!/y!) * 57.2957795131

    elseif (y! < 0.0) & (x! >= 0.0)

        result! = (ArcTan(x!/y!) + 3.1415926535897932) * 57.2957795131

    elseif (y! < 0.0) & (x! < 0.0)

        result! = (ArcTan(x!/y!) - 3.1415926535897932) * 57.2957795131

    elseif (y! = 0.0) & (x! > 0.0)

        result! = 1.57079632679 * 57.2957795131

    elseif (y! = 0.0) & (x! < 0.0)

        result! = -1.57079632679 * 57.2957795131

    elseif (y! = 0.0) & (x! = 0.0)

        'no stood off, no direction, can with want abgefangen go
        result! = -1000

    endif

    Return result!

ENDPROC

While isKey(27) = 0

    sleep 10
    oGL("clear")
    oGL("move",0,0,-2)
    'Mittelpunkt the Gesichts
    oGL("2D", 0, 0, -2, oglX&, oglY&)
    'the face (oglX&, oglY&) schaut to Mausposition (%mousex, %mousey)
    'zRot! = wheel2deg(ArcTan2(%mousex - oglX&, %mousey - oglY&))
    'or
    zRot! =ArcTan4(%mousex, %mousey, oglX&, oglY&)
    oGL("rotate",0,0,zRot!)
    oGL("texture",1,1)
    oGL("quad",1,1)
    oGL("show")

EndWhile