I've been trying for days to rotate a cube based on the mouse position just like this one:
http://images.flashkit.com/movies/3D/Engines/Real-Tim-Ryan_Whe-1937/Real-Tim-Ryan_Whe-1937.swf
I can't get it to do a full 360, it just kinda wiggles... I think i have the formula right, but I believe I'm missing something.
Formula(?)
y1 = oldY * cos(newX) + oldZ * sin(newX)
z1 = oldY * -sin(newX) + oldZ * cos(newX)
x1 = oldX * cos(newY) + z1 * -sin(newY)
z2 = oldX * sin(newX) + z1 * cos(newY)
x2 = x1 * cos(-newX) + y1 * sin(-newX)
y2 = x1 * -sin(-newX) + y1 * cos(-newX)
I'm rendering the cube on a 500x500 form, with the mouse relative to the center. I scaled the mouse position by 1000, so the min/max value is -/+ 0.25.
I know I have to track the angle, and update it based on the mouse position, but after looking at the forums and googling I'm still confused..
heres my current code:
//Globals
public float mousePosX = .25f;
public float mousePosY = .25f;
public float oldPosX = .25f;
public float oldPosY = .25f;
public float oldPosZ = .25f;
//-------------------------------------------------------------------------------
public void UpdateMatrices()
{
//Rotate the cube, based on the mouse location
if (oldPosX == 0) //Testing
{
oldPosX = mousePosX;
oldPosY = mousePosY;
oldPosZ = -mousePosX;
}
float y1 = (float) (oldPosY * Math.Cos((double) mousePosX) + oldPosZ * Math.Sin((double) mousePosX));
float z1 = (float) (oldPosY * -Math.Sin((double) mousePosX) + oldPosZ * Math.Cos((double) mousePosX));
float x1 = (float) (oldPosX * Math.Cos((double) mousePosY) + z1 * -Math.Sin((double) mousePosY));
float z2 = (float) (oldPosX * Math.Sin((double) mousePosY) + z1 * Math.Cos((double) mousePosY));
float x2 = (float) (x1 * Math.Cos((double) -mousePosX) + y1 * Math.Sin((double) -mousePosX));
float y2 = (float) (x1 * -Math.Sin((double) -mousePosX) + y1 * Math.Cos((double) -mousePosX));
oldPosX = x2;
oldPosY = y2;
oldPosZ = z2;
device.Transform.World = Matrix.RotationYawPitchRoll(x2,y2,-x2);
device.Transform.View = Matrix.LookAtLH( new Vector3( 0.0f, 3.0f,-5.0f ), new Vector3( 0.0f, 0.0f, 0.0f ), new Vector3( 0.0f, 1.0f, 0.0f ) );
device.Transform.Projection = Matrix.PerspectiveFovLH( (float)Math.PI / 4, 1.0f, 1.0f, 100.0f );
}
Its C#, but should be easy to understand.
[edited by - _untitled on November 30, 2003 7:05:45 PM]
