How do I Get the X,Z Coordinate from the Mouse Position

[Fingers]

Hi All,

If I'm looking at a spot in space, how do I get the x,z coordinates of the intersection of the Mouse cursor on the Y-Plane set at 0??

Thx in Advance.

[Guest]

ehm, what??

get 2d mouse position:

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position2d<s32> position = yourCursorControl->getPosition();

get 3d mouse position:

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vector3df get3DCursorPosition(ITriangleSelector* TriangleSelector, ICursorControl* CursorControl, ISceneManager* SceneManager)
{
	vector3df	Result;
	triangle3df	Triangle;
	line3d<f32>	Ray;

	Ray = SceneManager->getSceneCollisionManager()->
		  getRayFromScreenCoordinates(CursorControl->getPosition(),
		  SceneManager->getActiveCamera());

	CollisionManager->getCollisionPoint(Ray, TriangleSelector, Result, Triangle);

	return Result;
}

i hope that can help you

[Fingers]

well it sorta pointed me in the right direction, and after looking around the internet, I came up with this,

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bool Runner::OnEvent( SEvent event ){
	bool retValue = false;
	if( event.EventType == EET_MOUSE_INPUT_EVENT ){
		if( event.MouseInput.Event == EMIE_MOUSE_MOVED ) {
			ray = smgr->getSceneCollisionManager()->getRayFromScreenCoordinates(
				position2d<s32>(event.MouseInput.X, event.MouseInput.Y) );
			point = lineIntersectWithPlane( ray, vector3df(0,0,0), vector3df(0,1,0) );
			retValue=true;
		}
	}

	return retValue;
}

vector3df Runner::lineIntersectWithPlane( line3d<f32> S, vector3df origin, vector3df Pn ) {
	vector3df u = S.end - S.start;
	vector3df w = S.start - origin;

    float D = Pn.dotProduct(u);
    float N = -Pn.dotProduct(w);

    if(fabs(D) < 0.00000001) {
        if (N == 0)
            return vector3df(0,0,0);
        else
            return vector3df(0,0,0);
    }
    float sI = N / D;
    if (sI < 0 || sI > 1)
        return vector3df(0,0,0);

	u.X *= sI;
	u.Y *= sI;
	u.Z *= sI;

	return S.start + u;
}

Which gives me the X,Z coordinates on the Y-Plane without having any scene nodes created yet.