Rotation Matrix ??

[marco]

hi @all

i'v a problem with the rotation in degrees

if have an up and an dir vector

up is not everytime 0,1,0
dir is the direction

now i rotate dir around up (that works)

but how do i get now the rotation of the object in degrees ?, so that the object rotates to even this dir ???

thx

[arras]

use: matrix4::getRotationDegrees()

you may aply this fixes before using it:

http://irrlicht.sourceforge.net/phpBB2/ ... php?t=2234

http://irrlicht.sourceforge.net/phpBB2/ ... php?t=2458

BTW: howe do you rotate around up vector?

[Guest]

i'll try the fixes

i rotat around th up with :

Code: Select all

dir=
		(dir+
			dir.crossProduct(up.normalize())	*sin(2*PI*rotate/360)).normalize().crossProduct(up.normalize())
			.crossProduct(up.normalize()).normalize()*-1;

that works but how do i now rotate the (for example car) on the screen to reflect these rotations ( up ist die up vector from the street and dir the moving direction) it moves, but the car shows to everywhere , but not to dir

[marco]

Code: Select all

matrix4 h;
		h.buildCameraLookAtMatrixRH(car->pos,car->pos+car->dir,car->up);
		h.makeInverse();
		car->rotation_angle=h.getRotationDegrees();
		car_object->setRotation(car->rotation_angle);

does exactly what i want

:):)