# OpenGL Problem with quaternion based camera and object placing, possible cml problem

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For months I've been trying to get object and camera placing to work, and it feels like this should work, except that it is missing a character/sign somewhere causing everything to fail

The properties I'm trying to recreate are:
• In is positive Z
• Right is positive X
• Up is positive Y
• Identity quaternion is facing In/positive z
This is how I create my projection matrix:
gluPerspective(camera.fov, aspect, camera.znear, camera.zfar); pwnAssert_NoGLError();

This is how I build my camera matrix:
// camera.rotation is a quaternion representing the rotation of the camera, camera.position.vec is the vector of the object const math::mat44 fixOpenGlNegativeZ = cmat44(RightHandAround(Up(), Angle::FromDegrees(180))); : mat( fixOpenGlNegativeZ * cmat44(camera.rotation) * cmat44(vec3(-X(camera.position.vec), -Y(camera.position.vec), Z(camera.position.vec))) )

This is how I generate the modelview matrix per object that is sent to gl through LoadMatrix
// mat is the camera matrix above, pos is the vec3 worldspace position and rot is a quaterion representing the rotation of the object return mat * math::cmat44(pos) * math::cmat44(rot)

My maths is cml based and here are their definitions:
typedef cml::vector<real, cml::fixed<3> > vec3; typedef cml::quaternion<real, cml::fixed<>, cml::vector_first, cml::positive_cross> quat; typedef cml::matrix<real, cml::fixed<4,4>, cml::col_basis, cml::col_major > mat44;

Along cml I have a few wrappers, mainly ©onverter functions beginning with c and ending with the resulting type, like cmat44 converting it's argument to a 4x4 matrix.
cmat44(vec3) = cml::matrix_set_translation cmat44(quat) = cml::matrix_rotation_quaternion RightHandAround = cml::quaternion_rotation_axis_angle

To get right of a quaternion I do:
// v is global Right(positive X) and q is the quaternion const quat r = q * quat(v, 0) * math::GetConjugate(q); return cvec3(r); // ignores w // the vector is normalized later before it's used

If anyone can point out what I'm doing wrong or offer suggestions I would be glad

edit: slighty changed topictitle to better describe the problem

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I've might have a working implementation now. I changed fixOpenGlNegativeZ to a negative z scaling matrix since I probably want what is called a left handed coordinate space and the OpenGL faq recommends doing this.
Then I changed my lookat from
quaternion_rotation_aim_at(ret, from, to, up, cml::axis_order_zyx);
to
cml::matrix_look_at_LH(mat, from, to, up); cml::quaternion_rotation_matrix(ret,mat);

and that apparently fixed the problems(I still don't know what the difference between those functions are). that I at the moment can detect. I will have to do some more testing but for it seems to be working

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