debian man page for s3d_angle_to_cam

S3D_ANGLE_TO_CAM(3)						    s3d Manual						       S3D_ANGLE_TO_CAM(3)

NAME
       s3d_angle_to_cam - calculate angle between vector and cam

SYNOPSIS
       #include <s3d.h>

       float s3d_angle_to_cam(const float obj_pos[], const float cam_pos[], float *angle_rad);

DESCRIPTION
       Given obj_pos and cam_pos in the format float[3], angle_rad about which angle the object should be rotated around the y-axis so that it
       faces the camera. This might become handy if you have some text floating in space and want it to face the camera.
       http://en.wikipedia.org/wiki/Vector_(spatial)

AUTHOR
       Simon Wunderlich
	   Author of s3d

s3d															       S3D_ANGLE_TO_CAM(3)