def camera_pitch(self,theta):
        pointing = self.focus - self.location
        axis = np.cross(self.up, pointing)
        newpointing = self.rotate_vector(pointing, axis, theta)
        self.focus = newpointing + self.location
        self.up = np.cross(newpointing, axis)
        self.up /= np.sqrt(self.up.dot(self.up))
dataset/ETHPy150Open grantbrown/laspy/laspy/glviewer.py/pcl_image.camera_pitch/original