hwt_travel_cube - get travel times
int hwt_travel_cube(int *n,float *o,float *d,float *shot,float aimi,float aima,
float oi,float si,int ni, float sa, int na,float st,int nt,float *vel,
int quick, float *travel)
Dimensions of elements in velocity cube (3)
First element of velocity cube (3)
Sampling of velocity cube velocity cube (3)
Location of shot
Inclination
Azimuth
First aperture angle
Sampling of aperture
Number of half aperture angles
Sampling of radial steps
Number of radial steps
Sampling in time
Number of time samples
Velocity
Whether or not do quick interpolation
Travel time cube
Do Huygens wavefront tracing and then interpolate
hwt_trace_rays, Hwt3d
septravel