/*----------------------------------------------------------------------------
 *   fly.c
 *  
 *    This file contains the routines to animate the arm by doing a simple
 * flypast by incrementally altering the viewpoint.  A double buffered
 * Intuition screen is used.
 *----------------------------------------------------------------------------
*/

#include  <exec/types.h>
#include  <lattice/stdio.h>
#include  <intuition/intuition.h>
#include  "defs.h"
#include  "ds.h"

extern struct RasInfo   *ri ;
extern struct BitMap    b,  b2 ;
extern struct RastPort  rp,  rp2 ;
extern struct Screen    *screen ;
extern ROTATION_INFO    rot_info ;

int  flypast_trans [NUM_FLYPAST_VPOINTS] [4][4] ; /* array of pre-calculated */
                                                  /* view transformations */

open_db_screen_for_flypast ()
{
 int  *save_trans  = rot_info.curr_view_trans ;
 int  i ;

 /*--------------------------------------------------------------------------
  *   This routine draws a frame, updates the viewing transformation, then
  * switches screen memory to the the bitplanes just drawn into
  * (via its rastport).  The swapped out screen memory is then drawn into for
  * the next frame, and the process repeats until the required number of frames
  * are drawn.
  *   The flight path is more or less a 90 degree circular sweep in XY, with
  * a linear increment in Z.
  *---------------------------------------------------------------------------
 */
 screen->RastPort.BitMap  = &b2 ;     /* put 2nd set of bitplanes */
 ri->BitMap  = &b2 ;                  /* on the screen */
 MakeScreen (screen) ;
 RethinkDisplay () ;

 for (i = 0;  i < NUM_FLYPAST_VPOINTS - 1;  i = i + 2)   {

                                        /* get next view transformation */
    rot_info.curr_view_trans  = (int *)flypast_trans [i] ;
    transform_links () ;                /* new eye coordinates for view */
    set_screen_coords () ;
    draw_image (&rp) ;                  /* draw into 1st set of bit planes */

    screen->RastPort.BitMap  = &b ;     /* swap screen memory to 1st screen */
    ri->BitMap  = &b ;
    MakeScreen (screen) ;
    RethinkDisplay () ;
                                       /* get next view transformation */
    rot_info.curr_view_trans  = (int *)flypast_trans [i+1] ;
    transform_links () ;               /* new eye coordinates for view */
    set_screen_coords () ;
    draw_image (&rp2) ;                /* draw into 2nd set of bit planes */

    screen->RastPort.BitMap  = &b2 ;   /* swap screen memory to 1st screen */
    ri->BitMap  = &b2 ;
    MakeScreen (screen) ;
    RethinkDisplay () ;
 }

 SetRast (&rp, COLOR0) ;
 for (i = 0;  i < 150000;  ++i)        /* let user have a look at last frame */
     ;

 screen->RastPort.BitMap  = &b ;
 ri->BitMap  = &b ;
 MakeScreen (screen) ;
 RethinkDisplay () ;
 SetRast (&rp2, COLOR0) ;
 rot_info.curr_view_trans  = save_trans ;
}


init_flypast_trans ()
{
 float  flypast_viewpoint [3] ;
 static float  fly_coords [] =
            { 10.0, 50.0, 90.0, 140.0, 190.0, 230.0, 280.0,
              320.0, 360.0, 400.0, 430.0, 450.0, 470.0, 480.0, 490.0, 500.0
            } ;
 float  z = 200.0 ;
 int    i,  j = 0,  k = 15 ;
 
 /*---------------------------------------------------------------------------
  *   Initialize (once at program start) the viewing transformations for the
  * flypast, in order to speed up animation.
  *   The flight path is more or less a 90 degree circular sweep in XY, with
  * a linear increment in Z.
  *---------------------------------------------------------------------------
 */
 for (i = 0;  i < NUM_FLYPAST_VPOINTS;  ++i)   {

     flypast_viewpoint [X]  = fly_coords [j++] ;
     flypast_viewpoint [Y]  = fly_coords [k--] ;
     flypast_viewpoint [Z]  =  z ;
     z  = z + 20.0 ;

     viewing_transformation (flypast_viewpoint, flypast_trans [i]) ;
 }
}