Plug-In Power Pack for Netscape Communicator/Plug-In Power Pack for Netscape Communicator.iso/plugins/dataviews/dvtools/demos/telecomdemo/move_win.c

C/C++ Source or Header | 1997-05-08 | 5.3 KB | 191 lines

#ifndef lint
static char SccsId[]= "@(#)move_win.c    V1.6    3/17/95";
#endif

/*
 |    File name: move_win.c
 |========================================================================
 |
 |    Copyright (c) 1990 -- V.I. Corporation
 |
 |========================================================================
 */

#include "simulate.h"
#include "tlc_fundecl.h"


/***************** Begin Function Declarations *************/
LOCAL  void move_window V_P_((OBJECT location, DV_POINT *screen_lim, RECTANGLE *curr_pos, RECTANGLE *rel));
/***************** End Function Declarations *************/

/*
 *   Global and local function declarations.
 */
LOCAL VOID move_window ();

/*
 *   MoveDrawport -- move a rectangle withing the screen.  Take a rectangle
 *     that describes the position of a drawport and a location object the is
 *     the current position of the cursor, and allow the user to move an
 *     outline of the drawport until he releases the button he's holding.
 */
/* ARGSUSED */
void
MoveDrawport (screen, curr_pos, orig_location)
     OBJECT screen;
     RECTANGLE *curr_pos;
     OBJECT orig_location;
{
  DV_POINT *ptr, *screen_lim;
  RECTANGLE rel;
  INT indx;
  OBJECT location;
  DV_BOOL done = NO;

  /*
   *   Get the current position of the cursor and compute its position
   *     relative to the corners of the rectangle.
   */
  ptr = VOloScpGet (orig_location);
  rel.ll.x = ptr->x - curr_pos->ll.x;
  rel.ll.y = ptr->y - curr_pos->ll.y;
  rel.ur.x = curr_pos->ur.x - ptr->x;
  rel.ur.y = curr_pos->ur.y - ptr->y;
  screen_lim = VOscSize ();

  /*
   *   Use a medium gray as the outline color of the rectangle and set the
   *     drawing mode to XOR.
   */
  (VOID) GRrgbtoindex (128, 128, 128, &indx);
  (VOID) GRcolor (indx);
  (VOID) GRset (V_DRAW_FUNCTION, V_XOR, V_END_OF_LIST);
  (VOID) GRrectangle (&curr_pos->ll, &curr_pos->ur);
  (VOID) VOscWinEventMask ((ULONG) V_ADD_TO_MASK |
                           V_MOTIONNOTIFY |
                           V_BUTTONRELEASE |
                           V_LEAVENOTIFY,
                           0L);

  /*
   *   Continue polling the cursor, moving the outline of the rectangle as
   *     necessary, until the button is released or the cursor leaves the
   *     window.
   */
  while (!done)
    {
      location = VOscWinEventPoll ((INT) V_WAIT);
      switch (VOloType (location))
        {
        case V_MOTIONNOTIFY:
          move_window (location, screen_lim, curr_pos, &rel);
          break;
        case V_BUTTONRELEASE:
          move_window (location, screen_lim, curr_pos, &rel);
          done = YES;
          break;
        case V_LEAVENOTIFY:
          done = YES;
          break;
        default:
          break;
        }
    }

  /*
   *   Erase the last instance of the outline and restore the drawing mode.
   */
  (VOID) GRrectangle (&curr_pos->ll, &curr_pos->ur);
  (VOID) GRset (V_DRAW_FUNCTION, V_COPY, V_END_OF_LIST);
}


/*
 *   move_window -- use the new location object to see if the outline
 *     of the rectangle needs to be moved.
 */
LOCAL void
move_window (location, screen_lim, curr_pos, rel)
     OBJECT location;
     DV_POINT *screen_lim;
     RECTANGLE *curr_pos;
     RECTANGLE *rel;
{
  DV_POINT *ptr;
  DV_BOOL change = NO;
  RECTANGLE new_pos;

  /*
   *   Get the screen position of the cursor, and check to see if the
   *     the left and right sides of the box are within the limits of
   *     the screen.
   */
  ptr = VOloScpGet (location);
  if (ptr->x - rel->ll.x > 0 && ptr->x + rel->ur.x < screen_lim->x)
    {
      new_pos.ll.x = ptr->x - rel->ll.x;
      new_pos.ur.x = ptr->x + rel->ur.x;
      change = YES;
    }

  /*
   *   If one of the sides is off the screen, then determine which side it
   *     is and adjust it so that it's just at the screen limit.
   */
  else if (ptr->x - rel->ll.x <= 0)
    {
      new_pos.ll.x = 0;
      new_pos.ur.x = rel->ll.x + rel->ur.x;
    }
  else
    {
      new_pos.ur.x = screen_lim->x;
      new_pos.ll.x = screen_lim->x - rel->ur.x - rel->ll.x;
    }

  /*
   *   Do the same limit checking for the top and bottom of the box.
   */
  if (ptr->y - rel->ll.y > 0 && ptr->y + rel->ur.y < screen_lim->y)
    {
      new_pos.ll.y = ptr->y - rel->ll.y;
      new_pos.ur.y = ptr->y + rel->ur.y;
      change = YES;
    }
  else if (ptr->y - rel->ll.y <= 0)
    {
      new_pos.ll.y = 0;
      new_pos.ur.y = rel->ll.y + rel->ur.y;
    }
  else
    {
      new_pos.ur.y = screen_lim->y;
      new_pos.ll.y = screen_lim->y - rel->ur.y - rel->ll.y;
    }

  /*
   *   Check to see if the box has moved at all and if it has then
   *     erase the old image of the box and draw a new one at the new
   *     position.
   */
  if (new_pos.ll.x != curr_pos->ll.x)
    change = YES;
  if (new_pos.ll.y != curr_pos->ll.y)
    change = YES;
  if (new_pos.ur.x != curr_pos->ur.x)
    change = YES;
  if (new_pos.ur.y != curr_pos->ur.y)
    change = YES;

  if (change)
    {
      (VOID) GRrectangle (&curr_pos->ll, &curr_pos->ur);
      (VOID) GRrectangle (&new_pos.ll, &new_pos.ur);
      curr_pos->ll.x = new_pos.ll.x;
      curr_pos->ll.y = new_pos.ll.y;
      curr_pos->ur.x = new_pos.ur.x;
      curr_pos->ur.y = new_pos.ur.y;
    }
}