/* gltrackball, Copyright (c) 2002-2017 Jamie Zawinski <jwz@jwz.org>
* GL-flavored wrapper for trackball.c
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation. No representations are made about the suitability of this
* software for any purpose. It is provided "as is" without express or
* implied warranty.
*/
#ifndef __GLTRACKBALL_H__
#define __GLTRACKBALL_H__
typedef struct trackball_state trackball_state;
/* Returns a trackball_state object, which encapsulates the stuff necessary
to make dragging the mouse on the window of a GL program do the right thing.
*/
extern trackball_state *gltrackball_init (int ignore_device_rotation_p);
/* Begin tracking the mouse: Call this when the mouse button goes down.
x and y are the mouse position relative to the window.
w and h are the size of the window.
*/
extern void gltrackball_start (trackball_state *, int x, int y, int w, int h);
/* Track the mouse: Call this each time the mouse moves with the button down.
x and y are the new mouse position relative to the window.
w and h are the size of the window.
*/
extern void gltrackball_track (trackball_state *, int x, int y, int w, int h);
/* Stop tracking the mouse: Call this when the mouse button goes up.
*/
extern void gltrackball_stop (trackball_state *);
/* Execute the rotations current encapsulated in the trackball_state:
this does something analagous to glRotatef().
*/
extern void gltrackball_rotate (trackball_state *);
/* Call this when a mouse-wheel click is detected.
Clicks act like horizontal or vertical drags.
Percent is the length of the drag as a percentage of the screen size.
Button is 'Button4' or 'Button5' (for the vertical wheel)
or 'Button5' or 'Button6' (for the horizontal wheel).
If `flip_p' is true, swap the horizontal and vertical axes.
*/
void gltrackball_mousewheel (trackball_state *ts,
int button, int percent, int flip_p);
/* Return the quaternion encapsulated by the trackball state.
*/
extern void gltrackball_get_quaternion (trackball_state *ts, float q[4]);
/* Reset the trackball to the default unrotated state,
plus an optional initial rotation.
*/
extern void gltrackball_reset (trackball_state *ts, float x, float y);
/* A utility function for event-handler functions:
Handles the various motion and click events related to trackballs.
Returns True if the event was handled.
*/
extern Bool gltrackball_event_handler (XEvent *,
trackball_state *,
int window_width, int window_height,
Bool *button_down_p);
#endif /* __GLTRACKBALL_H__ */