You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
86 lines
2.5 KiB
C++
86 lines
2.5 KiB
C++
/**********************************************************************
|
|
|
|
Arcball.h
|
|
|
|
A C++ class that implements the Arcball, as described by Ken
|
|
Shoemake in Graphics Gems IV.
|
|
This class takes as input mouse events (mouse down, mouse drag,
|
|
mouse up), and creates the appropriate quaternions and 4x4 matrices
|
|
to represent the rotation given by the mouse.
|
|
|
|
This class is used as follows:
|
|
- initialize [either in the constructor or with set_params()], the
|
|
center position (x,y) of the arcball on the screen, and the radius
|
|
- on mouse down, call mouse_down(x,y) with the mouse position
|
|
- as the mouse is dragged, repeatedly call mouse_motion() with the
|
|
current x and y positions. One can optionally pass in the current
|
|
state of the SHIFT, ALT, and CONTROL keys (passing zero if keys
|
|
are not pressed, non-zero otherwise), which constrains
|
|
the rotation to certain axes (X for CONTROL, Y for ALT).
|
|
- when the mouse button is released, call mouse_up()
|
|
|
|
Axis constraints can also be explicitly set with the
|
|
set_constraints() function.
|
|
|
|
The current rotation is stored in the 4x4 float matrix 'rot'.
|
|
It is also stored in the quaternion 'q_now'.
|
|
|
|
------------------------------------------------------------------
|
|
|
|
Feb 25, 1998 - Paul Rademacher (rademach@cs.unc.edu)
|
|
|
|
**********************************************************************/
|
|
|
|
|
|
#ifndef _ARCBALL_H_
|
|
#define _ARCBALL_H_
|
|
|
|
|
|
#include "stdinc.h"
|
|
#include "algebra3.h"
|
|
#include "quaternion.h"
|
|
|
|
#ifdef __APPLE__
|
|
#include <GLUT/glut.h>
|
|
#else
|
|
#include <GL/glut.h>
|
|
#endif
|
|
|
|
class Arcball {
|
|
public:
|
|
Bool constraint_x, constraint_y;
|
|
vec2 center;
|
|
float radius, damp_factor;
|
|
int zero_increment;
|
|
|
|
vec3 constrain_vector( vec3 vector, vec3 axis );
|
|
vec3 mouse_to_sphere( vec2 p );
|
|
|
|
//public:
|
|
int is_mouse_down; /* true for down, false for up */
|
|
int is_spinning;
|
|
quat q_now, q_down, q_drag, q_increment;
|
|
vec2 down_pt;
|
|
mat4 rot, rot_increment;
|
|
mat4 *rot_ptr;
|
|
|
|
void set_damping( float d );
|
|
void idle( void );
|
|
void mouse_down( int x, int y );
|
|
void mouse_up( void );
|
|
void mouse_motion( int x, int y, int shift, int ctrl, int alt );
|
|
void mouse_motion( int x, int y );
|
|
void set_constraints( Bool constrain_x, Bool constrain_y );
|
|
void set_params( vec2 center, float radius );
|
|
void reset_mouse( void );
|
|
void init( void );
|
|
|
|
Arcball( void );
|
|
Arcball( mat4 *mtx );
|
|
Arcball( vec2 center, float radius );
|
|
};
|
|
|
|
|
|
#endif
|
|
|