WebSVN – gelsvn – Diff – /trunk/src/GLGraphics/QuatTrackBall.cpp


/* ----------------------------------------------------------------------- *
 * This file is part of GEL, http://www.imm.dtu.dk/GEL
 * Copyright (C) the authors and DTU Informatics
 * For license and list of authors, see ../../doc/intro.pdf
 * ----------------------------------------------------------------------- */
 
#include <iostream>
#include "../CGLA/CGLA.h"
#include "QuatTrackBall.h"
 
#include "gel_glu.h"
#include "GLViewController.h"
 
 
using namespace std;
using namespace CGLA;
 
namespace GLGraphics
{
    
    QuatTrackBall::QuatTrackBall(const Vec3f& _centre, 
			 float _eye_dist,
			 unsigned _width, 
			 unsigned _height):
	centre(_centre), width(_width), height(_height), 
	eye_dist(_eye_dist)
	{
	// This size should really be based on the distance from the center of
	// rotation to the point on the object underneath the mouse.  That
	// point would then track the mouse as closely as possible.  This is a
	// simple example, though, so that is left as an exercise.
	ballsize = 2.0f;
	screen_centre = Vec2i(width/2, height/2);
	qrot = Quatf(0.0, 0.0, 0.0, 1.0);
	qinc = Quatf(0.0, 0.0, 0.0, 1.0);
	trans = Vec2f(0.0, 0.0);
    }
    
    void QuatTrackBall::grab_ball(TrackBallAction act, const Vec2i& v)
    {
    if(v[0] < 0 || v[0] >= static_cast<int>(width)
       || v[1] < 0 || v[1] >= static_cast<int>(height))
      return;      
 
	set_position(scalePoint(v));
	current_action = act;
    }
    
    void QuatTrackBall::roll_ball(const Vec2i& v)
    {
    if(v[0] < 0 || v[0] >= static_cast<int>(width)
       || v[1] < 0 || v[1] >= static_cast<int>(height))
      return;      
 
	Vec2f w = scalePoint(v); 
	
	switch (current_action) 
        {
			case ROTATE_ACTION:
                rotate(w);
                break;
                
			case PAN_ACTION:
                pan(w);
                break;
                
			case ZOOM_ACTION:
                zoom(w);
                break;
            case NO_ACTION:
            default:
                break;
        }
	last_pos = w;
    }
    
    // Call this when the user does a mouse down.  
    // Stop the trackball glide, then remember the mouse
    // down point (for a future rotate, pan or zoom).
    void QuatTrackBall::set_position(const Vec2f& _last_pos) 
    {
	stop_spin();
	last_pos = _last_pos;
    }
    
    // Rotationaly spin the trackball by the current increment.
    // Use this to implement rotational glide.
    void QuatTrackBall::do_spin() 
    {
	qrot = qrot*qinc;
    }
    
    // Cease any rotational glide by zeroing the increment.
    void QuatTrackBall::stop_spin() 
    {
	qinc.set(0.0, 0.0, 0.0, 1.0);
    }
    
    void QuatTrackBall::rotate(const Vec2f& new_v) 
    {
	calcRotation(new_v);
	do_spin();	
    }
    
    void QuatTrackBall::pan(const Vec2f& new_v) 
    {
	trans += (new_v - last_pos) * Vec2f(eye_dist);
    }
    
    void QuatTrackBall::zoom(const Vec2f& new_v) 
    {
	eye_dist += (new_v[1] - last_pos[1]) * eye_dist;
	eye_dist = max(eye_dist, 0.01f);
    }
    
    void QuatTrackBall::calcRotation(const Vec2f& new_pos) 
    {
	// Check for zero rotation
	if (new_pos == last_pos) 
	    qinc = Quatf(0.0f, 0.0f, 0.0f, 1.0f);
	else
	{
		// Form two vectors based on input points, find rotation axis
		Vec3f p1 = Vec3f(new_pos[0], new_pos[1], projectToSphere(new_pos));
		Vec3f p2 = Vec3f(last_pos[0], last_pos[1], projectToSphere(last_pos));
        qinc.make_rot(normalize(p1), normalize(p2));
/*
		Vec3f q = cross(p1, p2);		// axis of rotation from p1 and p2 
		float L = sqrt(1.0f-dot(q,q) / (dot(p1,p1) * dot(p2,p2)));
		
		q.normalize();				// q' = axis of rotation 
		q *= sqrt((1 - L)/2);	// q' = q' * sin(phi)
		
		qinc.set(q[0],q[1],q[2],sqrt((1 + L)/2));
*/
	}
    }
    
    // Project an x,y pair onto a sphere of radius r OR a hyperbolic sheet
    // if we are away from the center of the sphere.
    float QuatTrackBall::projectToSphere(const Vec2f& v) 
    {
#ifndef M_SQRT_2
	  const double M_SQRT_2 = 0.707106781187;
#endif
 
      float d = v.length();
      float t = ballsize*M_SQRT_2;
      float z;
  
      // Inside sphere 
      if(d < ballsize) 
        z = sqrt(ballsize*ballsize - d*d);
      else if(d < t)
        z = 0.0;
      // On hyperbola 
      else 
        z = t*t/d;
 
      return z;
    }
    
    // Scales integer point to the range [-1, 1]
    Vec2f QuatTrackBall::scalePoint(const Vec2i& v) const
    {
	Vec2f w(v[0],height - v[1]);
	w -= Vec2f(screen_centre);
	w /= Vec2f(width,height);
	w = CGLA::v_min(Vec2f(1.0f), CGLA::v_max(Vec2f(-1), 2*w));
	return w; 
    }
    
    void QuatTrackBall::get_view_param(Vec3f& eye, Vec3f& _centre, Vec3f& up) const
    {
	up  = qrot.apply_unit(Vec3f(0,1,0));
	Vec3f right = qrot.apply(Vec3f(1,0,0));
	_centre = centre - up * trans[1] - right * trans[0]; 
	eye = qrot.apply_unit(Vec3f(0,0,1)*eye_dist) + _centre;
    }
    
    
    // Modify the current gl matrix by the trackball rotation and translation.
    void QuatTrackBall::set_gl_modelview() const
    {
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	Vec3f eye;
	Vec3f _centre;
	Vec3f up;
	get_view_param(eye, _centre, up);
	gluLookAt(eye[0], eye[1], eye[2],
		  _centre[0], _centre[1], _centre[2], 
		  up[0],up[1],up[2]);
    }
    
    bool QuatTrackBall::is_spinning() const
    {
	static const Quatf null_quat(0,0,0,1);
	if(!(qinc == null_quat))
	    return true;
	return false;
    }
}
 

Rev 601	Rev 609
1	`/* ----------------------------------------------------------------------- *`	1	`/* ----------------------------------------------------------------------- *`
2	`* This file is part of GEL, http://www.imm.dtu.dk/GEL`	2	`* This file is part of GEL, http://www.imm.dtu.dk/GEL`
3	`* Copyright (C) the authors and DTU Informatics`	3	`* Copyright (C) the authors and DTU Informatics`
4	`* For license and list of authors, see ../../doc/intro.pdf`	4	`* For license and list of authors, see ../../doc/intro.pdf`
5	`* ----------------------------------------------------------------------- */`	5	`* ----------------------------------------------------------------------- */`
6		6
7	`#include <iostream>`	7	`#include <iostream>`
8	`#include "../CGLA/CGLA.h"`	8	`#include "../CGLA/CGLA.h"`
9	`#include "QuatTrackBall.h"`	9	`#include "QuatTrackBall.h"`
10		10
11	`#include "gel_glu.h"`	11	`#include "gel_glu.h"`
12	`#include "GLViewController.h"`	12	`#include "GLViewController.h"`
13		13
14		14
15	`using namespace std;`	15	`using namespace std;`
16	`using namespace CGLA;`	16	`using namespace CGLA;`
17		17
18	`namespace GLGraphics`	18	`namespace GLGraphics`
19	`{`	19	`{`
20		20
21	`QuatTrackBall::QuatTrackBall(const Vec3f& _centre,`	21	`QuatTrackBall::QuatTrackBall(const Vec3f& _centre,`
22	`float _eye_dist,`	22	`float _eye_dist,`
23	`unsigned _width,`	23	`unsigned _width,`
24	`unsigned _height):`	24	`unsigned _height):`
25	`centre(_centre), width(_width), height(_height),`	25	`centre(_centre), width(_width), height(_height),`
26	`eye_dist(_eye_dist)`	26	`eye_dist(_eye_dist)`
27	`{`	27	`{`
28	`// This size should really be based on the distance from the center of`	28	`// This size should really be based on the distance from the center of`
29	`// rotation to the point on the object underneath the mouse. That`	29	`// rotation to the point on the object underneath the mouse. That`
30	`// point would then track the mouse as closely as possible. This is a`	30	`// point would then track the mouse as closely as possible. This is a`
31	`// simple example, though, so that is left as an exercise.`	31	`// simple example, though, so that is left as an exercise.`
32	`ballsize = 2.0f;`	32	`ballsize = 2.0f;`
33	`screen_centre = Vec2i(width/2, height/2);`	33	`screen_centre = Vec2i(width/2, height/2);`
34	`qrot = Quatf(0.0, 0.0, 0.0, 1.0);`	34	`qrot = Quatf(0.0, 0.0, 0.0, 1.0);`
35	`qinc = Quatf(0.0, 0.0, 0.0, 1.0);`	35	`qinc = Quatf(0.0, 0.0, 0.0, 1.0);`
36	`trans = Vec2f(0.0, 0.0);`	36	`trans = Vec2f(0.0, 0.0);`
37	`}`	37	`}`
38		38
39	`void QuatTrackBall::grab_ball(TrackBallAction act, const Vec2i& v)`	39	`void QuatTrackBall::grab_ball(TrackBallAction act, const Vec2i& v)`
40	`{`	40	`{`
41	`if(v[0] < 0 \|\| v[0] >= static_cast<int>(width)`	41	`if(v[0] < 0 \|\| v[0] >= static_cast<int>(width)`
42	`\|\| v[1] < 0 \|\| v[1] >= static_cast<int>(height))`	42	`\|\| v[1] < 0 \|\| v[1] >= static_cast<int>(height))`
43	`return;`	43	`return;`
44		44
45	`set_position(scalePoint(v));`	45	`set_position(scalePoint(v));`
46	`current_action = act;`	46	`current_action = act;`
47	`}`	47	`}`
48		48
49	`void QuatTrackBall::roll_ball(const Vec2i& v)`	49	`void QuatTrackBall::roll_ball(const Vec2i& v)`
50	`{`	50	`{`
51	`if(v[0] < 0 \|\| v[0] >= static_cast<int>(width)`	51	`if(v[0] < 0 \|\| v[0] >= static_cast<int>(width)`
52	`\|\| v[1] < 0 \|\| v[1] >= static_cast<int>(height))`	52	`\|\| v[1] < 0 \|\| v[1] >= static_cast<int>(height))`
53	`return;`	53	`return;`
54		54
55	`Vec2f w = scalePoint(v);`	55	`Vec2f w = scalePoint(v);`
56		56
57	`switch (current_action)`	57	`switch (current_action)`
58	`{`	58	`{`
59	`case ROTATE_ACTION:`	59	`case ROTATE_ACTION:`
60	`rotate(w);`	60	`rotate(w);`
61	`break;`	61	`break;`
62		62
63	`case PAN_ACTION:`	63	`case PAN_ACTION:`
64	`pan(w);`	64	`pan(w);`
65	`break;`	65	`break;`
66		66
67	`case ZOOM_ACTION:`	67	`case ZOOM_ACTION:`
68	`zoom(w);`	68	`zoom(w);`
69	`break;`	69	`break;`
-		70	`case NO_ACTION:`
-		71	`default:`
-		72	`break;`
70	`}`	73	`}`
71	`last_pos = w;`	74	`last_pos = w;`
72	`}`	75	`}`
73		76
74	`// Call this when the user does a mouse down.`	77	`// Call this when the user does a mouse down.`
75	`// Stop the trackball glide, then remember the mouse`	78	`// Stop the trackball glide, then remember the mouse`
76	`// down point (for a future rotate, pan or zoom).`	79	`// down point (for a future rotate, pan or zoom).`
77	`void QuatTrackBall::set_position(const Vec2f& _last_pos)`	80	`void QuatTrackBall::set_position(const Vec2f& _last_pos)`
78	`{`	81	`{`
79	`stop_spin();`	82	`stop_spin();`
80	`last_pos = _last_pos;`	83	`last_pos = _last_pos;`
81	`}`	84	`}`
82		85
83	`// Rotationaly spin the trackball by the current increment.`	86	`// Rotationaly spin the trackball by the current increment.`
84	`// Use this to implement rotational glide.`	87	`// Use this to implement rotational glide.`
85	`void QuatTrackBall::do_spin()`	88	`void QuatTrackBall::do_spin()`
86	`{`	89	`{`
87	`qrot = qrot*qinc;`	90	`qrot = qrot*qinc;`
88	`}`	91	`}`
89		92
90	`// Cease any rotational glide by zeroing the increment.`	93	`// Cease any rotational glide by zeroing the increment.`
91	`void QuatTrackBall::stop_spin()`	94	`void QuatTrackBall::stop_spin()`
92	`{`	95	`{`
93	`qinc.set(0.0, 0.0, 0.0, 1.0);`	96	`qinc.set(0.0, 0.0, 0.0, 1.0);`
94	`}`	97	`}`
95		98
96	`void QuatTrackBall::rotate(const Vec2f& new_v)`	99	`void QuatTrackBall::rotate(const Vec2f& new_v)`
97	`{`	100	`{`
98	`calcRotation(new_v);`	101	`calcRotation(new_v);`
99	`do_spin();`	102	`do_spin();`
100	`}`	103	`}`
101		104
102	`void QuatTrackBall::pan(const Vec2f& new_v)`	105	`void QuatTrackBall::pan(const Vec2f& new_v)`
103	`{`	106	`{`
104	`trans += (new_v - last_pos) * Vec2f(eye_dist);`	107	`trans += (new_v - last_pos) * Vec2f(eye_dist);`
105	`}`	108	`}`
106		109
107	`void QuatTrackBall::zoom(const Vec2f& new_v)`	110	`void QuatTrackBall::zoom(const Vec2f& new_v)`
108	`{`	111	`{`
109	`eye_dist += (new_v[1] - last_pos[1]) * eye_dist;`	112	`eye_dist += (new_v[1] - last_pos[1]) * eye_dist;`
110	`eye_dist = max(eye_dist, 0.01f);`	113	`eye_dist = max(eye_dist, 0.01f);`
111	`}`	114	`}`
112		115
113	`void QuatTrackBall::calcRotation(const Vec2f& new_pos)`	116	`void QuatTrackBall::calcRotation(const Vec2f& new_pos)`
114	`{`	117	`{`
115	`// Check for zero rotation`	118	`// Check for zero rotation`
116	`if (new_pos == last_pos)`	119	`if (new_pos == last_pos)`
117	`qinc = Quatf(0.0f, 0.0f, 0.0f, 1.0f);`	120	`qinc = Quatf(0.0f, 0.0f, 0.0f, 1.0f);`
118	`else`	121	`else`
119	`{`	122	`{`
120	`// Form two vectors based on input points, find rotation axis`	123	`// Form two vectors based on input points, find rotation axis`
121	`Vec3f p1 = Vec3f(new_pos[0], new_pos[1], projectToSphere(new_pos));`	124	`Vec3f p1 = Vec3f(new_pos[0], new_pos[1], projectToSphere(new_pos));`
122	`Vec3f p2 = Vec3f(last_pos[0], last_pos[1], projectToSphere(last_pos));`	125	`Vec3f p2 = Vec3f(last_pos[0], last_pos[1], projectToSphere(last_pos));`
123	`qinc.make_rot(normalize(p1), normalize(p2));`	126	`qinc.make_rot(normalize(p1), normalize(p2));`
124	`/*`	127	`/*`
125	`Vec3f q = cross(p1, p2); // axis of rotation from p1 and p2`	128	`Vec3f q = cross(p1, p2); // axis of rotation from p1 and p2`
126	`float L = sqrt(1.0f-dot(q,q) / (dot(p1,p1) * dot(p2,p2)));`	129	`float L = sqrt(1.0f-dot(q,q) / (dot(p1,p1) * dot(p2,p2)));`
127		130
128	`q.normalize(); // q' = axis of rotation`	131	`q.normalize(); // q' = axis of rotation`
129	`q = sqrt((1 - L)/2); // q' = q' sin(phi)`	132	`q = sqrt((1 - L)/2); // q' = q' sin(phi)`
130		133
131	`qinc.set(q[0],q[1],q[2],sqrt((1 + L)/2));`	134	`qinc.set(q[0],q[1],q[2],sqrt((1 + L)/2));`
132	`*/`	135	`*/`
133	`}`	136	`}`
134	`}`	137	`}`
135		138
136	`// Project an x,y pair onto a sphere of radius r OR a hyperbolic sheet`	139	`// Project an x,y pair onto a sphere of radius r OR a hyperbolic sheet`
137	`// if we are away from the center of the sphere.`	140	`// if we are away from the center of the sphere.`
138	`float QuatTrackBall::projectToSphere(const Vec2f& v)`	141	`float QuatTrackBall::projectToSphere(const Vec2f& v)`
139	`{`	142	`{`
140	`#ifndef M_SQRT_2`	143	`#ifndef M_SQRT_2`
141	`const double M_SQRT_2 = 0.707106781187;`	144	`const double M_SQRT_2 = 0.707106781187;`
142	`#endif`	145	`#endif`
143		146
144	`float d = v.length();`	147	`float d = v.length();`
145	`float t = ballsize*M_SQRT_2;`	148	`float t = ballsize*M_SQRT_2;`
146	`float z;`	149	`float z;`
147		150
148	`// Inside sphere`	151	`// Inside sphere`
149	`if(d < ballsize)`	152	`if(d < ballsize)`
150	`z = sqrt(ballsizeballsize - dd);`	153	`z = sqrt(ballsizeballsize - dd);`
151	`else if(d < t)`	154	`else if(d < t)`
152	`z = 0.0;`	155	`z = 0.0;`
153	`// On hyperbola`	156	`// On hyperbola`
154	`else`	157	`else`
155	`z = t*t/d;`	158	`z = t*t/d;`
156		159
157	`return z;`	160	`return z;`
158	`}`	161	`}`
159		162
160	`// Scales integer point to the range [-1, 1]`	163	`// Scales integer point to the range [-1, 1]`
161	`Vec2f QuatTrackBall::scalePoint(const Vec2i& v) const`	164	`Vec2f QuatTrackBall::scalePoint(const Vec2i& v) const`
162	`{`	165	`{`
163	`Vec2f w(v[0],height - v[1]);`	166	`Vec2f w(v[0],height - v[1]);`
164	`w -= Vec2f(screen_centre);`	167	`w -= Vec2f(screen_centre);`
165	`w /= Vec2f(width,height);`	168	`w /= Vec2f(width,height);`
166	`w = CGLA::v_min(Vec2f(1.0f), CGLA::v_max(Vec2f(-1), 2*w));`	169	`w = CGLA::v_min(Vec2f(1.0f), CGLA::v_max(Vec2f(-1), 2*w));`
167	`return w;`	170	`return w;`
168	`}`	171	`}`
169		172
170	`void QuatTrackBall::get_view_param(Vec3f& eye, Vec3f& _centre, Vec3f& up) const`	173	`void QuatTrackBall::get_view_param(Vec3f& eye, Vec3f& _centre, Vec3f& up) const`
171	`{`	174	`{`
172	`up = qrot.apply_unit(Vec3f(0,1,0));`	175	`up = qrot.apply_unit(Vec3f(0,1,0));`
173	`Vec3f right = qrot.apply(Vec3f(1,0,0));`	176	`Vec3f right = qrot.apply(Vec3f(1,0,0));`
174	`_centre = centre - up * trans[1] - right * trans[0];`	177	`_centre = centre - up * trans[1] - right * trans[0];`
175	`eye = qrot.apply_unit(Vec3f(0,0,1)*eye_dist) + _centre;`	178	`eye = qrot.apply_unit(Vec3f(0,0,1)*eye_dist) + _centre;`
176	`}`	179	`}`
177		180
178		181
179	`// Modify the current gl matrix by the trackball rotation and translation.`	182	`// Modify the current gl matrix by the trackball rotation and translation.`
180	`void QuatTrackBall::set_gl_modelview() const`	183	`void QuatTrackBall::set_gl_modelview() const`
181	`{`	184	`{`
182	`glMatrixMode(GL_MODELVIEW);`	185	`glMatrixMode(GL_MODELVIEW);`
183	`glLoadIdentity();`	186	`glLoadIdentity();`
184	`Vec3f eye;`	187	`Vec3f eye;`
185	`Vec3f _centre;`	188	`Vec3f _centre;`
186	`Vec3f up;`	189	`Vec3f up;`
187	`get_view_param(eye, _centre, up);`	190	`get_view_param(eye, _centre, up);`
188	`gluLookAt(eye[0], eye[1], eye[2],`	191	`gluLookAt(eye[0], eye[1], eye[2],`
189	`_centre[0], _centre[1], _centre[2],`	192	`_centre[0], _centre[1], _centre[2],`
190	`up[0],up[1],up[2]);`	193	`up[0],up[1],up[2]);`
191	`}`	194	`}`
192		195
193	`bool QuatTrackBall::is_spinning() const`	196	`bool QuatTrackBall::is_spinning() const`
194	`{`	197	`{`
195	`static const Quatf null_quat(0,0,0,1);`	198	`static const Quatf null_quat(0,0,0,1);`
196	`if(!(qinc == null_quat))`	199	`if(!(qinc == null_quat))`
197	`return true;`	200	`return true;`
198	`return false;`	201	`return false;`
199	`}`	202	`}`
200	`}`	203	`}`
201		204

Subversion Repositories gelsvn

(root)/trunk/src/GLGraphics/QuatTrackBall.cpp – Rev 601 → 609