/*
* Ok, simulate a track-ball. Project the points onto the virtual
* trackball, then figure out the axis of rotation, which is the cross
* product of P1 P2 and O P1 (O is the center of the ball, 0,0,0)
* Note: This is a deformed trackball-- is a trackball in the center,
* but is deformed into a hyperbolic sheet of rotation away from the
* center. This particular function was chosen after trying out
* several variations.
*
* It is assumed that the arguments to this routine are in the range
* (-1.0 ... 1.0)
*/
static void
trackball ( float q[4], float p1x, float p1y, float p2x, float p2y )
{
float a[3]; /* Axis of rotation */
float phi; /* how much to rotate about axis */
float p1[3], p2[3], d[3];
float t;
if (p1x == p2x && p1y == p2y)
{
// Zero rotation
vzero(q);
q[3] = 1.0;
return;
}
// First, figure out z-coordinates for projection of P1 and P2 to
// deformed sphere
vset(p1,p1x,p1y,tb_project_to_sphere(TRACKBALLSIZE,p1x,p1y));
vset(p2,p2x,p2y,tb_project_to_sphere(TRACKBALLSIZE,p2x,p2y));
// Now, we want the cross product of P1 and P2
vcross(p2,p1,a);
// Figure out how much to rotate around that axis.
vsub(p1,p2,d);
t = vlength(d) / (2.0*TRACKBALLSIZE);
// Avoid problems with out-of-control values...
if (t > 1.0) t = 1.0;
if (t < -1.0) t = -1.0;
phi = 2.0 * asin(t);
axis_to_quat(a,phi,q);
}
/*
* Ok, simulate a track-ball. Project the points onto the virtual
* trackball, then figure out the axis of rotation, which is the cross
* product of P1 P2 and O P1 (O is the center of the ball, 0,0,0)
* Note: This is a deformed trackball-- is a trackball in the center,
* but is deformed into a hyperbolic sheet of rotation away from the
* center. This particular function was chosen after trying out
* several variations.
*
* It is assumed that the arguments to this routine are in the range
* (-1.0 ... 1.0)
*/
void trackball( double q[4], double p1x, double p1y, double p2x, double p2y )
{
double a[3]; /* Axis of rotation */
double phi; /* how much to rotate about axis */
double p1[3], p2[3], d[3];
double t;
if( p1x == p2x && p1y == p2y )
{
/* Zero rotation */
vzero( q );
q[3] = 1.0;
return;
}
/*
* First, figure out z-coordinates for projection of P1 and P2 to
* deformed sphere
*/
vset( p1, p1x, p1y, tb_project_to_sphere( TRACKBALLSIZE, p1x, p1y ) );
vset( p2, p2x, p2y, tb_project_to_sphere( TRACKBALLSIZE, p2x, p2y ) );
/*
* Now, we want the cross product of P1 and P2
*/
vcross(p2,p1,a);
/*
* Figure out how much to rotate around that axis.
*/
vsub( p1, p2, d );
t = vlength( d ) / (2.0f * TRACKBALLSIZE);
/*
* Avoid problems with out-of-control values...
*/
if( t > 1.0 )
t = 1.0;
if( t < -1.0 )
t = -1.0;
phi = 2.0f * (double) asin( t );
axis_to_quat( a, phi, q );
}
/*
* Ok, simulate a track-ball. Project the points onto the virtual
* trackball, then figure out the axis of rotation, which is the cross
* product of P1 P2 and O P1 (O is the center of the ball, 0,0,0)
* Note: This is a deformed trackball-- is a trackball in the center,
* but is deformed into a hyperbolic sheet of rotation away from the
* center. This particular function was chosen after trying out
* several variations.
*
* It is assumed that the arguments to this routine are in the range
* (-1.0 ... 1.0)
*/
void CameraManipulator::trackball(osg::Vec3& axis,float& angle, float p1x, float p1y, float p2x, float p2y)
{
/*
* First, figure out z-coordinates for projection of P1 and P2 to
* deformed sphere
*/
osg::Matrix rotation_matrix(_rotation);
osg::Vec3 uv = osg::Vec3(0.0f,1.0f,0.0f)*rotation_matrix;
osg::Vec3 sv = osg::Vec3(1.0f,0.0f,0.0f)*rotation_matrix;
osg::Vec3 lv = osg::Vec3(0.0f,0.0f,-1.0f)*rotation_matrix;
osg::Vec3 p1 = sv * p1x + uv * p1y - lv * tb_project_to_sphere(_trackballSize, p1x, p1y);
osg::Vec3 p2 = sv * p2x + uv * p2y - lv * tb_project_to_sphere(_trackballSize, p2x, p2y);
/*
* Now, we want the cross product of P1 and P2
*/
// Robert,
//
// This was the quick 'n' dirty fix to get the trackball doing the right
// thing after fixing the Quat rotations to be right-handed. You may want
// to do something more elegant.
// axis = p1^p2;
axis = p2^p1;
axis.normalize();
/*
* Figure out how much to rotate around that axis.
*/
float t = (p2 - p1).length() / (2.0 * _trackballSize);
/*
* Avoid problems with out-of-control values...
*/
if (t > 1.0) t = 1.0;
if (t < -1.0) t = -1.0;
angle = osg::inRadians(asin(t));
}
/*
* Ok, simulate a track-ball. Project the points onto the virtual
* trackball, then figure out the axis of rotation, which is the cross
* product of P1 P2 and O P1 (O is the center of the ball, 0,0,0)
* Note: This is a deformed trackball-- is a trackball in the center,
* but is deformed into a hyperbolic sheet of rotation away from the
* center. This particular function was chosen after trying out
* several variations.
*
* It is assumed that the arguments to this routine are in the range
* (-1.0 ... 1.0)
*/
quat & trackball(quat& q, vec2& pt1, vec2& pt2, nv_scalar trackballsize)
{
vec3 a; // Axis of rotation
nv_scalar phi; // how much to rotate about axis
vec3 d;
nv_scalar t;
if (pt1.x == pt2.x && pt1.y == pt2.y)
{
// Zero rotation
q = quat_id;
return q;
}
// First, figure out z-coordinates for projection of P1 and P2 to
// deformed sphere
vec3 p1(pt1.x,pt1.y,tb_project_to_sphere(trackballsize,pt1.x,pt1.y));
vec3 p2(pt2.x,pt2.y,tb_project_to_sphere(trackballsize,pt2.x,pt2.y));
// Now, we want the cross product of P1 and P2
cross(a,p1,p2);
// Figure out how much to rotate around that axis.
d.x = p1.x - p2.x;
d.y = p1.y - p2.y;
d.z = p1.z - p2.z;
t = _sqrt(d.x * d.x + d.y * d.y + d.z * d.z) / (trackballsize);
// Avoid problems with out-of-control values...
if (t > nv_one)
t = nv_one;
if (t < -nv_one)
t = -nv_one;
phi = nv_two * nv_scalar(asin(t));
axis_to_quat(q,a,phi);
return q;
}
void Manipulator::calcRotationArgs(osg::Vec3d& axis, float& angle,
float p1x, float p1y,float p2x, float p2y) {
osg::Matrixd rotation_matrix(_rotation);
osg::Vec3d uv = osg::Vec3d(0.0f,1.0f,0.0f)*rotation_matrix;
osg::Vec3d sv = osg::Vec3d(1.0f,0.0f,0.0f)*rotation_matrix;
osg::Vec3d lv = osg::Vec3d(0.0f,0.0f,-1.0f)*rotation_matrix;
osg::Vec3d p1 = sv * p1x + uv * p1y - lv * tb_project_to_sphere(_trackball_size, p1x, p1y);
osg::Vec3d p2 = sv * p2x + uv * p2y - lv * tb_project_to_sphere(_trackball_size, p2x, p2y);
axis = p2^p1;
axis.normalize();
float t = (p2 - p1).length() / (2.0 * _trackball_size);
if (t > 1.0) t = 1.0;
if (t < -1.0) t = -1.0;
angle = osg::inRadians(asin(t));
//2014/4/28
//2014/10/26,0.1
angle = 0.02 * angle;
}
/* Ok, simulate a track-ball. Project the points onto the virtual
* trackball, then figure out the axis of rotation, which is the cross
* product of P1 P2 and O P1 (O is the center of the ball, 0,0,0)
* Note: This is a deformed trackball-- is a trackball in the center,
* but is deformed into a hyperbolic sheet of rotation away from the
* center. This particular function was chosen after trying out
* several variations.
*
* It is assumed that the arguments to this routine are in the range
* (-1.0 ... 1.0)
*/
void trackball(double q[4], double p1x, double p1y, double p2x, double p2y){
double axis[3]; /* Axis of rotation */
double phi; /* how much to rotate about axis */
double p1[3], p2[3], d[3];
double t;
/* if zero rotation */
if(p1x == p2x && p1y == p2y){
vset(q, 0.0, 0.0, 0.0);
q[3] = 1.0;
return;
}
/* First, figure out z-coordinates for projection of P1 and P2 to */
/* the deformed sphere */
p1[0] = p1x;
p1[1] = p1y;
p1[2] = tb_project_to_sphere(TRACKBALLSIZE, p1x, p1y);
p2[0] = p2x;
p2[1] = p2y;
p2[2] = tb_project_to_sphere(TRACKBALLSIZE, p2x, p2y);
/* Now, we want the cross product of P1 and P2 */
vcross(axis, p2, p1);
/* Figure out how much to rotate around that axis. */
vsub(d, p1, p2);
t = vlength(d)/(2.0*TRACKBALLSIZE);
/* Avoid problems with out-of-control values. */
if(t > 1.0){ t = 1.0; }
if(t < -1.0){ t = -1.0; }
phi = 2.0 * asin(t);
axis_to_quat(axis, phi, q);
}
/*
* Ok, simulate a track-ball. Project the points onto the virtual
* trackball, then figure out the axis of rotation, which is the cross
* product of P1 P2 and O P1 (O is the center of the ball, 0,0,0)
* Note: This is a deformed trackball-- is a trackball in the center,
* but is deformed into a hyperbolic sheet of rotation away from the
* center. This particular function was chosen after trying out
* several variations.
*
* It is assumed that the arguments to this routine are in the range
* (-1.0 ... 1.0)
*/
void trackball(float q[4], float p1x, float p1y, float p2x, float p2y, float tbSize)
{
float a[3]; // Axis of rotation
float phi; // how much to rotate about axis
float p1[3], p2[3], d[3];
float t;
if( p1x == p2x && p1y == p2y ) {
/* Zero rotation */
vzero(q);
q[3] = 1.0;
return;
}
// First, figure out z-coordinates for projection of P1 and P2 to deformed sphere
vset( p1, p1x, p1y, tb_project_to_sphere(tbSize, p1x, p1y) );
vset( p2, p2x, p2y, tb_project_to_sphere(tbSize, p2x, p2y) );
// Now, we want the cross product of P1 and P2
vcross( p2, p1, a);
// Figure out how much to rotate around that axis
vsub( p1, p2, d);
t = vlength(d) / ( 2.0f * tbSize );
// Avoid problems with out-of-control values
if (t > 1.0) {
t = 1.0;
}
if (t < -1.0) {
t = -1.0;
}
phi = 2.0f * (float)asin(t);
axis_to_quat( a, phi, q );
}
