Heavily restructured. To be completed only rotation works...

wrap/gui/trackball.cpp

@@ -24,6 +24,9 @@
   History
 
 $Log: not supported by cvs2svn $
+Revision 1.7  2004/05/14 03:15:09  ponchio
+Redesigned partial version.
+
 Revision 1.6  2004/05/12 20:55:18  ponchio
 *** empty log message ***
 
@@ -41,7 +44,7 @@ Adding copyright.
 
 
 ****************************************************************************/
-
+#include<gl/glew.h>
 #include "trackball.h"
 
 #include <wrap/gl/math.h>
@@ -111,7 +114,15 @@ void Trackball::GetView() {
 }
 
 void Trackball::Apply() { 
+  glTranslate(center);
   glMultMatrix(track.Matrix());
+  glTranslate(-center);
+}
+
+void Trackball::ApplyInverse() { 
+  glTranslate(center);
+  glMultMatrix(track.InverseMatrix());
+  glTranslate(-center);
 }
 
 /***************************************************************/
@@ -163,6 +174,15 @@ void Trackball::DrawPlaneHandle() {
 }
 
 void Trackball::Draw() {
+  
+  glPushMatrix();
+  ApplyInverse();
+  glBegin(GL_POINTS);
+    for(int i=0;i<Hits.size();++i)
+    glVertex(Hits[i]);
+  glEnd();
+  glPopMatrix();
+
   glPushMatrix();
   
   glTranslate(center);
@@ -183,17 +203,15 @@ void Trackball::Draw() {
   glMaterialfv(GL_FRONT_AND_BACK,GL_EMISSION,amb);
   glMaterialfv(GL_FRONT_AND_BACK,GL_DIFFUSE,col);
   glPushMatrix();
+    DrawCircle();
+    glPushMatrix();
   
-  DrawCircle();
+      glRotatef(90,1,0,0);
-  glPushMatrix();
+      DrawCircle();
-  
+      glRotatef(90,0,1,0);
-  glRotatef(90,1,0,0);
+      DrawCircle();
-  DrawCircle();
+      
-  glRotatef(90,0,1,0);
+    glPopMatrix();
-  DrawCircle();
-  
-  glPopMatrix();
-  
   glPopMatrix();
 		
   glColor4f(1.0,.8f,.8f,1.0f);
@@ -249,10 +267,11 @@ void Trackball::Reset() {
 }
 
 //interface
-void Trackball::MouseDown(int x, int y, Trackball::Button button) {
+void Trackball::MouseDown(int x, int y, int button) {
   current_button |= button;  
   SetCurrentAction();
   last_point = Point3f((float)x, (float)y, 0);
+  Hits.clear();
 }
 
 void Trackball::MouseMove(int x, int y) {  
@@ -264,7 +283,7 @@ void Trackball::MouseMove(int x, int y) {
   current_mode->Apply(this, Point3f(float(x), float(y), 0));
 } 
 
-void Trackball::MouseUp(int /* x */, int /* y */, Trackball::Button button) { 
+void Trackball::MouseUp(int /* x */, int /* y */, int button) { 
   current_button &= (~button);
   SetCurrentAction();
 } 

wrap/gui/trackball.h

@@ -25,6 +25,9 @@
   History
 
 $Log: not supported by cvs2svn $
+Revision 1.6  2004/05/14 03:15:09  ponchio
+Redesigned partial version.
+
 Revision 1.5  2004/05/12 20:55:18  ponchio
 *** empty log message ***
 
@@ -47,17 +50,13 @@ Adding copyright.
 #include <wrap/gui/view.h>
 #include <wrap/gui/trackmode.h>
 #include <list>
+#include <vector>
 #include <map>
 
 namespace vcg {
-  /* A trackball stores two transformations
+  /* A trackball stores a transformation called 'track' that effectively rotate the object.
-     the first one, local, is the one 'placing' the trackball somewhere, 
+     the rotation center, and size are kept in center and radius.
-     the second one, track, is the one that effectively rotate the object.
+   
-
-     The 'local' transformation is the one that contains information about
-     the rotation center, the size and the orientation of the trackball.
-     the 'track' is the one implementing the effective transformation.
-
   */
 
   class Transform {
@@ -97,6 +96,7 @@ namespace vcg {
     //operating
     void GetView();
     void Apply();
+    void ApplyInverse();
     void Draw();
     void ApplynDraw() { Apply(); Draw(); }
     void Reset();
@@ -107,9 +107,9 @@ namespace vcg {
     static void DrawPlaneHandle();
 
     //interface
-    void MouseDown(int x, int y, Button button);
+    void MouseDown(int x, int y, /*Button*/ int button);
     void MouseMove(int x, int y); 
-    void MouseUp(int x, int y, Button button); 
+    void MouseUp(int x, int y, /*Button */ int button); 
     void MouseWheel(Button notch);
     void ButtonUp(Button button);
     void ButtonDown(Button button);
@@ -147,15 +147,9 @@ namespace vcg {
     };
 
 	
-    ///Find the current action ussing the current button
-
-
     //protected:
     View<float> camera;
 
-    /*    float ScreenRadius;
-	  Point3f ScreenCenter;*/
-
     void SetCurrentAction();
   
     int current_button;
@@ -166,6 +160,7 @@ namespace vcg {
     Similarityf last_track;
     Similarityf last_view;
     Point3f last_point;
+    std::vector<Point3f> Hits;
     bool dragging;
     int button_mask;
 
@@ -176,14 +171,6 @@ namespace vcg {
     std::list<Transform> history;
     int history_size;
 
-    //Point3f ScreenOrigin();      //center of trackball in Screen coord   
-    //Point3f ModelOrigin();       //center of trackball in Model coord
-  
-    //    Matrix44f ScreenToModel();  //forse non serve.....
-    //    Similarityf ModelToLocal();
-  
-    //Point3f ScreenToLocal(const Point3f &p);
-    //Point3f LocalToScreen(const Point3f &p);  
     friend class TrackMode;
   };
 

wrap/gui/trackmode.cpp

@@ -24,6 +24,9 @@
   History
 
 $Log: not supported by cvs2svn $
+Revision 1.5  2004/05/14 03:15:09  ponchio
+Redesigned partial version.
+
 Revision 1.4  2004/05/07 12:46:08  cignoni
 Restructured and adapted in a better way to opengl
 
@@ -45,15 +48,20 @@ Adding copyright.
 using namespace std;
 
 using namespace vcg;
-
+/// Compute the plane plane perpedicular to view dir and passing through manip center
-Plane3f TrackMode::GetViewPlane(const View<float> &camera, Point3f center) {
+Plane3f TrackMode::GetViewPlane(const View<float> &camera, const Point3f &center) {
   Point3f vp = camera.ViewPoint();
   
-  Plane3f pl; //plane perpedicular to view dir and passing through manip center
+  Plane3f pl; 
-  pl.Set(vp - center, (vp - center)*center);
+  Point3f plnorm= vp - center;
+  plnorm.Normalize();
+  pl.Set(plnorm, plnorm*center);
   return pl;
 }
 
+/// Given a point p in window coordinate it compute the point where the lie p 
+/// over the plane paralell the viewplane and passing through the center of the trackball
+
 Point3f TrackMode::HitViewPlane(Trackball *tb, const Point3f &p) {
   // plane perpedicular to view direction and passing through manip center
   Plane3f vp = GetViewPlane(tb->camera, tb->center); 
@@ -65,14 +73,23 @@ Point3f TrackMode::HitViewPlane(Trackball *tb, const Point3f &p) {
   return PonVP;
 }
 
-
+// the most important function; given a new point in window coord, it update the transformation computed by the trackball.
+// General scheme : the transformation is a function of just the begin and current mouse positions, with greater precision is function of just two 3d points over the manipulator.
 void SphereMode::Apply(Trackball *tb, Point3f new_point) {
   Point3f hitOld=Hit(tb, tb->last_point);
   Point3f hitNew=Hit(tb, new_point);
+  tb->Hits.push_back(hitNew);
+
+  Point3f axis = (hitNew- tb->center)^(hitOld- tb->center); 
+
+  //  Figure out how much to rotate around that axis.
+  //float phi=Angle((hitNew- tb->center),(hitOld- tb->center));
+  float phi = Distance(hitNew,hitOld) / tb->radius;
+    
+  tb->track.rot = tb->last_track.rot * Quaternionf(phi,axis);
+ /* Codice Originale Ponchio 
 
   Point3f ref = (tb->camera.ViewPoint() - tb->center).Normalize();
-
-
   Point3f axis = hitNew^ref; 
   axis.Normalize();
   float dist = (hitNew - ref).Norm()/2;
@@ -88,9 +105,65 @@ void SphereMode::Apply(Trackball *tb, Point3f new_point) {
   Quaternionf diff = r * Quaternionf(phi, axis) * 
                      Quaternionf(-ophi, oaxis) * Inverse(r);
 
-  tb->track = Similarityf().SetRotate(diff) * tb->last_track;
+  tb->track = Similarityf().SetRotate(diff) * tb->last_track;*/
+
 }
 
+/*
+dato un punto in coordinate di schermo e.g. in pixel stile opengl 
+calcola il punto di intersezione tra la viewline  che passa per viewpoint e per hitplane e l'iperboloide.
+l'iperboloide si assume essere quello di rotazione attorno alla retta viewpoint-center e di raggio rad
+si assume come sistema di riferimento quello con l'origine su center ecome x la retta center-viewpoint
+
+eq linea
+       hitplane.y
+y = - ----------- * x + hitplane.y 
+      viewpoint.x
+
+eq hiperboloide di raggio r (e.g. che passa per (r/sqrt2,r/sqrt2) 
+
+     1
+y = --- * (r^2 /2.0)
+     x 
+
+ hitplane.y
+ ----------- * x^2 - hitplane.y *x + (r^2/2.0) == 0
+ viewpoint.x
+
+*/
+bool SphereMode::HitHyper(Point3f center,  float radius, Point3f viewpoint, Plane3f vp, Point3f hitplane, Point3f &hit) 
+{
+  float hitplaney = Distance(center,hitplane);
+  float viewpointx= Distance(center,viewpoint);
+
+  float a =  hitplaney/viewpointx;
+  float b = -hitplaney;
+  float c = radius*radius/2.0f;
+  float delta = b*b - 4*a*c;
+  float x1,x2,xval,yval;
+  if(delta>0)
+  {
+    x1= (- b - sqrt(delta))/(2.0*a);
+    x2= (- b + sqrt(delta))/(2.0*a);
+    
+    xval=x1; // always take the minimum value solution
+    yval=c/xval;     //  alternatively it also oould be the other part of the equation yval=-(hitplaney/viewpointx)*xval+hitplaney;
+  }
+  else 
+  {
+    return false;
+  }
+  // Computing the result in 3d space;
+  Point3f dirRadial=hitplane-center;
+  dirRadial.Normalize();
+  Point3f dirView=vp.Direction();
+  dirView.Normalize();
+  hit= center +dirRadial*yval+dirView*xval;
+  return true;
+}
+
+
+
 /* dato un punto in coordinate di schermo e.g. in pixel stile opengl 
    restituisce un punto in coordinate di mondo sulla superficie 
    della trackball.
@@ -101,45 +174,76 @@ void SphereMode::Apply(Trackball *tb, Point3f new_point) {
 
                                        X   0   sqrt(1/2)  1  
    eq sfera:              y=sqrt(1-x*x);   1   sqrt(1/2)  0   
-   eq iperboloide :       y=1/2x;         inf  sqrt(1/2)  1/2
+   eq iperboloide :       y=1/2*x;         inf  sqrt(1/2)  1/2
    eq cono                y=x+sqrt(2);
 
    */
 
 Point3f SphereMode::Hit(Trackball *tb, const Point3f &p) {
   const float Thr = tb->radius/math::Sqrt(2.0f);
+
   Line3fN vn = tb->camera.ViewLineFromModel(tb->center);
   Line3fN ln = tb->camera.ViewLineFromWindow(Point3f(p[0],p[1],0));
   Point3f viewpoint = tb->camera.ViewPoint();
-
   Plane3f vp = GetViewPlane(tb->camera, tb->center); 
-  vp.SetOffset(vp.Offset() + Thr);
+  Point3f hit,hitPlane,hitSphere,hitSphere1,hitSphere2,hitHyper;
+  Intersection<float>(vp, ln, hitPlane);
+  Sphere3f sphere(tb->center,tb->radius);
+  bool resSp = Intersection<float>(sphere, ln, hitSphere1, hitSphere2);
+  if(Distance(viewpoint,hitSphere1)<Distance(viewpoint,hitSphere2)) 
+        hitSphere=hitSphere1;
+  else  hitSphere=hitSphere2;
 
-  Point3f hit;
+  float dl=Distance(ln,tb->center);
-  bool res = Intersection<float>(vp, ln, hit);
+  bool resHp = HitHyper(tb->center, tb->radius, viewpoint, vp, hitPlane, hitHyper) ;
-  float d = Distance(tb->center - vn.Direction()*Thr, hit);
-  if(d < Thr) {
-    Point3f hit2;
-    Sphere3f sphere(tb->center, tb->radius);
-    bool res = Intersection<float>(sphere, ln, hit, hit2);
 
-    //find closest intersection to sphere
+  // four cases 
-    float d = (hit - viewpoint).Norm();
+  
-    float d2 = (hit2 - viewpoint).Norm();
+  // 1) Degenerate line tangent to both sphere and hyperboloid! 
-    if(d > d2) hit = hit2;
+  if((!resSp && !resHp) )
-    hit -= tb->center;
+  {
-  } else {
+    hit=ClosestPoint(ln,tb->center);
-    if(d > 2.99 * Thr) 
+    //printf("closest point to line %f\n",Distance(hit,tb->center));
-      d = 2.99 * Thr;
+    return hit;
-    Point3f norm = (hit - tb->center)^(viewpoint - tb->center);
-    norm.Normalize();
-    float phi = -M_PI/4 - 3*M_PI/8 *(d - Thr)/Thr;
-
-    Quaternionf q(phi, norm);
-    hit = q.Rotate((viewpoint - tb->center).Normalize() * tb->radius);
   }
-  hit.Normalize();
+  if((resSp && !resHp) ) return hitSphere; // 2) line cross only the sphere
-  return hit;
+  if((!resSp && resHp) ) return hitHyper;  // 3) line cross only the hyperboloid
+
+  // 4) line cross both sphere and hyperboloid: choose according angle.
+  float angleDeg=math::ToDeg(Angle((viewpoint-tb->center),(hitSphere-tb->center)));
+  //printf("Angle %f (%5.2f %5.2f %5.2f) (%5.2f %5.2f %5.2f)\n",angleDeg,hitSphere[0],hitSphere[1],hitSphere[2],hitHyper[0],hitHyper[1],hitHyper[2]);
+  if(angleDeg<45) return hitSphere;
+          else    return hitHyper;
+
+  // 
+  // Codice ORIGINALE PONCHIO
+  //vp.SetOffset(vp.Offset() + Thr);
+
+  //Point3f hit;
+  //bool res = Intersection<float>(vp, ln, hit);
+  //float d = Distance(tb->center - vn.Direction()*Thr, hit);
+  //if(d < Thr) {
+  //  Point3f hit2;
+  //  Sphere3f sphere(tb->center, tb->radius);
+  //  bool res = Intersection<float>(sphere, ln, hit, hit2);
+
+  //  //find closest intersection to sphere
+  //  float d = (hit - viewpoint).Norm();
+  //  float d2 = (hit2 - viewpoint).Norm();
+  //  if(d > d2) hit = hit2;
+  //  hit -= tb->center;
+  //} else {
+  //  if(d > 2.99 * Thr) 
+  //    d = 2.99 * Thr;
+  //  Point3f norm = (hit - tb->center)^(viewpoint - tb->center);
+  //  norm.Normalize();
+  //  float phi = -M_PI/4 - 3*M_PI/8 *(d - Thr)/Thr;
+
+  //  Quaternionf q(phi, norm);
+  //  hit = q.Rotate((viewpoint - tb->center).Normalize() * tb->radius);
+  //}
+  // hit.Normalize();
+  // return hit;
 }
 
 void PlaneMode::Apply(Trackball *tb, Point3f new_point) {

wrap/gui/trackmode.h

@@ -24,6 +24,9 @@
   History
 
 $Log: not supported by cvs2svn $
+Revision 1.5  2004/05/14 03:15:09  ponchio
+Redesigned partial version.
+
 Revision 1.4  2004/05/07 12:46:08  cignoni
 Restructured and adapted in a better way to opengl
 
@@ -52,12 +55,8 @@ public:
   virtual ~TrackMode() {}
   virtual void Apply(Trackball *trackball, Point3f new_point) = 0;
   virtual void Draw() {}
-  //virtual void Draw() {}
-  //  virtual Similarityf ComputeFromWindow(const Point3f &old_point, 
-  //const Point3f &new_point) = 0;
-  //  Point3f Hit(const Point3f &p);
  protected:
-  Plane3f GetViewPlane(const View<float> &view, Point3f center);
+  Plane3f GetViewPlane(const View<float> &view, const Point3f &center);
   Point3f HitViewPlane(Trackball *trackball, const Point3f &p);
 };
  
@@ -68,12 +67,14 @@ class SphereMode: public TrackMode {
   void Apply(Trackball *trackball, Point3f new_point);
  protected:
   Point3f Hit(Trackball *trackball, const Point3f &p);
+  bool HitHyper(Point3f center,  float radius, Point3f viewpoint, Plane3f vp, Point3f hitplane, Point3f &hit) ;
+
 };
 
 class CylinderMode: public TrackMode {
 public:
-  CylinderMode(const Line3f &line, float radius = 1) {}
+  CylinderMode(const Line3f &/*line*/, float /*radius = 1*/) {}
-  void Apply(Trackball *trackball, Point3f new_point) {}
+  void Apply(Trackball * /*trackball*/, Point3f /*new_point*/) {}
 protected:
   Line3f line;
   float radius;
@@ -89,15 +90,15 @@ protected:
 
 class LineMode: public TrackMode {
 public:
-  LineMode(const Line3f &line) {}
+  LineMode(const Line3f &/*line*/) {}
-  void Apply(Trackball *trackball, Point3f new_point) {}
+  void Apply(Trackball * /*trackball*/, Point3f /*new_point*/) {}
 protected:
   Line3f line;
 };
 
 class ScaleMode: public TrackMode {
 public:
-  void Apply(Trackball *trackball, Point3f new_point) {}
+  void Apply(Trackball * /*trackball*/, Point3f /*new_point*/) {}
 };
 
 }//namespace