Customized select()
function that enables the selection of several objects.
Object selection is preformed using the left mouse button. Press Shift to add objects to the selection, and Alt to remove objects from the selection.
Individual objects (click on them) as well as rectangular regions (click and drag mouse) can be
selected. To do this, the selection region size is modified and the endSelection()
function has been overloaded so that all the objects of the region are taken into account
(the default implementation only selects the closest object).
The selected objects can then be manipulated by pressing the Control key. Other set operations (parameter edition, deletion...) can also easily be applied to the selected objects.
#include "QGLViewer/qglviewer.h" #include "object.h" #if QT_VERSION < 0x040000 # include "qptrvector.h" #endif class Viewer : public QGLViewer { public: Viewer(); protected : virtual void draw(); virtual void init(); virtual QString helpString() const; // Selection functions virtual void drawWithNames(); virtual void endSelection(const QPoint&); // Mouse events functions virtual void mousePressEvent(QMouseEvent *e); virtual void mouseMoveEvent(QMouseEvent *e); virtual void mouseReleaseEvent(QMouseEvent *e); private : void startManipulation(); void drawSelectionRectangle() const; void addIdToSelection(int id); void removeIdFromSelection(int id); // Current rectangular selection QRect rectangle_; // Different selection modes enum SelectionMode { NONE, ADD, REMOVE }; SelectionMode selectionMode_; #if QT_VERSION < 0x040000 // Objects of the scene QPtrVector<Object> objects_; // ids of the selected objects QValueList<int> selection_; #else QList<Object*> objects_; QList<int> selection_; #endif };
#include "multiSelect.h" #include "manipulatedFrameSetConstraint.h" #if QT_VERSION >= 0x040000 # include <QMouseEvent> #endif using namespace qglviewer; Viewer::Viewer() { selectionMode_ = NONE; // Fill the scene with objects positionned on a regular grid. // Consider increasing selectBufferSize() if you use more objects. const int nb = 10; for (int i=-nb; i<=nb; ++i) for (int j=-nb; j<=nb; ++j) { Object* o = new Object(); o->frame.setPosition(Vec(i/float(nb), j/float(nb), 0.0)); #if QT_VERSION < 0x040000 // How could they sell this ? objects_.resize(objects_.size()+1); objects_.insert(objects_.size()-1, o); #else objects_.append(o); #endif } } void Viewer::init() { // A ManipulatedFrameSetConstraint will apply displacements to the selection setManipulatedFrame(new ManipulatedFrame()); manipulatedFrame()->setConstraint(new ManipulatedFrameSetConstraint()); // Used to display semi-transparent relection rectangle glBlendFunc(GL_ONE, GL_ONE); restoreStateFromFile(); help(); } QString Viewer::helpString() const { QString text("<h2>m u l t i S e l e c t </h2>"); text += "This example illustrates an application of the <code>select()</code> function that "; text += "enables the selection of several objects.<br><br>"; text += "Object selection is preformed using the left mouse button. Press <b>Shift</b> to add objects "; text += "to the selection, and <b>Alt</b> to remove objects from the selection.<br><br>"; text += "Individual objects (click on them) as well as rectangular regions (click and drag mouse) can be selected. "; text += "To do this, the selection region size is modified and the <code>endSelection()</code> function "; text += "has been overloaded so that <i>all</i> the objects of the region are taken into account "; text += "(the default implementation only selects the closest object).<br><br>"; text += "The selected objects can then be manipulated by pressing the <b>Control</b> key. "; text += "Other set operations (parameter edition, deletion...) can also easily be applied to the selected objects."; return text; } // D r a w i n g f u n c t i o n void Viewer::draw() { // Draws selected objects only. glColor3f(0.9f, 0.3f, 0.3f); #if QT_VERSION < 0x040000 for (QValueList<int>::const_iterator it=selection_.begin(), end=selection_.end(); it != end; ++it) #else for (QList<int>::const_iterator it=selection_.begin(), end=selection_.end(); it != end; ++it) #endif objects_.at(*it)->draw(); // Draws all the objects. Selected ones are not repainted because of GL depth test. glColor3f(0.8f, 0.8f, 0.8f); for (int i=0; i<int(objects_.size()); i++) objects_.at(i)->draw(); // Draws manipulatedFrame (the set's rotation center) if (manipulatedFrame()->isManipulated()) { glPushMatrix(); glMultMatrixd(manipulatedFrame()->matrix()); drawAxis(0.5); glPopMatrix(); } // Draws rectangular selection area. Could be done in postDraw() instead. if (selectionMode_ != NONE) drawSelectionRectangle(); } // C u s t o m i z e d m o u s e e v e n t s void Viewer::mousePressEvent(QMouseEvent* e) { // Start selection. Mode is ADD with Shift key and TOGGLE with Alt key. rectangle_ = QRect(e->pos(), e->pos()); #if QT_VERSION < 0x040000 if ((e->button() == Qt::LeftButton) && (e->state() == Qt::ShiftButton)) selectionMode_ = ADD; else if ((e->button() == Qt::LeftButton) && (e->state() == Qt::AltButton)) selectionMode_ = REMOVE; else { if (e->state() == Qt::ControlButton) #else if ((e->button() == Qt::LeftButton) && (e->modifiers() == Qt::ShiftModifier)) selectionMode_ = ADD; else if ((e->button() == Qt::LeftButton) && (e->modifiers() == Qt::AltModifier)) selectionMode_ = REMOVE; else { if (e->modifiers() == Qt::ControlModifier) #endif startManipulation(); QGLViewer::mousePressEvent(e); } } void Viewer::mouseMoveEvent(QMouseEvent* e) { if (selectionMode_ != NONE) { // Updates rectangle_ coordinates and redraws rectangle #if QT_VERSION < 0x030000 rectangle_.setX(e->x()); rectangle_.setY(e->y()); #else rectangle_.setBottomRight(e->pos()); #endif updateGL(); } else QGLViewer::mouseMoveEvent(e); } void Viewer::mouseReleaseEvent(QMouseEvent* e) { if (selectionMode_ != NONE) { // Actual selection on the rectangular area. // Possibly swap left/right and top/bottom to make rectangle_ valid. #if QT_VERSION < 0x040000 rectangle_ = rectangle_.normalize(); #else rectangle_ = rectangle_.normalized(); #endif // Define selection window dimensions setSelectRegionWidth(rectangle_.width()); setSelectRegionHeight(rectangle_.height()); // Compute rectangle center and perform selection select(rectangle_.center()); // Update display to show new selected objects updateGL(); } else QGLViewer::mouseReleaseEvent(e); } // C u s t o m i z e d s e l e c t i o n p r o c e s s void Viewer::drawWithNames() { for (int i=0; i<int(objects_.size()); i++) { glPushName(i); objects_.at(i)->draw(); glPopName(); } } void Viewer::endSelection(const QPoint&) { // Flush GL buffers glFlush(); // Get the number of objects that were seen through the pick matrix frustum. Reset GL_RENDER mode. GLint nbHits = glRenderMode(GL_RENDER); if (nbHits > 0) { // Interpret results : each object created 4 values in the selectBuffer(). // (selectBuffer())[4*i+3] is the id pushed on the stack. for (int i=0; i<nbHits; ++i) switch (selectionMode_) { case ADD : addIdToSelection((selectBuffer())[4*i+3]); break; case REMOVE : removeIdFromSelection((selectBuffer())[4*i+3]); break; default : break; } } selectionMode_ = NONE; } void Viewer::startManipulation() { Vec averagePosition; ManipulatedFrameSetConstraint* mfsc = (ManipulatedFrameSetConstraint*)(manipulatedFrame()->constraint()); mfsc->clearSet(); #if QT_VERSION < 0x040000 for (QValueList<int>::const_iterator it=selection_.begin(), end=selection_.end(); it != end; ++it) #else for (QList<int>::const_iterator it=selection_.begin(), end=selection_.end(); it != end; ++it) #endif { mfsc->addObjectToSet(objects_[*it]); averagePosition += objects_[*it]->frame.position(); } if (selection_.size() > 0) manipulatedFrame()->setPosition(averagePosition / selection_.size()); } // S e l e c t i o n t o o l s void Viewer::addIdToSelection(int id) { if (!selection_.contains(id)) selection_.push_back(id); } void Viewer::removeIdFromSelection(int id) { #if QT_VERSION < 0x040000 selection_.remove(id); #else selection_.removeAll(id); #endif } void Viewer::drawSelectionRectangle() const { startScreenCoordinatesSystem(); glDisable(GL_LIGHTING); glEnable(GL_BLEND); glColor4f(0.0, 0.0, 0.3f, 0.3f); glBegin(GL_QUADS); glVertex2i(rectangle_.left(), rectangle_.top()); glVertex2i(rectangle_.right(), rectangle_.top()); glVertex2i(rectangle_.right(), rectangle_.bottom()); glVertex2i(rectangle_.left(), rectangle_.bottom()); glEnd(); glLineWidth(2.0); glColor4f(0.4f, 0.4f, 0.5f, 0.5f); glBegin(GL_LINE_LOOP); glVertex2i(rectangle_.left(), rectangle_.top()); glVertex2i(rectangle_.right(), rectangle_.top()); glVertex2i(rectangle_.right(), rectangle_.bottom()); glVertex2i(rectangle_.left(), rectangle_.bottom()); glEnd(); glDisable(GL_BLEND); glEnable(GL_LIGHTING); stopScreenCoordinatesSystem(); }
#include "QGLViewer/constraint.h" #include "object.h" #if QT_VERSION < 0x040000 # include <qptrlist.h> #endif class ManipulatedFrameSetConstraint : public qglviewer::Constraint { public: void clearSet(); void addObjectToSet(Object* o); virtual void constrainTranslation(qglviewer::Vec &translation, qglviewer::Frame *const frame); virtual void constrainRotation(qglviewer::Quaternion &rotation, qglviewer::Frame *const frame); private : #if QT_VERSION < 0x040000 // Objects of the scene QPtrList<Object> objects_; #else QList<Object*> objects_; #endif };
#ifndef OBJECT_H_ #define OBJECT_H_ #include "QGLViewer/frame.h" class Object { public : void draw() const; qglviewer::Frame frame; }; #endif // OBJECT_H_
#include "multiSelect.h" #include <qapplication.h> int main(int argc, char** argv) { QApplication application(argc,argv); Viewer viewer; #if QT_VERSION < 0x040000 application.setMainWidget(&viewer); #else viewer.setWindowTitle("multiSelect"); #endif viewer.show(); return application.exec(); }
#include "manipulatedFrameSetConstraint.h" #include "QGLViewer/frame.h" using namespace qglviewer; void ManipulatedFrameSetConstraint::clearSet() { objects_.clear(); } void ManipulatedFrameSetConstraint::addObjectToSet(Object* o) { objects_.append(o); } void ManipulatedFrameSetConstraint::constrainTranslation(qglviewer::Vec &translation, Frame *const) { #if QT_VERSION < 0x040000 for (QPtrList<Object>::iterator it=objects_.begin(), end=objects_.end(); it != end; ++it) #else for (QList<Object*>::iterator it=objects_.begin(), end=objects_.end(); it != end; ++it) #endif (*it)->frame.translate(translation); } void ManipulatedFrameSetConstraint::constrainRotation(qglviewer::Quaternion &rotation, Frame *const frame) { // A little bit of math. Easy to understand, hard to guess (tm). // rotation is expressed in the frame local coordinates system. Convert it back to world coordinates. const Vec worldAxis = frame->inverseTransformOf(rotation.axis()); const Vec pos = frame->position(); const float angle = rotation.angle(); #if QT_VERSION < 0x040000 for (QPtrList<Object>::iterator it=objects_.begin(), end=objects_.end(); it != end; ++it) #else for (QList<Object*>::iterator it=objects_.begin(), end=objects_.end(); it != end; ++it) #endif { // Rotation has to be expressed in the object local coordinates system. Quaternion qObject((*it)->frame.transformOf(worldAxis), angle); (*it)->frame.rotate(qObject); // Comment these lines only rotate the objects Quaternion qWorld(worldAxis, angle); // Rotation around frame world position (pos) (*it)->frame.setPosition(pos + qWorld.rotate((*it)->frame.position() - pos)); } }
#include <qgl.h> #include "object.h" using namespace qglviewer; void Object::draw() const { static GLUquadric* quad = gluNewQuadric(); glPushMatrix(); glMultMatrixd(frame.matrix()); gluSphere(quad, 0.03, 10, 6); gluCylinder(quad, 0.03, 0.0, 0.09, 10, 1); glPopMatrix(); }
Back to the examples main page.