Hi, I am using the Drag handlers with an autotransform on them (see code below). I have it set to AutoscaleToScreen. This works great as long as I only have 1 view of the scene. When I have multiple views though, I get a problem where zooming in on one will cause the autotransform to change the scale of the dragger. I can click on the dragger just fine in that window, but when I go back to the other window and try and click on the dragger it is no longer scaled correctly. As an example, if I zoom in to view A then the translate drag handler become larger. I can click anywhere on them and they work correctly. When I go to View B that is zoomed out then I can click not only on the visual representation of the drag handler, but on a projection of it that extends past the visual end of the axis. If I do this the opposite way (Zoom out A and look at zoomed in B), then the opposite happens. I can only click on the drag handler on a smaller portion of the visible axis.
I looked around and found this post (http://forum.openscenegraph.org/viewtopic.php?t=4637&highlight=). > > The issue you are hitting up against is a limitation of > osg::AutoTransform in that it only has a single set of state so when > you have two or more views that require different stats you'll get > issues with both views attempting to sets it's value. The only way to > solve this would be to refactor osg::AutoTransform to have multiple > states in some way. > It looks like this may be related to this problem, but I am not sure. Does anyone have any experience with this issue? Is this issue caused by the state problem of autotransform? Has anyone else found a way around this problem? Does anyone have any suggestions for an easy way to get around this problem without redoing the autotransform node? Here is my drag handler code. Code: VsDragger::VsDragger(VsMovableItem *lpParent, BOOL bAllowTranslateX, BOOL bAllowTranslateY, BOOL bAllowTranslateZ, BOOL bAllowRotateX, BOOL bAllowRotateY, BOOL bAllowRotateZ) { if(!lpParent) THROW_ERROR(Al_Err_lParentNotDefined, Al_Err_strParentNotDefined); m_lpVsParent = lpParent; //Create the gripperMT and default it to loc=0, rot=0 m_osgGripperMT = new osg::MatrixTransform(); osg::Matrix osgMT; osgMT.makeIdentity(); m_osgGripperMT->setMatrix(osgMT); m_osgGripperMT->addChild(this); _autoTransform = new osg::AutoTransform; _autoTransform->setAutoScaleToScreen(true); addChild(_autoTransform.get()); _sizeTransform = new osg::MatrixTransform; // Screen coordinates because of AutoTransform parent _sizeTransform->setMatrix(osg::Matrix::scale(100, 100, 100)); _autoTransform->addChild(_sizeTransform.get()); _tbDragger = new VsTrackballDragger(bAllowRotateX, bAllowRotateY, bAllowRotateZ); _tbDragger->setName("TrackballDragger"); //addChild(_tbDragger.get()); _sizeTransform->addChild(_tbDragger.get()); _transDragger = new VsTranslateAxisDragger(bAllowTranslateX, bAllowTranslateY, bAllowTranslateZ); _transDragger->setName("TranslateAxisDragger"); //addChild(_transDragger.get()); _sizeTransform->addChild(_transDragger.get()); this->addDragger(_tbDragger.get()); this->addDragger(_transDragger.get()); this->getOrCreateStateSet()->setMode(GL_RESCALE_NORMAL, osg::StateAttribute::ON); this->setParentDragger(getParentDragger()); } VsDragger::~VsDragger(void) { } void VsDragger::setupDefaultGeometry() { _tbDragger->setupDefaultGeometry(); _transDragger->setupDefaultGeometry(); SetupMatrix(); } void VsDragger::AddToScene() { SetupMatrix(); if(m_lpVsParent && m_lpVsParent->RootGroup() && m_osgGripperMT.valid()) if(!m_lpVsParent->RootGroup()->containsNode(m_osgGripperMT.get())) m_lpVsParent->RootGroup()->addChild(m_osgGripperMT.get()); } void VsDragger::RemoveFromScene() { if(m_lpVsParent && m_lpVsParent->RootGroup() && m_osgGripperMT.valid()) if(m_lpVsParent->RootGroup()->containsNode(m_osgGripperMT.get())) m_lpVsParent->RootGroup()->removeChild(m_osgGripperMT.get()); } void VsDragger::SetupMatrix() { if(m_lpVsParent && m_lpVsParent->RootGroup() && m_osgGripperMT.valid()) { //This gives the radius of the boundign sphere for the selected part. //We will multiply that by 2 and then scale the entire dragger by that amount. //We will also use that setting for the minimum scale of the autotransform. float fltMaxDim = m_lpVsParent->Physics_GetBoundingRadius(); Simulator *lpSim = GetSimulator(); if(fltMaxDim > (lpSim->InverseDistanceUnits()/2.0f)) fltMaxDim = (lpSim->InverseDistanceUnits()/2.0f); //Use an equation to calculate the radius here. This seemed to work best. //I tried several size values and found a good radius scale that fit it. Then //I did a regression to find this equation of the line for the radius. float fltRadius = fltMaxDim*0.501794454f + 0.639290375f; //We are dividing the number by 100 because we are using a _sizeTransform that scales it up by 100. _autoTransform->setMinimumScale( (fltRadius*0.01f) ); //We use the final matrix here instead of local matrix because the joint can have an additional offset that //must be taken into account when setting up the dragger. m_osgGripperMT->setMatrix(m_lpVsParent->FinalMatrix()); //Set the matrix for the dragger back to default. osg::Matrix mtNull = osg::Matrix::identity(); mtNull *= osg::Matrix::scale(fltRadius,fltRadius,fltRadius); this->setMatrix(mtNull); //Lets setup the grip to zero out the rotation of the body so that it points //to the default axis of the parent it is connected to. osg::Matrix tempMT = m_lpVsParent->LocalMatrix(), invMT; tempMT.setTrans(osg::Vec3f(0, 0, 0)); invMT.invert(tempMT); //We want to scale the translate axis to be 1.5 times as big as the rotate axis dragger. // Scale the translate dragger up a bit, otherwise the axes // will be in the trackball dragger's sphere and we won't be // able to pick them. float axesScale = 1.5; invMT = invMT * osg::Matrix::scale(axesScale,axesScale,axesScale); _transDragger->setMatrix(invMT); } } Thank you! Cheers, David ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=41431#41431 _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
