Hi, everybody.

I work with Open Inventor and am trying to make an object rescale as the camera moves, so that it appears the same size, no matter how far away is it from the camera.

The camera moves when I press a key and I set the object to redraw its scenegraph for the new camera position. I load the geometry of the object from a file every time it is rerendered.

This works file when the camera moves away and I need to make the object bigger. But when the camera moves closer, the object does not get smaller! It stays the same size as it got when the camera was furhtest away.

Any ideas?

Here is some code:
Code :
//Main
int main(int argc, char *argv[])
{
SoOneShotSensor	*sensor = new SoOneShotSensor (simulationStep, NULL);
root->ref();
 
myObject = new genObject();
myObject->buildtree(root);
//Update Scene
sensor->schedule();
...
}
 
//simulationStep
void simulationStep(void *data, SoSensor *sensor)
{
	...
	SbVec3f *cameraPosition = new SbVec3f
				(myPerspectiveCamera->position.getValue()[0], 
				 myPerspectiveCamera->position.getValue()[1], myPerspectiveCamera->position.getValue()[2]);
	myObject->setScale(cameraPosition);
	myObject->buildtree(root);
	sensor->schedule();
}
 
//myObject->setScale(cameraPosition)
void genObject::setScale(SbVec3f *cameraPosition)
{
	this->cameraPosition = cameraPosition;
	SbVec3f tempPos = SbVec3f(this->getLatitude(), 
					  this->getAltitude(), 
					  this->getLongitude());
 
 
	if (tempPos.length() == 0)
	{
		this->scaleFactor = 1;
	} else 
	{
		this->newScaleFactor = cameraPosition->length() / tempPos.length();
		this->scaleFactor = this->newScaleFactor;
	}
}
//myObject->buildtree(root)
void genObject:: buildtree(SoSeparator *root)
{
	this->group = new SoSeparator();
	root->addChild(this->group);
 
	this->model = new SoFile;
	model->name.setValue("OwnObject.iv");
 
	...
 
	this->size = new SoScale();
	this->size->scaleFactor.setValue(this->getScale(), this->getScale(), this->getScale());
 
	this->group->addChild(this->size);
	this->group->addChild(model);
 
 
};
 
//genObject
#pragma once
 
class genObject
{
private:
	float altitude;
	float latitude;
	float longitude;
	float scaleFactor;
	float newScaleFactor;
	SbVec3f *cameraPosition;
	SoSeparator *group;
	SoScale *size;
	SoFile *model;
 
 
public:
	genObject();
	void setAltitude(float alt);
	void setLongitude(float lon);
	void setLatitude(float lat);
	void setScale(SbVec3f *cameraPosition);
	void buildtree(SoSeparator *root);
 
	float getAltitude() {return this->altitude;}
	float getLongitude(){return this->longitude;}
	float getLatitude() {return this->latitude;}
	float getScale() {return this->scaleFactor;}
 
public:
	~genObject(void);
};