I tried today to implement some very simple LOD feature. Of course I searched the web before I tried to reinvent the wheel, but I didn't found what I searched for so I decided to write it by myself. It was more an exercise for me than something like a real feature.
Actually, I didn't want to write much stuff from scratch... that's why I use Irrlicht. And I actually like this engine. There's much love in it
. But sometimes I'm very frustrated when I intend to implement new stuff.Like so many people before, I wanted to do some kind of solar system. Now, when I get really far, planets become small and I don't see any reason to render them at full quality. Till now I used a simple call to ISceneManager::addSphereSceneNode().
So this is what I basically tried:
I knew that I had to inherit from ISceneNode, so I did that. I implemented the required stuff and compiled. Unfortunately ISceneNode has no default constructor. And there's nothing like a ISphereSceneNode. How can I profit from the ISceneManager factory then? ISceneNode has a copy constructor... suddenly I had that genius idea:
Code: Select all
class PlanetSceneNode : public ISceneNode
{
PlanetSceneNode::PlanetSceneNode (ISceneManager* Scene, f32 Radius)
: ISceneNode(*Scene->addSphereSceneNode(Radius,16))
{
}
virtual ~PlanetSceneNode () {
UNDEFINED_DTOR_WARNING;
}
virtual void render() {
this->render();
}
virtual const aabbox3d<f32>& getBoundingBox() const {
return this->getBoundingBox();
}
};
So each time I think that I've finally found the 'right design' for my class, I get another afterthought why it possibly cannot work. For example, I thought then, OK, whatever, I'll create a few instances with ISceneManager::addSphereSceneNode(), store them in my own class and switch between on render() calls and so on. But this means big overhead, and I would have to inherit from ISceneNode and implement ALL virtual functions anyways. This is would be so much unneeded code.
Very frustrating. It seems that it's a pain in the *** to build UPON existing features of Irrlicht. I would have to modify the engine each time (if I don't want to rewrite big parts of it) and recompile it. But this is utterly nonsense.
It's not the problem for me to actually do the LOD stuff - I would surely get it done somehow. But I'm rather speaking about the problem of building upon Irrlicht without the need of modifying the engine itself. I don't like to change the engine code, I have a bad feeling about it.
So, please help me.
What am I doing wrong here?
What is the 'correct' way to do it?
Thanks for reading!
or, again, copying irrlicht code to my own...resistance is futile... is it so difficult to extend and/or lengthy source ? How about again, making your own ? From mouse delta with mouse and rotate interfaces in your standard camera derived class ? well design concept or not, if you really make something serious after all you can still strip irrlicht for all unecessary and make your 'semi own' version... but I think that exactly is already part of the design concept...
