In this tutorial I will be showing you how to compile a model which uses some lod models to keep the polycount really low. Now this ins't a tutorial on modeling but I will be showing you how to optimise your model down quickly with some ok results. Now Before I start I must mention that this model is quite lowpoly anyway and probably won't need lod settings but this is just a demo. Also the model is quite basic so the texture work isn't great.
So the first thing I am going to do is export out this model (making sure it is centered on the origin) out to a .smd file. This must be placed in the folder you choose for the mod you are working with in order for ducttape to recognize it. Also at this point I will export my collision model which will be just a simple box.
Now we need to optimize our mesh to create our lod models. For the purpose of this tutorial I will only be creating one but you can always use this knowlege to create more levels. There are quite a few ways to do this now the way I prefer is to just go in and remove edges manually. But for big meshes this can be tedious and a waste of time so you can use the optimize modifier in max (or you applications equivalent) or finally you could use a program like Mesh-Lab or Polygon Cruncher (you can find a tutorial for this on eat3d.com. Now when creating theese model you need to take into account the affect on the silhouette of the model. If it changes to much you will get a kinda popping effect in-game. Now below you will see a before and after shot on this model.
Now the next step is to just export this model and open ducttape. Now this tutorial is for just getting a lod model to work with ducttape and so I won't cover basic compiling for that look at the documentation section for compiling a basic model. Now below is a screen shot of how I set up my lod setting in this case.
Here you see the steps to set up a lod setting for the model. Now on the other tabs there are similar dialogs but for changing the texture or bones etc.. at certain levels. Step 1 press the new button to create a new lod line inside the .qc which are shown in a list view dialog. Step 2 is changing the threshold level which is how far away it will be before the change happens (will show a good way to get this down later). Step 3 is to choose the model that will be edited at this level, you can do this by dragging the .smd from the side bar into the text entry box. Step 4 is to choose what should happen to the model and if you replace it choose the model that it will change to.
So that is pretty much it just go a head and compile the model as you would normally and check out you amazing lod setting in the HLMV.
Now this section is to show you really how to find out a good value for the threshold. So start by opening up the HLMV and opening a model that has lod setting (not necessary but useful) then go to the model tab and check the auto lod box (1). Next move the camera in and out whilst checking the LOD Metric value for a indication of what the threshold is at this point (2). Using this you can find a value that will look good for your model and then just edit the .qc.
