Over the last couple of weeks I’ve been continuing my integration efforts between PolyVox and gameplay3d. This is proving to be extremely useful as a way of identifying the problems and limitations within PolyVox, especially as I haven’t worked with smooth voxel terrain for quite a while (since before Voxeliens). In particular I have been focusing on level of detail support, and as you can see below I have had some success:

The MeshDecimator class has recently been deprecated, and I’ve been saying for a while that down-scaling the volume data and running the Marching Cubes algorithm on this smaller data is probably a better way to achieve LOD for smooth terrain. There is even an example in PolyVox which demonstrates this on a sphere. However, doing it on a real world dataset has proved to be a bit more complex, and I can see now that some changes need to be made to the way PolyVox handles sampling outside a volume and to the way the VolumeResampler works. But in principle it does seem like a sound approach.

That said, there’s still an issue with cracks between the mesh patches where the LODs don’t line up exactly (you can’t really see this in the screenshot because it’s wireframe). Some tests have shown that simply overlapping the meshes slightly seems to be a viable solution, but again I need to make some changes to PolyVox to support this more naturally. Of course, the Transvoxel Algorithm is also a more robust solution which may make an appearance in the future.

Next up I’m expecting to look at physics integration for both the smooth and cubic styles of terrain.

Over the last couple of weeks I’ve spent some more time on our PolyVox+gameplay3d integration, and have added some basic editor functionality. Here’s how it looks at the moment:

You can paint on the terrain with the various materials, and there is also functionality to edit the shape of the terrain. This can even run on my mobile phone at a slow but useable 10-15fps. I realise the labels say ‘Brush Size’ twice, the second one should actually say ‘Brush Intensity’.

The main reason that I’m doing this is as research into the best way to handle multiple materials within a smooth voxel terrain. These have always presented a problem with  modelling and also with making nice material transitions. I think I’ve made some significant breakthroughs here so I’m hoping to write a research paper on the coming months… so if you want details on how it’s done you’ll have to wait for the that 😉

Over the last couple of weeks I’ve been doing some work to integrate PolyVox’s smooth terrain into RIM’s gameplay3d engine. This follows on from our previous work on cubic terrain. The smooth terrain is no more difficult than cubic terrain, and the main challenge has been designing the code in such a way that the integration elegantly supports both (as internally they have different voxel and vertex types).

The images below are again based on one of the data sets from Voxeliens, but this time we’ve run the data through the LowPassFilter to perform smoothing and basic triplanar texturing is also applied:

These screenshots are taken on PC but the test application does run on my mobile phone as well. It’s a bit slow though (20-30fps) which is probably because there’s no LOD present at the moment. It’s nice to be back to tech development are spending so long working on Voxeliens and we have some big ideas for the next engine 🙂