Why not use the mathematical description of the landscape directly and solve it? Your graphical detail would go up a 1000-fold and you could even make it dynamic. Polygons are so oldschool... ;-)

Quote:Original post by swiftcoder

Quote:Original post by spinningcube Why not use the mathematical description (force field) of the landscape directly and raytrace or ray-march it? Your graphical detail would go up a 1000-fold and you could even make it dynamic. Polygons are so oldschool... ;-)

Have you ever tried this yourself? My (admittedly naive) implementation is lucky to break 5 fps for un-shaded terrain, on an high-end gaming machine, because of the cost of evaluating the noise functions many times per ray.

Yup I have. You need good data structures, clever optimizations, parallelization and many simplifications. I do have a good computer i7 Intel and some pretty fast memory. It could run faster on a GPU but I never bothered. And if looking at that polygonal model of his I say he could get away with only rendering the landscape in a 320*200 window or similar and scale all the buffers (colors, z etc...) to match the rest of the scene.

Quote:Original post by spinningcube

Quote:Original post by swiftcoder

Quote:Original post by spinningcube
Why not use the mathematical description (force field) of the landscape directly and raytrace or ray-march it? Your graphical detail would go up a 1000-fold and you could even make it dynamic.

Polygons are so oldschool... ;-)

Have you ever tried this yourself?

My (admittedly naive) implementation is lucky to break 5 fps for un-shaded terrain, on an high-end gaming machine, because of the cost of evaluating the noise functions many times per ray.

Yup I have. You need good data structures, clever optimizations, parallelization and many simplifications. I do have a good computer i7 Intel and some pretty fast memory. It could run faster on a GPU but I never bothered.

And if looking at that polygonal model of his I say he could get away with only rendering the landscape in a 320*200 window or similar and scale all the buffers (colors, z etc...) to match the rest of the scene.

I still think you can use a ray-marching approach but limit yourself to a low resolution, then scale this resolution up to fit the rest of your scene (like the tree or players etc...), then texture and shade it on the gpu with a deferred shading pass. The result will be much nicer and you can realistically run it with a much lower resolution. There will be trickery in up-scaling the image to fit the higher resolution forward rendered stuff (basically an upsampling problem) but you can also use it to do early culling for example.

Quote:Original post by spinningcube
I still think you can use a ray-marching approach but limit yourself to a low resolution, then scale this resolution up to fit the rest of your scene (like the tree or players etc...), then texture and shade it on the gpu with a deferred shading pass. The result will be much nicer and you can realistically run it with a much lower resolution. There will be trickery in up-scaling the image to fit the higher resolution forward rendered stuff (basically an upsampling problem) but you can also use it to do early culling for example. I would go with ray marching as it's the simplest one and distance calculations boil down to dist square tests. But ok who would like to have a completely dynamic terrain anyway ;-)

The terrain you are looking at is a cube and already encoded in a very good structure. As for texturing, lighting etc... That is easier to do in a deferred pass as you can extract normals and uvs and any other parameters from the emitters directly. Terrain self shadowing would be easy as you can shoot out an extra ray into the light direction and check for intersections. Mixing it with other geometry is as easy as you just populate the z buffer from your image, with a texture uploaded on the GPU. Now why there are not more examples? I think there are not more examples because people have not tried it enough that's all.

Quote:Original post by c_olin What about physics? I will need to have localized areas where objects can interact with the terrain. Wouldn't those areas have to be polygonized for the physics system?

Nope, no need as you can as well there shoot rays for contacts with the surface or just do distance tests. But hey, if you want just finish it with polys for now and then as a fun experiment check how it would be with raymarching. No hurt in that, right?