Re: [vos-d] SecondLife geometry
Sorry for the late reply, just noticed this discussion. Secondlife supports cutting but no boolean. You can link several links together, and position them one inside the other to simulate a new surface - but in truth, it will still be a group of separate primitives, and no boolean operations are possible. Infact, we've been asking for it for awhile. There are several types of graphics i've spotted in SecondLife: A terrain bumpmap - for the world's terrain, can be edited via a standard raw file. A poser avatar mesh - The avatars are poser 2 models. We believe they messed with the design abit, but thats what they are. Primitives - pretty much everything else, other then the standard issue skybox. Particles - Clouds, several UI effects, and other effects that can be generated via scripted objects. The physics engine treats all the objects as individual primitives. Infact, for this reason, physics-enabled objects have been artificially limited to 31 primitives - LL says that too many physical objects with more primitives then this can cause the physics engine of the local simulator to slow down drastically and possibly deep think and halt. Every primitive can stand for itself. Each of them has their own personal inventory which can contain symlinks to other objects, including their own personal instances of script bytecodes - enabling each primitive to be individually scripted and have its own programmed reaction, including communication with other primitives within the same object as they. Most of the complex 3D effects are currently achieved by commanding the various primitives to move or transform in a certain way to simulate all sorts of motions. Commanding the Root primitive will cause the entire linked set to move in the world itself. The physics engine is Havoc 1. It is running on the sim, sending updates on all objects to connected viewers. Objects will always continue the previously given movement and will even clip through other objects in the scene unless another command is sent as override. (Not very good for games - slow reaction time) After playing with various streaming 3D clients - from Active Worlds to Blaxxun, Plastic Planet, Caligari, Terangreal and even GuildWars (Zone art files are only downloaded on demand, when you cross the border or enter a building - from that point onward they are available on disk), I can safely say that Linden Lab's primitives method is pretty good for streaming: It provides the fastest results. With most systems I had to wait up to several minutes to download a complex scene. With SecondLife the wait is limited to 5 seconds at best, with everything else finishing to render as you move in about 30 seconds to a minute even in a very complex scene. The problem is - SecondLife have not progressed this technology very far beyond adding afew features such as new primitive shapes, light sources and flexible primitives. One feature that would be interesting to see would be the ability to fuse the edges of primitives together to create a skinned object on the client side, boolean operations, or even the ability to specify custom primitive designs. As long as the server see the primitives only as such or possibly nodes, it should be possible to create all sort of interesting effects purely client-side to enhance the graphics. On Jan 11, 2007, at 4:58 AM, Mark Wagner wrote: On 1/10/07, Reed Hedges [EMAIL PROTECTED] wrote: Does anyone know if you can do boolean operations with prims? I vaguely recall that you can apply a few cut out operations but not completely general prim-prim boolean ops?? You can perform various CSG-like transformations on prims, but SecondLIfe does not support CSG. I suspect that this is because the prims are converted into meshes for rendering: CSG on meshes is a non-trivial problem. It may also be related to the physics engine they use. -- Mark Wagner ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d
Re: [vos-d] SecondLife geometry
Isn't this called procedurally generated content? Not entirely unlike what they did with .kkrieger (http://en.wikipedia.org/wiki/.kkrieger) ... On 1/15/07, Or Botton [EMAIL PROTECTED] wrote: Sorry for the late reply, just noticed this discussion. Secondlife supports cutting but no boolean. You can link several links together, and position them one inside the other to simulate a new surface - but in truth, it will still be a group of separate primitives, and no boolean operations are possible. Infact, we've been asking for it for awhile. There are several types of graphics i've spotted in SecondLife: A terrain bumpmap - for the world's terrain, can be edited via a standard raw file. A poser avatar mesh - The avatars are poser 2 models. We believe they messed with the design abit, but thats what they are. Primitives - pretty much everything else, other then the standard issue skybox. Particles - Clouds, several UI effects, and other effects that can be generated via scripted objects. The physics engine treats all the objects as individual primitives. Infact, for this reason, physics-enabled objects have been artificially limited to 31 primitives - LL says that too many physical objects with more primitives then this can cause the physics engine of the local simulator to slow down drastically and possibly deep think and halt. Every primitive can stand for itself. Each of them has their own personal inventory which can contain symlinks to other objects, including their own personal instances of script bytecodes - enabling each primitive to be individually scripted and have its own programmed reaction, including communication with other primitives within the same object as they. Most of the complex 3D effects are currently achieved by commanding the various primitives to move or transform in a certain way to simulate all sorts of motions. Commanding the Root primitive will cause the entire linked set to move in the world itself. The physics engine is Havoc 1. It is running on the sim, sending updates on all objects to connected viewers. Objects will always continue the previously given movement and will even clip through other objects in the scene unless another command is sent as override. (Not very good for games - slow reaction time) After playing with various streaming 3D clients - from Active Worlds to Blaxxun, Plastic Planet, Caligari, Terangreal and even GuildWars (Zone art files are only downloaded on demand, when you cross the border or enter a building - from that point onward they are available on disk), I can safely say that Linden Lab's primitives method is pretty good for streaming: It provides the fastest results. With most systems I had to wait up to several minutes to download a complex scene. With SecondLife the wait is limited to 5 seconds at best, with everything else finishing to render as you move in about 30 seconds to a minute even in a very complex scene. The problem is - SecondLife have not progressed this technology very far beyond adding afew features such as new primitive shapes, light sources and flexible primitives. One feature that would be interesting to see would be the ability to fuse the edges of primitives together to create a skinned object on the client side, boolean operations, or even the ability to specify custom primitive designs. As long as the server see the primitives only as such or possibly nodes, it should be possible to create all sort of interesting effects purely client-side to enhance the graphics. On Jan 11, 2007, at 4:58 AM, Mark Wagner wrote: On 1/10/07, Reed Hedges [EMAIL PROTECTED] wrote: Does anyone know if you can do boolean operations with prims? I vaguely recall that you can apply a few cut out operations but not completely general prim-prim boolean ops?? You can perform various CSG-like transformations on prims, but SecondLIfe does not support CSG. I suspect that this is because the prims are converted into meshes for rendering: CSG on meshes is a non-trivial problem. It may also be related to the physics engine they use. -- Mark Wagner ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d -- QOTD: Violence is the last resort of the incompetent -- Isaac Asimov GPG Public Key: http://www.jargonjunkie.com/rants/scones.asc Website: http://www.jargonjunkie.com/ ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d
Re: [vos-d] SecondLife geometry
Does anyone know if you can do boolean operations with prims? I vaguely recall that you can apply a few cut out operations but not completely general prim-prim boolean ops?? Reed Mark Wagner wrote: On 1/10/07, Peter Amstutz [EMAIL PROTECTED] wrote: One thing I've been wondering about -- while their primitives seem to be a pretty clever solution to the bandwidth problem, is their graphics architechture completely committed to being based on prims? With the rest of the world being based on straight triangle meshes or surface patches, their graphics model seems to be completely unable to keep up with the state of the art in 3D graphics. One thing I like about the prim model is that it can be converted to raytracing and CSG with little to no effort. (Yes, you can raytrace meshes. But they look like raytraced meshes.) ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d
Re: [vos-d] SecondLife geometry
Someone answered on another thread that it is not. They do cutting but not CSG. chris On 1/11/07, Reed Hedges [EMAIL PROTECTED] wrote: Does anyone know if you can do boolean operations with prims? I vaguely recall that you can apply a few cut out operations but not completely general prim-prim boolean ops?? Reed Mark Wagner wrote: On 1/10/07, Peter Amstutz [EMAIL PROTECTED] wrote: One thing I've been wondering about -- while their primitives seem to be a pretty clever solution to the bandwidth problem, is their graphics architechture completely committed to being based on prims? With the rest of the world being based on straight triangle meshes or surface patches, their graphics model seems to be completely unable to keep up with the state of the art in 3D graphics. One thing I like about the prim model is that it can be converted to raytracing and CSG with little to no effort. (Yes, you can raytrace meshes. But they look like raytraced meshes.) ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d
Re: [vos-d] SecondLife geometry
On 1/10/07, Reed Hedges [EMAIL PROTECTED] wrote: Does anyone know if you can do boolean operations with prims? I vaguely recall that you can apply a few cut out operations but not completely general prim-prim boolean ops?? You can perform various CSG-like transformations on prims, but SecondLIfe does not support CSG. I suspect that this is because the prims are converted into meshes for rendering: CSG on meshes is a non-trivial problem. It may also be related to the physics engine they use. -- Mark Wagner ___ vos-d mailing list vos-d@interreality.org http://www.interreality.org/cgi-bin/mailman/listinfo/vos-d
