 | | Several replies to CLIPPING / WINDING
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R> If you keep changing states (turning backface culling on/off or R> changing front faces from CW to CCW) very often, you'll get a *slower* R> rendering in OpenGL (don't know about D3D). And remember that in a R> couple of months nVidia's GeForce (...) (25 years ago, 18-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) I understand that you would be allowed to have as many "0 CCW"/"0 CW" lines as you want. This will hurt performance and of course, it would be better if you could use only 1 call per part. (...) You don't need to do that with LDraw files, (...) (25 years ago, 18-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) In fact you can, use as many as you like, but that it's not the goal. if you read my previous mail, following this one I'am replying, you got the ideia that no WINDING meta command is the ideia, if the .DAT is well optimized. If someone want's (...) (25 years ago, 18-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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Rui Martins wrote in message ... (...) I am trying to find out when to actually start clipping. You say "every .DAT file which has tris or quads is a candidate for CLIPPING", but when can a program use that info? Would you require an unbroken chain (...) (25 years ago, 19-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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Rui Martins wrote in message ... (...) Wait a minute, you were not going to actually send winding state changes to the graphics engine? Simply keep track of the state yourself and send either vertices 1,2,3 or 3,2,1. The part author can use as many (...) (25 years ago, 19-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) Sure, that can be done but there's the "0 UNKNOWN" or "0 DOUBLE-SIDED" case, and you'd have to send the triangles twice if you don't want to change the state. Leonardo (25 years ago, 19-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) We both want the same thing, now we need to make everybody agree with us :) (...) I sort first by color and then by line type. I have everything pre-processed and I don't use glBegin()/glEnd() to render. (...) From my personal experience, (...) (25 years ago, 19-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) NO, I said that, to be used when optimizing the existent files, not when rendering the optimized files. (...) I never said that ! (...) I think that depends on the host processor that you have and your specific graphics board (2D/3D) ;) (...) (...) (25 years ago, 20-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) By candidate, I meant, someone could optiomize it, a place a 0 CLIPPING ON meta-command on it, and get some benefit. If you use enable clipping, but you have no graphic primitives in your file (assuming clipping is stryctly local), than you (...) (25 years ago, 20-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) That can be done, but you will probably suffer a performance hit, because, most hardware, just use a bit, to keep track of the state. Just minimize the use of the 0 CCW and 0 CW meta-commands, to boost performance. When optimizing existent or (...) (25 years ago, 20-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) Great ! (...) Don't be pessimistic ! As soon as people see that their models render twice as fast, they will start using the new features. And a utility to make the optimization job easier would make a big difference, to all the lazy people ;) (...) (25 years ago, 20-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) That's not true. If a super-file is not certified, then there's no way to tell if the subfile is normal or inverted. So when a file is referenced by a non-certified super-file, it can't be clipped, even if the referenced file is certified. (...) (25 years ago, 20-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) This is a problem of the current design (the one beeing used now). You didn't knew in the past, because you didn't have the 0 INVERT meta-command. So you can only assume it' NOT inverted. If for some reason, it is inverted, then the old .DAT (...) (25 years ago, 20-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) No. With current files, you don't know, so you can't assume anything. (...) No, inversions are common. (...) Right. So non-wound-up files can't be backface culled. I don't see what you're getting at here. (...) But we don't get to specify what (...) (25 years ago, 20-Oct-99, to lugnet.cad.dev)
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| | Re: Several replies to CLIPPING / WINDING
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(...) Sorry, you are right here. I allways think in some form of winding (CW or CCW) so this one slipped me, once again sorry, you are right. Can't assume nothing. (...) what I said was relative to my way of thinking, without the previous sentence, (...) (25 years ago, 21-Oct-99, to lugnet.cad.dev)
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