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 | | Re: Inverse matrix?
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| (...) I mean swap the OFF-diagonals, leave the diagonals as is. (...) (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Re: Inverse matrix?
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| (...) Just take the transpose of the 3x3 world rotation matrix and it should work as the inverse. Transpose means swap diagonals M[1,2] <=> M[2,1] etc. If this doesn't work I've misunderstood you. Tim (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Re: Inverse matrix?
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| (...) Hehehe, cool, I'll try that. Thanks! James (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Re: Inverse matrix?
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| Clarification! .... snip (...) I am using additional points to specify the location of feet. Combined with the model location, I have 3 points for the hip and feet. [now the following paragraph should make more sense] (...) (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Re: Inverse matrix?
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| (...) Arg. I thought this was going to be easy. I liked this part of the wikipedia article: "In practice, inverting a matrix is rarely required. Most of the time, one is really after the solution of a particular system of linear equations." Hm. I (...) (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Re: Inverse matrix?
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| (...) I just realised something... do you want a general inverse or a specific inverse? Some inversions are simple eg. a pure rotation can be inverted by taking its transpose and reflections are their own inverses. Tim (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Re: Inverse matrix?
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| (...) There really is no easy way to do it. Feel free to look at TCVector::invertMatrix in the LDView code if you want to see code that does it on a 4x4 matrix. To convert a 3x3 matrix into a 4x4 matrix, put the 3x3 in the top left, put a 1 in the (...) (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Re: Inverse matrix?
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| (...) The inverse of <1,0,0,0,1,0,0,0,1,0,0,0> is itself. To compute the inverse of a general 3x3 matrix (essentially what you need to do) is rather complicated. You could do it in a macro using Gaussian elimination [1]. Tim [1] (URL) (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Inverse matrix?
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| Does anyone know how to generate an inverse matrix. By inverse I mean it will undo the rotation of the original matrix. I thought the inverse of <1,0,0,0,1,0,0,0,1,0,0,0> was <-1,0,0,0,-1,0,0,0,-1,0,0,0>. In other words, multiply every value by -1. (...) (17 years ago, 7-Apr-07, to lugnet.cad.ray, lugnet.cad)
| | | | | Re: A question about an animation scene
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| (...) You are not specifying a custom clock value so your spline lasts from frames 1 to 121. You actually want to specify a custom clock value. Something like this: animate_by_spline (east_to_south, auto_banking (0) + spline_clock ( ..... ) )} The (...) (17 years ago, 6-Apr-07, to lugnet.cad.ray)
| | | | | Re: A question about an animation scene
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| (...) --snip-- (...) Hi Eduardo, The spline macro would be useful too ;) Tim (17 years ago, 4-Apr-07, to lugnet.cad.ray)
| | | | | A question about an animation scene
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| I have made a scene where a car follows a spline this is the main co ---...--- object { car_dot_dat matrix <0,0,1,0,1,0,-1,0,0,0,0,0> #if (version >= 3.1) material #else texture #end { Color7 } //translate<-960,-24,1860> rotate -90*y (...) (17 years ago, 4-Apr-07, to lugnet.cad.ray)
| | | | | RACHAL Changeover
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| Hi all, It's a day late but we changeover from RACHAL 1 - Atmosphobic to the all new RACHAL 2 - RACHAL Impossible today. Thank you very much to everyone who submitted an entry. I really enjoy seeing what you've all come up with and it we some (...) (17 years ago, 1-Apr-07, to lugnet.cad.dev.org.ldraw, lugnet.cad.ray, lugnet.announce, FTX) !
| | | | | Re: Light is too bright!
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| (...) In my 1998 Christmas picture (URL) (go to the end of the page) I hand adjusted the lights (one inside each candle) quite a bit. One important part was the material settings (Color46_t), as the clear L3P parts are much *too* clear. Most of the (...) (17 years ago, 26-Mar-07, to lugnet.cad.ray)
| | | | | Re: Light is too bright!
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| (...) Wow! Thank you! I didn't know that. I tried some different options, and found that the "black" light (color 0, which isn't really black) surpringly produced the best balance between taillights noticably on and not spreading too much red light (...) (17 years ago, 25-Mar-07, to lugnet.cad.ray, FTX)
| | | | | Re: Light is too bright!
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| (...) I just did before I read your post! (Just called it test.dat instead...) And it really works, the problem is POV will not inline the light into the position of SOFLIGHT.DAT but rather <0,0,0> of the POV world. This makes it more complicated, (...) (17 years ago, 25-Mar-07, to lugnet.cad.ray)
| | | | | Re: Light is too bright!
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| (...) I notice you're using white as the color for light.dat. Since L3P pays attention to the color of the light, you can use a much darker shade of gray. The following was done with a light inside the trans red brick with a color of 0x02141414 (...) (17 years ago, 25-Mar-07, to lugnet.cad.ray, FTX)
| | | | | Re: Light is too bright! [DAT]
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| (...) Hi Tore, Try something like the following Tim ------- SOFLIGHT.DAT ------- 0 Soft Pov-RAY Light Source 0 Name: SOFLIGHT.DAT 0 Author: Tim Gould based on work by James Jessiman 0 Unofficial part 0 L3P IFPOV 0 light_source { <0,0,0> color rgb (...) (17 years ago, 25-Mar-07, to lugnet.cad.ray)
| | | | | Re: Light is too bright!
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| (...) Thank you, Anders, I think that should do it. But the thing is, in LDA I try to do everything before running it all trough L3P. Adding post-processing to the steps already involved in LDA is not very appealing to me. And after the most (...) (17 years ago, 25-Mar-07, to lugnet.cad.ray)
| | | | | Re: Light is too bright!
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| (...) They should probably be less bright, you can multiply the whole RGB triple by a constant less than 1: ... 0.4 * <r, g, b> It would also help changing the 'fade_distance' and 'fade_power' to make them not shine so far. Or you could change them (...) (17 years ago, 25-Mar-07, to lugnet.cad.ray)
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