November 2012 - Openflipper - lists.rwth-aachen.de

Changing the size of an object
by Andrea Scholl 21 Nov '12

21 Nov '12

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Support for DXF file format
by cornelis.bockemuehl＠holcim.com 09 Nov '12

09 Nov '12

Dear OpenFlipper maintainers, Are there any plans to eventually support also DXF as an I/O file format in OpenFlipper? I understand that this is just the question for somebody to write a corresponding plugin. After having successfully compiled and built the OpenFlipper sources from SVN, I could even imagine to write and contribute some basic support myself, at least as far as my own interest in that format goes: supporting plain triangulated meshes without any further "decorations" like normals, textures etc. I would use for that purpose the DIME library (open source, rather old, but still doing its job so far...) which I changed so far that it now works with double numbers instead of float only internally. I guess that this would be a question of a few more hours to get that running on my computer. Much more of a problem I see in the integration into the OpenFlipper system: How to handle the extra DIME library? How to integrate all that license stuff properly? How to tell that fabulours CMake system that there is now another library to take care of? etc. etc. And since I am having absolutely no clue about that CMake magic, nor with these license subtleties, I would spend probably much more time with these issues than with the actual implementation of the DXF plugin! Bottom line: from my part, I have no objections against integrating any such DXF plugin into the main OpenFlipper project, but I see many technical and understanding problems on my side in terms of realizing such an integration properly! An alternative for me only would of course be to build such an extension to the OpenFlipper only for myself and my colleagues, for our own work. Regards, Cornelis Bockemühl _____________________ Cornelis Bockemühl Holcim Group Support Ltd Cement Manufacturing Services Materials Technology Reserve Evaluation and Quarry Planning Im Schachen CH-5113 Holderbank Phone +41 58 858 51 30 Fax +41 58 858 51 51 cornelis.bockemuehl(a)holcim.com www.holcim.com Holcim – 100 years of Strength. Performance. Passion. This e-mail is confidential and intended only for the use of the above named addressee. If you have received this e-mail in error, please delete it immediately and notify us by e-mail or telephone.

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Coordinates problem
by cornelis.bockemuehl＠holcim.com 05 Nov '12

05 Nov '12

Dear OpenFlipper friends and developers, We are just now running into a problem while using the OpenFlipper for topo modelling and model simplification with the Decimater. The point is that geographical coordinates tend to be large numbers, but in some way you can say that the most significant digits are the least significant ones - because they never change throughout a model! The problem is that once we have "decimated" a model and want to write it out to an OBJ file, the least significant digits are cut off by the C++ automatism of switching to exponential notation if numbers are getting large: 4522765.277 -> 4.52277e006 Which means: rounding to the next 10m occurs - not really acceptable! Of course we are already practising the workaround of first shifting the coordinates to something lower, then do the OpenFlipper treatment, then shift back. But of course it would be nicer if the OpenFlipper would simply do the output with some explicit fixed formatting. Currently the code that outputs the coordinates in OBJ format is the following: // Write out vertex coordinates _out << "v " << v[0] <<" "<< v[1] <<" "<< v[2] << std::endl; This code is at FileOBJT.cc(299). Would it be possible to add some formatting to such output lines, in order to make it easier to work with large coordinate values? Or is there a danger that in such a case there would be people complaining that they are now not any more able to work in picometers properly? ;-) Regards, Cornelis _____________________ Cornelis Bockemühl Holcim Group Support Ltd Cement Manufacturing Services Materials Technology Reserve Evaluation and Quarry Planning Im Schachen CH-5113 Holderbank Phone +41 58 858 51 30 Fax +41 58 858 51 51 cornelis.bockemuehl(a)holcim.com www.holcim.com Holcim – 100 years of Strength. Performance. Passion. This e-mail is confidential and intended only for the use of the above named addressee. If you have received this e-mail in error, please delete it immediately and notify us by e-mail or telephone.

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