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View Full Version : PLZ trying to write enginge but dont know how to think :(



06-21-2000, 09:03 PM
Hm, well hopefully i got ur attention, i was trying to write a "engine" with opengl just simple loading of textures, maybe some lights, u know simple. well then i dont know how to begin, i am not sure how to do these common triangle strips, and i need someones simple modeler and file format so i can make model and load them up, can anyone tell me where i can find a tut on the strips, and the modeler and file format (a simple one that is)? plz help i am getting bored from pcs http://www.opengl.org/discussion_boards/ubb/frown.gif

Igor
06-21-2000, 11:00 PM
try www.codersger.de (http://www.codersger.de) there is a link to a site with 3d-engines, but instead of coding an OpenGL engine you should first code a software 3d engine, to understand the whole ****...

06-22-2000, 10:26 AM
Igor thank u i think http://www.opengl.org/discussion_boards/ubb/smile.gif i didnt say i wanted ppls engines, but i think u mean there will be modeler's and so on there(???), umm i am not making a software one cuz i started making one and i well need a brake http://www.opengl.org/discussion_boards/ubb/smile.gif
anyone else up for the try? http://www.opengl.org/discussion_boards/ubb/smile.gif

Glenn Upton
06-22-2000, 03:32 PM
Work your way thru NeHe's tutorials. Then you'll have a better handle on what you are trying to do. Is my advice anyway.

06-22-2000, 04:02 PM
hmmm, i am sorta doing that now, but that doesnt give me a modeler and a file format http://www.opengl.org/discussion_boards/ubb/frown.gif

06-22-2000, 08:05 PM
I also just started out with OpenGL. To have
something to render, I whipped up a very
simple text parser. It helped that I've been
living inside POV-Ray for most of my life :-)

Of course, modelling the next Lara Croft in text format is probably not going to be easy, but I stop at 20-polygon vehicles and other objects.

I had the basic datatypes scalar, vector and vertex, and maybe 10 keywords: "define" (for assigning names to values, for convenience), "quads", "triangles", "tristrip", "quadstrip", "trifan", "normal", "color", "scale", "rotate" and "translate" -- that's about it. You just read the text file into a list of objects, and when time comes to render, you call Render() on the objects, and they will run through the same commands that you put in the text file (if you don't have a bug, that is :-)

glPushMatrix() and glPopMatrix() helps a lot here, by the way.

(I actually extended the format a little more for recursive objects and multiple instances, but all in all it probably took less than 4 hours total).

Good luck!

Igor
06-22-2000, 08:14 PM
what modellers ? do you mean programms to make 3d modells ??? Than try .3ds .c4d .lwo !!! I prefer .3ds and after making my objects i convert them with 3D-Exploration (www.xdsoft.com/explorer/) to OpenGL .cpp code ! There is also 3dWinOgl which can do that but it makes the code slower ! 3dwinogl uses for every single triangle a glBegin/End and that makes your code very slow !!!

06-23-2000, 01:53 AM
bgl, i know what ur talking about i already sorta did it http://www.opengl.org/discussion_boards/ubb/smile.gif thx anywayz
IGOR, u the man!!!! http://www.opengl.org/discussion_boards/ubb/smile.gif hmm, it sounds cool but what exactly is the code?just a bunch of
glBegin(gltriangle) etc...hwo do i know to seperate objects and stuff i have to make a parser for it and load the data from the .cpp openl code?

06-23-2000, 01:59 AM
hmmm before u answer i really wanna thank u igor cause i was going for giving up and doing more 2d

Enzaro
06-23-2000, 07:50 AM
Explorer creates a C file containing the necessary code needed to display the object you converted. I can't quite remember what they look like exactly (left my output at home) but it contains the vertices, normals and indices for displaying the above. All of these are created into display lists for faster display. All you have to do is call the display function to show it. Dont forget to scale, translate or rotate first if you want it showing in a place other than center screen. If you do use the converter to convert to C code, all you have to do is #include this file into your VC++ project, and you are set. No need for a parser. http://www.opengl.org/discussion_boards/ubb/smile.gif

06-23-2000, 09:06 AM
WOW! thanx igor and enzro!and again WOW! http://www.opengl.org/discussion_boards/ubb/smile.gif
happy coding,
hazok/HELP ME!!!/how can i get ur attenti/bad3dcoder/the bug/loca2/loco/hael
i am a man with many names http://www.opengl.org/discussion_boards/ubb/smile.gif

Validus
06-24-2000, 08:15 PM
It is not really as hard as you might think to write a pharser. there is a doc by Jim Pitts that explanes the .3ds file very well and I think there is even some example code to look at. It is a bit harder to get tetures and stuff but just to get the vertex data, It only took a day to code that and if I had been able to see the example code that I found only after I finished it would have been esaar.

good luck http://www.opengl.org/discussion_boards/ubb/smile.gif

PeterParker
06-26-2000, 05:53 AM
Another method of importing complex geometry is in 3D-Studio Max the ascii output. It generates an ASCII Textfile with Vertex Coords, Face List and Smoothing Groups. But it has no TextureMapping :-( But for the beginning.. It is very easy to implement..