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novation
09-02-2003, 11:55 PM
Warm greetings to everyone,

I am writing a program which extracts information from a database.

I would love to have this info be displayed with OpenGL. To start I will probably use Python because its the only thing I know http://www.opengl.org/discussion_boards/ubb/smile.gif

I could just start coding, but asking first might help me get some 'shortcuts' from long time users. Or perhaps someone will hint its just not possible http://www.opengl.org/discussion_boards/ubb/wink.gif

I want OpenGL to:

- Draw a circle with text in it
- Draw circles around a centre circle
- Connect the circles with lines

To start with, this would kick serious ass!

Would it be possible, with OpenGL, too:

- zoom in & out (without loosing quality of text!)
- write text around the edges of the circle
- 'fly' over the screen

Ok any and all help, tips, hints, pointers are more then welcome!

Warm regards,
Frans

Orzech
09-03-2003, 01:21 AM
Hello!

Of course you can do all this things in OpenGL. OGL is a great graphics API. I am just not sure if it's good approach to learn OpenGL only for doing some database visualization. Sure - using it can give you really cool results but there are easier ways of doing this kind of graphics than learning OpenGL. If you want to learn how to use OGL - that's great. I just wanted to say that you can save a lot of time if you choose some easier way.

[This message has been edited by Orzech (edited 09-03-2003).]

cg-hci_novice
09-03-2003, 06:00 PM
If you do decide to use OpenGL for the purpose mention, the following site may also be helpful to brainstorm off of since there are some similarities to what you are interested in doing (flying, etc.):
http://www.evl.uic.edu/aej/488/index.html

Hope this is useful.

zeckensack
09-03-2003, 07:25 PM
You need a flexible font renderer for the stuff you've mentioned. Note that OpenGL is a fairly low level (yet flexible) rasterization library, so it doesn't directly support font rendering at all. There are multiple ways to accomplish it, the most popular picks being textured quads and pixel rectangles (bitmaps).

Whipping up a good font renderer is not an easy task for a "first OpenGL project".
Try getting familiar with single texturing and alpha blending first, before you try to do this. It'll save you a lot of frustration.

OTOH, the circles and lines should be fun http://www.opengl.org/discussion_boards/ubb/smile.gif

novation
09-04-2003, 01:44 AM
Ok thanks for your kind replies! I will try and make this happen :)

Frans