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10-10-2003, 01:23 AM
sir,
I am developing a GUI based open-GL editor based application for displaying of plots with text. In this application, I would like to know how to create pull down menus and dialogue boxes in a application. Please let me know the source code or procedure to construct.
bhasker.
Please mail me at : "bhaskart@isac.ernet.in"

virtualchetan
10-10-2003, 05:27 AM
http://www.cs.unc.edu/~rademach/glui/ http://glam.sourceforge.net/ http://ngl.sourceforge.net/

147-2
10-10-2003, 09:43 AM
Please, the forum is here not only to answer your question for you, but to also make the answer available to the rest of the world (which may be very interested).

As to the answer to your question, I use glRect()s in an ortho view. For a pull down menu, you need a menu bar up top. When a user clicks, you know where that user clicked, so if it is on the menu bar, you "show" a menu. Here it may be useful for you to know a decent mechanism for "showing". Suppose you have a "window manager" class with a linked list of "components" being drawn. These components may be windows with their own components in them, or may be strange things like pulled-down menus or menubars. When a menu is clicked, it just sticks it's "pulled down menu" component into that list. When an item is selected or somehow the menu is "shut up" then you remove the item from the list.

An alternative technique would be to have the window manager draw the menubar. The menubar "draws" each menu. If the menu is pulled down (by virtue of a boolean variable in the menu class) then it draws the entire menu in its pulled down state.

After a bit of head scratching, Im sure you'll be good at creating window components in OpenGL. It didn't take long for me to understand the Tao of Window components :P