From the manual:
Quote:

PANEL* name = { ... }
Panels are the basic elements for 2D games as well as for the user interface - the GUI - of 3D games. They are rectangular areas with a simple image oder more complex elements like texts, numbers, instruments, buttons or other controls. They move over the screen and can be used for cockpits, dashboards, inventories and inventory items, buttons, background screens or 2D sprites.
Example:
PANEL* aircraft_pan =
{
pos_x = 4; pos_y = 4;
digits(0,0,4,digit_font,1000,player._rpm);
digits(60,0,4,digit_font,1,player._speed);
digits(120,0,4,digit_font,1,my_height);
window(200,0,40,20,"compass.pcx",compass_pos.x,compass_pos.y);
flags = VISIBLE;
}
Remarks:
Scene antialiasing settings in the 3D card settings menu can make panels and bitmap fonts look blurry, depending on the 3D hardware and driver version.
See also:
bmap, layer, pos_x, pos_y, alpha, flags, button, vslider, hslider, window, digits, mouse_map, on_click



This is a good start to read about panels. You can show / hide panels by setting / resetting their visible flag. If you want a quick way to throw together such a panel have a look at "Panel Editor" in the manual. Looking at the code created by the panel editor might even be a good start to get you feeds wet in this topic.

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