= HUD =
See also: Ticket #233,#252

== Author ==

[wiki:people/YuningChai Yuning Chai]

== What's HUD ==

A full description of HUD can be found under [http://en.wikipedia.org/wiki/Head-Up_Display WikiPedia].[[br]]

== HUD with Ogre == 

Ogre has its own class for HUD designing: CLASS OVERLAY. [[br]]
There are two ways to write an overlay, neither it can be written in a script, or it can be dynamically created in C++ file. 
All possibilities and variabilities for an overlay script are found unter [http://www.ogre3d.org/docs/manual/manual_38.html#SEC217 Ogre Tutorial].
For Windows Users there is already an editor made by Patrick Kooman: [http://www.ogre3d.org/wiki/index.php/Overlay_Editor Overlay Editor]

== Fall 2007 ==

See Printscreen: Version 2.0

== Spring 2008 ==

Instead defining the whole HUD in a single script, and then linking every object of the script into a C++ file, it is now possible to directly creating the HUD in a single C++ file. In orxonox.cc, only one command is needed:
{{{
HUD hud = new HUD(int zoom);
}}}
the idea is to create a flexible HUD, which can become bigger or smaller easily. 

A simple element of the HUD can be created as following:
{{{
Ogre:: OverlayManager& overlayManager = Ogre:: OverlayManager::getSingleton();
Ogre:: OverlayElement* element = overlayManager.createOverlayElement("Panel",name);
}}}

In the second step, it is to create few inherited classes to Ogre:: OverlayElement, so more complicated and often used elements can be easily implemented. There is a problem about inheritance: Ogre:: OverlayElement doesnt have a constructor for itself, and Ogre:: OverlayManager::getSingleton().createOverlayElement() only creates an OverlayElement, but not its inherited classes. I could not find out how to inherit Ogre:: OverlayElement, so I wrote classes, which have an OverlayElement as public variable and several functions to change this OverlayElement. 

Class Bar:
{{{
class _OrxonoxExport Bar
{

.....
.....

public:
  Ogre:: OverlayElement* element;

  Bar(Ogre:: Real left, Ogre:: Real top, Ogre:: Real width, Ogre:: Real height,
      int dir, int colour, std::string name);
  ~Bar(void);
  void reset(int percentage);
  void setColour(int colour);
  void show();
  void hide();
};
}}}

Single elements cannot be directly put into HUD, they have to be added into a panel at first. The panel will be set into the whole overlay afterwards. 
{{{
Bar* energyCounter;
Ogre::OverlayContainer* energyCounterPanel;

...

Ogre::Overlay* orxonoxOverlay = overlayManager.create("Orxonox/HUD"); 
orxonoxOverlay->add2D(energyCounterPanel);
orxonoxOverlay->show();
}}}



== TODO ==

 * To find out how to write letters or numbers with C files. 
 * To create more module classes.
 * To realize Radar System.

== Proposals ==
 * use SVG for drwaing - saves space, and is resolution indendant; drawback need to be implemented in OGRE/framework [[br]]
 * more suitable font.[[br]]
 * improve radar: removed grid, add distance rings[[br]]


== Printscreens ==

=== Version 1.0 ===

[[Image(HUD1.0.png,250)]]  

=== Version 2.0 ===

[[Image(HUD2.0.png, 250)]]