943,901 Members | Top Members by Rank

Ad:
May 14th, 2008
0

windows graphics... history?

Expand Post »
Well I made it through my first semester of an MSCS. Almost. This summer I want to build a game. I am trying to understand a little bit of the history of Windows graphics and am a bit confused. There's WinAPI. There's OpenGL. There's DirectX. As I understand it, OpenGL was initially offered on NT platforms for high end engineering (CAD) apps and required high end (at the time) hardware. But isn't it a Unix based graphics library? So then some guys at Microsoft (Eisler, Engstrom, etc...) decided lower end PC's needed graphics libraries for games and introduced DirectX. Direct3D is a subset of DirectX for 3D routines specifically. Does Microsoft still offer OpenGL? Is it open source or must be bought from SGI? If a game program calls a DirectX routine which can be done in hardware with the right graphics card, DirectX is responsible for implementing the call either through the available hardware (faster) or through its own software routine (slower)? When does DirectX know the graphics card capabilities, at run-time, or when the game is compiled? Where does WinAPI fit into all this, does it sit on top of DirectX or is totally separate. What is a good source of reading for all of this?

Thanks ahead of time.
Similar Threads
Reputation Points: 11
Solved Threads: 0
Newbie Poster
drichird is offline Offline
16 posts
since Sep 2007
May 14th, 2008
0

Re: windows graphics... history?

Ok, on windows you can use GDI, DirectX and OpenGL to create games.

GDI should not be used for any games in my opinion, it is not hardware accelerated and on vista due to the software / hardware bliting it has become even slower! If you try to make a game in this you will quickly hit the wall. GDI is meant to be used for creating windows applications, not games.

DirectX is only availiable on Windows and XBox, DirectX isn't in my opinion as good as OpenGL however OpenGL has a horrible plugin system. OpenGL can do more but DirectX can do more nativly. The plugins are really inconveniant requiring differant versions for each graphics card manufacturer. OpenGl can be used on Linux, Mac, Wii, PS3 in addition to windows. So thats another advantage.

OpenGL is implemented by differant vendors, therefore some are open source and some are closed source. The capabilities of the card are of coarse only known when the program runs. GDI is completly seperate, however if you want so some reason you can hybrid DX and GDI but the hardware/software swap is slow.
Last edited by ganbree; May 14th, 2008 at 9:54 am.
Reputation Points: 17
Solved Threads: 0
Light Poster
ganbree is offline Offline
28 posts
since Apr 2007
May 16th, 2008
0

Re: windows graphics... history?

>> Where does WinAPI fit into all this
That is the Windows operating system functions. OpenGL, DirectX, etc are wrappers around win32 api functions. You can do windows graphics without OpenGL or DirectX, but you can't do OpenGL without the WinAPI.
Sponsor
Team Colleague
Featured Poster
Reputation Points: 5608
Solved Threads: 2282
Retired and Enjoying Life
Ancient Dragon is offline Offline
21,953 posts
since Aug 2005
May 17th, 2008
0

Re: windows graphics... history?

OpenGL no more 'wraps WinAPI functions' than any other program or library that happens to run on Windows. OpenGL is platform agnostic, the need for Windows API with OpenGL apps is to get access to the driver frontend, and ( perhaps ) obtain a window / device context, although OpenGL itself mandates no windowing method specifically. Maybe the software reference implementation that ships with windows wraps WinAPI calls, but that's not the version of OpenGL that most gamerz see ( install graphics card drivers and you get the driver manufacturers accelerated OpenGL driver, which should go as direct-to-the-card as possible. I have no idea what they put in their drivers, but I'll bet they make as little use of the Windows API as they can get away with ).

Same with DirectX, it is supposed to go 'under' the API, as in, provide as close-to-the-metal access to the graphics card as is feasible, card vendors provide the implementation, and if this uses WinAPI in any way, thats secondary to using the features of the hardware.
Moderator
Featured Poster
Reputation Points: 522
Solved Threads: 64
Veteran Poster
MattEvans is offline Offline
1,091 posts
since Jul 2006
May 27th, 2008
0

Re: windows graphics... history?

..., but you can't do OpenGL without the WinAPI.
Linux!
Reputation Points: 27
Solved Threads: 3
Light Poster
Grigor is offline Offline
26 posts
since Jan 2007

This thread is more than three months old

No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.
Message:
Previous Thread in Game Development Forum Timeline: Save real Pinball. Please.
Next Thread in Game Development Forum Timeline: Some Basic Game Development questions.. for my nephew





About Us | Contact Us | Advertise | Acceptable Use Policy
Forum Index | Build Custom RSS Feed


Follow us on Twitter


© 2011 DaniWeb® LLC