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pawilliams

OpenGL OpenGL Vs. DirectX

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Sorry but, geez! if you want ppl''s honest appinions don''t go to a board where ppl like opengl more! :>

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Direct3D, which is the only part of DirectX against which it is fair to compare OpenGL, is essentially OpenGL.

D3D uses matrices, vertexes and materials. GL uses matrices, vertexes and materials.

D3D places drawing commands between BeginScene() and EndScene(). GL places them between glBegin() and glEnd().

D3D is built upon DirectDraw, which in turn is built upon the GDI. Yu can''t learn DirectDraw without first knowing a little about the GDI, and you can''t learn D3D without first knowing a little about GL. Conversely, GL exists ''as is''. Using glut, you need only use a few lines of code to prepare OpenGL for use. However, you don''t get to use the accelerated 2D features provided by a DirectDraw-like system.

Signatures? We don''t need no steenking signatures!

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Mayrel, isn''t is so that since DX8, Direct3D and DirectDraw have merged into one DirectGraphics API?

Dirk =[Scarab]= Gerrits

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quote:
Original post by Mayrel
D3D is built upon DirectDraw, which in turn is built upon the GDI.


Then why is Direct Draw faster than GDI ? Isn't Direct Draw an alternative to GDI. Is that not the entire purpose of DirectDraw (and hardware acceleration).
It is true that you can use GDI together with DD but is makes the program run slower.

quote:
Original post by Mayrel
Yu can't learn DirectDraw without first knowing a little about the GDI,


Why not? I did !!


quote:
Original post by Mayrel
and you can't learn D3D without first knowing a little about GL.

I don't know a thing about D3D or OpenGL but I'm sure you are wrong. I would really love to hear you tell us why you have to know OpenGL to learn D3D !


Edited by - granat on November 1, 2001 3:54:41 PM

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Do a bunch of searches on Google.

Look for Chris Hecker''s webpage. I think it is at www.d6.com/checker

Search for recent posts by John Carmack at Slashdot.

Other than that, you won''t find much.

My personal opinion, stop comparing and start coding. *Better* is subjective. Use what you like.

SL

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D3D is more applied and extensive,it has many functions to help u with simply graphic-programming.but as we all know,opengl has a more strong capability and can be well replanted to other platform.

all these become the clag of selecting d3d or opengl for 3d programming,but perhaps it''s better to learn both of them.


just my opinion.

jerry2
Programming,make a whole new world.

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quote:
Original post by granat
Then why is Direct Draw faster than GDI ? Isn''t Direct Draw an alternative to GDI. Is that not the entire purpose of DirectDraw (and hardware acceleration).


I was talking about learning DirectDraw. The concepts of D3D are built upon the concepts of DD, which are built upon the concepts of GDI.

Personally, I think that should have been clear from the rest of the post, but if you honestly thought I meant exactly what I said, I apologise for being unclear.
quote:

Why not? I did !!


You are certain that you''ve never learnt any GDI? You didn''t use CreateWindow? Didn''t load an image into a DC and blit it to a DirectDrawSurface?
quote:

[quote]Original post by Mayrel
and you can''t learn D3D without first knowing a little about GL.


This is a stupid typo on my part. I intended to say DD (as in, DirectDraw).

Signatures? We don''t need no steenking signatures!

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