Debugging in full-screen Direct-X mode

[adamdalziel]

I am currently writing a 3D games engine using Direct Draw with Visual C++. So far I've created line vector objects but would like to sproose it up by introducing flat polygon filling & z-buffering.

However, I need to use the debugger but because the application runs in full-screen, page-flipping mode, it completely takes over!!!

Is there a trick of the trade here??

How can I use the debugger while running the application?????

Cheers, Adam

[Coder]

2 monitors are used, one for the Graphics output the other for the debugging.

How it's done, I don't know. I've never tried it before. Visit microsoft's site and check their DX 8.1 documentation, the DirectX Graphics ( D3D8.1 ) section has things about debugging in full-screen. I don't know if it's general ( i.e. applicable to DirectDraw ) but you might find it useful.

By the way, why don't you use DirectX Graphics?

[adamdalziel]

Ahhhh, so that's how you do it!! I only have one monitor output on my comp, so poerhaps I'll need to upgrade to a G-force card with double output???

Cheers, that's really helpful - Microsofts DX page is my next port of call!

PS- I've not heard of DGraphics (oops!) and am only aware of DDraw and D3D in this department. Is DGraphics better?

[Coder]

PS- I've not heard of DGraphics (oops!) and am only aware of DDraw and D3D in this department. Is DGraphics better?
Direct3D 8/8.1 is named DirectX Graphics to reflect the fact that it's a completely new design ( much better, actually ) that's used, along with the elimination of DirectDraw ( there's no DirectDraw 8/8.1, 7 is the latest & last version. There's going to be no more DDraw )

DirectX Graphics allows the programmer - in my opinion - to code amazing 2D & 3D graphics, and the 2D is much easier than DirectDraw.

[adamdalziel]

I see - yeah, I think it's v7 that I'm using. I know that I could make my life at lot easier by using D3D (or the 3D side of DGraphics) but I kinda wanted the challenge of building a 3D engine with only a line drawing function at hand - mad, I know!!

Cheers for the help & now have alot of research ahead of me (ahhhhhhhhh)

[MrWizard]

Ok so here's the deal with debugging full-screen apps. If you are running Windows2K you can do it. (maybe with others but i'm not sure) Just use your primary video card and then buy a little cheap PCI second one. It's pretty easy to setup and you can make the PCI one secondary and re-direct output to that monitor. Also, I believe DX8 comes with a "trace" tool that you can output to a windowed program. I think you can output message like
Trace( "Function Called, i = %d ", num1 ); Similar to Printf. And you can also trace error messages easily.

[Coder]

I kinda wanted the challenge of building a 3D engine with only a line drawing function at hand - mad, I know!!
It's great to do so. I believe most 3D programmers have tried it some time, I tried implementing a 3D engine using DirectDraw when I first started 3D programming. Although I didn't finish it ( I implemented all, until it came to Z-Buffering, and then the DX8 SDK was released, and I couldn't help but switching to DirectX Graphics. The gouraud shader had some problems, though and the Z-Buffering made the thing VERY slow [ Later, I read Paul "Midnight" Nettle's S-Buffer FAQ. This would've imporoved performance a lot] )

Doing rasterization yourself it excellent, it gives you an idea about what DirectX Graphics ( or more precisely, the display adapter ) does for you. Just don't keep on doing that forever, experiment with software rendering a little, then switch to either DX or OGL.

By the way, there's something I forgot to tell you. When debugging 3D apps ( games ), you don't need to debug in full-screen. Most engines have the ability to run in windowed mode, in which you can happily debug everything.
This is the way most people do it, since few people have 2 monitors.

[Nor]

I use a GeForce 4 card with TV out. And when I run and DirectX games I have to disable the secondary monitor or I crash.
Is there any fixes??