ddraw vs. d3d...

[SparkyGoBlue]

Per recommendations on this forum I set my MAME ini video to ddraw (I use a TV with s-video for my monitor), but I've found that some games look significantly better using d3d.  Specifically, donpachi, dodonpachi, and ghosts 'n goblins look a million times better using d3d over ddraw.  Ddraw seems to do a nice job with older games like Donkey Kong and Pac Man.

Is there any kind of rule for what games look better with d3d over ddraw, or is it a trial and error thing?

[TheManuel]

For my money, ddraw is always better if you dont use hardware stretch because hwstretch makes the image look blurry.
But then, you won't be able to fill the entire screen in many games.  The problem with D3D is that it adds odd pixels to shoe-horn the original image into the resolution you are displaying (hwstretch does the same but at a finer scale, hence the bluriness).  However the image is as sharp as ddraw without hardware stretch.  It is a trade-off but I find the blurness much more objectionable that the odd pixles of D3D which on a TV are not too obvious except perhaps on graphics that respresent fine meshes and maybe other situations I have not encountered.

Another way I was exploring but did no have much success on ATI cards is creating custom resolutions that are exactly twice the game you are trying to display.  So for instance, for CPS-3 games, create a custom 384x448 resolution (only the vertical needs to be doubled) and run it on MAME with ddraw and no hwstretch.  I got great results with a laptop that had an NVidia card in it with S-video out but could not get it to work with the ATI Radeon 7500 on my actual MAME machine.  Also, the ATI drivers do not allow you to add resolutions easily like the NVidia ones do.  You would have to add them manually to the registry on the DALBSDNonStandardModes key.

Hope that helps.

[SparkyGoBlue]

Maybe I'm doing something wrong with ddraw (I have hwstretch set to 0 and switchres set  to 1), or maybe It's my video card (Radeon 2400HD), but the difference between ddraw and d3d on donpachi and dodonpachi is so striking, that I can't imagine anyone wanting to use ddraw over d3d with these games.

TheManuel, have you tried d3d with these games?  I'd love to hear if you're seeing the same differences I am.

[TheManuel]

I'll try to check tonight at home.
Can you describe in what sense one looks better than the other?

[SparkyGoBlue]

Can you describe in what sense one looks better than the other?

With d3d I get sharper, crisper, and more detailed graphics that fill up the entire screen (no distortion) over direct draw with donpachi and dodonpachi.

[Ummon]

Yeah, it's because you have switchres enabled. This means Windows will try whatever default resolution it's capable of - in this case probly 400x300, or maybe 640x480, depending on the game. TheManuel was trying to get native-like resolutions, but since it wasn't straight RGB, I don't know if it really was viable.

D3D still stretches, but by floating point precision, whereas DD is by integer values. I haven't tried a tv yet, but especially if using S-video, I'd guess just use D3D for all games, and depending on the game set the 'prescale' to 1 or higher. I've found with my 27" multisync monitors that since the dot pitch is different than a standard 19" arcade monitor, I prefer games at prescale=1, regardless of using DD or D3D. 27" SD TVs will have similar, or larger, dot pitch to my monitors hence I'd bet prescale=1 or more would be preferable.