mame2003-plus: hundreds of new games, improved input, features, new bugs - now with runahead support

grant2258

alpha = 0.3
to the backdrop

UDb23

@grant2258 If it works that way, we are all happy.
From a logic point of view it doesn’t make any sense as that alpha (according to mame docs) should be the transparency of that layer. In this case sets the backdrop transparency to 30 percent ?!! There is nothing below the backdrop.... but it makes the games screen on top 100 percent visible ... weird.

Anyway, as said, if that’s the solution we’re glad you found it and will use that settings.

Once we finish all this testing it makes sense to summarize the findings in a specific doc/wiki.

UDb23

@Riverstorm thanks a lot. Will use that setting for some more experimenting with other backdrops.
Will also be interesting to see how it works with vector games.
Keep you updated.
Maybe we should create a dedicated thread for the artwork/backdrop testing, findings and docs.

grant2258

@UDb23 if you remove this code you dont need the alpha

https://github.com/libretro/mame2003-plus-libretro/blob/644b581886abe9b9272cf8027088754b31583ac2/src/vidhrdw/8080bw_vidhrdw.c#L55-L59

Riverstorm

I did update from source and added alpha=0.3 and it did make the shields and ship solid but it has a side effect. If you look at the pic closely it has a light green box around the shields and ship.

@UDb23 - I think once a position has been calculated for a specific backdrop size and game size it will be reusable. So Backdrop: 1920x1080 Game: 896x1080 Position: 0,-0.57142,1,1.57142 is done. I think several will be identical once 3:4 and 4:3 games are calculated. Space Invaders is a "weird" resolution 0.83:1.

grant2258

thats not a side effect its the film that on the arcade screen if you look at the video posted above in a the real you will notice this shows kinda like this as well it kinda authentic

grant2258

that green box is visible with no artwork added check for yourself

Riverstorm

Ok, sounds good, if it's in the original then I guess it's good.

UDb23

@grant2258 Sorry to say but I don’t think that the polyester stripe should be visible. Screen had tinted stripes but you would not notice them. I played that game a lot as a kid and remember well. Also I never noticed that stripe in any previous mame implementation. If you check the screenshot of the video I posted previously you can see green but no stripe.
Here’s another video of the cab and I can’t see the stripes.

grant2258

there is more than one video of the game if go in really close you can se ethe contrast and shafing in green of the film. You can make it back and white if you want or change the games artwork code. The green film mirrored on the monitor will show something. you can leave it the way it was without alpha blending or work the gfx to blend better either way its up to yourself

grant2258

the original mr do invaders uses a tint mask

UDb23

@grant2258 yes and the newer .lay format uses tinted boxes generated in the layout settings in the .lay itself (no more need for images).
SI colors implementation was discussed long time ago:
https://retropie.org.uk/forum/topic/2042/space-invaders-colors/18

My coding capabilities do not include C unfortunately so while I can read code I don’t think I I’d be able to write new or change current.
IMHO would suggest we make it like the current mame as much as possible (colors but no visible stripe).
You and @markwkidd are already doing so much for this project in coding that I don’t want to give you additional stuff to do. So up to you and what you like best about the colors implementation in SI.

UDb23

@Riverstorm
Could you kindly share your latest Space Invaders .art file content (for 1080p) ?

Riverstorm

I agree I do like it better without the visible strip if it's easy to code but if not then I can live with it too.

Riverstorm

@UDb23 - Here's what I've been running for SI on 1080p.

backdrop:
	file		= moonR.png
	layer		= backdrop
	alpha		= 0.3
	priority	= -2
	visible		= 1
	position	= 0,-0.57142,1,1.57142

grant2258

no code changes using invaders original art from mr do

alt text

UDb23

@grant2258 ...but somewhat transparent in the green... again :-(

grant2258

well you dont want the free tinge or the alpha. We could just make the game b & w. if this is doing the same thing in advance mame is not a code fault on out end ill get it and test it on there at some point and do some experimentation the geen and red added are treated as overlays

Riverstorm

I guess I don't doubt the validity of whether it was there or not but since we are kind of breaking all the rules so to speak for backdrops why not remove it, if it's easy. It's so pronounced when you see it on a TV and doesn't look right to me at all.

grant2258