HOWTO: Use MAME Shaders

dugan · 08-02-2015, 10:56 PM

Note: if you see people online talking about "SDLMAME", that's just MAME.

Anyway, I finally got around to trying MAME with shaders. I did this on Slackware64 14.1, using MAME 0.160. The paths I'm going to describe are correct for it, and should be correct for other distros too.

First, I created a user-level MAME directory and made a copy of the global MAME ini file:

Code:

mkdir -p ~/.mame
cp /etc/mame.ini ~/.mame

I downloaded the "shader pack" from the GLSL SHADERS SETUP (MAME/MESS) page, then unzipped it into my MAME directory:

Code:

~/.mame
tar xfv ~/Downloads/mame_glsl_osd.tar.gz

That pack comes with a CRT-geom shader. Here are the changes I then made to my mame.ini to get it activated:

Code:

waitvsync 1
glsl_shader_mame0 /home/dugan/.mame/osd/shader/glsl_plain
glsl_shader_mame1 /home/dugan/.mame/osd/CRT-geom

I know the paths work if they are absolute and have no environment variables or tildes.

You can't miss the CRT-geom shader if it's working. It makes your screen deformed as if it were the surface or a fish bowl, or like a particularly round CRT.

If you look in ~/.mame/osd, you'll see the following files:

CRT-geom.vsh
CRT-geom_idx16_lut.fsh
CRT-geom_rgb32_dir.fsh
CRT-geom_rgb32_lut.fsh

Relate that to the value of "glsl_shader_mame1" in mame.ini, and it should be pretty clear how to install and activate other shaders.

One particularly popular shader is a CRT shader called "Lottes". I downloaded it and unzipped it in ~/.mame. That put all its *.?sh files in ~/.mame/shader, so I activated it by setting the appropriate key in mame.ini:

Code:

glsl_shader_mame1 /home/dugan/.mame/shader/Lottes_CRT

SABR was one I was particular looking forward to running. It's a variation on xBR, which is an improvement on the HQnx scalers, which were in turn an improvement on SuperEagle, 2xSAI and those others ones. I already had Lottes in ~/.mame/shader, so I put all of SABR's *.?sh files in the same directory. Then I just activated it:

Code:

glsl_shader_mame1 /home/dugan/.mame/shader/sabr

So once it's set up, changing shaders is just a matter of changing one line in mame.ini.

dugan · 09-22-2016, 11:04 PM

The above is still correct if you want to use the (Timothy) Lottes shader, but MAME now comes with shaders built-in.

To use them:

1. copy the artwork/ and bgfx/ directories from the MAME source archive to ~/.mame

2. set the following in ~/.mame/mame.ini:

Code:

bgfx_path /absolute/path/to/.mame/bgfx
video bgfx

3. Start a game and press tilde to bring a menu. Press Down until you get to Effect and press Left and Right to change to either crt-geom-deluxe or super-eagle

4. If you chose crt-geom-deluxe (which I recommend), go back to the tilde menu and keep pressing down to set shader options such as the curvature, etc

dugan · 03-25-2017, 03:44 PM

This is what I'll be using for the foreseeable future:

1. have a ~/.mame/bgfx tree (so that I can edit the shaders)

2. have the following in ~/.mame/mame.ini:

Code:

# Smaller viewport, but evenly-sized pixels
unevenstretch             0

# This seems to still need paths with no tildes or dollar signs
bgfx_path                 /home/dugan/.mame/bgfx

bgfx_screen_chains        crt-geom-deluxe

3. Edit ~/.mame/bgfx/chains/crt-geom-deluxe.json

and change:

Code:

{
    "type": "float",
    "name": "curvature",
    "text": "Enable curvature",
    "default":  1.0,

to:

Code:

{
    "type": "float",
    "name": "curvature",
    "text": "Enable curvature",
    "default":  0.0,

to disable the curvature effect