Hi all my first post!!! I am getting some excellent results enabling HLSL via the mame.ini file. If you haven't already done so, edit the mame.ini file to enable the hlsl features ( you will need DirectX 9c - regardless if your using DX11 or 12 - you must install DX9c ) Scroll down to this in mame.ini:
# DIRECT3D POST-PROCESSING OPTIONS
hlsl_enable 1 <---- 1 is enabled, 0 is off
The snape width and height is what I am using with corresponding artwork over lays I made:
I am using these mask counts, some say the y count set at 6 is better for them, but for me its 12 both ways:
Now for cubic distortions and corners, I am using these settings to give the scan lines a slightly curved looked at the corners to look as if the display is wrapping around the curvature of a CRT as they are not perfectly flat screens.
After HLSL is enabled, then you can play with the scan line attributes:
With HLSL enabled you will get a lot of new machine settings. Otherwise if its disabled, you will not see the new settings and not be able to adjust scan lines and other cool features that will allow you to tweak your in game display setup. (slider controls is where you will find all the scan line adjustments) I prefer to use custom artwork and overlays so I can have a true ratio of the original display, see attached.
These scan lines are almost perfect for me...
[ATTACHED IMAGE - CLICK FOR FULL SIZE]