| Option Category | # # DIRECT3D POST-PROCESSING OPTIONS # |
| Description | This option sets the horizontal offset for the shadow mask created from the original shadow mask image, measured as a percentage from the top left corner. |
| Full Command | -shadow_mask_usize <float> |
| Alt. Command | none |
| Reverse Command | none |
| Example | mame64 pacman -hlsl_enable -shadow_mask_image shadow-mask.png -shadow_mask_uoffset 0.5 |
| mame.ini Command | shadow_mask_usize |
| Command Default | 0.1875 |
| Argument Format | <float> |