here's what I've studied from this single-player
campaign clip & what elements in the HUD refer to.
here's the link: www.youtube.com/watch?v=zsoDh6TIKDo
also, a snapshot is provided. without any delay,
here's what I've discovered.
Blue & green meters on the left: Blue = health, green = armor.
Blue, green & red meters on right: Blue = ammo, red = chainsaw usage, green = BFG 9000.
the 3 item slots on the right side of the HUD corresponds to the grenades & items
the player can use.
however, when paused or when you enter the sub-menu, you can access
the Praetor suit; aka Doomguy's armor. there are 2 yellow icons on
the top-right of the screen. the triangular yellow icon are weapon
upgrade point while the spherical yellow icon is an a suit upgrade point.
so, if/when Caliber or 0x90 get to play DOOM, here's the following cheats
we'll need:
Inf. health, Inf. Armor, Inf. Ammo, Inf. Grenades/items, Inf. Chainsaw meter,
Inf. BFG meter. Plus, we'll need add weapon points & add suit points too.
another cheat we'll need, another thing...apparently singleplayer uses power-ups
like Quad Damage, Haste & even Berserk. we'll also need an Inf. power-up cheat
just in case one of us feels tempted to become more OP than usual & make
the demon's lives a literal living hell.
Other than that, that's about it.