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Mortar Accuracy

@Trivia Vanille, absolutely agreed. A trench and HESCO blocks and the sort providing cover makes sense vs a mortar. Unfortunately, the game merely has a single variable for cover percentage. There is not a distinction between overhead cover and other cover.

In vanilla, the cover percentage causes the mortar shot to be more inaccurate which makes no practical sense. Why would the target being behind a tree cause the mortar shot to land elsewhere? Land where it was going to land, just deal less damage.

I don't know if cover affects the blast damage of the shot.

Of course, as mortars are indirect-fire artillery, the shell wouldn't be coming in from a shallow angle either, so low cover like sandbags, single HESCO blocks, or Jersey walls would barely affect the shot at all (but still could catch the shell if the shot wasn't spot-on). However, high cover like a tree trunk, a full-sized wall, or HESCO stack could effectively block any mortar shot fired at the target behind the cover, depending on the velocity of the shell, the material and thickness of the cover, and the type of explosive and fuse in the shell. There's probably a ton of other variables to consider, I'm not an expert by any means, just thought I should mention it since you brought it up in the description... just kinda figure Tynan was probably going for a bit of realism there when he made the formula for it

Hey, just wanted to point out that your target being behind cover would actually affect your shot IRL. It entirely depends on the angle at which the shell comes down from above the target; the steeper the trajectory, the less cover would affect the shot (unless that cover also includes overhead cover, like a roof or, as you mentioned, a tree; I don't believe that the trees in Ribworld actually count as overhead cover, mechanically, although it would be interesting to see if that could potentially be modded in), but the closer your target would have to be. To fully ignore cover, the shell would have to drop pretty much straight down on their head, which would require them to be close enough to the launcher as to make it impossible to actually hit them without destroying the launcher in the process (and by the time the shell landed, the target would have killed the entire mortar team, so there are plenty of more practical ways to accomplish the same goal).

@Astro I mean it doesn't cause any issues. This mod doesn't really affect the automortars since pawns aren't firing them.

works with VFE mechanoids automortars right?

Thank you!

@Hob Took:

Got it, thanks for the explanation!

I see Rimworld 1.5 has the verb property "forcedMissEvenDispersal" which selects a random angle and radius weighted by a golden ratio to produce an even distribution across all the targeted cells.

BUT, this isn't enabled on the mortar ha

@pepsigamer02 In vanilla, after rolling for a random cell to target, if the random cell happens to be the cell we wanted to target (the exact center) then cover is applied and we roll to see if the shot misses due to cover.

In modded, cover has no affect on mortar shots. We merely are determining a random angle + radius to target then let it fire.


As to why the Q&A doesn't talk about sight and manipulation, Rimworld keeps changing how mortar accuracy is calculated and I haven't bothered to keep the Q&A up to date with the sight, manipulation, mortar barrel, difficulty setting, and Rimwold version differences.

(skill multiplier) is a 0->2 range multiplier. If we use the mod default values of maximum skill = 75% miss reduction and no skill = -40% miss reduction, these would be the miss values:

Base mortar miss radius = 13 (assuming no weather multiplier)
Colonist with avg skill 0 = 40% increase in radius, 18.2
Colonist with avg skill 10 = 57.5% reduction (halfway between -40% and +75%), 5.525
Colonist with avg skill 20 = 75% reduction, 3.25