[1.25g] Truck Model Weight/Movement Mod Bug

[Slippy]

There is some missing data in regards to truck model design which I believe came in around 1.21i which makes designing a reasonable truck pretty hard (as well making many model truck designs largely useless).

According to the manual/patch notes:
Trucks (and to lesser extent APC) get some simulated weight in their Movement Cost Modifier calculations so that their eventual cargo is taken into account as well.

This is not taken into account on the design log/model screen. Here is the stats for the truck model in a turn 1 save.

Truck Stats.PNG (181.33 KiB) Viewed 659 times

With an engine strength of 200 modified for the engine roll (200*0.72) this should give a final engine strength of 144, more than double the weight on the design log.

Truck Move Mod.PNG (1.43 MiB) Viewed 659 times

This suggests that is not the case.

In fact to have a truck design using one of the starting engines which is a good as the irregular trucks your militia drive around you need a vastly more powerful truck (unless you roll high on engine design) with either a heavy or double diesel engine. Is this intended behaviour?

[Slippy]

Wanted to add to this as I am also seeing alarming issues with normal vehicle design.

Light Tanks Stats.PNG (182.74 KiB) Viewed 649 times

This gives the formula (300*68%)/460 = which gives a engine power/weight of 44%. Based on the table in the manual I should get get a 50% AP movement cost.

But I actually get a -100%AP modifier

Light Tanks Move Mod.PNG (390.72 KiB) Viewed 649 times

The blueprint for this exact tank also is wrong. The blueprint it was based on is suggesting a +60% AP cost. The blueprint is using an engine design score of 86 which should give the following:
(300*86%)/460 = 56% which suggests a 40% movement modifier based on the table.

Either something is very wrong or I have the wrong calculation or the table in the manual in wrong. Either way - designing vehicles right now is largely pointless as I cannot make sense of the system with the tools I have been given.

[Slippy]

I did some further testing based on blue print models and actual produced models. This all based on no extra applied techs, just basic early game stuff. I am ignoring trucks for now because without knowing the 'hidden weight' its a pointless exercise.

Model Engine Calc 1.PNG (17.29 KiB) Viewed 616 times

Something very wacky is going on. Even if I ignore the manual table we have situations where a engine power/weight ratio of 60% produces a +60% move mod on a buggy but a 63% ratio on a light tank produces a +40% move mod. I think the most concerning thing is that a ratio difference on a blueprint of a light tank with a ratio of 38% vs 34% produced a +100% and +120% despite only being a negligible difference.

Probably some calculations have changed and arent being reflected in the design log (maybe I am missing some weight calculations) but some clarity on how it all works would be good.

[Vic]

I guess i have to update that table in the manual. In fact is AP cost for movement goes up above normal the effect is multiplied by 2. This is a relatively recent change.

Also note that the effects are not linear but discrete.

And also note that Blue Print always uses Engine Design 100%. I am adding this to the design log in blue prints in the upcoming version.

Thanks for posting!

[Slippy]

I guess i have to update that table in the manual. In fact is AP cost for movement goes up above normal the effect is multiplied by 2. This is a relatively recent change.

Also note that the effects are not linear but discrete.

And also note that Blue Print always uses Engine Design 100%. I am adding this to the design log in blue prints in the upcoming version.

Thanks for posting!

Thanks for confirming Vic! Having the new table will help a lot I think and thank you for explaining the effects are discrete not linear. I ran through my table using your updated info and the calculations were a lot closer based on the info you gave.
When you update the manual would it be possible to include how the 'extra weight' for trucks/APCs are calculated as well? Just for completeness if we want to run our own calculations for model design.

[Vic]

New manual might be a few months off as I do that only with big updates, but yes i will.

FYI
Truck +140 simulated weight, APC +70 simulated weight in the weight:engine ratio calculations.

[Slippy]

New manual might be a few months off as I do that only with big updates, but yes i will.

FYI
Truck +140 simulated weight, APC +70 simulated weight in the weight:engine ratio calculations.

Great! Of course and thank you again for the reply and extra data