Hello. I copy/paste it from private message to posila.
Sent: Sun Dec 27, 2015 9:33 pm
It checked at 0.12.24... Bugs is still there.
3 points to bug fixing:
1) railgun shooting without damage 0.12.10-0.12.21 (fixed 0.12.22)
2) impact damage is have 1 type of damage: when entitydied. It bug was in 0.11, it still has in 0.12.22 (fixed 0.12.23).
3-8) improve metod gun_shooting. Oh.. it have very mach of issues.
1) (fixed 0.12.22) no comments.
2) (fixed 0.12.23) if car (or tank) damaging last 1 hitpoint of entity, car take 100% damage of max hitpoints of it entity.
Vanilla game have not entity with so high HP, but in mods some entity have 20k+ HP. It's realy important.
I think it is bug: Create stone-rock with 1/200 hp, crash it at tank, and tank (with resistance "impact" decrease = 50, percent = 60) will take 60 damage = (200-50)*(100-60)/100, where 200 is max_HP of stone-rock. Car (with resistance "impact" decrease = 30, percent = 30) will take 119 damage = (200-30)*(100-30)/100. Now take same tank and new entity with 1/20000 hp... Tank will impact still 1 hp and take 7980 damage.
3) Shotgun shooting do not create "explosion-gunshot" now. "source_effects" do not working in "ammo_type". If paste it to "action_delivery" it will work. But it will repeat 12-16 time (vanilla sotgun and combat-shotgun).
4) End of projectiles is shifted up at 1. Is it have some property to shift it? OK, I can shift down animation and shift up projectile_center. But start.point of bullet_collision will sift up too (I think so). Maybe you will use it for shotguns and shells. It is not working for explosions with "beam = true" (for example "railgun-beam"): If paste shift in their animations, it will be invisible. This problem in all weapons, but have resolved report for Flamethrower https://forums.factorio.com/forum/vie ... 30&t=18361
5) I use "direction_only = false" in projectiles. Items "gun" have "projectile_creation_distance" (PCD). If PCD =0, then target.point is correct (coincides with cursor.point). If PCD = 1, then range increased at 1. It means target.point is shifted at 1 (does not coincide with cursor.point). If PCD = 2, then range increased at 2 etc.
6) Enother problem, when PCD > 0. If cursor stay in area PCD, shooting can turn 360 without turn player. Save "test_weapons.zip" created 27.02.2016 for factorio_0.12.24 can explain issue #6.
7) Items "gun" have property "range". It will do nothing if projectiles have "direction_only" (true or false - no matter).
8) Deviations working at "ammo" (direction_deviation, range_deviation, speed_deviation) it is great, rly. But "gun" have not deviations. If I want to create weapons with 1 type ammo, it will have same deviations.
I can explain some points, if you need it.
[0.12.24] [posila] shooting and damage
Re: [0.12.24] [Michal] shooting and damage
Hi, I appologize for silent treatment from our side 
Our main concern now is to make vanilla 0.12 as stable as possible, so we will revisit your list in 0.13. I cannot promis everything will be changed as you suggested.
#4) Projectiles are drawn shifted up by 1 and projectile shadow is shifted right by 1 in order to create illusion of "flying" on over the ground. This value is hardcoded and currently cannot be changed in prototypes.
EDIT:
#4) I forgot to mention that collision box for projectiles is on "ground level", only sprite is shifted up.
#5) If you want to shoot on cursor, then using target_type = "position" in ammo type and direction_only=false in projectile should do the job. direction_only = true stretches collision box so that projectile cannot fly "through" entities when it has very large speed. direction_only = false causes projectile to be destroyed and invoke its triggers when it gets close enought to target position (which should be cursor position, if you use target_type = "position")
#7) "range" is not property of gun but of attack_parameters which are common to all things that attack. Range in attack parameters is used mainly by things that attack automatically (capsules and turrets) when searching for enemy to attack. For player it is used when target type is "position" or "entity" to disable shooting when cursor is out of range. So problem was not direction_only, it was target_type = "direction" in ammo type.
Our main concern now is to make vanilla 0.12 as stable as possible, so we will revisit your list in 0.13. I cannot promis everything will be changed as you suggested.
#4) Projectiles are drawn shifted up by 1 and projectile shadow is shifted right by 1 in order to create illusion of "flying" on over the ground. This value is hardcoded and currently cannot be changed in prototypes.
EDIT:
#4) I forgot to mention that collision box for projectiles is on "ground level", only sprite is shifted up.
#5) If you want to shoot on cursor, then using target_type = "position" in ammo type and direction_only=false in projectile should do the job. direction_only = true stretches collision box so that projectile cannot fly "through" entities when it has very large speed. direction_only = false causes projectile to be destroyed and invoke its triggers when it gets close enought to target position (which should be cursor position, if you use target_type = "position")
#7) "range" is not property of gun but of attack_parameters which are common to all things that attack. Range in attack parameters is used mainly by things that attack automatically (capsules and turrets) when searching for enemy to attack. For player it is used when target type is "position" or "entity" to disable shooting when cursor is out of range. So problem was not direction_only, it was target_type = "direction" in ammo type.
Re: [0.12.24] [posila] shooting and damage
Hello again,
so #3 was fixed sometime in 0.13
#6, For 0.15, I fixed it for old flamethrower trigger and line action trigger used by railgun. I didn't see this issue on other weapons.
#8 We decided against adding deviations onto guns for time being.
so #3 was fixed sometime in 0.13
#6, For 0.15, I fixed it for old flamethrower trigger and line action trigger used by railgun. I didn't see this issue on other weapons.
#8 We decided against adding deviations onto guns for time being.