Reimplement recoil_player and put it to use with a sample assault rifle

[geneotech]

There should be two structures: recoil_player (global scope) Has a vector of recoil impulses and a parameter for the duration it takes the cooldown to descend from one impulse to the previous. Is an asset. Its get_logical_meta(const assets_manager& manager) const shall return the recoil_player itself as a copy. Has a corresponding assets::recoil_player_id defined.

recoil_player_instance (global scope) Keeps data that determines the index of the value to be returned as the next impulse. Has methods like: float shoot_and_get_impulse(const recoil_player& meta); void cooldown(float amount_ms);

If the next impulse is out of bounds, it should return a random value seeded after the current heat.

Add recoil_player_instance and assets::recoil_player_id to components::gun and take use of it in the gun_system.cpp where the force applied upon shot is always in the same direction ( if (total_recoil_amount > 0.f) { ... } ). Hint: the recoil player will be obtained by step.input.metas_of_assets.find. If it returns null pointer (player not found), apply no recoil at all.

Note: this might be easier to tweak once we have the editor GUI. Hint: use minimal_scene.cpp (former name: one_entity.cpp) and debug_minimal_test_scene = true in config for maximum performance in Debug mode.

[geneotech]

physical_material struct follows a very similar schema to recoil_player (regarding assets and ids, though no instances of materials), and is used to generate collision sounds in sound_existence_system::create_sounds_from_game_events

[geneotech]

Updated preferred file locations:

src/game/assets/recoil_player_id.h
src/game/assets/recoil_player.h
src/game/assets/recoil_player.cpp

[DaTa-]

I have following issues which render last task related commit incomplete:

• Where should recoil_player_instance reside? For now, it's inside gun_component.h
• I haven't implemented cooldown since I don't know details of it's usage
• For now, I've added recoil application based on the old code, but I don't know how it should be properly implemented and interact with gun_system code
  • I have no idea how to implement recoil for rigid_body_of_gun and don't know if is there any weapons to test it on, so for now it's untested crippled version of old code
  • Code which applies recoil impulse to CROSSHAIR_RECOIL_BODY is a mess based on the old code, since I didn't understand logic behind it's application by angular_impulse function and not sure what offset of a recoil_player represents in general.
• What should each vec2 offset characterize? I've added some GENERIC recoil player with offset directed backwards relative to X axis, with normally distributed angle in range of [-pi; pi] and with magnitude of 650-850.
• For now, recoil players are "loaded" inside game/hardcoded_content/test_scenes/test_scene_recoil_players.cpp. Location I've chose based on other assets paths. Probably there is better place to do so.
• Something else what I forgot 😁

[geneotech]

• Let recoil_player_instance reside within recoil_player.h.
• recoil_player_instance should have some "heat" variable by which to determine the index of the next recoil to apply. void cooldown(float amount_ms); is supposed to decrease that heat, as if the gun was cooling down.
• gun_system:
  • let rigid_body_of_gun be unconcerned with recoil. Only recoil_body variable (crosshair's recoil body) should be acted upon with recoil_player_instance.
  • yeah, it was a mess, so I would not necessarily base the new functionality on it. About offsets...
• ... you are right, they actually should not be vec2 like it was before, just angular values represented by a float. These should multiply the angular impulse that is applied here:

                        recoil_body.apply_angular_impulse(
                            total_recoil_amount * recoil_body.get_inertia() * 10.f
                        );

And apart from cooldown, that should be all change that's needed in gun_system.cpp.

The signature should be thus: float shoot_and_get_impulse(const recoil_player& meta); (I've just copy-derped the previous one)

The rotation of the character's CROSSHAIR_RECOIL_BODY determines the angle by which to rotate the character itself, which effectively simulates a recoil effect.

• The location is fine.

[geneotech]

The cooldown should also happen in an else to this condition:

            if (
                gun.is_trigger_pressed 
                && has_enough_mana
                && has_enough_physical_bullets
                && gun.shot_cooldown.try_to_fire_and_reset(cosmos.get_timestamp(), delta)
            ) {

[geneotech]

Implementation is complete.