Specify ground to air transitions and thresholds (#41)

Reviewed-on: #41
Co-authored-by: Álex Román Núñez <eirexe@eirteam.moe>

src/fighter/attack/mod.rs

@@ -43,6 +43,7 @@ pub enum HitReactionKind {
 #[derive(Debug, Hash, Clone)]
 pub struct FighterHitReaction {
     pub launch_velocity: FGVec2,
+    pub launch_angle: FGi32,
     pub hitstop_frames: HitStop,
     pub hitstun_frames: u32,
     pub kind: HitReactionKind,
@@ -62,10 +63,13 @@ pub struct FighterLastAttackDebug {
     pub trajectory_points: Vec<Vec3>,
 }
 
-#[derive(Debug, Default, Clone, Deref, DerefMut, Hash)]
+#[derive(Debug, Default, Clone, Deref, DerefMut, Hash, PartialEq, PartialOrd)]
 pub struct HitStop(u32);
 
 impl HitStop {
+    pub fn new(hitstop: u32) -> Self {
+        HitStop(hitstop)
+    }
     pub fn calculate(attack_damage_stalled: FighterDamage, crouch_cancelling: bool) -> Self {
         let a = (attack_damage_stalled.0 / FGi32::lit("3.0") + FGi32::lit("4.0")).round_to_zero();
         let crouch_cancelling_factor = if crouch_cancelling {