Training dummy leans with knockback, blast pushes, Vacuum suction and gusts

Hits tip it by their actual knockback (shared with fighters through knock_get), blasts push it, a Vacuum pulls it
toward its wielder and an airblast shoves it away. Blocks stay still. Protocol 7.

src/fighter.cpp

@@ -127,6 +127,15 @@ void Fighter::state_reset(Sim& sim, float maxHealth)
     isAlive = true;
 }
 
+// The knock a hit gives whatever it lands on, centred at center: away from where it came from (and a little upward), at
+// a speed that grows with the damage, times the hit's own knock.
+Vec2 knock_get(Damage& damage, Vec2 center)
+{
+    Vec2 away = center - damage.source;
+    Vec2 direction = vec2_normalize(vec2_normalize(vec2_length(away) > 1 ? away : Vec2{0, -1}) + Vec2{0, -KNOCK_LIFT});
+    return direction * std::min(KNOCK_MAX, KNOCK_BASE + damage.amount * KNOCK_PER_DAMAGE) * damage.knock;
+}
+
 // Loses health with a flash and hitstop, and gets knocked away from where the hit came from (and a little upward),
 // up to a speed that grows with the damage (see knock_take). Shock Absorber softens it. Running out of health kills it
 // in a burst, and its attacks vanish with it.
@@ -138,11 +147,8 @@ void Fighter::damage_take(Sim& sim, Damage damage)
     flash = 1;
     hitstop_add(damage.hitstop);
 
-    Vec2 away = center_get() - damage.source;
-    Vec2 direction = vec2_normalize(vec2_normalize(vec2_length(away) > 1 ? away : Vec2{0, -1}) + Vec2{0, -KNOCK_LIFT});
-    float knock = std::min(KNOCK_MAX, KNOCK_BASE + damage.amount * KNOCK_PER_DAMAGE) * damage.knock *
-                  (isRacing ? RACE_KNOCK : 1) * stat_get(STAT_KNOCKBACK_TAKEN);
-    knock_take(direction * knock, damage.owner);
+    float taken = (isRacing ? RACE_KNOCK : 1) * stat_get(STAT_KNOCKBACK_TAKEN);
+    knock_take(knock_get(damage, center_get()) * taken, damage.owner);
     if (health > 0)
         return;
     die(sim);

src/fighter.h

@@ -98,6 +98,9 @@ constexpr float CHARGE_VISIBLE = 0.15f;
 // knock it about (half as hard), and touching a pit puts it back on the last ground it stood squarely on. Slopes slow
 // it climbing and speed it up descending. Crouching on one slides it down, rolling, and the slide carries on over flat
 // ground until it slows.
+struct Damage;
+Vec2 knock_get(Damage& damage, Vec2 center);
+
 class Fighter
 {
     friend class Scene;

src/protocol.h

@@ -27,7 +27,7 @@
 #include <string_view>
 #include <type_traits>
 
-constexpr int PROTOCOL_VERSION = 6;
+constexpr int PROTOCOL_VERSION = 7;
 constexpr int LOBBY_MEMBERS_MAX = 16;
 constexpr int LOBBY_CODE_LENGTH = 4;
 // Letters only, without I and O, so codes are easy to read out and type.

src/weapon.cpp

@@ -85,7 +85,10 @@ constexpr float WHIP_WOBBLES = 1;
 constexpr float WHIP_DAMPING = 0.02f;
 constexpr float WHIP_SAG = 0.6f;
 constexpr float WHIP_PULL = 220;
-constexpr float WOBBLE_IMPULSE = 0.15f;
+// How far a push tips a dummy: its sideways speed into lean speed for a sudden push (a hit or a blast), and its
+// sideways acceleration into lean acceleration for a steady one (a Vacuum's pull).
+constexpr float WOBBLE_PER_SPEED = 0.005f;
+constexpr float WOBBLE_PER_PULL = 0.05f;
 // Vacuum: how fast its pull speeds fighters and shots up toward it, how much of an airblast's knock is left at the edge
 // of its reach, and how much of it shoves shots.
 constexpr float VACUUM_PULL_RATE = 900;
@@ -1607,6 +1610,14 @@ void Weapons::attack_hit(Sim& sim, Attack& attack, int target, Vec2 point)
                 });
 }
 
+// Tips a dummy the way a sudden push goes (a block, which never leans, ignores it), by its sideways part: a dummy
+// stands on its stand, so only its lean feels the push.
+static void dummy_push(Dummy& dummy, Vec2 push)
+{
+    if (dummy.tile < 0)
+        dummy.wobbleSpeed += push.x * WOBBLE_PER_SPEED;
+}
+
 // Hurts a target with all the feedback: sparks, a number, shake that grows with the damage and a sound. The attacker
 // freezes in hitstop, its Boxing Glove adds to the knock, and its Embiggener to the damage.
 // Dummies flash and wobble, blocks crack and break, and fighters take the damage themselves. In a race, fighters only
@@ -1627,7 +1638,7 @@ void Weapons::damage_deal(Sim& sim, Damage damage)
     {
         Dummy& dummy = sim.world.dummies[damage.target - MAX_FIGHTERS];
         dummy.flash = 1;
-        dummy.wobbleSpeed += side * WOBBLE_IMPULSE * damage.amount;
+        dummy_push(dummy, knock_get(damage, {box.x + box.w / 2, box.y + box.h / 2}));
         dummy.health -= damage.amount;
         if (dummy.tile >= 0 && dummy.health <= 0)
             sim.world.block_break(sim, dummy, damage.owner);
@@ -2052,6 +2063,13 @@ void Weapons::blast_spawn(Sim& sim, Blast blast)
             vec2_normalize(distance > 0 ? away : Vec2{0, -1}) * KNOCKBACK_SPEED * (1 - distance / reach) * absorb;
         fighter.impulse_add(push);
     }
+    for (Dummy& dummy : sim.world.dummies)
+    {
+        Vec2 away = Vec2{dummy.box.x + dummy.box.w / 2, dummy.box.y + dummy.box.h / 2} - blast.position;
+        float distance = vec2_length(away);
+        if (blast.isPushing && distance < reach)
+            dummy_push(dummy, vec2_normalize(away) * KNOCKBACK_SPEED * (1 - distance / reach) * boxing);
+    }
 
     Attack attack = {
         .stats = {.damage = blast.damage, .range = blast.area},
@@ -2283,6 +2301,15 @@ void Weapons::vacuum_move(Sim& sim, Attack& attack)
         float pull = std::min(room, VACUUM_PULL_RATE * boxing * TICK) * target.stat_get(STAT_KNOCKBACK_TAKEN);
         target.body.velocity = target.body.velocity + toward * pull;
     }
+    for (int i = 0; i < (int)sim.world.dummies.size(); i++)
+    {
+        Dummy& dummy = sim.world.dummies[i];
+        Vec2 center = {dummy.box.x + dummy.box.w / 2, dummy.box.y + dummy.box.h / 2};
+        if (dummy.tile >= 0 || !is_target(sim, MAX_FIGHTERS + i, attack.owner) || !is_in_cone(attack, center))
+            continue;
+        Vec2 toward = vec2_normalize(attack.position - center);
+        dummy.wobbleSpeed += toward.x * VACUUM_PULL_RATE * fighter.stat_get(STAT_KNOCKBACK) * WOBBLE_PER_PULL * TICK;
+    }
     // Each interval (the hit cooldown counting it down), everyone in the cone can be nibbled again.
     float interval = fighter.level_get(attack.key).cooldown / fighter.stat_get(STAT_ATTACK_RATE);
     bool isPulse = attack.hitCooldown <= 0;
@@ -2323,13 +2350,16 @@ void Weapons::gust_move(Sim& sim, Attack& attack)
         if (!is_target(sim, target, attack.owner) || !is_in_cone(attack, center))
             continue;
         attack_hit(sim, attack, target, center);
-        if (target >= MAX_FIGHTERS)
-            continue;
         // Boxing Glove adds to it as to any knock.
+        Vec2 push = vec2_normalize(center - attack.position) * attack.stats.speed * cone_strength_get(attack, center) *
+                    sim.fighters[attack.owner].stat_get(STAT_KNOCKBACK);
+        if (target >= MAX_FIGHTERS)
+        {
+            dummy_push(sim.world.dummies[target - MAX_FIGHTERS], push);
+            continue;
+        }
         Fighter& fighter = sim.fighters[target];
-        float strength = attack.stats.speed * cone_strength_get(attack, center) *
-                         fighter.stat_get(STAT_KNOCKBACK_TAKEN) * sim.fighters[attack.owner].stat_get(STAT_KNOCKBACK);
-        fighter.knock_take(vec2_normalize(center - attack.position) * strength, attack.owner);
+        fighter.knock_take(push * fighter.stat_get(STAT_KNOCKBACK_TAKEN), attack.owner);
     }
     shots_drift(sim, attack, attack.stats.speed * GUST_SHOT_SHARE, 0, attack.isCopy ? 0 : GUST_RESTORE);
 }