feat(doom): Add haptic support to doom

* Update doom to have callbacks for when the player is damaged and when they fire a weapon
* Update doom implementation to trigger different haptic effects depending on the weapon fired and the amount of damage taken

Haptics are awesome, and with doom we have the actual source code so we can do some fun stuff :)

Build and run `main` on Box-Emu v0 which has haptics and ensure it feels good.

Author: finger563

components/doom/prboom/p_inter.c

@@ -808,9 +808,10 @@ void P_DamageMobj(mobj_t *target,mobj_t *inflictor, mobj_t *source, int damage)
           (player->cheats&CF_GODMODE || player->powers[pw_invulnerability]))
         return;
 
+      int saved = 0;
       if (player->armortype)
         {
-          int saved = player->armortype == 1 ? damage/3 : damage/2;
+          saved = player->armortype == 1 ? damage/3 : damage/2;
           if (player->armorpoints <= saved)
             {
               // armor is used up
@@ -825,6 +826,14 @@ void P_DamageMobj(mobj_t *target,mobj_t *inflictor, mobj_t *source, int damage)
       if (player->health < 0)
         player->health = 0;
 
+      // [WILLIAM]: trigger haptic effect for the player getting injured based
+      //            on the amount of damage received (armor/base). Use damage
+      //            (hits to health) and saved (hits to armor) to determine.
+      //
+      // printf("Player %d took %d damage (%d saved)\n",
+      //        player - players, damage, saved);
+      R_PlayerHurt(player, damage, saved);
+
       player->attacker = source;
       player->damagecount += damage;  // add damage after armor / invuln
 

components/doom/prboom/p_pspr.c

@@ -282,6 +282,12 @@ static void P_FireWeapon(player_t *player)
   newstate = weaponinfo[player->readyweapon].atkstate;
   P_SetPsprite(player, ps_weapon, newstate);
   P_NoiseAlert(player->mo, player->mo);
+  // [WILLIAM]: trigger haptic effect for firing the weapon based on the
+  //            weaponinfo[player->readyweapon]. player->readyweapon is the
+  //            weapon enum (e.g. 0 is fist, 1 is gun, 2 is shotgun, etc.).
+  //
+  // printf("P_FireWeapon: %d\n", player->readyweapon);
+  R_PlayerFire(player);
 }
 
 //

components/doom/prboom/r_main.h

@@ -117,4 +117,21 @@ void R_Init(void);                           // Called by startup code.
 void R_SetViewSize(int blocks);              // Called by M_Responder.
 void R_ExecuteSetViewSize(void);             // cph - called by D_Display to complete a view resize
 
+//
+// HAPTICS - functions to call for various events that should trigger haptics
+//
+
+// called when the player fires a weapon, can get player->readyweapon to know
+// which weapon to use for the haptic feedback
+void R_PlayerFire(player_t *player);
+
+// called when the player picks up a weapon, can get player->readyweapon to know
+// which weapon
+void R_PlayerPickupWeapon(player_t *player);
+
+// called when the player is hurt. damage is the amount of health lost, saved is
+// the amount of health saved by armor (which is the same as the amount of armor
+// lost)
+void R_PlayerHurt(player_t *player, int damage, int saved);
+
 #endif

components/doom/src/doom.cpp

@@ -96,6 +96,41 @@ extern "C" {
         {(int)GamepadState::Button::Y, &key_weapontoggle},
     };
 
+    void R_PlayerFire(player_t *player) {
+        static auto& box = BoxEmu::get();
+        int haptic_effect_index = 0;
+        int weapon_fired = player->readyweapon;
+        if (weapon_fired == wp_fist) {
+            haptic_effect_index = 3;
+        } else if (weapon_fired == wp_pistol) {
+            haptic_effect_index = 2;
+        } else if (weapon_fired == wp_shotgun) {
+            haptic_effect_index = 10;
+        } else if (weapon_fired == wp_chaingun) {
+            haptic_effect_index = 12;
+        } else if (weapon_fired == wp_missile) {
+            haptic_effect_index = 27;
+        } else if (weapon_fired == wp_plasma) {
+            haptic_effect_index = 14;
+        } else if (weapon_fired == wp_bfg) {
+            haptic_effect_index = 47;
+        } else if (weapon_fired == wp_supershotgun) {
+            haptic_effect_index = 52;
+        }
+        box.play_haptic_effect(haptic_effect_index);
+    }
+
+    void R_PlayerHurt(player_t *player, int damage, int saved) {
+        static auto& box = BoxEmu::get();
+        int haptic_effect_index = 0;
+        if (damage > 5) {
+            haptic_effect_index = saved > 0 ? 70 : 75;
+        } else if (damage > 0) {
+            haptic_effect_index = saved > 0 ? 78 : 64;
+        }
+        box.play_haptic_effect(haptic_effect_index);
+    }
+
     void I_StartFrame(void) {
     }
 

components/gui/include/gui.hpp

@@ -103,6 +103,10 @@ class Gui {
     paused_ = false;
   }
 
+  int get_haptic_waveform() const {
+    return haptic_waveform_;
+  }
+
   void set_haptic_waveform(int new_waveform) {
     if (new_waveform > 123) {
       new_waveform = 1;

main/main.cpp

@@ -88,6 +88,7 @@ extern "C" void app_main(void) {
     }
 
     // have broken out of the loop, let the user know we're processing...
+    emu.set_haptic_effect(gui.get_haptic_waveform());
     emu.play_haptic_effect();
 
     gui.pause();