add 'mass' and 'elasticity' entity properties

src/objects/Entities.cpp

@@ -22,6 +22,7 @@
 
 #include <entt/entity/registry.hpp>
 #include <glm/ext/matrix_transform.hpp>
+#include <limits>
 #include <sstream>
 
 static debug::Logger logger("entities");
@@ -318,6 +319,9 @@ void Entities::preparePhysics(float delta) {
         if (!eid.def.solid) {
             continue;
         }
+        rigidbody.hitbox.mass = eid.def.bodyType == BodyType::DYNAMIC
+                                    ? eid.def.mass
+                                    : std::numeric_limits<float>::infinity();
         solidHitboxes.emplace_back(&rigidbody.hitbox);
     }
 }

src/objects/EntityDef.cpp

@@ -10,6 +10,8 @@ void EntityDef::cloneTo(EntityDef& dst) {
     dst.skeletonName = skeletonName;
     dst.blocking = blocking;
     dst.solid = solid;
+    dst.mass = mass;
+    dst.elasticity = elasticity;
     dst.stepHeight = stepHeight;
     dst.save = save;
 }

src/objects/EntityDef.hpp

@@ -45,6 +45,12 @@ struct EntityDef {
     /// @brief Is the entity solid (blocks other entities)
     bool solid = false;
 
+    /// @brief Mass for physics calculations
+    float mass = 1.0f;
+
+    /// @brief Elasticity for physics calculations
+    float elasticity = 0.0f;
+
     /// @brief Max obstacle height that does not require jumping
     float stepHeight = 0.5f;