feat(engine): Add Spring Constraint

engine/CMakeLists.txt

@@ -109,8 +109,10 @@ set(CUBOS_ENGINE_SOURCE
 	"src/physics/solver/plugin.cpp"
 	"src/physics/constraints/penetration_constraint.cpp"
 	"src/physics/constraints/distance_constraint.cpp"
+    "src/physics/constraints/spring_constraint.cpp"
 	"src/physics/solver/penetration_constraint/plugin.cpp"
 	"src/physics/solver/distance_constraint/plugin.cpp"
+    "src/physics/solver/spring_constraint/plugin.cpp"
 	"src/physics/fixed_substep/plugin.cpp"
 	"src/physics/fixed_substep/substeps.cpp"
 	"src/physics/solver/integration/plugin.cpp"

engine/include/cubos/engine/physics/constraints/spring_constraint.hpp

@@ -0,0 +1,27 @@
+/// @file
+/// @brief Component @ref cubos::engine::SpringConstraint.
+/// @ingroup physics-solver-plugin
+
+#pragma once
+
+#include <vector>
+
+#include <glm/vec3.hpp>
+
+#include <cubos/core/ecs/entity/entity.hpp>
+#include <cubos/core/reflection/reflect.hpp>
+
+namespace cubos::engine
+{
+    /// @brief Relation which holds the information for a spring constraint between two bodies.
+    /// @ingroup physics-solver-plugin
+    struct SpringConstraint
+    {
+        CUBOS_REFLECT;
+        float stiffness;        ///< Spring stiffness (force per unit extension)
+        float damping;          ///< Damping coefficient
+        float restLength;       ///< Rest length of spring
+        glm::vec3 localAnchor1; ///< The local contact point relative to the center of mass of the first body.
+        glm::vec3 localAnchor2; ///< The local contact point relative to the center of mass of the second body.
+    };
+} // namespace cubos::engine

engine/samples/CMakeLists.txt

@@ -30,6 +30,7 @@ function(make_sample)
     target_link_libraries(${target} cubos::engine)
     cubos_common_target_options(${target})
 
+
     if(EMSCRIPTEN)
       target_link_options(${target} PRIVATE
         "SHELL:--shell-file ${CMAKE_CURRENT_SOURCE_DIR}/emscripten.html"
@@ -77,4 +78,5 @@ make_sample(DIR "ui" ASSETS)
 make_sample(DIR "physics" ASSETS)
 make_sample(DIR "complex_physics" ASSETS)
 make_sample(DIR "distance_constraint" ASSETS)
+make_sample(DIR "spring_constraint" ASSETS)
 make_sample(DIR "games/cubosurfers" ASSETS SOURCES "spawner.cpp" "obstacle.cpp" "player.cpp")

engine/samples/distance_constraint/main.cpp

@@ -16,6 +16,7 @@
 #include <cubos/engine/gizmos/target.hpp>
 #include <cubos/engine/input/plugin.hpp>
 #include <cubos/engine/physics/constraints/distance_constraint.hpp>
+#include <cubos/engine/physics/constraints/spring_constraint.hpp>
 #include <cubos/engine/physics/plugin.hpp>
 #include <cubos/engine/physics/solver/plugin.hpp>
 #include <cubos/engine/render/camera/camera.hpp>
@@ -48,9 +49,10 @@ struct Options
         Circle,
         Pendulum,
         DoublePendulum,
-        PushPull
+        PushPull,
+        SpringTest
     };
-    Scenarios currentScenario = DoublePendulum;
+    Scenarios currentScenario = Circle;
 };
 
 struct State
@@ -288,7 +290,7 @@ int main(int argc, char** argv)
                 glm::vec3 direction =
                     glm::normalize(glm::vec3(localToWorld2.mat * glm::vec4(constraint.localAnchor2, 1.0F)) - pointFrom);
 
-                gizmos.color({1.0F, 0.0F, 0.0F});
+                gizmos.color({0.0F, 1.0F, 1.0F});
                 gizmos.drawLine("the line between", pointFrom,
                                 constraint.isRigid ? pointFrom + glm::normalize(direction) * constraint.fixedDistance
                                                    : pointFrom + glm::normalize(direction) * constraint.minDistance);
@@ -345,6 +347,9 @@ int main(int argc, char** argv)
                 options.currentScenario = Options::Scenarios::PushPull;
                 break;
             case Options::Scenarios::PushPull:
+                options.currentScenario = Options::Scenarios::SpringTest;
+                break;
+            case Options::Scenarios::SpringTest:
                 options.currentScenario = Options::Scenarios::Circle;
                 break;
             }

engine/samples/spring_constraint/assets/collisions.bind

@@ -0,0 +1,44 @@
+{
+    "actions": {
+        "camera-toggle": [
+            {"keys": ["LControl"]}
+        ],
+        "reset": [
+            {"keys": ["Space"]}
+        ]
+    },
+    "axes": {
+        "move-lateral": {
+            "positive": [
+                {"keys": ["D"]}
+            ],
+            "negative": [
+                {"keys": ["A"]}
+            ]
+        },
+        "move-vertical": {
+            "positive": [
+                {"keys": ["E"]}
+            ],
+            "negative": [
+                {"keys": ["Q"]}
+            ]
+        },
+        "move-longitudinal": {
+            "positive": [
+                {"keys": ["W"]}
+            ],
+            "negative": [
+                {"keys": ["S"]}
+            ]
+        },
+        "change-speed": {
+            "positive": [
+                {"keys": ["Tab"]}
+            ],
+            "negative": [
+                {"keys": ["LShift"]}
+            ]
+        }
+    }
+}

engine/samples/spring_constraint/assets/collisions.bind.meta

@@ -0,0 +1,3 @@
+{
+    "id": "53d85d6f-42a8-4eb8-aeae-1754a4cb20df"
+}