1 files changed, 131 insertions, 0 deletions
diff --git a/src/sim/rb_sim/mod.rs b/src/sim/rb_sim/mod.rs
new file mode 100644
index 0000000..1818052
--- /dev/null
+++ b/src/sim/rb_sim/mod.rs
@@ -0,0 +1,131 @@
+pub mod rb_entity;
+
+use fxhash::FxHashMap;
+use rapier2d::{
+    dynamics::{self},
+    geometry,
+    glamx::vec2,
+    math, prelude,
+};
+
+use crate::{
+    config::{CELLS_IN_CHUNK, PHYSICS_DELTA_TIME},
+    sim::{
+        cell::{cell::Cell, materials::MaterialId},
+        rb_sim::rb_entity::RbEntity,
+    },
+};
+
+pub struct PhysicsManager {
+    rigid_body_set: prelude::RigidBodySet,
+    collider_set: prelude::ColliderSet,
+    physics_pipeline: prelude::PhysicsPipeline,
+    integration_parameters: prelude::IntegrationParameters,
+    island_manager: prelude::IslandManager,
+    broad_phase: prelude::DefaultBroadPhase,
+    narrow_phase: prelude::NarrowPhase,
+    impulse_joint_set: prelude::ImpulseJointSet,
+    multibody_joint_set: prelude::MultibodyJointSet,
+    ccd_solver: prelude::CCDSolver,
+}
+
+impl PhysicsManager {
+    pub fn new() -> Self {
+        PhysicsManager {
+            rigid_body_set: prelude::RigidBodySet::new(),
+            collider_set: prelude::ColliderSet::new(),
+            physics_pipeline: prelude::PhysicsPipeline::new(),
+            integration_parameters: prelude::IntegrationParameters {
+                // 20 pixels = 1 meter
+                length_unit: 20.0,
+                dt: PHYSICS_DELTA_TIME,
+                ..prelude::IntegrationParameters::default()
+            },
+            island_manager: prelude::IslandManager::new(),
+            broad_phase: prelude::DefaultBroadPhase::new(),
+            narrow_phase: prelude::NarrowPhase::new(),
+            impulse_joint_set: prelude::ImpulseJointSet::new(),
+            multibody_joint_set: prelude::MultibodyJointSet::new(),
+            ccd_solver: prelude::CCDSolver::new(),
+        }
+    }
+}
+
+pub struct RbSimManager {
+    physics_manager: PhysicsManager,
+    pub rb_entities: FxHashMap<u32, RbEntity>,
+}
+
+impl RbSimManager {
+    pub fn rb_tick(&mut self, delta_time: f32) {
+        let gravity = vec2(0.0, -9.81);
+
+        self.physics_manager.physics_pipeline.step(
+            gravity,
+            &self.physics_manager.integration_parameters,
+            &mut self.physics_manager.island_manager,
+            &mut self.physics_manager.broad_phase,
+            &mut self.physics_manager.narrow_phase,
+            &mut self.physics_manager.rigid_body_set,
+            &mut self.physics_manager.collider_set,
+            &mut self.physics_manager.impulse_joint_set,
+            &mut self.physics_manager.multibody_joint_set,
+            &mut self.physics_manager.ccd_solver,
+            &(),
+            &(),
+        );
+    }
+
+    pub fn get_rb_entity_position(&self, entity_id: u32) -> Option<(f32, f32)> {
+        let entity = self.rb_entities.get(&entity_id);
+        match entity {
+            Some(entity) => {
+                let rb = self.physics_manager.rigid_body_set.get(entity.rb_parent);
+                rb.map(|rb| (rb.position().translation.x, rb.position().translation.y))
+            }
+            None => return None,
+        }
+    }
+
+    pub fn test(&mut self) {
+        /* Create the ground. */
+        let collider = geometry::ColliderBuilder::cuboid(100.0, 0.1).build();
+        self.physics_manager.collider_set.insert(collider);
+
+        /* Create the bouncing ball. */
+        let rigid_body = dynamics::RigidBodyBuilder::dynamic()
+            .translation(math::Vector::new(0.0, 10.0))
+            .build();
+        let collider = geometry::ColliderBuilder::ball(0.5)
+            .restitution(0.7)
+            .build();
+        let ball_body_handle = self.physics_manager.rigid_body_set.insert(rigid_body);
+        self.physics_manager.collider_set.insert_with_parent(
+            collider,
+            ball_body_handle,
+            &mut self.physics_manager.rigid_body_set,
+        );
+
+        let test_cells = Box::new([Cell::void(); CELLS_IN_CHUNK]);
+        let mut rb_entity = RbEntity {
+            id: 0,
+            cells: test_cells,
+            rb_parent: ball_body_handle,
+        };
+
+        for x in 0..10 {
+            for y in 0..10 {
+                rb_entity.set_cell_at_local_position(x, y, Cell::from_material(MaterialId::Wood));
+            }
+        }
+
+        self.rb_entities.insert(0, rb_entity);
+    }
+
+    pub fn new() -> Self {
+        RbSimManager {
+            physics_manager: PhysicsManager::new(),
+            rb_entities: FxHashMap::default(),
+        }
+    }
+}