Blinker POC. Possible framework for constantly-updating entities.

client/src/graphics/window.rs

@@ -266,6 +266,11 @@ impl Window {
                                 sim.toggle_no_clip();
                             }
                         }
+                        KeyCode::KeyB if state == ElementState::Pressed => {
+                            if let Some(sim) = self.sim.as_mut() {
+                                sim.debug_spawn_blinker();
+                            }
+                        }
                         KeyCode::F1 if state == ElementState::Pressed => {
                             self.gui_state.toggle_gui();
                         }

client/src/local_character_controller.rs

@@ -3,7 +3,7 @@ use common::{math, proto::Position};
 pub struct LocalCharacterController {
     /// The last extrapolated inter-frame view position, used for rendering and gravity-specific
     /// orientation computations
-    position: Position,
+    pub position: Position,
 
     /// The up vector relative to position, ignoring orientation
     up: na::UnitVector3<f32>,

client/src/prediction.rs

@@ -119,6 +119,7 @@ mod tests {
             movement: na::Vector3::x(),
             jump: false,
             no_clip: true,
+            debug_spawn_blinker: false,
             block_update: None,
         };
 

client/src/sim.rs

@@ -63,6 +63,7 @@ pub struct Sim {
     no_clip: bool,
     /// Whether no_clip will be toggled next step
     toggle_no_clip: bool,
+    debug_spawn_blinker: bool,
     /// Whether the current step starts with a jump
     is_jumping: bool,
     /// Whether the jump button has been pressed since the last step
@@ -100,6 +101,7 @@ impl Sim {
             average_movement_input: na::zero(),
             no_clip: true,
             toggle_no_clip: false,
+            debug_spawn_blinker: false,
             is_jumping: false,
             jump_pressed: false,
             jump_held: false,
@@ -144,6 +146,11 @@ impl Sim {
         self.toggle_no_clip = true;
     }
 
+    pub fn debug_spawn_blinker(&mut self) {
+        // Note: the blinker currently does nothing but update internal state
+        self.debug_spawn_blinker = true;
+    }
+
     pub fn set_jump_held(&mut self, jump_held: bool) {
         self.jump_held = jump_held;
         self.jump_pressed = jump_held || self.jump_pressed;
@@ -367,6 +374,9 @@ impl Sim {
                     node = Some(x.node);
                     builder.add(x);
                 }
+                TickerEntity(x) => {
+                    builder.add(x);
+                }
             };
         }
         let entity = self.world.spawn(builder.build());
@@ -392,6 +402,7 @@ impl Sim {
             movement: sanitize_motion_input(orientation * self.average_movement_input),
             jump: self.is_jumping,
             no_clip: self.no_clip,
+            debug_spawn_blinker: self.debug_spawn_blinker,
             block_update: self.get_local_character_block_update(),
         };
         let generation = self
@@ -404,6 +415,7 @@ impl Sim {
             character_input,
             orientation: self.local_character_controller.orientation(),
         });
+        self.debug_spawn_blinker = false;
     }
 
     fn update_view_position(&mut self) {
@@ -425,6 +437,7 @@ impl Sim {
                 / (self.since_input_sent.as_secs_f32() / self.cfg.step_interval.as_secs_f32()),
             jump: self.is_jumping,
             no_clip: self.no_clip,
+            debug_spawn_blinker: self.debug_spawn_blinker,
             block_update: None,
         };
         character_controller::run_character_step(

common/src/lib.rs

@@ -29,6 +29,7 @@ mod plane;
 pub mod proto;
 mod sim_config;
 pub mod terraingen;
+pub mod ticker;
 pub mod traversal;
 pub mod voxel_math;
 pub mod world;

common/src/proto.rs

@@ -1,8 +1,8 @@
 use serde::{Deserialize, Serialize};
 
 use crate::{
-    dodeca, graph::NodeId, node::ChunkId, voxel_math::Coords, world::Material, EntityId, SimConfig,
-    Step,
+    dodeca, graph::NodeId, node::ChunkId, ticker::TickerEntity, voxel_math::Coords,
+    world::Material, EntityId, SimConfig, Step,
 };
 
 #[derive(Debug, Serialize, Deserialize)]
@@ -70,6 +70,7 @@ pub struct CharacterInput {
     pub movement: na::Vector3<f32>,
     pub jump: bool,
     pub no_clip: bool,
+    pub debug_spawn_blinker: bool,
     pub block_update: Option<BlockUpdate>,
 }
 
@@ -90,6 +91,7 @@ pub struct SerializedVoxelData {
 pub enum Component {
     Character(Character),
     Position(Position),
+    TickerEntity(TickerEntity),
 }
 
 #[derive(Debug, Serialize, Deserialize)]

common/src/ticker.rs

@@ -0,0 +1,35 @@
+use crate::Step;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct TickerEntity {
+    pub last_ticked: Step,
+    pub ticker: Ticker,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct Ticker {
+    on: bool,
+}
+
+impl Ticker {
+    pub fn new() -> Self {
+        Self { on: false }
+    }
+    pub fn tick(&mut self, _step: Step) {
+        self.on = !self.on;
+
+        // Just for testing
+        if self.on {
+            println!("Ticked ON!");
+        } else {
+            println!("Ticked OFF!");
+        }
+    }
+}
+
+impl Default for Ticker {
+    fn default() -> Self {
+        Ticker::new()
+    }
+}

server/src/sim.rs

@@ -21,6 +21,7 @@ use common::{
         Character, CharacterInput, CharacterState, ClientHello, Command, Component, FreshNode,
         Position, Spawns, StateDelta,
     },
+    ticker::{Ticker, TickerEntity},
     traversal::{ensure_nearby, nearby_nodes},
     worldgen::ChunkParams,
     EntityId, SimConfig, Step,
@@ -30,14 +31,15 @@ use crate::postcard_helpers::{self, SaveEntity};
 
 pub struct Sim {
     cfg: Arc<SimConfig>,
-    rng: SmallRng,
     step: Step,
-    entity_ids: FxHashMap<EntityId, Entity>,
+    pub rng: SmallRng,
+    pub entity_ids: FxHashMap<EntityId, Entity>,
     world: hecs::World,
     graph: Graph,
     /// Voxel data that has been fetched from a savefile but not yet introduced to the graph
     preloaded_voxel_data: FxHashMap<ChunkId, VoxelData>,
     spawns: Vec<Entity>,
+    pending_ticker_spawns: Vec<(Position, TickerEntity)>,
     despawns: Vec<EntityId>,
     graph_entities: GraphEntities,
     /// All nodes that have entity-related information yet to be saved
@@ -51,13 +53,14 @@ pub struct Sim {
 impl Sim {
     pub fn new(cfg: Arc<SimConfig>, save: &save::Save) -> Self {
         let mut result = Self {
-            rng: SmallRng::from_entropy(),
             step: 0,
+            rng: SmallRng::from_entropy(),
             entity_ids: FxHashMap::default(),
             world: hecs::World::new(),
             graph: Graph::new(cfg.chunk_size),
             preloaded_voxel_data: FxHashMap::default(),
             spawns: Vec::new(),
+            pending_ticker_spawns: Vec::new(),
             despawns: Vec::new(),
             graph_entities: GraphEntities::new(),
             dirty_nodes: FxHashSet::default(),
@@ -205,6 +208,7 @@ impl Sim {
             movement: na::Vector3::zeros(),
             jump: false,
             no_clip: true,
+            debug_spawn_blinker: false,
             block_update: None,
         };
         let entity = self.world.spawn((id, position, character, initial_input));
@@ -272,6 +276,10 @@ impl Sim {
         let span = error_span!("step", step = self.step);
         let _guard = span.enter();
 
+        for (_entity, ticker_entity) in self.world.query::<&mut TickerEntity>().iter() {
+            ticker_entity.ticker.tick(self.step);
+        }
+
         let mut pending_block_updates: Vec<BlockUpdate> = vec![];
 
         // Extend graph structure
@@ -332,6 +340,13 @@ impl Sim {
             .iter()
         {
             let prev_node = position.node;
+            if input.debug_spawn_blinker {
+                let ticker: TickerEntity = TickerEntity {
+                    last_ticked: 0,
+                    ticker: Ticker::new(),
+                };
+                self.pending_ticker_spawns.push((*position, ticker));
+            }
             character_controller::run_character_step(
                 &self.cfg,
                 &self.graph,
@@ -350,6 +365,16 @@ impl Sim {
             self.dirty_nodes.insert(position.node);
         }
 
+        let pending_ticker_spawns = std::mem::take(&mut self.pending_ticker_spawns);
+        for (position, ticker) in pending_ticker_spawns {
+            let id = self.new_id();
+            let entity = self.world.spawn((id, position, ticker));
+            self.graph_entities.insert(position.node, entity);
+            self.entity_ids.insert(id, entity);
+            self.spawns.push(entity);
+            self.dirty_nodes.insert(position.node);
+        }
+
         let mut accepted_block_updates: Vec<BlockUpdate> = vec![];
 
         for block_update in pending_block_updates.into_iter() {
@@ -412,7 +437,7 @@ impl Sim {
         (spawns, delta)
     }
 
-    fn new_id(&mut self) -> EntityId {
+    pub fn new_id(&mut self) -> EntityId {
         loop {
             let id = self.rng.gen();
             if !self.entity_ids.contains_key(&id) {