Implement basic game saving

Cargo.toml

@@ -7,6 +7,8 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-rltk = { version = "0.8.0" }
-specs = "0.16.1"
+rltk = { version = "0.8.0", features=["serde"] }
+specs = {version = "0.16.1", features=["serde"] }
 specs-derive = "0.4.1"
+serde= { version="1.0.93", features = ["derive"]}
+serde_json = "1.0.39"

src/components.rs

@@ -1,14 +1,17 @@
 use rltk::RGB;
+use serde::{Deserialize, Serialize};
+use specs::error::NoError;
 use specs::prelude::*;
+use specs::saveload::{ConvertSaveload, Marker};
 use specs_derive::*;
 
-#[derive(Component)]
+#[derive(Component, ConvertSaveload, Clone)]
 pub struct Position {
     pub x: i32,
     pub y: i32,
 }
 
-#[derive(Component)]
+#[derive(Component, ConvertSaveload, Clone)]
 pub struct Renderable {
     pub glyph: rltk::FontCharType,
     pub fg: RGB,
@@ -16,10 +19,10 @@ pub struct Renderable {
     pub render_order: i32,
 }
 
-#[derive(Component, Debug, Default)]
+#[derive(Component, Debug, Clone, Serialize, Deserialize, Default)]
 pub struct Player {}
 
-#[derive(Component)]
+#[derive(Component, ConvertSaveload, Clone)]
 pub struct Viewshed {
     pub visible_tiles: Vec<rltk::Point>,
     pub range: i32,
@@ -36,10 +39,10 @@ impl Default for Viewshed {
     }
 }
 
-#[derive(Component, Debug, Default)]
+#[derive(Component, Debug, Serialize, Deserialize, Clone, Default)]
 pub struct Monster {}
 
-#[derive(Component, Debug)]
+#[derive(Component, Debug, ConvertSaveload, Clone)]
 pub struct Name {
     pub name: String,
 }
@@ -52,10 +55,10 @@ impl Name {
     }
 }
 
-#[derive(Component, Debug, Default)]
+#[derive(Component, Debug, Serialize, Deserialize, Clone, Default)]
 pub struct BlocksTile {}
 
-#[derive(Component, Debug)]
+#[derive(Component, Debug, ConvertSaveload, Clone)]
 pub struct CombatStats {
     pub max_hp: i32,
     pub hp: i32,
@@ -63,12 +66,12 @@ pub struct CombatStats {
     pub power: i32,
 }
 
-#[derive(Component, Debug, Clone)]
+#[derive(Component, Debug, ConvertSaveload, Clone)]
 pub struct WantsToMelee {
     pub target: Entity,
 }
 
-#[derive(Component, Debug)]
+#[derive(Component, Debug, ConvertSaveload, Clone)]
 pub struct SufferDamage {
     pub amount: Vec<i32>,
 }
@@ -86,55 +89,62 @@ impl SufferDamage {
     }
 }
 
-#[derive(Component, Debug, Default)]
+#[derive(Component, Debug, Serialize, Deserialize, Clone, Default)]
 pub struct Item {}
 
-#[derive(Component, Debug)]
+#[derive(Component, Debug, Serialize, Deserialize, Clone, Default)]
+pub struct Consumable {}
+
+#[derive(Component, Debug, ConvertSaveload, Clone)]
+pub struct Ranged {
+    pub range: i32,
+}
+
+#[derive(Component, Debug, ConvertSaveload, Clone)]
+pub struct InflictsDamage {
+    pub damage: i32,
+}
+
+#[derive(Component, Debug, ConvertSaveload, Clone)]
+pub struct AreaOfEffect {
+    pub radius: i32,
+}
+
+#[derive(Component, Debug, ConvertSaveload, Clone)]
+pub struct Confusion {
+    pub turns: i32,
+}
+
+#[derive(Component, Debug, ConvertSaveload, Clone)]
 pub struct ProvidesHealing {
     pub heal_amount: i32,
 }
 
-#[derive(Component, Debug, Clone)]
+#[derive(Component, Debug, ConvertSaveload)]
 pub struct InBackpack {
     pub owner: Entity,
 }
 
-#[derive(Component, Debug, Clone)]
+#[derive(Component, Debug, ConvertSaveload)]
 pub struct WantsToPickupItem {
     pub collected_by: Entity,
     pub item: Entity,
 }
 
-#[derive(Component, Debug)]
+#[derive(Component, Debug, ConvertSaveload)]
 pub struct WantsToUseItem {
     pub item: Entity,
     pub target: Option<rltk::Point>,
 }
 
-#[derive(Component, Debug, Clone)]
+#[derive(Component, Debug, ConvertSaveload)]
 pub struct WantsToDropItem {
     pub item: Entity,
 }
 
-#[derive(Component, Debug, Default)]
-pub struct Consumable {}
+pub struct SerializeMe;
 
-#[derive(Component, Debug)]
-pub struct Ranged {
-    pub range: i32,
-}
-
-#[derive(Component, Debug)]
-pub struct InflictsDamage {
-    pub damage: i32,
-}
-
-#[derive(Component, Debug)]
-pub struct AreaOfEffect {
-    pub radius: i32,
-}
-
-#[derive(Component, Debug)]
-pub struct Confusion {
-    pub turns: i32,
+#[derive(Component, Serialize, Deserialize, Clone)]
+pub struct SerializationHelper {
+    pub map: crate::map::Map,
 }

src/main.rs

@@ -1,5 +1,7 @@
 use rltk::{GameState, Point, Rltk};
 use specs::prelude::*;
+use specs::saveload::{SimpleMarker, SimpleMarkerAllocator};
+extern crate serde;
 
 mod components;
 mod damage_system;
@@ -12,6 +14,7 @@ mod melee_combat_system;
 mod monster_ai_system;
 mod player;
 mod rect;
+pub mod saveload_system;
 mod spawner;
 mod visibility_system;
 
@@ -55,6 +58,7 @@ pub enum RunState {
     MainMenu {
         menu_selection: gui::MainMenuSelection,
     },
+    SaveGame,
 }
 
 pub struct State {
@@ -240,6 +244,13 @@ impl GameState for State {
                     },
                 }
             }
+            RunState::SaveGame => {
+                saveload_system::save_game(&mut self.ecs);
+
+                newrunstate = RunState::MainMenu {
+                    menu_selection: gui::MainMenuSelection::LoadGame,
+                }
+            }
         }
 
         {
@@ -283,8 +294,12 @@ fn main() -> rltk::BError {
         InflictsDamage,
         AreaOfEffect,
         Confusion,
+        SimpleMarker<SerializeMe>,
+        SerializationHelper,
     );
 
+    gs.ecs.insert(SimpleMarkerAllocator::<SerializeMe>::new());
+
     let map = Map::new_map_rooms_and_corridors();
     let (player_x, player_y) = map.rooms[0].center();
 

src/map.rs

@@ -1,5 +1,6 @@
 use crate::Rect;
 use rltk::{Algorithm2D, BaseMap, Point, RandomNumberGenerator, Rltk, SmallVec, RGB};
+use serde::{Deserialize, Serialize};
 use specs::prelude::*;
 use std::cmp::{max, min};
 
@@ -7,12 +8,13 @@ pub const MAP_WIDTH: usize = 80;
 pub const MAP_HEIGHT: usize = 43;
 pub const MAP_COUNT: usize = MAP_HEIGHT * MAP_WIDTH;
 
-#[derive(PartialEq, Copy, Clone)]
+#[derive(PartialEq, Copy, Clone, Serialize, Deserialize)]
 pub enum TileType {
     Wall,
     Floor,
 }
 
+#[derive(Default, Serialize, Deserialize, Clone)]
 pub struct Map {
     pub tiles: Vec<TileType>,
     pub rooms: Vec<Rect>,
@@ -21,6 +23,9 @@ pub struct Map {
     pub revealed_tiles: Vec<bool>,
     pub visible_tiles: Vec<bool>,
     pub blocked: Vec<bool>,
+
+    #[serde(skip_serializing)]
+    #[serde(skip_deserializing)]
     pub tile_content: Vec<Vec<Entity>>,
 }
 

src/player.rs

@@ -104,6 +104,9 @@ pub fn player_input(gs: &mut State, ctx: &mut Rltk) -> RunState {
             // Show item drop screen
             VirtualKeyCode::D => return RunState::ShowDropItem,
 
+            // Save and Quit
+            VirtualKeyCode::Escape => return RunState::SaveGame,
+
             _ => return RunState::AwaitingInput,
         },
     }

src/rect.rs

@@ -1,3 +1,6 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(PartialEq, Copy, Clone, Serialize, Deserialize)]
 pub struct Rect {
     pub x1: i32,
     pub x2: i32,

src/saveload_system.rs

@@ -0,0 +1,79 @@
+use crate::components::*;
+use specs::error::NoError;
+use specs::prelude::*;
+use specs::saveload::{
+    DeserializeComponents, MarkedBuilder, SerializeComponents, SimpleMarker, SimpleMarkerAllocator,
+};
+use std::fs;
+use std::fs::File;
+use std::path::Path;
+
+macro_rules! serialize_individually {
+    ($ecs:expr, $ser:expr, $data:expr, $( $type:ty),*) => {
+        $(
+        SerializeComponents::<NoError, SimpleMarker<SerializeMe>>::serialize(
+            &( $ecs.read_storage::<$type>(), ),
+            &$data.0,
+            &$data.1,
+            &mut $ser,
+        )
+        .unwrap();
+        )*
+    };
+}
+
+pub fn save_game(ecs: &mut World) {
+    // Create helper
+    let mapcopy = ecs.get_mut::<crate::map::Map>().unwrap().clone();
+    let savehelper = ecs
+        .create_entity()
+        .with(SerializationHelper { map: mapcopy })
+        .marked::<SimpleMarker<SerializeMe>>()
+        .build();
+
+    // Actually serialize
+    {
+        let data = (
+            ecs.entities(),
+            ecs.read_storage::<SimpleMarker<SerializeMe>>(),
+        );
+
+        let writer = File::create("./savegame.json").unwrap();
+        let mut serializer = serde_json::Serializer::new(writer);
+        serialize_individually!(
+            ecs,
+            serializer,
+            data,
+            Position,
+            Renderable,
+            Player,
+            Viewshed,
+            Monster,
+            Name,
+            BlocksTile,
+            CombatStats,
+            SufferDamage,
+            WantsToMelee,
+            Item,
+            Consumable,
+            Ranged,
+            InflictsDamage,
+            AreaOfEffect,
+            Confusion,
+            ProvidesHealing,
+            InBackpack,
+            WantsToPickupItem,
+            WantsToUseItem,
+            WantsToDropItem,
+            SerializationHelper
+        );
+    }
+
+    // Clean up
+    ecs.delete_entity(savehelper)
+        .expect("Failed to clean up savehelper component");
+}
+
+pub fn does_save_exist() -> bool {
+    Path::new("./savegame.json").exists()
+}

src/spawner.rs

@@ -1,10 +1,11 @@
 use crate::components::{
     AreaOfEffect, BlocksTile, CombatStats, Confusion, Consumable, InflictsDamage, Item, Monster,
-    Name, Player, Position, ProvidesHealing, Ranged, Renderable, Viewshed,
+    Name, Player, Position, ProvidesHealing, Ranged, Renderable, SerializeMe, Viewshed,
 };
 use crate::{Rect, MAP_WIDTH};
 use rltk::{RandomNumberGenerator, RGB};
 use specs::prelude::*;
+use specs::saveload::{MarkedBuilder, SimpleMarker};
 
 const MAX_MONSTERS: i32 = 4;
 const MAX_ITEMS: i32 = 2;
@@ -31,6 +32,7 @@ pub fn player(ecs: &mut World, player_x: i32, player_y: i32) -> Entity {
             defense: 2,
             power: 5,
         })
+        .marked::<SimpleMarker<SerializeMe>>()
         .build()
 }
 
@@ -76,6 +78,7 @@ fn monster<S: ToString>(ecs: &mut World, x: i32, y: i32, glyph: rltk::FontCharTy
             defense: 1,
             power: 4,
         })
+        .marked::<SimpleMarker<SerializeMe>>()
         .build();
 }
 
@@ -166,6 +169,7 @@ fn magic_missile_scroll(ecs: &mut World, x: i32, y: i32) {
         .with(Consumable {})
         .with(Ranged { range: 6 })
         .with(InflictsDamage { damage: 8 })
+        .marked::<SimpleMarker<SerializeMe>>()
         .build();
 }
 
@@ -199,6 +203,7 @@ fn fireball_scroll(ecs: &mut World, x: i32, y: i32) {
         .with(Ranged { range: 6 })
         .with(InflictsDamage { damage: 20 })
         .with(AreaOfEffect { radius: 3 })
+        .marked::<SimpleMarker<SerializeMe>>()
         .build();
 }
 
@@ -216,5 +221,6 @@ fn confusion_scroll(ecs: &mut World, x: i32, y: i32) {
         .with(Consumable {})
         .with(Ranged { range: 6 })
         .with(Confusion { turns: 4 })
+        .marked::<SimpleMarker<SerializeMe>>()
         .build();
 }