Added staring position modifier

README.md

@@ -34,7 +34,7 @@ If you want to check how the maps look like, then:
     * [ ] Wave Function Collapse
   * Map modifiers (filters)
     * [ ] Area exit point
-    * [ ] Area starting point
+    * [x] Area starting point
     * [x] Cellular automata
     * [ ] Cull unreachable areas
     * [ ] Voronoi spawning

demo/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "mapgen-demo"
-version = "0.1.0"
+version = "0.1.1"
 authors = ["Krzysztof Langner <klangner@gmail.com>"]
 edition = "2018"
 

demo/src/main.rs

@@ -1,4 +1,3 @@
-use rand::prelude::*;
 use amethyst::{
     assets::{AssetStorage, Loader},
     core::{
@@ -14,6 +13,7 @@ use amethyst::{
         sprite::{SpriteSheet, SpriteSheetFormat, SpriteSheetHandle},
         types::DefaultBackend,
         RenderFlat2D, RenderToWindow, RenderingBundle, Texture,
+        palette::Srgba,
     },
     tiles::{MortonEncoder, RenderTiles2D, Tile, TileMap},
     utils::application_root_dir,
@@ -21,9 +21,10 @@ use amethyst::{
     winit,
 };
 use mapgen::dungeon::{
-    MapGenerator,
-    map::{Map, TileType},
+    MapBuilder,
+    map::{Map, Point, TileType},
     cellular_automata::CellularAutomataGen,
+    starting_point::{AreaStartingPosition, XStart, YStart},
 };
 
 
@@ -33,12 +34,25 @@ struct MapTiles ;
 impl Tile for MapTiles {
     fn sprite(&self, p: Point3<u32>, world: &World) -> Option<usize> {
         let map = world.read_resource::<Map>();
-        if map.at(p.x as usize, p.y as usize) == TileType::Wall {
+        let player_pos = Point::new(p.x as usize, p.y as usize);
+        if map.starting_point == Some(player_pos) {
+            Some(64)
+        } else if map.at(p.x as usize, p.y as usize) == TileType::Wall {
             Some(35)
         } else {
             Some(46)
         }
     }
+
+    fn tint(&self, p: Point3<u32>, world: &World) -> Srgba {
+        let map = world.read_resource::<Map>();
+        let player_pos = Point::new(p.x as usize, p.y as usize);
+        if map.starting_point == Some(player_pos) {
+            Srgba::new(1.0, 1.0, 0.0, 1.0)
+        } else {
+            Srgba::new(1.0, 1.0, 1.0, 1.0)
+        }
+    }
 }
 
 fn load_tiles_sprite_sheet(world: &mut World, png_path: &str, ron_path: &str) -> SpriteSheetHandle {
@@ -67,9 +81,9 @@ fn init_camera(world: &mut World, transform: Transform, camera: Camera) -> Entit
 }
 
 fn init_map(world: &mut World) {
-    let gen = CellularAutomataGen::new(80, 50);
-    let mut rng = StdRng::seed_from_u64(0);
-    let map = gen.generate_map(&mut rng);
+    let map = MapBuilder::new(Box::new(CellularAutomataGen::new(80, 50)))
+        .with(AreaStartingPosition::new(XStart::CENTER, YStart::CENTER))
+        .build_map();
     world.insert(map); 
 }
 

src/dungeon/cellular_automata.rs

@@ -23,7 +23,6 @@
 //! ```
 //! 
 
-
 use rand::prelude::*;
 use super::{MapGenerator, MapModifier};
 use super::map::{Map, TileType};

src/dungeon/map.rs

@@ -9,14 +9,22 @@
 
 /// Position on the map
 #[derive(PartialEq, Copy, Clone, Debug, Eq, Hash)]
-pub struct Position {
+pub struct Point {
     x: usize,
     y: usize
 }
 
-impl Position {
-    pub fn new(x: usize, y: usize) -> Position {
-        Position {x, y}
+impl Point {
+    /// Create new point
+    pub fn new(x: usize, y: usize) -> Point {
+        Point {x, y}
+    }
+
+    /// Euclidean distance to a given point
+    pub fn distance_to(self, point: &Point) -> f32 {
+        let a = (self.x as f32 - point.x as f32).powf(2.0);
+        let b = (self.y as f32 - point.y as f32).powf(2.0);
+        (a + b).sqrt()
     }
 }
 
@@ -32,8 +40,8 @@ pub struct Map {
     pub tiles : Vec<TileType>,
     pub width : usize,
     pub height : usize,
-    pub starting_point: Option<Position>,
-    pub exit_point: Option<Position>
+    pub starting_point: Option<Point>,
+    pub exit_point: Option<Point>
 }
 
 impl Map {
@@ -70,6 +78,14 @@ impl Map {
 mod tests {
     use super::*;
 
+    #[test]
+    fn test_distance() {
+        let p1 = Point::new(10, 10);
+        let p2 = Point::new(14, 7);
+        let distance = p1.distance_to(&p2);
+        assert_eq!(distance, 5.0);
+    }
+
     #[test]
     fn test_new_map() {
         let map = Map::new(10, 10);

src/dungeon/mod.rs

@@ -6,10 +6,30 @@
 //! * MapGenerators are use to create initial map.
 //! * MapModifiers modify existing map.
 //! 
+//! Example
+//! ```
+//! use mapgen::dungeon::{
+//!     MapBuilder,
+//!     map::{Map, Point, TileType},
+//!     cellular_automata::CellularAutomataGen,
+//!     starting_point::{AreaStartingPosition, XStart, YStart},
+//! };
+//! 
+//! let map = MapBuilder::new(Box::new(CellularAutomataGen::new(80, 50)))
+//!             .with(AreaStartingPosition::new(XStart::CENTER, YStart::CENTER))
+//!             .build_map();
+//! 
+//! assert_eq!(map.width, 80);
+//! assert_eq!(map.height, 50);
+//! assert_eq!(map.starting_point.is_some(), true);
+//! ```
+//! 
 
 pub mod map;
 pub mod cellular_automata;
+pub mod starting_point;
 
+use std::time::{SystemTime, UNIX_EPOCH};
 use rand::prelude::*;
 use map::Map;
 
@@ -34,16 +54,19 @@ pub struct MapBuilder {
 }
 
 impl MapBuilder {
+    /// Create Map Builder with initial map generator
     pub fn new(generator : Box<dyn MapGenerator>) -> MapBuilder {
+        let system_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Can't access system time");
         MapBuilder { 
             generator, 
             modifiers: Vec::new(),
-            rng: StdRng::seed_from_u64(0)
+            rng: StdRng::seed_from_u64(system_time.as_secs())
         }
     }
 
-    pub fn with(&mut self, modifier : Box<dyn MapModifier>) {
+    pub fn with(&mut self, modifier : Box<dyn MapModifier>) -> &mut MapBuilder {
         self.modifiers.push(modifier);
+        self
     }
 
     pub fn build_map(&mut self) -> Map {
@@ -51,10 +74,31 @@ impl MapBuilder {
         
         // Build additional layers in turn
         for modifier in self.modifiers.iter() {
-            modifier.modify_map(&mut self.rng, &mut map);
+            map = modifier.modify_map(&mut self.rng, &map);
         }
 
         map
     }
 }
 
+/// ------------------------------------------------------------------------------------------------
+/// Module unit tests
+/// ------------------------------------------------------------------------------------------------
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use cellular_automata::CellularAutomataGen;
+    use starting_point::{AreaStartingPosition, XStart, YStart};
+
+    #[test]
+    fn test_ca_map() {
+        let map = MapBuilder::new(Box::new(CellularAutomataGen::new(80, 50)))
+            .with(AreaStartingPosition::new(XStart::CENTER, YStart::CENTER))
+            .build_map();
+
+        assert_eq!(map.width, 80);
+        assert_eq!(map.height, 50);
+        assert_eq!(map.starting_point.is_some(), true);
+    }
+
+}

src/dungeon/starting_point.rs

@@ -0,0 +1,97 @@
+//! Add starting point to the map
+//! 
+//! This modifier will try to add starting point by finding the floor title closes 
+//! to the given point.
+//! 
+//! Example generator usage:
+//! ```
+//! use rand::prelude::*;
+//! use mapgen::dungeon::{
+//!     MapModifier,
+//!     map::{Map, Point, TileType},
+//!     starting_point::{AreaStartingPosition, XStart, YStart}
+//! };
+//! 
+//! let mut rng = StdRng::seed_from_u64(100);
+//! let mut map = Map::new(80, 50);
+//! map.set_tile(10, 10, TileType::Floor);
+//! let modifier = AreaStartingPosition::new(XStart::LEFT, YStart::TOP);
+//! let new_map = modifier.modify_map(&mut rng, &map);
+//! 
+//! assert_eq!(new_map.starting_point, Some(Point::new(10, 10)));
+//! ```
+//! 
+
+use rand::prelude::StdRng;
+use super::{MapModifier};
+use super::map::{Map, Point, TileType};
+
+
+/// Initial x region position
+pub enum XStart { LEFT, CENTER, RIGHT }
+
+/// Initial y region position
+pub enum YStart { TOP, CENTER, BOTTOM }
+
+/// Add starting position to the map
+pub struct AreaStartingPosition {
+    x : XStart, 
+    y : YStart
+}
+
+impl MapModifier for AreaStartingPosition {
+    fn modify_map(&self, _: &mut StdRng, map: &Map)  -> Map {
+        self.build(map)
+    }
+}
+
+impl AreaStartingPosition {
+    /// Create new modifier with given region
+    pub fn new(x : XStart, y : YStart) -> Box<AreaStartingPosition> {
+        Box::new(AreaStartingPosition{
+            x, y
+        })
+    }
+
+    fn build(&self, map : &Map) -> Map {
+        let seed_x;
+        let seed_y;
+
+        match self.x {
+            XStart::LEFT => seed_x = 1,
+            XStart::CENTER => seed_x = map.width / 2,
+            XStart::RIGHT => seed_x = map.width - 2
+        }
+
+        match self.y {
+            YStart::TOP => seed_y = 1,
+            YStart::CENTER => seed_y = map.height / 2,
+            YStart::BOTTOM => seed_y = map.height - 2
+        }
+
+        let mut available_floors : Vec<(usize, f32)> = Vec::new();
+        for (idx, tiletype) in map.tiles.iter().enumerate() {
+            if *tiletype == TileType::Floor {
+                available_floors.push(
+                    (
+                        idx,
+                        Point::new(idx % map.width, idx / map.width)
+                            .distance_to(&Point::new(seed_x, seed_y))
+                    )
+                );
+            }
+        }
+        if available_floors.is_empty() {
+            panic!("No valid floors to start on");
+        }
+
+        available_floors.sort_by(|a,b| a.1.partial_cmp(&b.1).unwrap());
+
+        let start_x = available_floors[0].0 % map.width;
+        let start_y = available_floors[0].0 / map.width;
+
+        let mut new_map = map.clone();
+        new_map.starting_point = Some(Point::new(start_x, start_y));
+        new_map
+    }
+}