feat(wip): add systems

Author: mdssjc

books/hands-on-rust/dungeoncrawl/src/main.rs

@@ -25,6 +25,7 @@ use prelude::*;
 
 struct State {
     ecs: World,
+    resources: Resources,
     systems: Schedule,
 }
 
@@ -39,6 +40,7 @@ impl State {
         resources.insert(Camera::new(map_builder.player_start));
         Self {
             ecs,
+            resources,
             systems: build_scheduler(),
         }
     }
@@ -52,6 +54,7 @@ impl GameState for State {
         ctx.cls();
         self.resources.insert(ctx.key);
         self.systems.execute(&mut self.ecs, &mut self.resources);
+        render_draw_buffer(ctx).expect("Render error");
     }
 }
 

books/hands-on-rust/dungeoncrawl/src/systems/entity_render.rs

@@ -0,0 +1,17 @@
+use crate::prelude::*;
+
+#[system]
+#[read_component(Point)]
+#[read_component(Render)]
+pub fn entity_render(ecs: &SubWorld, #[resource] camera: &Camera) {
+    let mut draw_batch = DrawBatch::new();
+    draw_batch.target(1);
+    let offset = Point::new(camera.left_x, camera.top_y);
+
+    <(&Point, &Render)>::query()
+        .iter(ecs)
+        .for_each(|(pos, render)| {
+            draw_batch.set(*pos - offset, render.color, render.glyph);
+        });
+    draw_batch.submit(5000).expect("Batch error");
+}

books/hands-on-rust/dungeoncrawl/src/systems/map_render.rs

@@ -0,0 +1,22 @@
+use crate::prelude::*;
+
+#[system]
+pub fn map_render(#[resource] map: &Map, #[resource] camera: &Camera) {
+    let mut draw_batch = DrawBatch::new();
+    draw_batch.target(0);
+    for y in camera.top_y..=camera.bottom_y {
+        for x in camera.left_x..camera.right_x {
+            let pt = Point::new(x, y);
+            let offset = Point::new(camera.left_x, camera.top_y);
+            if map.in_bounds(pt) {
+                let idx = map_idx(x, y);
+                let glyph = match map.tiles[idx] {
+                    TileType::Floor => to_cp437('.'),
+                    TileType::Wall => to_cp437('#'),
+                };
+                draw_batch.set(pt - offset, ColorPair::new(WHITE, BLACK), glyph);
+            }
+        }
+    }
+    draw_batch.submit(0).expect("Batch error");
+}

books/hands-on-rust/dungeoncrawl/src/systems/mod.rs

@@ -1,5 +1,12 @@
+mod entity_render;
+mod map_render;
+mod player_input;
 use crate::prelude::*;
 
 pub fn build_scheduler() -> Schedule {
-    Schedule::builder().build()
+    Schedule::builder()
+        .add_system(player_input::player_input_system())
+        .add_system(map_render::map_render_system())
+        .add_system(entity_render::entity_render_system())
+        .build()
 }

books/hands-on-rust/dungeoncrawl/src/systems/player_input.rs

@@ -0,0 +1,32 @@
+use crate::prelude::*;
+
+#[system]
+#[write_component(Point)]
+#[read_component(Player)]
+pub fn player_input(
+    ecs: &mut SubWorld,
+    #[resource] map: &Map,
+    #[resource] key: &Option<VirtualKeyCode>,
+    #[resource] camera: &mut Camera,
+) {
+    if let Some(key) = key {
+        let delta = match key {
+            VirtualKeyCode::Left => Point::new(-1, 0),
+            VirtualKeyCode::Right => Point::new(1, 0),
+            VirtualKeyCode::Up => Point::new(0, -1),
+            VirtualKeyCode::Down => Point::new(0, 1),
+            _ => Point::new(0, 0),
+        };
+
+        if delta.x != 0 || delta.y != 0 {
+            let mut players = <&mut Point>::query().filter(component::<Player>());
+            players.iter_mut(ecs).for_each(|pos| {
+                let destination = *pos + delta;
+                if map.can_enter_tile(destination) {
+                    *pos = destination;
+                    camera.on_player_move(destination);
+                }
+            });
+        }
+    }
+}