Display item selection

src/main.rs

@@ -17,6 +17,7 @@ struct State {
     loaded_chunks: Box<HashMap<(i32, i32), Chunk>>,
     world_pos: (i32, i32),
     player_position: usize,
+    selected_object: Option<TileType>,
     visible: Vec<bool>,
 }
 
@@ -49,6 +50,7 @@ impl State {
             loaded_chunks: Box::new(chunks),
             player_position: (25 * 80) + 40, // Equivalent to point2d_to_index(40, 25) but we haven't initialized it yet
             visible: vec![false; 80 * 50],
+            selected_object: None,
         };
 
         state
@@ -103,12 +105,23 @@ impl State {
             }
         }
     }
+
+    fn select_object(&mut self, pos: Point) {
+        let idx = self.point2d_to_index(pos);
+
+        match self.view.get(idx) {
+            Some(tile) => self.selected_object = Some(*tile),
+            None => {}
+        }
+    }
 }
 
 // Implement the game loop
 impl GameState for State {
     #[allow(non_snake_case)]
     fn tick(&mut self, ctx: &mut Rltk) {
+        // We'll use batched drawing
+        let mut draw_batch = DrawBatch::new();
         match ctx.key {
             None => {} // Nothing happened
             Some(key) => {
@@ -159,7 +172,7 @@ impl GameState for State {
         }
 
         // Clear the screen
-        ctx.cls();
+        draw_batch.cls();
 
         // Iterate the map array, incrementing coordinates as we go.
         let mut y = 0;
@@ -181,7 +194,12 @@ impl GameState for State {
             if !self.visible[i] {
                 fg = fg.to_greyscale();
             }
-            ctx.print_color(x, y, fg, RGB::from_f32(0., 0., 0.), glyph);
+
+            draw_batch.print_color(
+                Point::new(x, y),
+                glyph,
+                ColorPair::new(fg, RGB::from_f32(0., 0., 0.)),
+            );
 
             // Move the coordinates
             x += 1;
@@ -190,16 +208,32 @@ impl GameState for State {
                 y += 1;
             }
         }
+        if ctx.left_click {
+            let mouse_pos = ctx.mouse_pos();
+            self.select_object(Point::from(mouse_pos));
+        }
+
+        // Display selected object below the screen
+        let selected_object_text = match self.selected_object {
+            Some(obj) => format!("{}", obj),
+            None => "".to_string(),
+        };
+        draw_batch.print_color(
+            Point::new(0, 51),
+            selected_object_text,
+            ColorPair::new(RGB::from_f32(1.0, 1.0, 0.0), RGB::from_f32(0., 0., 0.)),
+        );
 
         // Render the player @ symbol
         let ppos = self.index_to_point2d(self.player_position);
-        ctx.print_color(
-            ppos.x,
-            ppos.y,
-            RGB::from_f32(1.0, 1.0, 0.0),
-            RGB::from_f32(0., 0., 0.),
+        draw_batch.print_color(
+            Point::new(ppos.x, ppos.y),
             "@",
+            ColorPair::new(RGB::from_f32(1.0, 1.0, 0.0), RGB::from_f32(0., 0., 0.)),
         );
+
+        draw_batch.submit(0).expect("Batch error");
+        render_draw_buffer(ctx).expect("Render error");
     }
 }
 

src/map.rs

@@ -1,4 +1,5 @@
 use rltk::RandomNumberGenerator;
+use std::fmt::Display;
 
 pub type Chunk = Vec<TileType>;
 
@@ -8,6 +9,15 @@ pub enum TileType {
     Floor,
 }
 
+impl Display for TileType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
+        match self {
+            Self::Floor => f.write_str("Floor"),
+            Self::Wall => f.write_str("Wall"),
+        }
+    }
+}
+
 pub fn new_chunk(seed: u64) -> Chunk {
     let mut map = vec![TileType::Floor; 80 * 50];
     let count = map.len();