Implement platforms

src/app.rs

@@ -121,6 +121,7 @@ impl App {
                 self.game.player.vspeed = -10.0;
                 self.game.player.jumps_left = 0;
             }
+            self.game.player.down_intent = self.input.down(Key::S);
             let terminal_velocity = 60.0;
             self.game.player.vspeed = self
                 .game
@@ -130,14 +131,22 @@ impl App {
             let mut on_screen_tile_ents = Vec::new();
             for_each_tile_on_screen(self.game.camera_offset, self.rt.size(), |tp, _sp| {
                 let tid = self.game.world.tile_at_mut(tp, &self.game.worldgen).mid;
-                if !self.game.tile_db[tid].solid {
+                let tdef = &self.game.tile_db[tid];
+                let Some(bb) = tdef.bb else {
                     return;
-                }
-                let tsize = TILE_SIZE as i32;
+                };
                 let x = tp.x as i32 * TILE_SIZE as i32;
                 let y = tp.y as i32 * TILE_SIZE as i32;
-                let en = s2dc::Entity::from_rect_corners(x, y, x + tsize, y + tsize);
-                on_screen_tile_ents.push(en);
+                let en = s2dc::Entity::from_rect_corners(
+                    x + bb.x as i32,
+                    y + bb.y as i32,
+                    x + bb.w as i32,
+                    y + bb.h as i32,
+                );
+                on_screen_tile_ents.push(TileColEn {
+                    col: en,
+                    platform: tdef.platform,
+                });
             });
             imm_dbg!(on_screen_tile_ents.len());
             self.game
@@ -146,7 +155,18 @@ impl App {
                 .move_y(self.game.player.vspeed, |player_en, off| {
                     let mut col = false;
                     for en in &on_screen_tile_ents {
-                        if player_en.would_collide(en, off) {
+                        if player_en.would_collide(&en.col, off) {
+                            if en.platform {
+                                if self.game.player.vspeed < 0. {
+                                    continue;
+                                }
+                                // If the player's feet are below the top of the platform,
+                                // collision shouldn't happen
+                                let player_feet = player_en.pos.y + player_en.bb.y;
+                                if player_feet > en.col.pos.y || self.game.player.down_intent {
+                                    continue;
+                                }
+                            }
                             col = true;
                             if self.game.player.vspeed > 0. {
                                 self.game.player.jumps_left = 1;
@@ -162,7 +182,10 @@ impl App {
                 .move_x(self.game.player.hspeed, |player_en, off| {
                     let mut col = false;
                     for en in &on_screen_tile_ents {
-                        if player_en.would_collide(en, off) {
+                        if en.platform {
+                            continue;
+                        }
+                        if player_en.would_collide(&en.col, off) {
                             col = true;
                             self.game.player.hspeed = 0.;
                         }
@@ -290,6 +313,12 @@ impl App {
     }
 }
 
+/// Tile collision entity for doing physics
+struct TileColEn {
+    col: s2dc::Entity,
+    platform: bool,
+}
+
 fn viewport_center_offset(rw_size: Vector2u, rt_size: Vector2u, scale: u8) -> ScreenVec {
     let rw_size = rw_size;
     let rt_size = rt_size * scale as u32;

src/game/player.rs

@@ -13,6 +13,8 @@ pub struct Player {
     pub vspeed: f32,
     pub hspeed: f32,
     pub jumps_left: u8,
+    /// true if the player wants to jump down from a platform
+    pub down_intent: bool,
 }
 
 fn inspect_mobile_entity(en: &mut MobileEntity, ui: &mut egui::Ui, _id_src: u64) {
@@ -32,6 +34,7 @@ impl Player {
             vspeed: 0.0,
             hspeed: 0.0,
             jumps_left: 0,
+            down_intent: false,
         }
     }
     #[allow(dead_code)]

src/tiles.rs

@@ -15,10 +15,27 @@ use crate::{
 
 #[derive(Serialize, Deserialize, Default, Debug, Inspect)]
 pub struct TileDef {
-    pub solid: bool,
+    pub bb: Option<TileBb>,
     /// Whether the tile emits light, and the light source offset
     pub light: Option<ScreenVec>,
     pub atlas_offset: AtlasOffset,
+    /// Platform behavior: Horizontally passable, vertically passable upwards
+    pub platform: bool,
+}
+
+const DEFAULT_TILE_BB: TileBb = TileBb {
+    x: 0,
+    y: 0,
+    w: TILE_SIZE,
+    h: TILE_SIZE,
+};
+
+#[derive(Serialize, Deserialize, Debug, Inspect, Clone, Copy)]
+pub struct TileBb {
+    pub x: u8,
+    pub y: u8,
+    pub w: u8,
+    pub h: u8,
 }
 
 #[derive(Serialize, Deserialize, Debug, Inspect)]
@@ -36,11 +53,12 @@ impl Default for TileDb {
 }
 
 const EMPTY: TileDef = TileDef {
-    solid: false,
+    bb: None,
     light: None,
     // Rendering empty tile is actually special cased, and no rendering is done.
     // But just in case, put the offset to UNKNOWN
     atlas_offset: UNKNOWN_ATLAS_OFF,
+    platform: false,
 };
 
 impl Index<TileId> for TileDb {
@@ -76,12 +94,13 @@ impl Default for AtlasOffset {
 const UNKNOWN_ATLAS_OFF: AtlasOffset = AtlasOffset { x: 320, y: 0 };
 
 static UNKNOWN_TILE: TileDef = TileDef {
-    solid: true,
+    bb: None,
     light: Some(ScreenVec {
         x: TILE_SIZE as ScreenSc / 2,
         y: TILE_SIZE as ScreenSc / 2,
     }),
     atlas_offset: UNKNOWN_ATLAS_OFF,
+    platform: false,
 };
 
 const PATH: &str = "tiles.dat";

src/tiles/tiledb_edit_ui.rs

@@ -3,7 +3,7 @@ use crate::{
     math::TILE_SIZE,
 };
 
-use super::TileDb;
+use super::{TileDb, DEFAULT_TILE_BB};
 
 pub fn tiledb_edit_ui(ctx: &egui::Context, tile_db: &mut TileDb) {
     egui::Window::new("Tiledb editor").show(ctx, |ui| {
@@ -30,6 +30,23 @@ pub fn tiledb_edit_ui(ctx: &egui::Context, tile_db: &mut TileDb) {
                             }
                         }
                     }
+                    match &mut def.bb {
+                        Some(bb) => {
+                            ui.label("x");
+                            ui.add(egui::DragValue::new(&mut bb.x));
+                            ui.label("y");
+                            ui.add(egui::DragValue::new(&mut bb.y));
+                            ui.label("w");
+                            ui.add(egui::DragValue::new(&mut bb.w));
+                            ui.label("h");
+                            ui.add(egui::DragValue::new(&mut bb.h));
+                        }
+                        None => {
+                            if ui.button("Insert bb").clicked() {
+                                def.bb = Some(DEFAULT_TILE_BB);
+                            }
+                        }
+                    }
                 }
             });
         ui.separator();