demo 1

src/entities/cargo/log.rs

@@ -0,0 +1,64 @@
+//! Log cargo spawning — called when a tree is felled.
+//!
+//! Each trunk tile that was removed becomes a Cargo log entity placed on
+//! that tile. Logs are Haulable — dorfs pick them up into their HaulSlot.
+//!
+//! The log sprite reuses the trunk sprite (texture ID 500004) as a
+//! placeholder until a dedicated ground-log sprite exists.
+
+use bevy::prelude::*;
+
+use crate::constants::PIXEL_RATIO;
+use crate::entities::cargo::{Cargo, Haulable};
+use crate::entities::item::constants::ITEM_Z_FIGHTING_OFFSET;
+use crate::entities::item::inventory::constants::SIZE_LARGE;
+use crate::world::tiles::TileMap;
+
+/// Weight of a single log in kg. Enough to encumber a dorf carrying one.
+pub const LOG_WEIGHT_KG: u32 = 15;
+
+/// Spawn a Cargo log entity at `tile_pos` and register it in cargo_tiles.
+///
+/// If the tile is already occupied (another log landed here), finds the
+/// nearest free tile via TileMap::find_nearest_free_cargo_tile.
+///
+/// Returns the spawned Entity, or None if no free tile found within radius.
+pub fn spawn_log_cargo(
+    commands: &mut Commands,
+    tilemap: &mut TileMap,
+    tile_pos: IVec3,
+    log_sprite: Handle<Image>,
+) -> Option<Entity> {
+    // Find a free tile — the exact trunk position may be occupied
+    let drop_pos = tilemap.find_nearest_free_cargo_tile(tile_pos, 4)?;
+
+    let entity = commands
+        .spawn((
+            Cargo {
+                tile_pos: drop_pos,
+                name: "log",
+                weight: LOG_WEIGHT_KG,
+                size: SIZE_LARGE,
+                ground_sprite: log_sprite.clone(),
+            },
+            Haulable,
+            Sprite {
+                image: log_sprite.clone(),
+                ..Default::default()
+            },
+            Transform::from_translation(Vec3::new(
+                drop_pos.x as f32,
+                drop_pos.y as f32,
+                drop_pos.z as f32 + ITEM_Z_FIGHTING_OFFSET,
+            ))
+            .with_scale(Vec3::splat(PIXEL_RATIO)),
+            Visibility::Visible,
+        ))
+        .id();
+
+    tilemap
+        .place_cargo(drop_pos, entity)
+        .expect("place_cargo failed after find_nearest_free_cargo_tile succeeded");
+
+    Some(entity)
+}

src/entities/cargo/mod.rs

@@ -1,8 +1,10 @@
 pub mod components;
+pub mod log;
 pub mod systems;
 
 pub use crate::world::tiles::tilemap::CargoPlaceError;
 pub use components::{Cargo, CarryVisualState, HaulSlot, Haulable};
+pub use log::spawn_log_cargo;
 pub use systems::{any_hauling, carry_visual_system, haul_encumbrance_system};
 
 pub use crate::plugins::cargo::CargoPlugin;