npc layers support

src/npc/ai/misc.rs

@@ -4,7 +4,7 @@ use crate::caret::CaretType;
 use crate::common::{Direction, Rect};
 use crate::framework::error::GameResult;
 use crate::npc::list::NPCList;
-use crate::npc::NPC;
+use crate::npc::{NPC, NPCLayer};
 use crate::player::Player;
 use crate::rng::RNG;
 use crate::shared_game_state::SharedGameState;
@@ -495,6 +495,7 @@ impl NPC {
     pub(crate) fn tick_n041_busted_door(&mut self, state: &mut SharedGameState) -> GameResult {
         if self.action_num == 0 {
             self.action_num = 1;
+            self.layer = NPCLayer::Background;
             self.anim_rect = state.constants.npc.n041_busted_door;
             self.y -= 16 * 0x200;
         }

src/npc/mod.rs

@@ -49,6 +49,14 @@ bitfield! {
   pub show_damage, set_show_damage: 15; // 0x8000
 }
 
+#[derive(Debug, Copy, Clone, Eq, PartialOrd, PartialEq)]
+#[repr(u8)]
+pub enum NPCLayer {
+    Background = 0,
+    Middleground = 1,
+    Foreground = 2,
+}
+
 /// Represents an NPC object.
 #[derive(Debug, Clone)]
 #[repr(C)]
@@ -72,6 +80,7 @@ pub struct NPC {
     /// Previous Y position, used by frame interpolator
     pub prev_y: i32,
     pub exp: u16,
+    pub layer: NPCLayer,
     pub size: u8,
     pub shock: u16,
     pub life: u16,
@@ -115,6 +124,7 @@ impl NPC {
             prev_x: 0,
             prev_y: 0,
             exp: 0,
+            layer: NPCLayer::Middleground,
             size: 0,
             shock: 0,
             life: 0,
@@ -140,6 +150,14 @@ impl NPC {
             rng: Xoroshiro32PlusPlus::new(0),
         }
     }
+
+    pub fn draw_if_layer(&self, state: &mut SharedGameState, ctx: &mut Context, frame: &Frame, layer: NPCLayer) -> GameResult {
+        if self.layer == layer {
+            self.draw(state, ctx, frame)?
+        }
+
+        Ok(())
+    }
 }
 
 impl GameEntity<([&mut Player; 2], &NPCList, &mut Stage, &BulletManager)> for NPC {

src/npc/utils.rs

@@ -6,7 +6,7 @@ use crate::weapon::bullet::Bullet;
 use crate::caret::CaretType;
 use crate::common::{Condition, Direction, Flag, Rect};
 use crate::map::NPCData;
-use crate::npc::{NPC, NPCFlag, NPCTable};
+use crate::npc::{NPC, NPCFlag, NPCTable, NPCLayer};
 use crate::npc::list::NPCList;
 use crate::player::Player;
 use crate::rng::{RNG, Xoroshiro32PlusPlus};
@@ -61,6 +61,7 @@ impl NPC {
             event_num: 0,
             shock: 0,
             exp,
+            layer: NPCLayer::Middleground,
             size,
             life,
             damage,

src/scene/game_scene.rs

@@ -22,7 +22,7 @@ use crate::input::touch_controls::TouchControlType;
 use crate::inventory::{Inventory, TakeExperienceResult};
 use crate::npc::boss::BossNPC;
 use crate::npc::list::NPCList;
-use crate::npc::NPC;
+use crate::npc::{NPC, NPCLayer};
 use crate::physics::PhysicalEntity;
 use crate::player::{Player, TargetPlayer};
 use crate::rng::XorShift;
@@ -212,6 +212,28 @@ impl GameScene {
         Ok(())
     }
 
+    fn draw_npc_layer(&self,  state: &mut SharedGameState, ctx: &mut Context, layer: NPCLayer) -> GameResult {
+        for npc in self.npc_list.iter_alive() {
+            if npc.layer != layer || npc.x < (self.frame.x - 128 * 0x200 - npc.display_bounds.width() as i32 * 0x200)
+                || npc.x
+                > (self.frame.x
+                + 128 * 0x200
+                + (state.canvas_size.0 as i32 + npc.display_bounds.width() as i32) * 0x200)
+                && npc.y < (self.frame.y - 128 * 0x200 - npc.display_bounds.height() as i32 * 0x200)
+                || npc.y
+                > (self.frame.y
+                + 128 * 0x200
+                + (state.canvas_size.1 as i32 + npc.display_bounds.height() as i32) * 0x200)
+            {
+                continue;
+            }
+
+            npc.draw(state, ctx, &self.frame)?;
+        }
+
+        Ok(())
+    }
+
     fn draw_bullets(&self, state: &mut SharedGameState, ctx: &mut Context) -> GameResult {
         let batch = state.texture_set.get_or_load_batch(ctx, &state.constants, "Bullet")?;
         let mut x: i32;
@@ -1552,6 +1574,7 @@ impl Scene for GameScene {
         //graphics::set_canvas(ctx, Some(&state.game_canvas));
         self.draw_background(state, ctx)?;
         self.draw_tiles(state, ctx, TileLayer::Background)?;
+        self.draw_npc_layer(state, ctx, NPCLayer::Background)?;
         if state.settings.shader_effects
             && self.stage.data.background_type != BackgroundType::Black
             && self.stage.data.background_type != BackgroundType::Outside
@@ -1562,23 +1585,7 @@ impl Scene for GameScene {
         }
 
         self.boss.draw(state, ctx, &self.frame)?;
-        for npc in self.npc_list.iter_alive() {
-            if npc.x < (self.frame.x - 128 * 0x200 - npc.display_bounds.width() as i32 * 0x200)
-                || npc.x
-                    > (self.frame.x
-                        + 128 * 0x200
-                        + (state.canvas_size.0 as i32 + npc.display_bounds.width() as i32) * 0x200)
-                    && npc.y < (self.frame.y - 128 * 0x200 - npc.display_bounds.height() as i32 * 0x200)
-                || npc.y
-                    > (self.frame.y
-                        + 128 * 0x200
-                        + (state.canvas_size.1 as i32 + npc.display_bounds.height() as i32) * 0x200)
-            {
-                continue;
-            }
-
-            npc.draw(state, ctx, &self.frame)?;
-        }
+        self.draw_npc_layer(state, ctx, NPCLayer::Middleground)?;
         self.draw_bullets(state, ctx)?;
         self.player2.draw(state, ctx, &self.frame)?;
         self.player1.draw(state, ctx, &self.frame)?;