refactor(movement): generalize movement and use vectors

build.zig

@@ -25,6 +25,7 @@ pub fn build(b: *std.Build) void {
         "src/main.c",
         "src/map.c",
         "src/player.c",
+        "src/movement.c",
         "src/render.c",
         "src/rng.c",
         "src/settings.c",

src/common.h

@@ -4,6 +4,10 @@
 #include "settings.h"
 #include <raylib.h>
 
+typedef struct {
+  int x, y;
+} Vec2;
+
 // Tile types
 typedef enum { TILE_WALL, TILE_FLOOR, TILE_STAIRS } TileType;
 
@@ -57,7 +61,7 @@ typedef struct {
 
 // Player
 typedef struct {
-  int x, y;
+  Vec2 position;
   int hp, max_hp;
   int attack;
   int defense;
@@ -83,7 +87,7 @@ typedef enum { ENEMY_GOBLIN, ENEMY_SKELETON, ENEMY_ORC } EnemyType;
 
 // Enemy
 typedef struct {
-  int x, y;
+  Vec2 position;
   int hp;
   int max_hp;
   int attack;

src/enemy.c

@@ -2,6 +2,7 @@
 #include "combat.h"
 #include "common.h"
 #include "map.h"
+#include "movement.h"
 #include "rng.h"
 #include <string.h>
 
@@ -29,7 +30,7 @@ void enemy_spawn(Enemy enemies[], int *count, Map *map, Player *p, int floor) {
     get_random_floor_tile(map, &ex, &ey, 50);
 
     // Don't spawn on player position
-    if (ex == p->x && ey == p->y) {
+    if (ex == p->position.x && ey == p->position.y) {
       continue;
     }
 
@@ -41,8 +42,8 @@ void enemy_spawn(Enemy enemies[], int *count, Map *map, Player *p, int floor) {
     // Create enemy
     Enemy e;
     memset(&e, 0, sizeof(Enemy));
-    e.x = ex;
-    e.y = ey;
+    e.position.x = ex;
+    e.position.y = ey;
     e.alive = 1;
     e.type = rng_int(ENEMY_GOBLIN, max_type);
     e.effect_count = 0;
@@ -127,7 +128,7 @@ void enemy_spawn(Enemy enemies[], int *count, Map *map, Player *p, int floor) {
 // Check if position has an enemy
 int is_enemy_at(const Enemy *enemies, int count, int x, int y) {
   for (int i = 0; i < count; i++) {
-    if (enemies[i].alive && enemies[i].x == x && enemies[i].y == y) {
+    if (enemies[i].alive && enemies[i].position.x == x && enemies[i].position.y == y) {
       return 1;
     }
   }
@@ -136,45 +137,37 @@ int is_enemy_at(const Enemy *enemies, int count, int x, int y) {
 
 // Check if enemy can see player (adjacent)
 static int can_see_player(Enemy *e, Player *p) {
-  int dx = p->x - e->x;
-  int dy = p->y - e->y;
+  int dx = p->position.x - e->position.x;
+  int dy = p->position.y - e->position.y;
   return (dx >= -1 && dx <= 1 && dy >= -1 && dy <= 1);
 }
 
-// Check if position is occupied by player
-static int is_player_at(Player *p, int x, int y) {
-  return (p->x == x && p->y == y);
-}
 
 // Move enemy toward player
 static void enemy_move_toward_player(Enemy *e, Player *p, Map *map, Enemy *all_enemies, int enemy_count) {
   int dx = 0, dy = 0;
 
-  if (p->x > e->x)
+  if (p->position.x > e->position.x)
     dx = 1;
-  else if (p->x < e->x)
+  else if (p->position.x < e->position.x)
     dx = -1;
 
-  if (p->y > e->y)
+  if (p->position.y > e->position.y)
     dy = 1;
-  else if (p->y < e->y)
+  else if (p->position.y < e->position.y)
     dy = -1;
 
-  // Try horizontal first, then vertical
-  int new_x = e->x + dx;
-  int new_y = e->y;
+  Vec2 dir = {dx, 0};
+  if (dx != 0) {
+    MoveResult r = try_move_entity(&e->position, dir, map, p, all_enemies, enemy_count, false);
+    if (r == MOVE_RESULT_MOVED)
+      return;
+  }
 
-  if (dx != 0 && is_floor(map, new_x, new_y) && !is_enemy_at(all_enemies, enemy_count, new_x, new_y) &&
-      !is_player_at(p, new_x, new_y)) {
-    e->x = new_x;
-  } else if (dy != 0) {
-    new_x = e->x;
-    new_y = e->y + dy;
-    if (is_floor(map, new_x, new_y) && !is_enemy_at(all_enemies, enemy_count, new_x, new_y) &&
-        !is_player_at(p, new_x, new_y)) {
-      e->x = new_x;
-      e->y = new_y;
-    }
+  dir.x = 0;
+  dir.y = dy;
+  if (dy != 0) {
+    try_move_entity(&e->position, dir, map, p, all_enemies, enemy_count, false);
   }
 }
 

src/main.c

@@ -4,6 +4,7 @@
 #include "enemy.h"
 #include "items.h"
 #include "map.h"
+#include "movement.h"
 #include "player.h"
 #include "raylib.h"
 #include "render.h"
@@ -117,8 +118,8 @@ static void init_floor(GameState *gs, int floor_num) {
     gs->floors_reached = 1;
   } else {
     // Move player to new floor position
-    gs->player.x = start_x;
-    gs->player.y = start_y;
+    gs->player.position.x = start_x;
+    gs->player.position.y = start_y;
   }
   gs->player.floor = floor_num;
 
@@ -137,7 +138,8 @@ static void tick_all_effects(GameState *gs) {
   // Player effects
   int player_effect_dmg = combat_tick_effects(&gs->player);
   if (player_effect_dmg > 0) {
-    spawn_floating_text(gs, gs->player.x * TILE_SIZE + 8, gs->player.y * TILE_SIZE, player_effect_dmg, 0);
+    spawn_floating_text(gs, gs->player.position.x * TILE_SIZE + 8, gs->player.position.y * TILE_SIZE, player_effect_dmg,
+                        0);
     gs->screen_shake = SHAKE_EFFECT_DURATION;
   }
 
@@ -155,7 +157,7 @@ static void tick_all_effects(GameState *gs) {
       continue;
     int enemy_effect_dmg = combat_tick_enemy_effects(e);
     if (enemy_effect_dmg > 0) {
-      spawn_floating_text(gs, e->x * TILE_SIZE + 8, e->y * TILE_SIZE, enemy_effect_dmg, 0);
+      spawn_floating_text(gs, e->position.x * TILE_SIZE + 8, e->position.y * TILE_SIZE, enemy_effect_dmg, 0);
     }
     if (!e->alive) {
       add_log(gs, "Enemy died from effects!");
@@ -173,7 +175,7 @@ static void post_action(GameState *gs, Enemy *attacked_enemy) {
     return;
 
   // Check if stepped on stairs
-  if (gs->map.tiles[gs->player.y][gs->player.x] == TILE_STAIRS) {
+  if (gs->map.tiles[gs->player.position.y][gs->player.position.x] == TILE_STAIRS) {
     gs->awaiting_descend = 1;
     gs->last_message = "Descend to next floor? (Y/N)";
     gs->message_timer = 120;
@@ -182,8 +184,8 @@ static void post_action(GameState *gs, Enemy *attacked_enemy) {
 
   // combat feedback - player attacked an enemy this turn
   if (attacked_enemy != NULL) {
-    int ex = attacked_enemy->x * TILE_SIZE + 8;
-    int ey = attacked_enemy->y * TILE_SIZE;
+    int ex = attacked_enemy->position.x * TILE_SIZE + 8;
+    int ey = attacked_enemy->position.y * TILE_SIZE;
 
     if (combat_was_dodged()) {
       spawn_floating_label(gs, ex, ey, LABEL_DODGE, EFFECT_NONE);
@@ -224,8 +226,8 @@ static void post_action(GameState *gs, Enemy *attacked_enemy) {
     gs->screen_shake = SHAKE_PLAYER_DAMAGE_DURATION;
     gs->damage_taken += combat_get_last_damage();
     gs->times_hit++;
-    spawn_floating_text(gs, gs->player.x * TILE_SIZE + 8, gs->player.y * TILE_SIZE, combat_get_last_damage(),
-                        combat_was_critical());
+    spawn_floating_text(gs, gs->player.position.x * TILE_SIZE + 8, gs->player.position.y * TILE_SIZE,
+                        combat_get_last_damage(), combat_was_critical());
   }
 
   // Set message and check game over
@@ -388,7 +390,7 @@ static int handle_movement_input(GameState *gs) {
 
   // Check for manual item pickup (G key)
   if (IsKeyPressed(KEY_G)) {
-    Item *item = get_item_at_floor(gs->items, gs->item_count, gs->player.x, gs->player.y);
+    Item *item = get_item_at_floor(gs->items, gs->item_count, gs->player.position.x, gs->player.position.y);
     if (item != NULL) {
       if (player_pickup(&gs->player, item)) {
         gs->items_collected++;
@@ -417,38 +419,43 @@ static int handle_movement_input(GameState *gs) {
     }
   }
 
-  // Movement: use IsKeyDown for held-key repeat
-  int dx = 0, dy = 0;
-  if (IsKeyDown(KEY_W) || IsKeyDown(KEY_UP))
-    dy = -1;
-  else if (IsKeyDown(KEY_S) || IsKeyDown(KEY_DOWN))
-    dy = 1;
-  else if (IsKeyDown(KEY_A) || IsKeyDown(KEY_LEFT))
-    dx = -1;
-  else if (IsKeyDown(KEY_D) || IsKeyDown(KEY_RIGHT))
-    dx = 1;
 
-  if (dx == 0 && dy == 0)
+  Vec2 direction = {0, 0};
+  if (IsKeyDown(KEY_W) || IsKeyDown(KEY_UP))
+    direction.y = -1;
+  else if (IsKeyDown(KEY_S) || IsKeyDown(KEY_DOWN))
+    direction.y = 1;
+  else if (IsKeyDown(KEY_A) || IsKeyDown(KEY_LEFT))
+    direction.x = -1;
+  else if (IsKeyDown(KEY_D) || IsKeyDown(KEY_RIGHT))
+    direction.x = 1;
+
+  if (direction.x == 0 && direction.y == 0)
     return 0;
 
   // Reset combat event before player acts
   combat_reset_event();
 
-  int new_x = gs->player.x + dx;
-  int new_y = gs->player.y + dy;
+
+  int new_x = gs->player.position.x + direction.x;
+  int new_y = gs->player.position.y + direction.y;
+
+  Enemy *target = NULL;
   int action = 0;
 
-  // Attack enemy at target tile, or move into it
-  Enemy *target = player_find_enemy_at(gs->enemies, gs->enemy_count, new_x, new_y);
-  if (target != NULL) {
+  MoveResult result =
+      try_move_entity(&gs->player.position, direction, &gs->map, &gs->player, gs->enemies, gs->enemy_count, true);
+  if (result == MOVE_RESULT_MOVED) {
+    player_on_move(&gs->player);
+    action = 1;
+  } else if (result == MOVE_RESULT_BLOCKED_ENEMY) {
+    target = player_find_enemy_at(gs->enemies, gs->enemy_count, new_x, new_y);
     player_attack(&gs->player, target);
     action = 1;
-  } else {
-    action = player_move(&gs->player, dx, dy, &gs->map);
   }
 
   if (action)
-    post_action(gs, target);  // target is NULL on move, enemy ptr on attack
+    post_action(gs, target);
 
   return action;
 }

src/movement.c

@@ -0,0 +1,29 @@
+#include "movement.h"
+#include "enemy.h"
+#include "map.h"
+#include <stdbool.h>
+
+// Check if position is occupied by player
+static int is_player_at(Player *p, int x, int y) {
+  return (p->position.x == x && p->position.y == y);
+}
+
+MoveResult try_move_entity(Vec2 *p, Vec2 direction, Map *map, Player *player, Enemy *enemies, int enemy_count,
+                           bool moving_is_player) {
+  int new_x = p->x + direction.x;
+  int new_y = p->y + direction.y;
+
+  if (!is_floor(map, new_x, new_y))
+    return MOVE_RESULT_BLOCKED_WALL;
+
+  if (is_enemy_at(enemies, enemy_count, new_x, new_y))
+    return MOVE_RESULT_BLOCKED_ENEMY;
+  if (!moving_is_player) {
+    if (is_player_at(player, new_x, new_y))
+      return MOVE_RESULT_BLOCKED_PLAYER;
+  }
+
+  p->x = new_x;
+  p->y = new_y;
+  return MOVE_RESULT_MOVED;
+}

src/movement.h

@@ -0,0 +1,17 @@
+#ifndef MOVEMENT_H
+#define MOVEMENT_H
+
+#include "common.h"
+
+typedef enum {
+  MOVE_RESULT_MOVED,
+  MOVE_RESULT_BLOCKED_WALL,
+  MOVE_RESULT_BLOCKED_PLAYER,
+  MOVE_RESULT_BLOCKED_ENEMY
+} MoveResult;
+
+// Attempts to move entity in a given direction. Returns outcome of action.
+MoveResult try_move_entity(Vec2 *p, Vec2 direction, Map *map, Player *player, Enemy *enemies, int enemy_count,
+                           bool moving_is_player);
+
+#endif  // MOVEMENT_H

src/player.c

@@ -2,15 +2,13 @@
 #include "combat.h"
 #include "common.h"
 #include "items.h"
-#include "map.h"
+#include "movement.h"
 #include "settings.h"
-#include "utils.h"
-#include <stdlib.h>
 #include <string.h>
 
 void player_init(Player *p, int x, int y) {
-  p->x = x;
-  p->y = y;
+  p->position.x = x;
+  p->position.y = y;
   p->hp = PLAYER_BASE_HP;
   p->max_hp = PLAYER_BASE_HP;
   p->attack = PLAYER_BASE_ATTACK;
@@ -43,29 +41,18 @@ Enemy *player_find_enemy_at(Enemy *enemies, int count, int x, int y) {
   if (count > MAX_ENEMIES)
     count = MAX_ENEMIES;
   for (int i = 0; i < count; i++) {
-    if (enemies[i].alive && enemies[i].x == x && enemies[i].y == y)
+    if (enemies[i].alive && enemies[i].position.x == x && enemies[i].position.y == y)
       return &enemies[i];
   }
   return NULL;
 }
 
-int player_move(Player *p, int dx, int dy, Map *map) {
-  int new_x = p->x + dx;
-  int new_y = p->y + dy;
-
-  // Check bounds
-  if (!in_bounds(new_x, new_y, MAP_WIDTH, MAP_HEIGHT))
+int player_move(Player *p, Vec2 direction, Map *map, Enemy *enemies, int enemy_count) {
+  MoveResult result = try_move_entity(&p->position, direction, map, p, enemies, enemy_count, true);
+  if (result != MOVE_RESULT_MOVED)
     return 0;
 
-  // Check if walkable
-  if (!is_floor(map, new_x, new_y))
-    return 0;
-
-  // Move player
-  p->x = new_x;
-  p->y = new_y;
   p->step_count += 1;
-  // Regen suppressed while poisoned, bleeding, or burning
   if (p->step_count % REGEN_STEP_INTERVAL == 0 && p->hp < p->max_hp &&
       !combat_has_effect(p->effects, p->effect_count, EFFECT_POISON) &&
       !combat_has_effect(p->effects, p->effect_count, EFFECT_BLEED) &&
@@ -75,6 +62,16 @@ int player_move(Player *p, int dx, int dy, Map *map) {
   return 1;
 }
 
+void player_on_move(Player *p) {
+  p->step_count += 1;
+  if (p->step_count % REGEN_STEP_INTERVAL == 0 && p->hp < p->max_hp &&
+      !combat_has_effect(p->effects, p->effect_count, EFFECT_POISON) &&
+      !combat_has_effect(p->effects, p->effect_count, EFFECT_BLEED) &&
+      !combat_has_effect(p->effects, p->effect_count, EFFECT_BURN)) {
+    p->hp += 1;
+  }
+}
+
 void player_attack(Player *p, Enemy *e) {
   // Use combat system
   combat_player_attack(p, e);
@@ -228,8 +225,8 @@ int player_drop_item(Player *p, int inv_index, Item *items, int item_count) {
     if (items[i].picked_up) {
       // Place dropped item at this position
       items[i] = *item;
-      items[i].x = p->x;
-      items[i].y = p->y;
+      items[i].x = p->position.x;
+      items[i].y = p->position.y;
       items[i].picked_up = 0;
       // Remove from inventory
       player_remove_inventory_item(p, inv_index);

src/player.h

@@ -6,8 +6,8 @@
 // Initialize player at position
 void player_init(Player *p, int x, int y);
 
-// Move player to (x+dx, y+dy); returns 1 if moved, 0 if blocked
-int player_move(Player *p, int dx, int dy, Map *map);
+// Apply status effect, healing ect
+void player_on_move(Player *p);
 
 // Find a living enemy at tile (x, y); returns NULL if none
 Enemy *player_find_enemy_at(Enemy *enemies, int count, int x, int y);

src/render.c

@@ -30,7 +30,8 @@ void render_map(const Map *map) {
 }
 
 void render_player(const Player *p) {
-  Rectangle rect = {(float)(p->x * TILE_SIZE), (float)(p->y * TILE_SIZE), (float)TILE_SIZE, (float)TILE_SIZE};
+  Rectangle rect = {(float)(p->position.x * TILE_SIZE), (float)(p->position.y * TILE_SIZE), (float)TILE_SIZE,
+                    (float)TILE_SIZE};
   DrawRectangleRec(rect, BLUE);
 }
 
@@ -39,8 +40,8 @@ void render_enemies(const Enemy *enemies, int count) {
     if (!enemies[i].alive)
       continue;
 
-    Rectangle rect = {(float)(enemies[i].x * TILE_SIZE), (float)(enemies[i].y * TILE_SIZE), (float)TILE_SIZE,
-                      (float)TILE_SIZE};
+    Rectangle rect = {(float)(enemies[i].position.x * TILE_SIZE), (float)(enemies[i].position.y * TILE_SIZE),
+                      (float)TILE_SIZE, (float)TILE_SIZE};
 
     // Different colors based on enemy type
     Color enemy_color;
@@ -72,8 +73,8 @@ void render_enemies(const Enemy *enemies, int count) {
         bar_color = (Color){200, 180, 40, 255};  // yellow
       else
         bar_color = (Color){200, 60, 60, 255};  // red
-      Rectangle hp_bar = {(float)(enemies[i].x * TILE_SIZE), (float)(enemies[i].y * TILE_SIZE - 4), (float)hp_pixels,
-                          3};
+      Rectangle hp_bar = {(float)(enemies[i].position.x * TILE_SIZE), (float)(enemies[i].position.y * TILE_SIZE - 4),
+                          (float)hp_pixels, 3};
       DrawRectangleRec(hp_bar, bar_color);
     }
   }