From 1215746e050cefa9a918c97aefe96e3590016e87 Mon Sep 17 00:00:00 2001
From: En Yi <en.yi@tutanota.com>
Date: Tue, 6 Aug 2024 20:36:23 +0800
Subject: [PATCH] Add x-flipping for anchoring

---
 engine/assets.c       | 35 +++++++++++++++++++++++++++--------
 engine/assets.h       |  2 +-
 scenes/editor_scene.c |  7 +++++--
 scenes/player_ent.c   |  3 +--
 4 files changed, 34 insertions(+), 13 deletions(-)

diff --git a/engine/assets.c b/engine/assets.c
index 53d148a..c803aaa 100644
--- a/engine/assets.c
+++ b/engine/assets.c
@@ -575,15 +575,8 @@ void draw_sprite_pro(Sprite_t* spr, int frame_num, Vector2 pos, float rotation,
     );
 }
 
-Vector2 shift_bbox(Vector2 bbox, Vector2 new_bbox, AnchorPoint_t anchor)
-{
-    Vector2 p1 = get_anchor_offset(bbox, anchor);
-    Vector2 p2 = get_anchor_offset(new_bbox, anchor);
 
-    return Vector2Subtract(p1, p2);
-}
-
-Vector2 get_anchor_offset(Vector2 bbox, AnchorPoint_t anchor)
+static Vector2 internal_get_anchor_offset(Vector2 bbox, AnchorPoint_t anchor)
 {
     Vector2 offset = {0};
     switch (anchor)
@@ -624,4 +617,30 @@ Vector2 get_anchor_offset(Vector2 bbox, AnchorPoint_t anchor)
     return offset;
 }
 
+Vector2 shift_bbox(Vector2 bbox, Vector2 new_bbox, AnchorPoint_t anchor)
+{
+    Vector2 p1 = internal_get_anchor_offset(bbox, anchor);
+    Vector2 p2 = internal_get_anchor_offset(new_bbox, anchor);
 
+    return Vector2Subtract(p1, p2);
+}
+
+Vector2 get_anchor_offset(Vector2 bbox, AnchorPoint_t anchor, bool flip_x)
+{
+    if (flip_x)
+    {
+        switch(anchor)
+        {
+            case AP_TOP_LEFT: anchor = AP_TOP_RIGHT; break;
+            case AP_TOP_RIGHT: anchor = AP_TOP_LEFT; break;
+            case AP_MID_LEFT: anchor = AP_MID_RIGHT; break;
+            case AP_MID_RIGHT: anchor = AP_MID_LEFT; break;
+            case AP_BOT_LEFT: anchor = AP_BOT_RIGHT; break;
+            case AP_BOT_RIGHT: anchor = AP_BOT_LEFT; break;
+            default:
+            break;
+        }
+    }
+
+    return internal_get_anchor_offset(bbox, anchor);
+}
diff --git a/engine/assets.h b/engine/assets.h
index 43e5459..ab50a87 100644
--- a/engine/assets.h
+++ b/engine/assets.h
@@ -83,7 +83,7 @@ LevelPack_t* get_level_pack(Assets_t* assets, const char* name);
 
 void draw_sprite(Sprite_t* spr, int frame_num, Vector2 pos, float rotation, bool flip_x);
 void draw_sprite_pro(Sprite_t* spr, int frame_num, Vector2 pos, float rotation, uint8_t flip, Vector2 scale, Color colour);
-Vector2 get_anchor_offset(Vector2 bbox, AnchorPoint_t anchor);
+Vector2 get_anchor_offset(Vector2 bbox, AnchorPoint_t anchor, bool flip_x);
 Vector2 shift_bbox(Vector2 bbox, Vector2 new_bbox, AnchorPoint_t anchor);
 
 typedef struct SFX
diff --git a/scenes/editor_scene.c b/scenes/editor_scene.c
index 7f9f401..b8d82ac 100644
--- a/scenes/editor_scene.c
+++ b/scenes/editor_scene.c
@@ -438,12 +438,15 @@ static void render_editor_game_scene(Scene_t* scene)
                     {
                         pos = Vector2Add(
                             pos,
-                            get_anchor_offset(p_bbox->size, spr.dest_anchor)
+                            get_anchor_offset(p_bbox->size, spr.dest_anchor, p_cspr->flip_x)
                         );
                         pos = Vector2Subtract(pos, spr.src_anchor);
                     }
 
-                    pos = Vector2Add(pos, spr.offset);
+                    Vector2 offset = spr.offset;
+                    if (p_cspr->flip_x) offset.x *= -1;
+
+                    pos = Vector2Add(pos, offset);
                     draw_sprite(spr.sprite, p_cspr->current_frame, pos, 0.0f, p_cspr->flip_x);
                 }
             }
diff --git a/scenes/player_ent.c b/scenes/player_ent.c
index 4b4b964..7f61446 100644
--- a/scenes/player_ent.c
+++ b/scenes/player_ent.c
@@ -176,8 +176,7 @@ static bool init_player_file(FILE* in_file, Assets_t* assets)
         player_sprite_map[i].sprite = spr;
         //player_sprite_map[i].offset = offset;
         player_sprite_map[i].offset = (Vector2){0};
-        player_sprite_map[i].src_anchor = spr->frame_size;
-        player_sprite_map[i].src_anchor.x /= 2.0f;
+        player_sprite_map[i].src_anchor = get_anchor_offset(spr->frame_size, AP_BOT_CENTER, false);
         player_sprite_map[i].dest_anchor = AP_BOT_CENTER;
         i++;
     }