From 9586f78c56577bc70ff191b7a6037879c5038317 Mon Sep 17 00:00:00 2001
From: Holger Schemel <holger.schemel@virtion.de>
Date: Mon, 9 Dec 2024 19:21:06 +0100
Subject: [PATCH] fixed (and added warning when) trying to free already freed
 textures

---
 src/libgame/sdl.c | 15 +++++++++++++++
 src/libgame/sdl.h |  2 ++
 2 files changed, 17 insertions(+)

diff --git a/src/libgame/sdl.c b/src/libgame/sdl.c
index 4c485263..8bb732ab 100644
--- a/src/libgame/sdl.c
+++ b/src/libgame/sdl.c
@@ -554,6 +554,9 @@ void SDLCreateBitmapTextures(Bitmap *bitmap)
 
   bitmap->texture        = SDLCreateTextureFromSurface(bitmap->surface);
   bitmap->texture_masked = SDLCreateTextureFromSurface(bitmap->surface_masked);
+
+  // store renderer used to create textures
+  bitmap->renderer = sdl_renderer;
 }
 
 void SDLFreeBitmapSurfaces(Bitmap *bitmap)
@@ -575,6 +578,18 @@ void SDLFreeBitmapTextures(Bitmap *bitmap)
   if (bitmap == NULL)
     return;
 
+  // check renderer used to create textures
+  if (bitmap->renderer != NULL &&
+      bitmap->renderer != sdl_renderer &&
+      (bitmap->texture != NULL || bitmap->texture_masked != NULL))
+  {
+    // if renderer was destroyed, all its textures were also destroyed
+    bitmap->texture = NULL;
+    bitmap->texture_masked = NULL;
+
+    Warn("trying to free textures already freed by destroying renderer!");
+  }
+
   if (bitmap->texture)
     SDL_DestroyTexture(bitmap->texture);
   if (bitmap->texture_masked)
diff --git a/src/libgame/sdl.h b/src/libgame/sdl.h
index 23eb13ca..c2b55c24 100644
--- a/src/libgame/sdl.h
+++ b/src/libgame/sdl.h
@@ -83,6 +83,8 @@ struct SDLSurfaceInfo
   SDL_Surface *surface_masked;
   SDL_Texture *texture;
   SDL_Texture *texture_masked;
+
+  SDL_Renderer *renderer;	// renderer used to create textures
 };
 
 struct MouseCursorInfo
-- 
2.34.1