add MLT_PLACEBO_CACHE_PATH and replace atext()

Author: ddennedy

src/modules/placebo/factory.c

@@ -1,6 +1,6 @@
 /*
  * factory.c -- module registration for libplacebo filters
- * Copyright (C) 2025 D-Ogi
+ * Copyright (C) 2025-2026 D-Ogi
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

src/modules/placebo/filter_placebo_render.c

@@ -1,6 +1,6 @@
 /*
  * filter_placebo_render.c -- GPU-accelerated renderer via libplacebo
- * Copyright (C) 2025 D-Ogi
+ * Copyright (C) 2025-2026 D-Ogi
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

src/modules/placebo/filter_placebo_render.yml

@@ -3,7 +3,7 @@ type: filter
 identifier: placebo.render
 title: GPU Render (libplacebo)
 version: 1
-copyright: Copyright (C) 2025 D-Ogi
+copyright: Copyright (C) 2025-2026 D-Ogi
 creator: D-Ogi
 license: LGPLv2.1
 language: en
@@ -13,6 +13,9 @@ description: >
   GPU-accelerated scaling, debanding, dithering and tonemapping via libplacebo.
   Uses D3D11 on Windows, Vulkan elsewhere. Processes every frame through
   pl_renderer with configurable quality presets and scaling algorithms.
+  The compiled shader cache is stored in a platform-specific location and can
+  be overridden by setting the MLT_PLACEBO_CACHE_PATH environment variable to
+  an absolute path for the cache file.
 
 parameters:
   - identifier: preset

src/modules/placebo/filter_placebo_shader.c

@@ -1,6 +1,6 @@
 /*
  * filter_placebo_shader.c -- custom .hook shader loader via libplacebo
- * Copyright (C) 2025 D-Ogi
+ * Copyright (C) 2025-2026 D-Ogi
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

src/modules/placebo/filter_placebo_shader.yml

@@ -3,7 +3,7 @@ type: filter
 identifier: placebo.shader
 title: GPU Shader (libplacebo)
 version: 1
-copyright: Copyright (C) 2025 D-Ogi
+copyright: Copyright (C) 2025-2026 D-Ogi
 creator: D-Ogi
 license: LGPLv2.1
 language: en
@@ -13,6 +13,9 @@ description: >
   Load and apply a custom mpv/libplacebo .hook shader file for GPU-accelerated
   video processing. Supports Anime4K, FSRCNNX, film grain, and other
   mpv-compatible user shaders. The shader file is hot-reloaded when modified.
+  The compiled shader cache is stored in a platform-specific location and can
+  be overridden by setting the MLT_PLACEBO_CACHE_PATH environment variable to
+  an absolute path for the cache file.
 
 parameters:
   - identifier: shader_path

src/modules/placebo/gpu_context.c

@@ -1,6 +1,6 @@
 /*
  * gpu_context.c -- shared libplacebo GPU lifecycle (singleton)
- * Copyright (C) 2025 D-Ogi
+ * Copyright (C) 2025-2026 D-Ogi
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -19,6 +19,7 @@
 
 #include "gpu_context.h"
 
+#include <framework/mlt_factory.h>
 #include <framework/mlt_frame.h>
 #include <libplacebo/cache.h>
 #include <libplacebo/dispatch.h>
@@ -103,6 +104,11 @@ static pthread_mutex_t s_render_mutex = PTHREAD_MUTEX_INITIALIZER;
 
 static void get_cache_path(char *buf, size_t len)
 {
+    const char *override = getenv("MLT_PLACEBO_CACHE_PATH");
+    if (override && override[0] != '\0') {
+        snprintf(buf, len, "%s", override);
+        return;
+    }
 #ifdef _WIN32
     char appdata[MAX_PATH] = {0};
     if (SUCCEEDED(SHGetFolderPathA(NULL, CSIDL_APPDATA, NULL, 0, appdata))) {
@@ -305,7 +311,7 @@ static int init_gpu(void)
 
     load_cache();
 
-    atexit(placebo_gpu_release);
+    mlt_factory_register_for_clean_up(NULL, (mlt_destructor) placebo_gpu_release);
 
     return 1;
 }

src/modules/placebo/gpu_context.h

@@ -1,6 +1,6 @@
 /*
  * gpu_context.h -- shared libplacebo GPU lifecycle
- * Copyright (C) 2025 D-Ogi
+ * Copyright (C) 2025-2026 D-Ogi
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public