Overlays: Reduce memory footprint and load time (#18577)

- Point to existing image when the overlay cfg reuses a path
- `images` array in `input_overlay_t` holds unique `texture_image`s

Author: neil4

input/input_driver.c

@@ -3018,6 +3018,20 @@ void input_overlay_set_alpha_mod(
    }
 }
 
+static void input_overlay_free_images(input_overlay_t *ol)
+{
+   size_t i;
+
+   if (!ol || !ol->images)
+      return;
+
+   for (i = 0; i < ol->num_images; i++)
+      image_texture_free(ol->images[i]);
+
+   free(ol->images);
+   ol->images = NULL;
+}
+
 static void input_overlay_free_overlays(input_overlay_t *ol)
 {
    size_t i;
@@ -3041,7 +3055,6 @@ void input_overlay_free_overlay(struct overlay *overlay)
 
    for (i = 0; i < overlay->size; i++)
    {
-      image_texture_free(&overlay->descs[i].image);
       if (overlay->descs[i].eightway_config)
          free(overlay->descs[i].eightway_config);
       overlay->descs[i].eightway_config = NULL;
@@ -3053,7 +3066,6 @@ void input_overlay_free_overlay(struct overlay *overlay)
    if (overlay->descs)
       free(overlay->descs);
    overlay->descs       = NULL;
-   image_texture_free(&overlay->image);
 }
 
 /**
@@ -3067,6 +3079,8 @@ static void input_overlay_free(input_overlay_t *ol)
    if (!ol)
       return;
 
+   input_overlay_free_images(ol);
+
    input_overlay_free_overlays(ol);
 
    if (ol->iface && ol->iface->enable)
@@ -5415,6 +5429,25 @@ void input_overlay_check_mouse_cursor(void)
    }
 }
 
+static void input_overlay_loaded_move_images(input_overlay_t *ol,
+      struct string_list *image_list)
+{
+   size_t i;
+
+   ol->images = malloc(ol->num_images * sizeof(struct texture_image *));
+
+   if (!ol->images)
+   {
+      for (i = 0; i < ol->num_images; i++)
+         image_texture_free(image_list->elems[i].attr.p);
+      ol->num_images = 0;
+      RARCH_ERR("[Overlay] Couldn't allocate images array.\n");
+   }
+
+   for (i = 0; i < ol->num_images; i++)
+      ol->images[i] = (struct texture_image*)image_list->elems[i].attr.p;
+}
+
 /* task_data = overlay_task_data_t* */
 static void input_overlay_loaded(retro_task_t *task,
       void *task_data, void *user_data, const char *err)
@@ -5436,6 +5469,7 @@ static void input_overlay_loaded(retro_task_t *task,
    ol->size        = data->size;
    ol->active      = data->active;
    ol->path        = data->overlay_path;
+   ol->num_images  = data->image_list->size;
    ol->next_index  = (unsigned)((ol->index + 1) % ol->size);
    ol->flags      |= INPUT_OVERLAY_ALIVE;
    if (data->flags & OVERLAY_LOADER_IS_OSK)
@@ -5444,6 +5478,10 @@ static void input_overlay_loaded(retro_task_t *task,
    overlay_types   = data->overlay_types;
 #endif
 
+   if (ol->num_images > 0)
+      input_overlay_loaded_move_images(ol, data->image_list);
+   string_list_free(data->image_list);
+
    free(data);
 
    /* Due to the asynchronous nature of overlay loading

input/input_overlay.h

@@ -384,7 +384,9 @@ struct input_overlay
    const video_overlay_interface_t *iface;
    input_overlay_state_t overlay_state;
    input_overlay_pointer_state_t pointer_state;
+   struct texture_image **images;
 
+   size_t num_images;
    size_t index;
    size_t size;
 
@@ -435,6 +437,7 @@ typedef struct
    char *overlay_path;
    struct overlay *overlays;
    struct overlay *active;
+   struct string_list *image_list;
    size_t size;
    uint16_t overlay_types;
    uint8_t flags;

libretro-common/include/lists/string_list.h

@@ -59,7 +59,7 @@ struct string_list
  *
  * Searches for an element (@elem) inside the string list.
  *
- * @return Number of elements found, otherwise 0.
+ * @return 1-based index if element could be found, otherwise 0.
  */
 int string_list_find_elem(const struct string_list *list, const char *elem);
 

tasks/task_overlay.c

@@ -40,6 +40,7 @@ struct overlay_loader
    char *overlay_path;
    struct overlay *overlays;
    struct overlay *active;
+   struct string_list *image_list;
 
    size_t resolve_pos;
    unsigned size;
@@ -62,10 +63,41 @@ static void task_overlay_image_done(struct overlay *overlay)
    overlay->pos_increment = (overlay->size / 2) ? ((unsigned)(overlay->size / 2)) : 8;
 }
 
+static bool task_overlay_load_image_texture(
+      overlay_loader_t *loader,
+      struct overlay *overlay,
+      struct texture_image *image,
+      const char *full_path,
+      const char *rel_path)
+{
+   int img_idx = string_list_find_elem(loader->image_list, rel_path) - 1;
+
+   /* Load image if unique. Copy existing texture_image if not */
+   if (img_idx == -1)
+   {
+      union string_list_elem_attr attr;
+
+      image->supports_rgba =
+            (loader->flags & OVERLAY_LOADER_RGBA_SUPPORT) ? true : false;
+
+      if (!image_texture_load(image, full_path))
+         return false;
+
+      attr.p = (void*)image;
+      string_list_append(loader->image_list, rel_path, attr);
+   }
+   else
+      *image = *((struct texture_image*)loader->image_list->elems[img_idx].attr.p);
+
+   overlay->load_images[overlay->load_images_size++] = *image;
+
+   return true;
+}
+
 static void task_overlay_load_desc_image(
       overlay_loader_t *loader,
       struct overlay_desc *desc,
-      struct overlay *input_overlay,
+      struct overlay *overlay,
       unsigned ol_idx, unsigned desc_idx)
 {
    char overlay_desc_image_key[32];
@@ -81,22 +113,16 @@ static void task_overlay_load_desc_image(
    if (config_get_path(conf, overlay_desc_image_key,
             image_path, sizeof(image_path)))
    {
-      struct texture_image image_tex;
       char path[PATH_MAX_LENGTH];
       fill_pathname_resolve_relative(path, loader->overlay_path,
             image_path, sizeof(path));
 
-      image_tex.supports_rgba = (loader->flags & OVERLAY_LOADER_RGBA_SUPPORT) ? true : false;
-
-      if (image_texture_load(&image_tex, path))
-      {
-         input_overlay->load_images[input_overlay->load_images_size++] = image_tex;
-         desc->image       = image_tex;
-         desc->image_index = input_overlay->load_images_size - 1;
-      }
+      if (task_overlay_load_image_texture(loader, overlay, &desc->image,
+               path, image_path))
+         desc->image_index = overlay->load_images_size - 1;
    }
 
-   input_overlay->pos ++;
+   overlay->pos ++;
 }
 
 static void task_overlay_redefine_eightway_direction(
@@ -781,7 +807,6 @@ static void task_overlay_deferred_load(retro_task_t *task)
 
       if (!string_is_empty(overlay->config.paths.path))
       {
-         struct texture_image image_tex;
          char overlay_resolved_path[PATH_MAX_LENGTH];
 
          overlay_resolved_path[0] = '\0';
@@ -790,19 +815,14 @@ static void task_overlay_deferred_load(retro_task_t *task)
                loader->overlay_path,
                overlay->config.paths.path, sizeof(overlay_resolved_path));
 
-         image_tex.supports_rgba =
-               (loader->flags & OVERLAY_LOADER_RGBA_SUPPORT) ? true : false;
-
-         if (!image_texture_load(&image_tex, overlay_resolved_path))
+         if (!task_overlay_load_image_texture(loader, overlay, &overlay->image,
+               overlay_resolved_path, overlay->config.paths.path))
          {
             RARCH_ERR("[Overlay] Failed to load image: \"%s\".\n",
                   overlay_resolved_path);
             loader->loading_status = OVERLAY_IMAGE_TRANSFER_ERROR;
             goto error;
          }
-
-         overlay->load_images[overlay->load_images_size++] = image_tex;
-         overlay->image = image_tex;
       }
 
       config_get_array(conf, overlay->config.names.key,
@@ -1008,19 +1028,16 @@ static void task_overlay_free(retro_task_t *task)
 {
    unsigned i;
    overlay_loader_t *loader  = (overlay_loader_t*)task->state;
-   struct overlay *overlay   = &loader->overlays[loader->pos];
    uint8_t flg               = task_get_flags(task);
 
    if ((flg & RETRO_TASK_FLG_CANCELLED) > 0)
    {
       if (loader->overlay_path)
          free(loader->overlay_path);
 
-      for (i = 0; i < overlay->load_images_size; i++)
-      {
-         struct texture_image *ti = &overlay->load_images[i];
-         image_texture_free(ti);
-      }
+      for (i = 0; i < loader->image_list->size; i++)
+         image_texture_free(loader->image_list->elems[i].attr.p);
+      string_list_free(loader->image_list);
 
       for (i = 0; i < loader->size; i++)
          input_overlay_free_overlay(&loader->overlays[i]);
@@ -1074,6 +1091,7 @@ static void task_overlay_handler(retro_task_t *task)
       data->flags                       = loader->flags;
       data->overlay_types               = loader->overlay_types;
       data->overlay_path                = loader->overlay_path;
+      data->image_list                  = loader->image_list;
 
       task_set_data(task, data);
    }
@@ -1096,9 +1114,10 @@ bool task_push_overlay_load_default(
       void *user_data)
 {
    task_finder_data_t find_data;
-   retro_task_t *t          = NULL;
-   config_file_t *conf      = NULL;
-   overlay_loader_t *loader = NULL;
+   retro_task_t *t                = NULL;
+   config_file_t *conf            = NULL;
+   overlay_loader_t *loader       = NULL;
+   struct string_list *image_list = NULL;
 
    if (string_is_empty(overlay_path))
       return false;
@@ -1115,9 +1134,18 @@ bool task_push_overlay_load_default(
    if (!loader)
       return false;
 
+   image_list               = string_list_new();
+
+   if (!image_list)
+   {
+      free(loader);
+      return false;
+   }
+
    if (!(conf = config_file_new_from_path_to_string(overlay_path)))
    {
       free(loader);
+      free(image_list);
       return false;
    }
 
@@ -1126,6 +1154,7 @@ bool task_push_overlay_load_default(
       /* Error - overlays variable not defined in config. */
       config_file_free(conf);
       free(loader);
+      free(image_list);
       return false;
    }
 
@@ -1136,10 +1165,12 @@ bool task_push_overlay_load_default(
    {
       config_file_free(conf);
       free(loader);
+      free(image_list);
       return false;
    }
 
    loader->conf             = conf;
+   loader->image_list       = image_list;
    loader->state            = OVERLAY_STATUS_DEFERRED_LOAD;
    loader->pos_increment    = (loader->size / 4) ? (loader->size / 4) : 4;
 
@@ -1157,6 +1188,7 @@ bool task_push_overlay_load_default(
       config_file_free(conf);
       free(loader->overlays);
       free(loader);
+      free(image_list);
       return false;
    }