Allow plugins to not have to define all plugin functions.

1 files changed, 26 insertions, 31 deletions

diff --git a/gltfview/src/game.c b/gltfview/src/game.c
index 7470f75..d618447 100644
--- a/gltfview/src/game.c
+++ b/gltfview/src/game.c
@@ -31,19 +31,6 @@
 // Plugin to load if no plugin is provided.
 static const char* DEFAULT_PLUGIN = "texture_view";
 
-static bool validate_plugin(const Plugin* plugin) {
-#define CHECK_FUNCTION(name, signature)           \
-  if (!plugin_resolve(plugin, signature, name)) { \
-    LOGE("Plugin is missing function: " #name);   \
-    return false;                                 \
-  }
-  CHECK_FUNCTION("init", plugin_init);
-  CHECK_FUNCTION("boot", plugin_boot);
-  CHECK_FUNCTION("update", plugin_update);
-  CHECK_FUNCTION("render", plugin_render);
-  return true;
-}
-
 bool game_new(Game* game, int argc, const char** argv) {
   assert(game);
 
@@ -76,9 +63,6 @@ bool game_new(Game* game, int argc, const char** argv) {
   if (!(game->plugin = load_plugin(game->plugin_engine, plugin))) {
     goto cleanup;
   }
-  if (!validate_plugin(game->plugin)) {
-    goto cleanup;
-  }
 
   if (!(game->gfx = gfx_init())) {
     goto cleanup;
@@ -90,16 +74,21 @@ bool game_new(Game* game, int argc, const char** argv) {
     goto cleanup;
   }
 
-  void* plugin_state = plugin_call(game->plugin, plugin_init, "init", game);
-  if (!plugin_state) {
-    goto cleanup;
+  if (plugin_resolve(game->plugin, plugin_init, "init")) {
+    void* plugin_state = plugin_call(game->plugin, plugin_init, "init", game);
+    if (!plugin_state) {
+      goto cleanup;
+    }
+    set_plugin_state(game->plugin, plugin_state);
   }
-  set_plugin_state(game->plugin, plugin_state);
 
-  bool boot_success =
-      plugin_call(game->plugin, plugin_boot, "boot", plugin_state, game);
-  if (!boot_success) {
-    goto cleanup;
+  if (plugin_resolve(game->plugin, plugin_boot, "boot")) {
+    void* plugin_state = get_plugin_state(game->plugin);
+    bool  boot_success =
+        plugin_call(game->plugin, plugin_boot, "boot", plugin_state, game);
+    if (!boot_success) {
+      goto cleanup;
+    }
   }
 
   return true;
@@ -125,15 +114,19 @@ void game_end(Game* game) {
 
 void game_update(Game* game, double t, double dt) {
   plugin_engine_update(game->plugin_engine);
-  if (plugin_reloaded(game->plugin)) {
+  if (plugin_reloaded(game->plugin) &&
+      plugin_resolve(game->plugin, plugin_init, "init")) {
     void* plugin_state = plugin_call(game->plugin, plugin_init, "init", game);
     assert(plugin_state); // TODO: handle error better.
     set_plugin_state(game->plugin, plugin_state);
   }
 
-  void* plugin_state = get_plugin_state(game->plugin);
-  assert(plugin_state);
-  plugin_call(game->plugin, plugin_update, "update", plugin_state, game, t, dt);
+  if (plugin_resolve(game->plugin, plugin_update, "update")) {
+    // Plugin state may be null if plugin does not expose init().
+    void* plugin_state = get_plugin_state(game->plugin);
+    plugin_call(
+        game->plugin, plugin_update, "update", plugin_state, game, t, dt);
+  }
 }
 
 void game_render(const Game* game) {
@@ -144,9 +137,11 @@ void game_render(const Game* game) {
       &(RenderSceneParams){
           .mode = RenderDefault, .scene = game->scene, .camera = game->camera});
 
-  void* plugin_state = get_plugin_state(game->plugin);
-  assert(plugin_state);
-  plugin_call(game->plugin, plugin_render, "render", plugin_state, game);
+  if (plugin_resolve(game->plugin, plugin_render, "render")) {
+    // Plugin state may be null if plugin does not expose init().
+    void* plugin_state = get_plugin_state(game->plugin);
+    plugin_call(game->plugin, plugin_render, "render", plugin_state, game);
+  }
 }
 
 void game_set_viewport(Game* game, int width, int height) {