1 files changed, 216 insertions, 0 deletions

diff --git a/game/src/game.c b/game/src/game.c
new file mode 100644
index 0000000..64be4f3
--- /dev/null
+++ b/game/src/game.c
@@ -0,0 +1,216 @@
+/*
+ * Main game module with entry point and game loop.
+ *
+ * The game module sets up the window and GL context and defers the core game
+ * logic to a plugin.
+ */
+#define _GNU_SOURCE 200112L // For readlink()
+
+#include "game.h"
+
+#include "plugins/plugin.h"
+
+#include <gfx/gfx.h>
+#include <gfx/gfx_app.h>
+#include <gfx/render_backend.h>
+#include <gfx/renderer.h>
+#include <gfx/scene/camera.h>
+#include <gfx/scene/node.h>
+#include <gfx/scene/object.h>
+#include <gfx/scene/scene.h>
+
+#include <error.h>
+#include <log/log.h>
+#include <math/camera.h>
+#include <plugin.h>
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <linux/limits.h>
+
+#include <unistd.h>
+
+#undef _GNU_SOURCE
+
+static const int WIDTH   = 1350;
+static const int HEIGHT  = 900;
+static const int MAX_FPS = 60;
+
+/// Initialize the game's plugin.
+static bool init_plugin(Game* game) {
+  assert(game);
+  assert(game->plugin);
+  // Plugin state is allowed to be null, either when the plugin does not
+  // expose an init() or when init() does not initialize a state.
+  if (plugin_resolve(game->plugin, plugin_init, "init")) {
+    State* plugin_state = 0;
+    if (!plugin_call(game->plugin, plugin_init, "init", game, &plugin_state)) {
+      return false;
+    }
+    set_plugin_state(game->plugin, plugin_state);
+  }
+  return true; // Plugin does not need to expose an init().
+}
+
+/// Shutdown the game's plugin.
+/// The game's plugin is allowed to be null in the call to this function.
+static void shutdown_plugin(Game* game) {
+  assert(game);
+  if (game->plugin &&
+      (plugin_resolve(game->plugin, plugin_shutdown, "shutdown"))) {
+    void* plugin_state = get_plugin_state(game->plugin);
+    plugin_call(game->plugin, plugin_shutdown, "shutdown", game, plugin_state);
+    set_plugin_state(game->plugin, 0);
+  }
+}
+
+/// Boot the game's plugin.
+static bool boot_plugin(Game* game) {
+  assert(game);
+  assert(game->plugin);
+  if (plugin_resolve(game->plugin, plugin_boot, "boot")) {
+    void* plugin_state = get_plugin_state(game->plugin);
+    return plugin_call(game->plugin, plugin_boot, "boot", game, plugin_state);
+  }
+  return true; // Plugin does not need to expose a boot().
+}
+
+/// Update the plugin's state.
+static void update_plugin(Game* game, double t, double dt) {
+  assert(game);
+  assert(game->plugin);
+  if (plugin_resolve(game->plugin, plugin_update, "update")) {
+    void* plugin_state = get_plugin_state(game->plugin);
+    plugin_call(
+        game->plugin, plugin_update, "update", game, plugin_state, t, dt);
+  }
+}
+
+/// Plugin render.
+static void render_plugin(const Game* game) {
+  assert(game);
+  assert(game->plugin);
+  if (plugin_resolve(game->plugin, plugin_render, "render")) {
+    void* plugin_state = get_plugin_state(game->plugin);
+    plugin_call(game->plugin, plugin_render, "render", game, plugin_state);
+  }
+}
+
+/// Plugin resize.
+static void resize_plugin(Game* game, int width, int height) {
+  assert(game);
+  assert(game->plugin);
+  if (plugin_resolve(game->plugin, plugin_resize, "resize")) {
+    void* plugin_state = get_plugin_state(game->plugin);
+    plugin_call(
+        game->plugin, plugin_resize, "resize", game, plugin_state, width,
+        height);
+  }
+}
+
+void app_end(Game* game);
+
+bool app_init(const GfxAppDesc* desc, void** app_state) {
+  assert(desc);
+
+  if (desc->argc <= 1) {
+    LOGE("Usage: %s <plugin> [plugin args]", desc->argv[0]);
+    return false;
+  }
+
+  Game* game = calloc(1, sizeof(Game));
+  if (!game) {
+    LOGE("Failed to allocate game state");
+    return false;
+  }
+
+  // Syntax: game <plugin> [plugin args]
+  //
+  // Here we consume the <plugin> arg so that plugins receive the remainder
+  // args starting from 0.
+  game->argc = desc->argc - 1;
+  game->argv = desc->argv + 1;
+
+  char exe_path_buf[NAME_MAX] = {0};
+  if (readlink("/proc/self/exe", exe_path_buf, sizeof(exe_path_buf)) == -1) {
+    LOGE("readlink(/proc/self/exe) failed");
+    goto cleanup;
+  }
+
+  // Replace the last / with a null terminator to remove the exe file from the
+  // path. This gets the file's parent directory.
+  *strrchr(exe_path_buf, '/') = 0;
+
+  const mstring exe_dir      = mstring_make(exe_path_buf);
+  const mstring plugins_path = mstring_concat_cstr(exe_dir, "/src/plugins");
+
+  if (!(game->plugin_engine = new_plugin_engine(
+            &(PluginEngineDesc){.plugins_dir = mstring_cstr(&plugins_path)}))) {
+    goto cleanup;
+  }
+
+  const char* plugin = desc->argv[1];
+  if (!(game->plugin = load_plugin(game->plugin_engine, plugin))) {
+    goto cleanup;
+  }
+
+  if (!(game->gfx = gfx_init())) {
+    goto cleanup;
+  }
+
+  if (!init_plugin(game)) {
+    goto cleanup;
+  }
+  if (!boot_plugin(game)) {
+    goto cleanup;
+  }
+
+  *app_state = game;
+  return true;
+
+cleanup:
+  LOGE("Gfx error: %s", get_error());
+  app_end(game);
+  return false;
+}
+
+void app_end(Game* game) {
+  assert(game);
+  shutdown_plugin(game);
+  if (game->gfx) {
+    gfx_destroy(&game->gfx);
+  }
+  if (game->plugin) {
+    delete_plugin(&game->plugin);
+  }
+  if (game->plugin_engine) {
+    delete_plugin_engine(&game->plugin_engine);
+  }
+}
+
+void app_update(Game* game, double t, double dt) {
+  plugin_engine_update(game->plugin_engine);
+  if (plugin_reloaded(game->plugin)) {
+    shutdown_plugin(game);
+    const bool result = init_plugin(game);
+    assert(result); // TODO: handle error better.
+  }
+
+  update_plugin(game, t, dt);
+}
+
+void app_render(const Game* game) {
+  RenderBackend* render_backend = gfx_get_render_backend(game->gfx);
+  gfx_start_frame(render_backend);
+  render_plugin(game);
+  gfx_end_frame(render_backend);
+}
+
+void app_resize(Game* game, int width, int height) {
+  resize_plugin(game, width, height);
+}
+
+GFX_APP_MAIN(WIDTH, HEIGHT, MAX_FPS);