Engine: minimal stage

fgeo.c

@@ -0,0 +1,114 @@
+#include "fgeo.h"
+#include <furi.h>
+#include <gui/gui.h>
+#include <input/input.h>
+
+#include "clock_timer.h"
+
+GameEngineSettings game_engine_settings_init() {
+    GameEngineSettings settings;
+    settings.fps = 60.0f;
+    settings.show_fps = false;
+    return settings;
+}
+
+struct GameEngine {
+    Gui* gui;
+    FuriPubSub* input_pubsub;
+    FuriThreadId thread_id;
+    GameEngineSettings settings;
+    volatile bool running;
+};
+
+typedef enum {
+    GameThreadFlagUpdate = 1 << 0,
+    GameThreadFlagStop = 1 << 1,
+} GameThreadFlag;
+
+#define GameThreadFlagMask (GameThreadFlagUpdate | GameThreadFlagStop)
+
+static void clock_timer_tick(void* context) {
+    GameEngine* engine = context;
+    furi_thread_flags_set(engine->thread_id, GameThreadFlagUpdate);
+}
+
+static void input_events_callback(const void* value, void* context) {
+    GameEngine* engine = context;
+
+    const InputEvent* event = value;
+    if(event->key == InputKeyBack && event->type == InputTypePress) {
+        furi_thread_flags_set(engine->thread_id, GameThreadFlagStop);
+    }
+}
+
+GameEngine* game_engine_alloc(GameEngineSettings settings) {
+    GameEngine* engine = malloc(sizeof(GameEngine));
+    engine->gui = furi_record_open(RECORD_GUI);
+    engine->input_pubsub = furi_record_open(RECORD_INPUT_EVENTS);
+    engine->thread_id = furi_thread_get_current_id();
+    engine->settings = settings;
+    engine->running = false;
+
+    return engine;
+}
+
+void game_engine_free(GameEngine* engine) {
+    furi_record_close(RECORD_GUI);
+    furi_record_close(RECORD_INPUT_EVENTS);
+    free(engine);
+}
+
+static void canvas_printf(Canvas* canvas, uint8_t x, uint8_t y, const char* format, ...) {
+    FuriString* string = furi_string_alloc();
+    va_list args;
+    va_start(args, format);
+    furi_string_vprintf(string, format, args);
+    va_end(args);
+
+    canvas_draw_str(canvas, x, y, furi_string_get_cstr(string));
+
+    furi_string_free(string);
+}
+
+void game_engine_run(GameEngine* engine) {
+    engine->running = true;
+    Canvas* canvas = gui_direct_draw_acquire(engine->gui);
+    FuriPubSubSubscription* input_subscription =
+        furi_pubsub_subscribe(engine->input_pubsub, input_events_callback, engine);
+
+    clock_timer_init(clock_timer_tick, engine, engine->settings.fps);
+    clock_timer_start();
+
+    uint32_t time_start = DWT->CYCCNT;
+
+    while(true) {
+        uint32_t flags =
+            furi_thread_flags_wait(GameThreadFlagMask, FuriFlagWaitAny, FuriWaitForever);
+        furi_check((flags & FuriFlagError) == 0);
+
+        if(flags & GameThreadFlagUpdate) {
+            canvas_reset(canvas);
+
+            uint32_t time_end = DWT->CYCCNT;
+            uint32_t time_delta = time_end - time_start;
+            time_start = time_end;
+
+            if(engine->settings.show_fps) {
+                float fps = 1.0f / (time_delta / (float)SystemCoreClock);
+                canvas_set_color(canvas, ColorXOR);
+                canvas_printf(canvas, 0, 7, "%u", (uint32_t)roundf(fps));
+            }
+
+            canvas_commit(canvas);
+        } else if(flags & GameThreadFlagStop) {
+            break;
+        }
+    }
+
+    clock_timer_stop();
+    clock_timer_deinit();
+
+    gui_direct_draw_release(engine->gui);
+    furi_pubsub_unsubscribe(engine->input_pubsub, input_subscription);
+    engine->running = false;
+}

fgeo.h

@@ -0,0 +1,25 @@
+#pragma once
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+    float fps;
+    bool show_fps;
+} GameEngineSettings;
+
+GameEngineSettings game_engine_settings_init();
+
+typedef struct GameEngine GameEngine;
+
+GameEngine* game_engine_alloc(GameEngineSettings settings);
+
+void game_engine_run(GameEngine* engine);
+
+void game_engine_free(GameEngine* engine);
+
+#ifdef __cplusplus
+}
+#endif