wasm app

src/app/app_wasm.c

@@ -1,13 +1,51 @@
+/*
+
+.doesn't miss events (always processes all key strokes and buttons etc.)
+.replayable / deterministic (that is you can serialize all the events, replay them back and get the same results)
+..rendering and update decoupled
+.sleeps properly when nothing is happening
+.animations probably then should be in the rendering part
+
+void app_update(app_event_t *events, i32 event_count) {
+    loop (events) update(it);
+
+    {
+        app_event_t *ev = events + event_count - 1;
+        f64 delta_time = app_anim_get_delta_time();
+        f64 time       = app_anim_get_time();
+        animate(ev, delta_time, time);
+        render(ev);
+    }
+}
+
+while (true) {
+    app_event_t *events = NULL;
+    if (animating) {
+        events = poll_events(); // non-blocking
+    } else {
+        events = wait_for_events(); // blocking
+    }
+    app_update(events, event_count);
+
+    SwapBuffers(); // vsync block
+}
+
+*/
+
 glb_wasm_export char wasm_temp_buff1[128] = {[127] = 0x13};
 glb_wasm_export i32  wasm_temp_buff1_len  = 127;
 glb_wasm_export char wasm_temp_buff2[128] = {[127] = 0x13};
 glb_wasm_export i32  wasm_temp_buff2_len  = 127;
 
-glb    f64                    wasm_dpr;
-glb    ma_arena_t            *wasm_input_text_arena;
-glb    STACK(app_event_t, 64) wasm_events;
-glb    b32                    wasm_event_failed_to_queue;
-glb    f64                    wasm_last_time = 0;
+global f64                    wasm_dpr;
+global ma_arena_t            *wasm_input_text_arena;
+global STACK(app_event_t, 64) wasm_events;
+global b32                    wasm_event_failed_to_queue;
+
+global f64                    wasm_delta_time;
+global f64                    wasm_time;
+global f64                    wasm_last_time_milliseconds;
+global f64                    wasm_app_init_time_milliseconds;
 
 typedef struct wasm_cached_t wasm_cached_t;
 struct wasm_cached_t {
@@ -141,10 +179,12 @@ fn_wasm_export void wasm_key_up(char *key, b32 ctrl, b32 shift, b32 alt, b32 met
     }
 }
 
-fn_wasm_export void wasm_update(f64 time, f64 width, f64 height, f64 dpr) {
-    f64 delta_time = (time - wasm_last_time);
-    v2f64_t window_size = (v2f64_t){width / dpr, height / dpr};
+fn_wasm_export void wasm_update(f64 width, f64 height, f64 dpr) {
+    wasm_time = os_get_milliseconds();
+    wasm_delta_time = wasm_time - wasm_last_time_milliseconds;
 
+    v2f64_t window_size = (v2f64_t){width / dpr, height / dpr};
+    wasm_dpr = dpr;
 
     if (wasm_events.len == 0) {
         wasm_add_event((app_event_t){
@@ -160,15 +200,12 @@ fn_wasm_export void wasm_update(f64 time, f64 width, f64 height, f64 dpr) {
     for (i32 i = 0; i < wasm_events.len; i += 1) {
         wasm_events.data[i].dpr = dpr;
         wasm_events.data[i].window_size = window_size;
-        wasm_events.data[i].time = time;
-        wasm_events.data[i].delta_time = delta_time;
     }
-    wasm_dpr = dpr;
 
     app_update(wasm_events.data, wasm_events.len);
 
     wasm_events.len = 0;
-    wasm_last_time = time;
+    wasm_last_time_milliseconds = wasm_time;
     ma_set0(wasm_input_text_arena);
 }
 
@@ -176,4 +213,13 @@ fn_wasm_export void wasm_init(void) {
     core_init();
     wasm_input_text_arena = ma_push_arena(&tcx.perm, kib(1));
     app_init();
+    wasm_app_init_time_milliseconds = os_get_milliseconds();
+}
+
+fn f64 app_get_anim_time(void) {
+    return wasm_time;
+}
+
+fn f64 app_get_anim_delta_time(void) {
+    return wasm_delta_time;
 }