pipe through left-over OS events to subsequent frames; do not drop them

src/df/gfx/df_gfx.c

@@ -10894,7 +10894,6 @@ df_gfx_init(OS_WindowRepaintFunctionType *window_repaint_entry_point, DF_StateDe
   Arena *arena = arena_alloc();
   df_gfx_state = push_array(arena, DF_GfxState, 1);
   df_gfx_state->arena = arena;
-  df_gfx_state->frame_arena = arena_alloc();
   df_gfx_state->num_frames_requested = 2;
   df_gfx_state->hist = hist;
   df_gfx_state->key_map_arena = arena_alloc();
@@ -10941,7 +10940,6 @@ internal void
 df_gfx_begin_frame(Arena *arena, DF_CmdList *cmds)
 {
   ProfBeginFunction();
-  arena_clear(df_gfx_state->frame_arena);
   df_gfx_state->hover_line_set_this_frame = 0;
 
   //- rjf: animate confirmation
@@ -11087,6 +11085,7 @@ df_gfx_begin_frame(Arena *arena, DF_CmdList *cmds)
               arena_release(ws->hover_eval_arena);
               arena_release(ws->arena);
               SLLStackPush(df_gfx_state->free_window, ws);
+              ws->gen += 1;
             }
           }
         }break;

src/df/gfx/df_gfx.h

@@ -662,7 +662,6 @@ struct DF_GfxState
 {
   // rjf: arenas
   Arena *arena;
-  Arena *frame_arena;
 
   // rjf: frame request state
   U64 num_frames_requested;

src/os/gfx/os_gfx.c

@@ -189,3 +189,35 @@ os_text(OS_EventList *events, OS_Handle window, U32 character)
   }
   return result;
 }
+
+internal OS_EventList
+os_event_list_copy(Arena *arena, OS_EventList *src)
+{
+  OS_EventList dst = {0};
+  for(OS_Event *s = src->first; s != 0; s = s->next)
+  {
+    OS_Event *d = push_array(arena, OS_Event, 1);
+    MemoryCopyStruct(d, s);
+    d->strings = str8_list_copy(arena, &s->strings);
+    DLLPushBack(dst.first, dst.last, d);
+    dst.count += 1;
+  }
+  return dst;
+}
+
+internal void
+os_event_list_concat_in_place(OS_EventList *dst, OS_EventList *to_push)
+{
+  if(dst->last && to_push->first)
+  {
+    dst->last->next = to_push->first;
+    to_push->first->prev = dst->last;
+    dst->last = to_push->last;
+    dst->count += to_push->count;
+  }
+  else if(!dst->last && to_push->first)
+  {
+    MemoryCopyStruct(dst, to_push);
+  }
+  MemoryZeroStruct(to_push);
+}

src/os/gfx/os_gfx.h

@@ -92,6 +92,8 @@ internal void os_eat_event(OS_EventList *events, OS_Event *event);
 internal B32  os_key_press(OS_EventList *events, OS_Handle window, OS_EventFlags flags, OS_Key key);
 internal B32  os_key_release(OS_EventList *events, OS_Handle window, OS_EventFlags flags, OS_Key key);
 internal B32  os_text(OS_EventList *events, OS_Handle window, U32 character);
+internal OS_EventList os_event_list_copy(Arena *arena, OS_EventList *src);
+internal void os_event_list_concat_in_place(OS_EventList *dst, OS_EventList *to_push);
 
 ////////////////////////////////
 //~ rjf: @os_hooks Main Initialization API (Implemented Per-OS)

src/os/gfx/win32/os_gfx_win32.c

@@ -114,6 +114,7 @@ w32_push_event(OS_EventKind kind, W32_Window *window)
   result->kind = kind;
   result->window = os_window_from_w32_window(window);
   result->flags = os_get_event_flags();
+  w32_event_list.count += 1;
   return(result);
 }
 

src/raddbg/raddbg.c

@@ -65,7 +65,10 @@ update_and_render(OS_Handle repaint_window_handle, void *user_data)
   OS_EventList events = {0};
   if(os_handle_match(repaint_window_handle, os_handle_zero()))
   {
-    events = os_get_events(scratch.arena, df_gfx_state->num_frames_requested == 0);
+    OS_EventList leftover_events_copy = os_event_list_copy(scratch.arena, &leftover_events);
+    OS_EventList new_events = os_get_events(scratch.arena, df_gfx_state->num_frames_requested == 0);
+    os_event_list_concat_in_place(&events, &leftover_events_copy);
+    os_event_list_concat_in_place(&events, &new_events);
   }
 
   //- rjf: enable txti change detection
@@ -296,6 +299,13 @@ update_and_render(OS_Handle repaint_window_handle, void *user_data)
     }
   }
 
+  //- rjf: gather leftover events for subsequent frame
+  if(events.count != 0)
+  {
+    arena_clear(leftover_events_arena);
+    leftover_events = os_event_list_copy(leftover_events_arena, &events);
+  }
+
   //- rjf: determine frame time, record into history
   U64 end_time_us = os_now_microseconds();
   U64 frame_time_us = end_time_us-begin_time_us;
@@ -404,6 +414,9 @@ entry_point(int argc, char **argv)
       IPCInfo *ipc_info = (IPCInfo *)ipc_shared_memory_base;
       ipc_info->msg_size = 0;
 
+      //- rjf: set up leftover event arena
+      leftover_events_arena = arena_alloc();
+
       //- rjf: initialize stuff we depend on
       {
         hs_init();

src/raddbg/raddbg.h

@@ -482,6 +482,8 @@ read_only global String8 ipc_shared_memory_name = str8_lit_comp("_raddbg_ipc_sha
 read_only global String8 ipc_semaphore_name = str8_lit_comp("_raddbg_ipc_semaphore_");
 global U64 frame_time_us_history[64] = {0};
 global U64 frame_time_us_history_idx = 0;
+global Arena *leftover_events_arena = 0;
+global OS_EventList leftover_events = {0};
 
 ////////////////////////////////
 //~ rjf: Frontend Entry Points