Popups: Fix b17b2fb (#4936)

imgui.cpp

@@ -6073,6 +6073,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
  {
  // Initialize
  const bool window_is_child_tooltip = (flags & ImGuiWindowFlags_ChildWindow) && (flags & ImGuiWindowFlags_Tooltip); // FIXME-WIP: Undocumented behavior of Child+Tooltip for pinned tooltip (#1345)
+ const bool window_just_appearing_after_hidden_for_resize = (window->HiddenFramesCannotSkipItems > 0);
  window->Active = true;
  window->HasCloseButton = (p_open != NULL);
  window->ClipRect = ImVec4(-FLT_MAX, -FLT_MAX, +FLT_MAX, +FLT_MAX);
@@ -6234,6 +6235,8 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
  SetWindowPos(window, window->SetWindowPosVal - window->Size * window->SetWindowPosPivot, 0); // Position given a pivot (e.g. for centering)
  else if ((flags & ImGuiWindowFlags_ChildMenu) != 0)
  window->Pos = FindBestWindowPosForPopup(window);
+ else if ((flags & ImGuiWindowFlags_Popup) != 0 && !window_pos_set_by_api && window_just_appearing_after_hidden_for_resize)
+ window->Pos = FindBestWindowPosForPopup(window);
  else if ((flags & ImGuiWindowFlags_Tooltip) != 0 && !window_pos_set_by_api && !window_is_child_tooltip)
  window->Pos = FindBestWindowPosForPopup(window);
 
@@ -9417,6 +9420,10 @@ ImVec2 ImGui::FindBestWindowPosForPopup(ImGuiWindow* window)
  r_avoid = ImRect(parent_window->Pos.x + horizontal_overlap, -FLT_MAX, parent_window->Pos.x + parent_window->Size.x - horizontal_overlap - parent_window->ScrollbarSizes.x, FLT_MAX);
  return FindBestWindowPosForPopupEx(window->Pos, window->Size, &window->AutoPosLastDirection, r_outer, r_avoid, ImGuiPopupPositionPolicy_Default);
  }
+ if (window->Flags & ImGuiWindowFlags_Popup)
+ {
+ return FindBestWindowPosForPopupEx(window->Pos, window->Size, &window->AutoPosLastDirection, r_outer, ImRect(window->Pos, window->Pos), ImGuiPopupPositionPolicy_Default); // Ideally we'd disable r_avoid here
+ }
  if (window->Flags & ImGuiWindowFlags_Tooltip)
  {
  // Position tooltip (always follows mouse)