ScrollToItem: amend fully visible tests to take account of spacing used (fix nav in one axis scrolling back and forth between axises when space is tight by just < ItemSpacing*2) (#3692, #2812, #4242, #2900)

Amend 8f495e55

imgui.cpp

@@ -6164,7 +6164,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
         // Inner rectangle
         // Not affected by window border size. Used by:
         // - InnerClipRect
-        // - ScrollToBringRectIntoView()
+        // - ScrollToRectEx()
         // - NavUpdatePageUpPageDown()
         // - Scrollbar()
         window->InnerRect.Min.x = window->Pos.x;
@@ -8042,8 +8042,8 @@ ImVec2 ImGui::ScrollToRectEx(ImGuiWindow* window, const ImRect& item_rect, ImGui
 
     const bool fully_visible_x = item_rect.Min.x >= window_rect.Min.x && item_rect.Max.x <= window_rect.Max.x;
     const bool fully_visible_y = item_rect.Min.y >= window_rect.Min.y && item_rect.Max.y <= window_rect.Max.y;
-    const bool can_be_fully_visible_x = item_rect.GetWidth() <= window_rect.GetWidth();
-    const bool can_be_fully_visible_y = item_rect.GetHeight() <= window_rect.GetHeight();
+    const bool can_be_fully_visible_x = (item_rect.GetWidth() + g.Style.ItemSpacing.x * 2.0f) <= window_rect.GetWidth();
+    const bool can_be_fully_visible_y = (item_rect.GetHeight() + g.Style.ItemSpacing.y * 2.0f) <= window_rect.GetHeight();
 
     if ((flags & ImGuiScrollFlags_KeepVisibleEdgeX) && !fully_visible_x)
     {