Nav: Fixed an issue with Gamepad navigation when the movement lead to a scroll and frame time > repeat rate. (#6171)

docs/CHANGELOG.txt

@@ -51,6 +51,9 @@ Other changes:
   allowing to press buttons with Enter. (#5606)
   (Enter emulates a "prefer text input" activation vs.
    Space emulates a "prefer tweak" activation which is to closer to gamepad controls).
+- Nav: Fixed an issue with Gamepad navigation when the movement lead to a scroll and
+  frame time > repeat rate. Triggering a new move request on the same frame as a move
+  result lead to an incorrect calculation and loss of navigation id. (#6171)
 - Drag and Drop: Fixed handling of overlapping targets when smaller one is submitted
   before and can accept the same data type. (#6183).
 - Drag and Drop: Clear drag and drop state as soon as delivery is accepted in order to

imgui.cpp

@@ -11262,16 +11262,21 @@ void ImGui::NavUpdateCreateMoveRequest()
     }
 
     // When using gamepad, we project the reference nav bounding box into window visible area.
-    // This is to allow resuming navigation inside the visible area after doing a large amount of scrolling, since with gamepad all movements are relative
-    // (can't focus a visible object like we can with the mouse).
+    // This is to allow resuming navigation inside the visible area after doing a large amount of scrolling,
+    // since with gamepad all movements are relative (can't focus a visible object like we can with the mouse).
     if (g.NavMoveSubmitted && g.NavInputSource == ImGuiInputSource_Gamepad && g.NavLayer == ImGuiNavLayer_Main && window != NULL)// && (g.NavMoveFlags & ImGuiNavMoveFlags_Forwarded))
     {
         bool clamp_x = (g.NavMoveFlags & (ImGuiNavMoveFlags_LoopX | ImGuiNavMoveFlags_WrapX)) == 0;
         bool clamp_y = (g.NavMoveFlags & (ImGuiNavMoveFlags_LoopY | ImGuiNavMoveFlags_WrapY)) == 0;
         ImRect inner_rect_rel = WindowRectAbsToRel(window, ImRect(window->InnerRect.Min - ImVec2(1, 1), window->InnerRect.Max + ImVec2(1, 1)));
+
+        // Take account of changing scroll to handle triggering a new move request on a scrolling frame. (#6171)
+        // Otherwise 'inner_rect_rel' would be off on the move result frame.
+        inner_rect_rel.Translate(CalcNextScrollFromScrollTargetAndClamp(window) - window->Scroll);
+
         if ((clamp_x || clamp_y) && !inner_rect_rel.Contains(window->NavRectRel[g.NavLayer]))
         {
-            //IMGUI_DEBUG_LOG_NAV("[nav] NavMoveRequest: clamp NavRectRel for gamepad move\n");
+            IMGUI_DEBUG_LOG_NAV("[nav] NavMoveRequest: clamp NavRectRel for gamepad move\n");
             float pad_x = ImMin(inner_rect_rel.GetWidth(), window->CalcFontSize() * 0.5f);
             float pad_y = ImMin(inner_rect_rel.GetHeight(), window->CalcFontSize() * 0.5f); // Terrible approximation for the intent of starting navigation from first fully visible item
             inner_rect_rel.Min.x = clamp_x ? (inner_rect_rel.Min.x + pad_x) : -FLT_MAX;