Scrolling: internal scrolling value is rounded instead of truncated. (#6677)

docs/CHANGELOG.txt

@@ -55,6 +55,8 @@ Other changes:
 
 - Windows: BeginChild(): Fixed auto-resizing erroneously limiting size to host viewport
   minus padding. There are no limit to a child width/height. (#7063) [@Devyre]
+- Scrolling: internal scrolling value is rounded instead of truncated, as a way to reduce
+  speed asymetry when (incorrectly) attempting to scroll by non-integer amount. (#6677)
 - Nav, IO: SetNextFrameWantCaptureKeyboard(false) calls are not overrided back to true when
   navigation is enabled. SetNextFrameWantCaptureKeyboard() is always higher priority. (#6997)
 - Drag and Drop: Fixed drop target highlight on items temporarily pushing a widened clip rect

imgui.cpp

@@ -10122,7 +10122,7 @@ static ImVec2 CalcNextScrollFromScrollTargetAndClamp(ImGuiWindow* window)
             }
             scroll[axis] = scroll_target - center_ratio * (window->SizeFull[axis] - decoration_size[axis]);
         }
-        scroll[axis] = IM_TRUNC(ImMax(scroll[axis], 0.0f));
+        scroll[axis] = IM_ROUND(ImMax(scroll[axis], 0.0f));
         if (!window->Collapsed && !window->SkipItems)
             scroll[axis] = ImMin(scroll[axis], window->ScrollMax[axis]);
     }