Doc: Update docs for split view

- Described using the new viewport modes in 3D.
- Some changes to terminology.

Fixes: QDS-15390
Change-Id: I7d08ab34cb16e548d48dc7b0128fee1d722fd3b8
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>

doc/qtdesignstudio/src/qtquick3d-editor/qtdesignstudio-3d-editor.qdoc

@@ -125,25 +125,27 @@
     Use the split view to view the scene from different points of view using the different
     viewport modes.
 
+    Use the split view to split the \uicontrol 3D view into multiple viewports. You can
+    manipulate each of the viewports separately.
+
     To view the scene in a split view, select \imagesplitview (\uicontrol {Show Viewport Modes})
     and then select one of the viewport modes:
     \list
-        \li The \uicontrol Single mode shows the scene in one pane from a single point of view.
-        \li The \uicontrol Quad mode shows the scene from four different points of view using
-            four panes.
+        \li The \uicontrol Single mode shows the scene in a single viewport.
+        \li The \uicontrol Quad mode shows the scene from four different viewports.
         \li The \uicontrol {3 Left 1 Right} mode shows the scene from four points of
-            view using three smaller and one larger pane.
-        \li The \uicontrol {2 Horizontal} mode shows the scene from two points of view using
-            two horizontal panes.
-        \li The \uicontrol {2 Vertical} mode shows the scene from two points of view using
-            two vertical panes.
+            view using three smaller and one larger viewport.
+        \li The \uicontrol {2 Horizontal} mode shows the scene from two horizontal
+            viewports.
+        \li The \uicontrol {2 Vertical} mode shows the scene from two vertical viewports.
     \endlist
 
-    Select one of the panes to make it the active pane. The active pane is marked with a blue frame.
-    Use the world axis helper to change the point of view for each pane independently. You can
-    \l {Toggling the camera mode}{toggle the camera mode} between the perspective and orthographic
-    modes independently for each pane. \l {Navigating in the 3D scene}{Navigate} each split by
-    panning, rotating, and zooming. To resize the panes, drag the border between them.
+    Select one of the viewports to make it the active viewport. The active viewport is marked with
+    a blue frame. Use the world axis helper to change the point of view for each viewport
+    independently. You can \l {Toggling the camera mode}{toggle the camera mode} between the
+    perspective and orthographic modes independently for each viewport.
+    \l {Navigating in the 3D scene}{Navigate} each split by panning, rotating, and zooming.
+    To resize the viewports, drag the border between them.
 
     \image {studio-3d-split-view.webp} {Split view in the 3D view.}