Add link from Rendering to 2D and 3D rendering sections

tutorials/2d/index.rst

@@ -10,6 +10,8 @@
    canvas_layers
    2d_transforms
 
+.. _doc_2d_rendering:
+
 Rendering
 ---------
 

tutorials/3d/index.rst

@@ -12,6 +12,8 @@
    procedural_geometry/index
    3d_text
 
+.. _doc_3d_rendering:
+
 Rendering
 ---------
 

tutorials/rendering/index.rst

@@ -3,6 +3,11 @@
 Rendering
 =========
 
+.. seealso::
+
+   Most rendering topics are covered in :ref:`2D rendering <doc_2d_rendering>`
+   and :ref:`3D rendering <doc_3d_rendering>`.
+
 .. toctree::
    :maxdepth: 1
    :name: toc-learn-features-rendering