[Bf-docboard-svn] bf-manual: [8868] trunk/blender_docs/manual/modeling/meshes/editing/mesh/knife_project.rst: Clean up Knife Project documentation

[Aaron Carlisle]

Revision: 8868
          https://developer.blender.org/rBM8868
Author:   Blendify
Date:     2022-01-25 19:07:58 +0100 (Tue, 25 Jan 2022)
Log Message:
-----------
Clean up Knife Project documentation

The knife project documentation had not been updated to reflect the August/September 2021 updates that allow multi-object cutting.

In addition, the description of how to use the tool was not clear, as evidenced by several forum posts, YouTube videos, and questions on blender.chat's support channel about the tool.

This diff tries to make the usage of the tool clearer while showing how multiple cutters and objects are used.

Differential Revision: https://developer.blender.org/D13469

Modified Paths:
--------------
    trunk/blender_docs/manual/modeling/meshes/editing/mesh/knife_project.rst

Modified: trunk/blender_docs/manual/modeling/meshes/editing/mesh/knife_project.rst
===================================================================
--- trunk/blender_docs/manual/modeling/meshes/editing/mesh/knife_project.rst	2022-01-25 18:04:38 UTC (rev 8867)
+++ trunk/blender_docs/manual/modeling/meshes/editing/mesh/knife_project.rst	2022-01-25 18:07:58 UTC (rev 8868)
@@ -10,11 +10,16 @@
    :Menu:      :menuselection:`Mesh --> Knife Project`
 
 Knife projection is a non-interactive tool where you can use objects to cookie-cut into
-the mesh rather than hand drawing the line. The outline of selected objects
-that *are not* in Edit Mode are used to cut the mesh along the view axis of objects
-that are in Edit Mode. Afterwards the resulting geometry inside the cutters outline will be selected.
-Outlines can be a wireframe or boundary edges (i.e. the unconnected edges of a mesh).
+one or more meshes rather than hand drawing the line. The outline of selected objects
+that *are not* in Edit Mode are used to cut the meshes along the view axis of objects
+that *are* in Edit Mode. Afterwards the resulting geometry inside the cutters outline will be selected.
+Outlines can be a wireframe or boundary edges (i.e. the unconnected edges of a mesh), as well as 
+Curve objects.
 
+Keep in mind that Knife Project works from the current view's perspective.  For best results, make sure
+to rotate your view to exactly the position you require before using this tool.  Orthographic views such
+as Right, Front, and Top are commonly used for more predictable results.
+
 .. note::
 
    The primitives, being manifold objects, do not have wireframe or boundary edges.
@@ -22,10 +27,13 @@
    :ref:`Select Non-Manifold <bpy.ops.mesh.select_non_manifold>`
    (Wire, Boundaries) will highlight the cutting edges of mesh objects.
 
-To use Knife Project, first in *Object Mode* select the object to be cut,
-then in *Edit Mode*, select the cutting object (:kbd:`Ctrl-LMB`),
-and choose :menuselection:`Mesh --> Knife Project`.
+   In general, for flat shapes, you will usually want to select "Faces Only" from the delete menu to leave 
+   behind only edges.
 
+To use Knife Project, first in *Object Mode* select the objects to be cut,
+then switch to *Edit Mode* and select the cutting objects in the Outliner (:kbd:`Ctrl-LMB`),
+and finally choose :menuselection:`Mesh --> Knife Project`.
+
 .. hint::
 
    :doc:`3D Viewport Alignment </editors/3dview/navigate/align>` to adjust the projection axis.
@@ -35,7 +43,7 @@
 =======
 
 Cut Through
-   Projects the cut through the entire mesh.
+   Projects the cut through the entire mesh, including back faces not currently visible.
 
 
 Examples