On my setup Py2.7/Qt4.8/Win7 Leo has noticeable performance issues in the 
outline pane when holding down the Up/Down arrows. I've analyzed the 
behavior and from past conversations I've determined the slowdown/lag is 
due to syntax highlighting in node bodies. The more code in the body, the 
worse the slowdown. This is because Leo tries to redraw a node as it is 
selected in the outline. The problem with this is only seen when you hold 
down the Up/Down arrows, because the user is moving over a large number of 
nodes quickly Leo is trying to syntax highlight them even if you're not 
stopping on that node. 

The fix appears simple: while the Up/Down arrow is being held down empty 
the body pane and do not redraw or try to do any syntax highlighting until 
the Up/Down arrow is release. There is no downside to this, for several 
reasons: 

   - body content does not stay in the body pane long enough for it to be 
   intelligible.
   - sometimes body content gets locked to the content seen when user first 
   pressed and held the Up/Down arrow.
   - User is likely focusing on outline pane anyway

For this reason I propose the described enhancement. It has the potential 
to make Leo much snappier.

-- 
You received this message because you are subscribed to the Google Groups 
"leo-editor" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/leo-editor.
For more options, visit https://groups.google.com/d/optout.

Reply via email to