I have some code that draws trees using '|' and '-' characters to link nodes in the tree. For example:
8 8---| | 7 8---| | | 6 | 6---| | 5 8---| | 4 | 4---| | | 3 4---| | 2 2---| 1
I have a number of problems when I display the tree in a workspace (or debugger for that matter).
1) I need a fixed font so that symbols are properly aligned. This problem can be seen in the above figure but the effect is worse in Squeak. 2) I also need to add some additional information to my trees. The addition information is text ('|' and '-' characters linking nodes in the tree) and needs to be in color (Red) in order avoid making the figure too confusing. Thus I need to display attributed characters. Workspaces can handle this but I need for the 'printOn:' method to handle them as well. 3) I would like to add my own special characters to use instead of '|' and '-' so that there are no gaps between these special characters when used in my tree drawings. I know how the code works to draw the return and assignment arrows but I do not know if I need to use special fonts so that there are no forced gaps between characters and lines of text and if so which ones.
Is it possible for me to do these things and have my tree printed accordingly when my tree is displayed in a workspace (or debugger) resulting from a 'printOn: aStream' message? I know that the stream I get when the printOn: is invoked is a LimitedWriteStream. but not much more.
If it is not possible to do these things then I will settle for displaying it in a Text Pane. I still need to know which font to use though.
The code is part of my implementation of the Spine Tree Decomposition data structure which I will release to www.squeaksource.com when it is completed.
Any help most appreciated.
Ralph Boland
On Sat, 20 Jun 2009 15:55:41 +0200, Ralph Boland wrote:
I have some code that draws trees using '|' and '-' characters to link nodes in the tree. For example:
...
I have a number of problems when I display the tree in a workspace (or debugger for that matter).
- I need a fixed font so that symbols are properly aligned. This problem can be seen in the above figure but the effect is
worse in Squeak. 2) I also need to add some additional information to my trees. The addition information is text ('|' and '-' characters linking nodes in the tree) and needs to be in color (Red) in order avoid making the figure too confusing. Thus I need to display attributed characters.
As an example you can look how source methods are pretty printed with colors and tabs & breaks, see senders of
#withStyleFor:do: #withColor:emphasis:do:
Workspaces can handle this but I need for the 'printOn:' method to handle them as well. 3) I would like to add my own special characters to use instead of '|' and '-' so that there are no gaps between these special characters when used in my tree drawings. I know how the code works to draw the return and assignment arrows but I do not know if I need to use special fonts so that there are no forced gaps between characters and lines of text and if so which ones.
Is it possible for me to do these things and have my tree printed accordingly when my tree is displayed in a workspace (or debugger) resulting from a 'printOn: aStream' message?
Looks complicated, why can't you do (myObject myPrintTree) ? I mean instead of hacking system-level debugger or support-level workspace ?
I know that the stream I get when the printOn: is invoked is a LimitedWriteStream. but not much more.
If it is not possible to do these things then I will settle for displaying it in a Text Pane. I still need to know which font to use though.
Depends on what .image you're using, try this: select text in a method and do alt-k, that should bring up the list of fonts which are available.
HTH.
/Klaus
The code is part of my implementation of the Spine Tree Decomposition data structure which I will release to www.squeaksource.com when it is completed.
Any help most appreciated.
Ralph Boland
squeak-dev@lists.squeakfoundation.org
-
Klaus D. Witzel -
Ralph Boland