Check-in [66f5d2177b]

	"171":{"url":"./tip/171.md","created":"05-Mar-2004","post-history":"","state":"Final","tcl-version":"8.6","vote":"Done","type":"Project","title":"# TIP 171: Change Default <MouseWheel> Bindings Behavior","author":["Jeff Hobbs <[email protected]>","Keith Vetter <[email protected]>"],"is-jest":false},
	"170":{"url":"./tip/170.md","created":"30-Jan-2004","post-history":"","state":"Draft","implementation-url":"http://nac.sf.net/","tcl-version":"8.7","vote":"Pending","type":"Project","title":"# TIP 170: Better Support for Nested Lists","author":["Sergey Babkin <[email protected]>","Don Porter <[email protected]>","Donal K. Fellows <[email protected]>"],"is-jest":false},
	"169":{"url":"./tip/169.md","tk-ticket":"994629","created":"28-Jan-2004","post-history":"","state":"Final","tcl-version":"8.5","vote":"Done","type":"Project","title":"# TIP 169: Add Peer Text Widgets","author":["Brian Griffin <[email protected]>","Vince Darley <[email protected]>"],"is-jest":false},
	"168":{"url":"./tip/168.md","tk-ticket":"886240","created":"25-Jan-2004","post-history":"","state":"Final","vote":"Done","tcl-version":"8.5","type":"Project","title":"# TIP 168: Cubic Bezier Curves on the Canvas","author":["Lars Hellström <[email protected]>"],"is-jest":false},
	"167":{"url":"./tip/167.md","tk-ticket":"845248ffffffffffffff","created":"19-Nov-2003","post-history":"","state":"Draft","tcl-version":"8.7","vote":"Pending","type":"Project","title":"# TIP 167: Add a New Option for Context Help for Windows","author":["Ramon Ribó <[email protected]>"],"is-jest":false},
	"166":{"url":"./tip/166.md","keywords":"Tk,image get,image put","created":"19-Nov-2003","post-history":"","state":"Final","tk-branch":"tip-166","tcl-version":"8.7","vote":"Done","type":"Project","title":"# TIP 166: Reading and Writing the Photo Image Alpha Channel","author":["Donal K. Fellows <[email protected]>","Simon Bachmann <[email protected]>"],"is-jest":false},
	"165":{"url":"./tip/165.md","tk-ticket":"1008975","keywords":"Tk,substitution","created":"17-Nov-2003","post-history":"","state":"Final","tcl-version":"8.5","vote":"Done","type":"Project","title":"# TIP 165: A User-Data Field for Virtual Events","author":["Donal K. Fellows <[email protected]>"],"is-jest":false},
	"164":{"url":"./tip/164.md","keywords":"Tk,canvas","created":"17-Nov-2003","post-history":"","state":"Draft","tk-branch":"tip-164","tcl-version":"8.7","vote":"Pending","type":"Project","title":"# TIP 164: Add Rotate Subcommand to the Canvas Widget","author":["Arjen Markus <[email protected]>","Dimitrios Zachariadis <[email protected]>","Donal K. Fellows <[email protected]>"],"is-jest":false},
	"163":{"url":"./tip/163.md","tcl-ticket":"745851","created":"14-Nov-2003","post-history":"","state":"Final","vote":"Done","tcl-version":"8.5","type":"Project","title":"# TIP 163: A [dict merge] Subcommand","author":["Joe English <[email protected]>"],"is-jest":false},
	"162":{"url":"./tip/162.md","created":"23-Oct-2003","post-history":"","state":"Final","tcl-branch":"rmax-ipv6-branch","tcl-version":"8.6","vote":"Done","type":"Project","title":"# TIP 162: IPv6 Sockets for Tcl","author":["Rafael Martínez Torres <[email protected]>","Donal K. Fellows <[email protected]>","Reinhard Max <[email protected]>"],"is-jest":false},
	"161":{"url":"./tip/161.md","created":"19-Oct-2003","post-history":"","state":"Final","tk-branch":"tip-161","tcl-version":"8.7","vote":"Done","type":"Project","title":"# TIP 161: Change Default for Menu's -tearoff Option to False","author":["Mark Roseman <[email protected]>","Francois Vogel <[email protected]>"],"is-jest":false},
	"160":{"url":"./tip/160.md","created":"17-Oct-2003","post-history":"","state":"Draft","vote":"Pending","tcl-version":"8.7","type":"Project","title":"# TIP 160: Improvements to Terminal and Serial Channel Handling","author":["Donal K. Fellows <[email protected]>"],"is-jest":false},
	"159":{"url":"./tip/159.md","tk-ticket":"815751","created":"01-Oct-2003","post-history":"","state":"Final","tcl-version":"8.5","vote":"Done","type":"Project","title":"# TIP 159: Extending Tk 'wm' Command to Support Coloured Icons","author":["Georgios Petasis <[email protected]>"],"is-jest":false},
	"158":{"url":"./tip/158.md","tk-ticket":"797404","created":"20-Sep-2003","post-history":"","state":"Final","tcl-version":"8.5","vote":"Done","type":"Project","title":"# TIP 158: Distinguish the two 'Enter' keys on Windows","discussions-to":"news:comp.lang.tcl","author":["Wolfgang Großbauer <[email protected]>","Kevin Kenny <[email protected]>"],"is-jest":false},
	"157":{"url":"./tip/157.md","obsoletes":"144","created":"20-Sep-2003","post-history":"","state":"Final","tcl-version":"8.5","vote":"Done","type":"Project","title":"# TIP 157: Argument Expansion with Leading {expand}","author":["Kevin B. Kenny <[email protected]>","Peter Spjuth <[email protected]>","Donal K. Fellows <[email protected]>","Don Porter <[email protected]>"],"is-jest":false},

	"4":{"url":"./tip/4.md","created":"26-Oct-2000","post-history":"","state":"Draft","vote":"Pending","type":"Informative","title":"# TIP 4: Tcl Release and Distribution Philosophy","discussions-to":"news:comp.lang.tcl","author":["Brent Welch <[email protected]>","Donal K. Fellows <[email protected]>","Larry W. Virden <[email protected]>","Larry W. Virden <[email protected]>"],"is-jest":false},
	"3":{"url":"./tip/3.md","created":"14-Sep-2000","post-history":"","state":"Accepted","vote":"Done","type":"Process","title":"# TIP 3: TIP Format","author":["Andreas Kupries <[email protected]>","Donal K. Fellows <[email protected]>"],"is-jest":false},
	"2":{"url":"./tip/2.md","created":"12-Sep-2000","post-history":"","state":"Draft","vote":"Pending","type":"Process","title":"# TIP 2: TIP Guidelines","author":["Andreas Kupries <[email protected]>","Donal K. Fellows <[email protected]>","Don Porter <[email protected]>","Mo DeJong <[email protected]>","Larry W. Virden <[email protected]>","Kevin Kenny <[email protected]>"],"is-jest":false},
	"1":{"url":"./tip/1.md","created":"14-Sep-2000","post-history":"","state":"Active","vote":"No voting","type":"Informational","title":"# TIP 1: TIP Index","author":["TIP Editor <[email protected]>"],"is-jest":false},
	"0":{"url":"./tip/0.md","created":"11-Dec-2000","post-history":"","state":"Final","vote":"Done","type":"Process","title":"# TIP 0: Tcl Core Team Basic Rules","author":["John Ousterhout <[email protected]>"],"is-jest":false},
	"@min": 0,
	"@max": 535
}, "@timestamp": 1552297554}

</tr>
<tr class='project projectdraft projectdraft87 project87'>
<td valign='top'><a href='./tip/164.md'>164</a></td>
<td valign='top'>Project</td>
<td valign='top'>8.7</td>
<td valign='top'>Draft</td>
<td valign='top'># TIP 164: Add Rotate Subcommand to the Canvas Widget</td>
<td valign='top'><a href='/tk/timeline?r=tip-164'>Link</a></td>
</tr>
<tr class='project projectfinal projectfinal85 project85'>
<td valign='top'><a href='./tip/163.md'>163</a></td>
<td valign='top'>Project</td>
<td valign='top'>8.5</td>
<td valign='top'>Final</td>
<td valign='top'># TIP 163: A [dict merge] Subcommand</td>

# TIP 164: Add Rotate Subcommand to the Canvas Widget
	Author:         Arjen Markus <[email protected]>
	Author:         Dimitrios Zachariadis <[email protected]>
	Author:         Donal K. Fellows <[email protected]>
	State:          Draft
	Type:           Project
	Vote:           Pending
	Created:        17-Nov-2003
	Post-History:   
	Keywords:       Tk,canvas
	Tcl-Version:    8.7
	Tk-Branch:      tip-164
-----

# Abstract

This TIP proposes to add a **rotate** subcommand to the **canvas** widget
to facilitate rotating items in very much the same way as is now
possible with scaling and moving.

## Canvas Item C API Alterations

[These are required for this TIP, but are not yet done.]

# Reference Implementation

See the `tip-164` branch.

# Future Work

Should we also consider the possibility of reflections in a line?

Should we also consider more general linear transformations \(to be specified via a 2x2 matrix\)?  What about full affine transformations \(i.e. with the translation components\)?