How to make new tools
The best is to derive from existing tools, and redefine only what you don't like. The tools often function within a group of tools. They share a common way of using mouse buttons, and it is oke to push a tool unto the stack, and returning to the parent tool after stopping itself. Like tools based on a2dStTool use all as controller a2dStToolContr.
Changing State
A tool is used to manipulate what is in a drawing. User input combined with selected objects and mouse hit objects, brings a tool from one state into another. Down here some examples of what can bring a tool into a different state.
||<rowstyle="background-color: #FFFFE0;">
mouse event ||key state || object hit ||object selected||
Ctrl Down |
true |
1 |
|
LeftDown + drag |
Ctrl Down |
true |
1 |
LeftDown + drag |
Shift Down |
true |
1 |
LeftDown + drag |
Alt Down |
true |
1 |
RightDown + drag |
Ctrl Down |
true |
1 |
Alt Down |
true |
1 |
Tool state
Zoom Tool
