Tool icons could change with tool mode

[humdingerb]

There are tool that present several modes. The tool icon could reflect the currently set mode, so you wouldn't need to have the "Tool setup" window open to know in what mode the tool will be used.

• Straight line - normal and adjustable width (icon could get a wider line)
• Rectangle - outline, filled, rotation (obvious icons, rotation gets additional rotational arrows)
• Ellipse - outline, filled (similar to Rectangle, rotation feature currently missing)
• Airbush - spray and airbrush (spray gets dotted lines instead of spray-cone)
• Fill - normal fill and gradient (obvious icons, "flood fill" could add some overlayed symbol)
• Eraser - background and transparency (transparency adds some alpha checkers somehow)
• Selection - several modes (obvious icons, all should include some form of ant-line)

Much depends how good our icon skills are of course... )