Modifiers and Mouse Buttons

Modifiers are the status of special keyboard shift-like keys. The state of these keys can be read as up or down, and don't generate any characters by themselves. These keys are for things like SHIFT, CTRL, and ALT. They are returned as bit values OR'd together in various events. Not all of these modifiers may be implemented. The GrGetScreenInfo function returns the modifiers that are implemented. The following modifiers are defined:

	GR_MODIFIER_SHIFT	shift key is down
	GR_MODIFIER_CTRL	ctrl key is down
	GR_MODIFIER_META	meta (or ALT) key is down
	GR_MODIFIER_ANY		any of the modifiers is down

The mouse button state are returned as bit values OR'd together in various events. Not all of these buttons may be implemented. The GrGetScreenInfo function returns the buttons that are implemented. The following mouse buttons are defined:

	GR_BUTTON_1		button 1 is down (left)
	GR_BUTTON_2		button 2 is down (middle)
	GR_BUTTON_3		button 3 is down (right)
	GR_BUTTON_ANY		any of the buttons is down