CrystGLFW::Window::Cursor

A CrystGLFW::Window::Cursor (or Cursor, for the purposes of this guide) represents the system cursor with respect to a given Window. Objects of type Cursor are always associated with a Window and can only be created indirectly through a Window.

cursor

You can create a Cursor by using the cursor method:

window = Window.new
cursor = window.cursor # => CrystGLFW::Window::Cursor

Internally, if window does not yet have a cursor assigned to it, then one will be created and returned from the cursor method. If a Cursor has already been created for this window, then that Cursor will be returned.

If you wish to create a new Cursor for window with a given Cursor::Shape, you can pass it to the cursor method:

window = Window.new
cursor = window.cursor(Window::Cursor::Shape::Arrow) # creates a cursor with the standard arrow shape

cursor = window.cursor(Window::Cursor::Shape::Crosshair) # creates a cursor with the crosshair shape

cursor = window.cursor # returns the previously created crosshair cursor.

The available shapes are:

• Arrow
• IBeam
• Crosshair
• Hand
• HResize
• VResize

You can also create a Cursor with a custom appearance:

window = Window.new
image = Window::Image.new(32, 32, pixels)
cursor = window.cursor(image, 0, 0) # creates a cursor that looks like *image*

When creating a custom cursor, the cursor method accepts the following arguments:

• image, the Image that the cursor should look like.
• x, the x-coordinate of the cursor's hotspot.
• y, the y-coordinate of the cursor's hotspot.

The cursor method must be called from within a run block definition.

remove_cursor

You can remove a window's cursor without assigning a new cursor using the remove_cursor method:

window = Window.new
cursor = window.cursor(Window::Cursor::Shape::Hand)

window.remove_cursor # removes the hand cursor, now the window has no cursor.

remove_cursor must be called from within a run block definition.