The protocol class that corresponds to the output state for some kind of sheet. There is no single advertised standard medium class. If you want to create a new class that behaves like a medium, it should be a subclass of medium. All instantiable subclasses of medium must obey the medium protocol. [annotate]

[annotate]

Returns true if object is a medium, otherwise returns false. [annotate]

[annotate]

The basic class on which all CLIM mediums are built, a subclass of medium. This class is an abstract class, intended only to be subclassed, not instantiated. [annotate]

The following generic functions comprise the basic medium protocol. All mediums must implement methods for these generic functions. Often, a sheet class that supports the output protocol will implement a "trampoline" method that passes the operation on to sheet-medium of the sheet. [annotate]

[annotate]

Returns (and, with setf, sets) the current foreground ink for the medium medium. This is described in detail in Chapter 10. [annotate]

[annotate]

Returns (and, with setf, sets) the current background ink for the medium medium. This is described in detail in Chapter 10. [annotate]

[annotate]

Returns (and, with setf, sets) the current drawing ink for the medium medium. This is described in detail in Chapter 10. [annotate]

[annotate]

Returns (and, with setf, sets) the "user" transformation that converts the coordinates presented to the drawing functions by the programmer to the medium medium's coordinate system. By default, it is the identity transformation. This is described in detail in Chapter 10. [annotate]

[annotate]

Returns (and, with setf, sets) the clipping region that encloses all output performed on the medium medium. It is returned and set in user coordinates. That is, to convert the user clipping region to medium coordinates, it must be transformed by the value of medium-transformation. For example, the values returned by [annotate]

(let (cr1 cr2)
  ;; Ensure that the sheet's clipping region and transformation will be reset:
  (with-drawing-options (sheet :transformation +identity-transformation+
                               :clipping-region +everywhere+)
    (setf (medium-clipping-region sheet) (make-rectangle* 0 0 10 10))
    (setf (medium-transformation sheet) (clim:make-scaling-transformation 2 2))
    (setf cr1 (medium-clipping-region sheet))
    (setf (medium-clipping-region sheet) (make-rectangle* 0 0 10 10))
    (setf (medium-transformation sheet) +identity-transformation+)
    (setf cr2 (medium-clipping-region sheet))
    (values cr1 cr2)))

are two rectangles. The first one has edges of (0,0,5,5), while the second one has edges of (0,0,20,20). [annotate]

By default, the user clipping region is the value of +everywhere+. [annotate]

Major issue: What exactly are "user coordinates"? We need to define all of the coordinate systems in one place: device, window, stream, etc. --- SWM [annotate]

[annotate]

Returns (and, with setf, sets) the current line style for the medium medium. This is described in detail in Chapter 10 and Section 10.3. [annotate]

[annotate]

Returns (and, with setf, sets) the current text style for the medium medium of any textual output that may be displayed on the window. This is described in detail in Chapter 10. [annotate]

[annotate]

Returns (and, with setf, sets) the default text style for output on the medium medium. This is described in detail in Chapter 10. [annotate]

[annotate]

Returns the actual text style used in rendering text on the medium medium. It returns the result of [annotate]

 
(merge-text-styles (medium-text-style medium)
                   (medium-default-text-style medium))

Thus, those components of the current text style that are not nil will replace the defaults from medium's default text style. Unlike the preceding text style function, medium-merged-text-style is read-only. [annotate]

[annotate]

This class is mixed in to any sheet that provides the standard output protocol, such as repainting and graphics. [annotate]

[annotate]

This class is mixed in to any sheet that provides none of the output protocol. [annotate]

[annotate]

This class is used for any sheet that has either a permanent or a temporary medium. [annotate]

[annotate]

This class is mixed in to any sheet that always has a medium associated with it. It is a subclass of sheet-with-medium-mixin. [annotate]

[annotate]

This class is mixed in to any sheet that may have a medium associated with it, but does not necessarily have a medium at any given instant. It is a subclass of sheet-with-medium-mixin. [annotate]

[annotate]

Within the body, the variable medium is bound to the sheet's medium. If the sheet does not have a medium permanently allocated, one will be allocated and associated with the sheet for the duration of the body (by calling engraft-medium), and then degrafted from the sheet and deallocated when the body has been exited. The values of the last form of the body are returned as the values of with-sheet-medium. [annotate]

This macro will signal a runtime error if sheet is not a subclass of sheet-with-medium-mixin. [annotate]

The medium argument is not evaluated, and must be a symbol that is bound to a medium. body may have zero or more declarations as its first forms. [annotate]

[annotate]

with-sheet-medium-bound is used to associate the specific medium medium with the sheet sheet for the duration of the body body. Typically, a single medium will be allocated an passed to several different sheets that can use the same medium. [annotate]

If the sheet already has a medium allocated to it, the new medium will not be grafted to the sheet, and with-sheet-medium-bound will simple evaluate the body. If the value of medium is nil, with-sheet-medium-bound is exactly equivalent to with-sheet-medium. The values of the last form of the body are returned as the values of with-sheet-medium-bound. [annotate]

This macro will signal a runtime error if sheet is not a subclass of sheet-with-medium-mixin. [annotate]

body may have zero or more declarations as its first forms. [annotate]

[annotate]

Returns the medium associated with the sheet sheet. If sheet does not have a medium allocated to it, sheet-medium returns nil. [annotate]

This function will signal an error if sheet is not a subclass of sheet-with-medium-mixin. [annotate]

[annotate]

Returns the sheet associated with the medium medium. If medium is not grafted to a sheet, medium-sheet returns nil. [annotate]

[annotate]

Returns an implementation-dependent object that corresponds to the actual host window that will be drawn on when the medium medium is drawn on. If medium is not grafted to a sheet or the medium's sheet is not currently mirrored on a display server, medium-drawable returns nil. [annotate]

Programmers can use this function to get a host window system object that can be manipulated using the functions of the host window system. This might be done in order to explicitly trade of performance against portability. [annotate]

[annotate]

If medium is both grafted to a sheet and the sheet is currently mirrored on a display server, this returns the port with which medium is associated. Otherwise it returns nil. [annotate]

[annotate]