10 Rendering
parameter
(dc-for-text-size) → (or/c #f (is-a?/c dc<%>))
(dc-for-text-size dc) → void? dc : (or/c #f (is-a?/c dc<%>))
A parameter that is used to determine the bounding box of picts
created with text.
The drawing context installed in this parameter need not be the same as the ultimate drawing context, but it should measure text in the same way. Under normal circumstances, font metrics are the same for all drawing contexts, so the default value of dc-for-text-size is a bitmap-dc% that draws to a 1-by-1 bitmap.
Draws pict to dc, with its top-left corner at offset
(x, y).
procedure
(pict->bitmap pict) → (is-a?/c bitmap%)
pict : pict?
Returns a bitmap% with an alpha channel, no larger than pict, with pict drawn on it in the top-left corner (0, 0).
Generates a pict-drawer procedure for multiple renderings of
pict. Using the generated procedure can be faster than
repeated calls to draw-pict.
procedure
(show-pict pict [ w h] #:frame-x frame-x #:frame-y frame-y #:frame-style frame-style) → void? pict : pict? w : (or/c #f exact-nonnegative-integer?) = #f h : (or/c #f exact-nonnegative-integer?) = #f frame-x : (or/c (integer-in -10000 10000) #f) frame-y : (or/c (integer-in -10000 10000) #f)
frame-style :
(listof (or/c 'no-resize-border 'no-caption 'no-system-menu 'hide-menu-bar 'toolbar-button 'float 'metal))
Opens a frame that displays pict. The frame adds one method,
set-pict, which takes a pict to display. The optional
w and h arguments specify a minimum size for the
frame’s drawing area, and the frame-x, frame-y,
and frame-style keyword arguments behave in the same manner as x,
y, and style arguments for the frame%.
parameter
(current-expected-text-scale scales) → void? scales : (list real? real?)
A parameter used to refine text measurements to better match an
expected scaling of the image. The scale/improve-new-text
form sets this parameter while also scaling the resulting pict.