Graphics ports has two drawing modes:
Compatible with LispWorks 6.0 and earlier versions
Introduced in LispWorks 6.1, allowing high quality drawing
The main visible effect is that with
drawing-mode
:quality
, all drawings are transformed properly.
With
drawing-mode
:compatible
, strings and images are not scaled or rotated at all, and ellipses are not rotated correctly. Other shapes are transformed "at the front", that is they are drawn as if the drawing function was called with transformed coordinates. The target of
copy-pixels
is also transformed "at the front", that is the rectangle can be translated, but not scaled or rotated.
With
drawing-mode
:quality
, all drawings are fully transformed correctly. Shapes are transformed "at the back", that is they are drawn and then the result of the drawing is transformed. Note that
clear-rectangle
and
pixblt
are not drawing functions in this sense, and do not take transforms into account.
Another difference is that
drawing-mode
:quality
supports anti-aliasing on Windows, and on GTK+ it adds control over anti-aliasing. See
shape-mode
and
text-mode
in the page for
graphics-state
in the
LispWorks CAPI Reference Manual
.
With
drawing-mode
:quality
the
operation
value in the
graphics-state
is not supported and is ignored. This is because operations do not combine sensibly with anti-aliasing and colors with alpha components. Instead, there is now
compositing-mode
. See the page for
graphics-state
in the
LispWorks CAPI Reference Manual
.
On Microsoft Windows with
drawing-mode
:quality
only Truetype fonts are supported.
The
drawing-mode
of all graphics ports is
:quality
by default, except when a graphics port is made in association with another graphics ports (for exanple, by
create-pixmap-port
), in which case the
drawing-mode
is inherited from the "parent" graphics port.
All the interfaces that create graphics ports, or modify a graphics port to draw to another place, take keyword argument
:drawing-mode
. Its value
drawing--mode
can be
:quality
,
:compatible
, or
nil
which is interpreted as use the default (either inherited or the global default
:quality
). These interfaces are listed in Creating instances.
These examples in the
examples/capi/graphics/
directory demonstrate features that are available only with
drawing-mode
:quality
:
Using compositing-mode , transforming an image.
CAPI User Guide (Unix version) - 30 Aug 2011