|
Syntax |
GRAPHIC STRETCH hbmpSource???, id&,
(x1!, y1!)-(x2!, y2!) TO (x3!, y3!)-(x4!,y4!)
[, mix&, stretch&] |
|
Remarks |
You can copy a complete bitmap, or a portion of
it, to the selected graphic target, while resizing it to a larger or smaller
size. The expression hbmpSource???
specifies the handle of the source
bitmap or window.
The expression id is reserved for future compatibility, and must always
be set to zero. The
destination of the copy operation is the target specified by GRAPHIC
ATTACH. The
bitmap is automatically resized to fit the destination parameters. You
must use care that your parameters are valid for the specified bitmaps,
or results of the operation are undefined.
If the mix&
parameter is included, it is one of the values in the following table.
If not
included, a default of %mix_CopySrc is presumed. There
are 8 mix modes available to use for mixing drawing colors with the colors
which already exist at the at the drawing location. The
mix mode equates are predefined in PowerBASIC.
The 8 mix modes are:
|
%MIX_NOTMERGESRC |
Pixel is the inverse of
the MergeSrc color. |
|
%MIX_NOTCOPYSRC |
Pixel is the inverse of
the source color. |
|
%MIX_MASKSRCNOT |
Pixel is a combination
of the colors common to both the source and the inverse of the pixel. |
|
%MIX_XORSRC |
Pixel is a combination
of the colors in the source and the pixel, but not in both. |
|
%MIX_MASKSRC |
Pixel is a combination
of the colors common to both the source and the pixel. |
|
%MIX_MERGENOTSRC |
Pixel is a combination
of the pixel color and the and the inverse of the source color. |
|
%MIX_COPYSRC |
Pixel is the source color
(Default Mode). |
|
%MIX_MERGESRC |
Pixel is a combination
of the source color and the pixel color. |
If the stretch& parameter
is included, it is one of the values in the following table. If
not included, or it is the value zero (0), the stretch mode is unchanged.
An appropriate
choice of stretch mode can substantially enhance the quality of bitmaps
which are changed in size. The stretch mode equates are predefined in
PowerBASIC.
The 4 stretch modes are:
|
%BLACKONWHITE |
This is the default Windows
stretch mode, and is most appropriate for monochrome bitmaps, or those
with blocks of color. Performs a boolean OR of eliminated and existing
pixels. It preserves black pixels at the expense of white pixels. |
|
%WHITEONBLACK |
Performs a boolean OR of
eliminated and existing pixels. It
preserves white pixels at the expense of black pixels. |
|
%COLORONCOLOR |
Deletes eliminated lines
of pixels without trying to preserve their information. |
|
%HALFTONE |
This provides the highest
quality for complex color bitmaps. The
average color of the destination pixel block is kept approximately the
same as the source pixel block. |
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