🚀 go-pugleaf

In article <1993Jan7.211926.11912@physics.ucla.edu> mmccarri@physics.ucla.edu writes:

>I could rotate a bitmap pixel by pixel, but it seems like a
>lot of work given the various color formats.  Is there an
>easier (and faster) way?
>

Write your application under Win32s and use the "World Transforms" that
Win32 gives you.  Rotation is then just as easy as translation and
scaling now are.

>Speaking of bitmaps, I am drawing a large, multi-color bitmap
>(a frequeny-time spectrogram) using the Rectangle() function
>to fill in each df dt block.  This also seems like too much 
>work since I have to create a pen and a brush with the desired
>color, select these objects, draw the rectangle, and then delete
>both objects.  This is repeated 100,000 times or so and is very
>slow.  I experimented with the SetPixel() function instead, but
>it is even slower!  Also, SetPixel() will not dither the color
>if I am running on a paletteless display.  Any suggestions?
>

1.  Use PatBlt rather than Rectangle - it's a lot faster.
2.  Create all the brushes you need at the start, do the drawing,
    then delete all the brushes at the end.
3.  SetPixel will *never* create a dithered colour, whether or not
    the display is palette-based.

>Thanks,
>-Mike-
>-- 
>Dr. Michael McCarrick                   UCLA Department of Physics
>Plasma Physics Lab                              405 Hilgard Avenue
>mmccarri@physics.ucla.edu                    Los Angeles, CA 90024
>

Chris
-- 
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| Chris Marriott                           | chris@chrism.demon.co.uk    |
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