Alvechurch Data - Pixels, Points, and Twips
There are three ways in which VB masure the size of things on the
screen - pixels, points, and twips. All three have their uses but you
must always be sure that you know which units you are using.
The three are:
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Pixel
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This is a "picture element" and is the smallest area of screen that Visual Basic
can control. You can set or test the colour of a pixel but you can't do anything
with colours within a pixel. The Control Panel measures the screen sizes in pixels;
typical sizes are 640 x 480 or 1280 x 1024 pixels.
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Point
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The point is a traditional printer's measure of font size on paper. One point
was 1/72nd of an inch. The pica is 12 points or 1/6th of an inch.
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Twip
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A device-independent measurement defined as 1/20th of a point. This equates to
1/1440th of an inch or about 1/567th of a centimetre. You can use the TwipsPerPixelX
and TwipsPerPixelY to convert between twips and pixels.
There is also a logical twip, this is the length on screen that will be one twip
long when printed.
Those of us who believe that the IT industry takes itself too seriously mourn the loss of
the "mickey". This was defined in the Windows SDK as the distance that the mouse must
be moved before Windows will recognise that it has moved. If the mouse moves more than one
mickey between button press and release then that's a drag-and-drop, not a click.