Re: What are the differences between Picture, StdPicture and IPicture?

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> I will use (I'm testing) the GetPictureFromFile function for displaying png
> files. VB does'nt support this type and I don't use this picture as bmp or
> jpeg. Because this files have transparent field, some of them 32 bit icon
> pictures (what is it, alpha channel??, I'm very ignorant about graphic
> topics (to be more exact every topic)).

What you're referring to here is a 32-bit image with 4 channels; red, green, blue and alpha. The colour is made up of a
combination of red, green and blue and by combining various amounts of these primaries other colours can be created.
The Alpha channel then defines how transparent/opaque each pixel should be rendered, so any pixel with an alpha value of
0 will be completely transparent regardless of it's colour, where as pixels with an alpha value of 128 will be blended
50/50 with whatever background they're displayed on. By defining per-pixel alpha, icons can achieve effects such as
smooth edges and drop-shadows which properly blend over the background.
Hope this helps,

Mike


- Microsoft Visual Basic MVP -
E-Mail: EDais@xxxxxxxx
WWW: Http://EDais.mvps.org/


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