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How to make transparent or semi-transparent in my app
| Wed, 2004-10-06 19:33 | |
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I found implement in class RWindow (w32std.h) IMPORT_C void HandleTransparencyUpdate(); IMPORT_C TInt SetTransparencyFactor(const TRgb& aTransparencyFactor); IMPORT_C TInt SetTransparencyBitmap(const CFbsBitmap& aTransparencyBitmap); IMPORT_C void SetNonTransparent(); but i don't know how to use.. thankyou for reply. Visit my site at http://www.symbianplus.com |
Forum posts: 7
Class TGopBitBltAlphaBitmap
TGopBitBltAlphaBitmap
Support
Supported from 7.0
Description
An accelerated graphics operation that copies a rectangular region of one bitmap into another using alpha blending values provided in a third bitmap.
The way alpha blending works is as follows: if the alpha value is the maximum, the source pixel is opaque, in other words, the full colour of the pixel is written to the destination. If the alpha value is zero, the source pixel is fully transparent, and the destination is left unaltered. Values in-between cause blending with the following formula:
Destination = Source*Alpha/max_Alpha + Destination*(max_Alpha-Alpha)/max_Alpha
Colour alpha bitmaps specify red, green and blue alpha values for each pixel, greyscale bitmaps specify a single alpha value for each pixel. The maximum alpha value depends on the bitmap's display mode. For example, 255 is the maximum for an EGray256 or EColor16M bitmap. The maximum is less for bitmaps which use fewer bits per colour component.