Hi,

robbie chen <[EMAIL PROTECTED]> writes:

> Hi all:
>       I want to blit an surface which contain some pixel(its
> alphavalue = 0) ,but on the destination surface those pixel appear
> to be black.Any way to make those pixel to be transparent on
> destination surface? Fore Example:
>       
>      1. I create an 200*200 , pixelformat=argb source surface,then I
>         set foreground color to red,and draw an triangle at
>         (0,0),(200,100),(0,200) on this surface.
>      2. set destination surface blittingflag DSBLIT_BLEND_ALPHACHANNEL
>      3. blit source surface to destination surface 
>
> As a result,an black rectangle with an red trangle in it on destination 
> surface .How do I get rid of those boring black pixel?

did you clear the ARGB surface to transparency before you draw the red
triangle on it? Like this:  surface->Clear (surface, 0, 0, 0, 0); 


Salut, Sven


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