On Sonntag, 25. Februar 2018 21:35:41 CET maitai wrote:
> Just what I was looking for. I already live with using qt private stuff
>
Though if you want to check for only fully transparent pixels, and not just
some, it might be faster to do just do a memory compare against null. That
should be rea
Wow! Nice idea. Probably a bit faster than to compare with a known fully
transparent image.
Le 25-02-2018 21:41, Xavier Bigand a écrit :
> I think that I forgot to tell that it can be faster to do a pseudo random
> search than a pure straight forward brut-force lookup in the alpha channel
> buf
I think that I forgot to tell that it can be faster to do a pseudo random
search than a pure straight forward brut-force lookup in the alpha channel
buffer.
Depending on type of pictures you will analyse, it might be faster to have
an algorithm that do something like the quick search algorithm.
For
Just what I was looking for. I already live with using qt private stuff
:)
Many thanks.
Le 25-02-2018 20:55, Allan Sandfeld Jensen a écrit :
On Sonntag, 25. Februar 2018 20:23:32 CET maitai wrote:
Hello,
Seems quite basic, but I need a **fast** way to know if a QImage is
just
full transpar
A complete scan will always be relatively slow, if you can you should
consider to do a cache or something similar.
Depending of your constraints the cache should be created while
packaging/building your application or when the user will request the info
the first time.
The cacheKey() won't work in
On Sonntag, 25. Februar 2018 20:23:32 CET maitai wrote:
> Hello,
> Seems quite basic, but I need a **fast** way to know if a QImage is just
> full transparent. I know the size in advance (256x256). If it were a
> QPixmap I would use cacheKey() and compare with the cacheKey of a full
> transparent i
Hello,
Seems quite basic, but I need a **fast** way to know if a QImage is just
full transparent. I know the size in advance (256x256). If it were a
QPixmap I would use cacheKey() and compare with the cacheKey of a full
transparent image. For a QImage I can compare it with a preset
transparent
