How to set transparency

Hi again!
I've read the documentation but I haven't found how I can set the transparency of my sprites. I have a sprite sheet with the blue background, but the background still appears. How can I set this?
Thanks.

selim

Mmm this can't be done through gameQuery, you need to do this with an image editor. This also means that you'll need to use an image format that supports transparency: PNG or GIF.

You have to keep in mind that GIF file don't support 'partial' transparency but it works fine with all versions of IE whereas PNG suport full alpha channel but display weirdly on older version of IE.

If you tell me what image editor you use, I may be able to help...

I use GIMP and I've used PNG images once for a game with SDL.

selim

In GIMP you can select all the pixels of a given color (look at this documentation). Then you can simply clear the content you selected this way. If this doesn't work it means that your layer doesn't contain an alpha channel and you have to add one before you clear the selection.

Thank for you your reply. It works, the image is transparent, but when you select by color it's not precise enough, so I can still see a few background color close to the picture. Do I have to remove it manually ?
:((

selim

Well you can try the magic wand and play with the threshold but it won't prevent some manual correction.

Thank you Selim, you're awesome!

Howdy, Stranger!

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