How to Make Pixels ( = fuzzy equal to certain RGB values) Transparent.

We need 3 attributes to make a new costume: Pixels, width and height. If you wish to reuse the dimensions of the current costume you can use the new "show picture" block that's left in the "Pixels" library.

Yes, (but) the changed SWITCH primitive could assume that the width and height are equal to the stage's width and height, if the MAP's result's (i.e. list's) length would prove to be equal to width of stage * height of stage, or am I wrong?

interesting idea...

I mean to say that it is not totally an outrageous idea, because the "show picture" block assumes something, too, as you described, it assumes the w*h of current costume, yes?

it could be so that if you pass a list into the SWITCH TO block it would try to distribute its contents into a bitmap of the same dimensions as the current one. That could actually work!

yessss big smile

I like it, great idea!

Just one question. You seem to prefer that the assumed width and height are those of current costume, but in my case the "output" sprite has no costume whatsoever, and thus it would be nicer to assume the stage's width and height providing that the MAP's result's (i.e. list's) length equals to the stage's w*h? Just asking.
EDIT: well, never mind, I could initialize my "output" sprite to have some initial costume. So, basically, it can be your way. Thanks.

yes, this way you can initialize your output sprite any way you like, and the feature would be more versatile, I think, letting you work with multiple different sprites.

@kinestheticlearning: I've just pushed an experimental commit to the Github repo implementing this idea: https://github.com/jmoenig/Snap/commit/6ff5dcd6bb8b1024897554b9a47800bb26347748 so far I like it!

Yay! I feel like a kid waiting to play with an exciting new toy.

Can I try it, using the development version of the Snap! online?

I don't think we've set up the dev stream yet. But you can download the repo and use it offline.

Just another silly question (about downloading repo), because I am not sure if this is it, I made a printscreen below. Is this it?

Screenshot

Yes, "Download ZIP" is fine. (There are other ways too, which is why the UI isn't so obvious.)

We've just released v5.1.1 which includes this feature. It's online now, enjoy!

Thank you, Jens.

I have noticed you have after all implemented the idea quoted above in the last version and I now think - inspired by other kids' self-confidence here Last Digit Block! - a credit to me would be a deserved one.

Sure! Why don't you tell me your name (send me a private email), and I'll be happy to do so!

A bit late to the party, but I was confused about the output of the map block in your version: for the gray pixels it would output a pixel of [[55, 55, 55, A], [55, 55, 55, A], [55, 55, 55, A], 45], i.e. a pixel where the red, green, and blue values are the entire input pixel. I was surprised this worked at all.
Media_Map_Transparency_edited_by_jens script pic

I have not been following this thread lately, so I haven't seen your reply.

But, yes, you are right - see the discussion here.