what was yesterday’s drracket logo about?

@zenspider what did it look like?

Turtle with red and blue shell

https://en.wikipedia.org/wiki/Kamehameha_Day

nice

thanks

lol, I thought June 11 was just an important day for #lang honu https://www.cs.utah.edu/~rafkind/papers/honu-2012.pdf

I’m not quite understanding the documentation on this http://docs.racket-lang.org/draw/bitmap_.html

How do I set individual pixels to be a certain color in a bitmap?

@mrm: set-argb-pixels, I think

What’s the ‘pixels’ argument?

it’s documented here: http://docs.racket-lang.org/draw/bitmap-dc_.html#%28meth._%28%28%28lib._racket%2Fdraw..rkt%29._bitmap-dc~25%29._set-argb-pixels%29%29

I saw the documentation for it. I don’t understand what it’s saying.

four consecutive bytes represent a single pixel: (alpha, red, green, blue)

if you want to set a single pixel, pass 1 for width and height, and provide a 4-byte byte array

Ah good, width and height you color a grid of pixels at the same time?

@jaz Thanks

you can set a block of pixels all at once, yes, starting at (x, y)

The coordinates are from the upper left corner, right?

yes

says “The pixels are in row-major order, left to right then top to bottom.”

so yep

Thanks.

I wrote a quick and dirty thing with pict a couple weeks ago to provide visualizations of some experimental math thing for some colleges, and now they kind of are depending on them a bit more regularly, so I’m trying to make it more efficient. I haven’t done much with graphics or pictures prior to this, so all the stuff about alphas and back-channels and whatnot was making it kind of hard to parse.

(context)

Anyways, thanks for the help :slightly_smiling_face:

no clue

search for the-bitmap-spec in the racket source

drracket/drracket/private/honu-logo.rkt etc

Ah. Of course it wouldn’t just be a set of png files… :upside_down_face: