On 28-07-2015, at 5:24 AM, Bert Freudenberg <bert at freudenbergs.de> wrote:
> sqUnixX11.c: copyImage16To16() should do it. If you replace the stRNMask/stRShift variables with constants it might even be reasonably efficient. ARM SIMD code would be better, obviously.

Oh, it certainly would - indeed it does since some devious ARM simd code is hooked up on ARM platforms.

> 
> Or are you talking about Smalltalk code? A single bitblt copy with a suitable color map should do it.

Since it’s only an 8x8 array of ws28-something LEDs that has to be written by opening /dev/fb*, then writing to the ‘file’, then closing the file to make it actually display, performance of the conversion is not a huge problem. Right now I can display scrolling paragraphs, arbitrary screen-grabs, whatever, and it’s now a case of deciding what people want to display rather than how to display.
I did discover to my surprise that some font glyphs are 16bpp with antialiasing that makes for really surprising displays on a physically large 8x8 display. It took a while to work out what was going on there...

tim
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