PIXON_P Alpha blending

[cyrille de brébisson]

Hello,

Han is correct in saying that doing repeat alpha will "max out" following the sequence Un+1=((256-a)*Un+a*c2)/256, which has an asymptotic value which is not 255...

Depending on the number of drawn pixels, it might be better to create a matrix of numbers that you increment "off screen", and that you then display.
The fastest, assuming that you do not get over 65536 iterations per points might be to use a string...
Create a string of size 320*240, fill it with 0s str(i):=0; and then inc the item of interest on each iteration str(y*320+x+1):= str(y*320+x+1)+1;
then display the content of the string.

Cyrille