Grey is not grey

Processing for Android
1

Current Processing 3, current Android mode:

  • App renders 3 rects with shades of grey and some alpha over each other (FFB0B0B0 under FF909090 under 10FFFFFF)
  • On-screen result should be pure grey - and it is under Windows.
  • It is not pure grey under Android (4.2 and 8.0 tested): It has an error in the green component:

chromatic%20error

RGB of the legend is 148 150 148. Curiously, the screenshot function of Processing, save(), generates files that do not show this chromatic error.

2

If the RGB value is 148, 150, 148, then Green has a higher value than the others. This might cause this behaviour. Did you try just using 148 in all?
Also, please add some code, so that we can examine and find the problem and a solution to your problem. Else we can only guess.

3

If the RGB value is 148, 150, 148, then Green has a higher value than the others. This might cause this behaviour

Sorry, I must have been unclear: 148 150 148 is the value picked from the emulator screen, i.e. the unexpectedly tinted result. My tablet has the same effect, somewhat poor colors, so it’s not an emulator issue.

The Windows version, build from the same source code (obviosuly with minor conditional OS-specific code, such as different display density), produces pure greys. Here they run next to each other, left Windows. As you can see, the greys are slightly off under Android:

sample
sample1218×493 124 KB

4

Oh, ok…still, some kind of code would be good… At least the lines where the color is used. Else we can’t do much more than guess :sweat_smile:
As far as i can tell, that might be either an error in the code (in the os-specific parts) or an intentional behaviour. Maybe grey doesn’t display good on most monitors, or tends toward seeming more red and blue, so they added a modifier for Android, though i doubt that would be the case…

Still, need code to say something specific…
Also, i might be wrong, but is it possible that all colors are slightly greenish? Maybe there is an almost invisible greenish overlay on top of the emulator…

5 
void setup() { }
void draw()
{
    background(255); noStroke();
    fill(0xFFB0B0B0); rect(0,   0, 100, 100);
    fill(0xFF909090); rect(10, 10, 80,  80 );
    fill(0x10FFFFFF); rect(20, 20, 60,  60 );  
}

Left Windows, right Android:

win%20vs%20android

As already mentioned, it can not be an emulator issue because colors are off on my tablet, too.

6

Yeah, i didn‘t mean only the emulator, But all Systems using android ^^. So your Emulator and your Tablet Would have the Same Problem.