Pixel Color Test

[johnno56]

Marcus,

I am still confused in regards to "how" the pixel() command works.

Are you able to explain the output produced? (see attached image)

   

Regards

J

[1micha.elok]

This is an unofficial answer ... 
(unofficial = might be incomplete or even confusing .... lol ....)

pixel(x,y) returns the color at position (x, y) as an array [r, g, b, a]

Code:

'pixel(x,y) returns the color at position (x, y) as an array [r, g, b, a]
getcolor=pixel(150,150)
wln getcolor
wln
write "RGBA "
for i = 0 to 3
    write getcolor[i]+" "
next

   
click the image to zoom in

[johnno56]

Ah... this is where my confusion kicks in... over the many years of using multiple forms of Basic, the commands for testing a colour at x,y usual produces a single integer value. If memory serves correctly, N6 handled integer values using "pixeli(x,y)"

So, as N7 currently stands, if I want to check the colour of a pixel, I will need to check all R, G, B and A values of pixel(x,y)? or am I still confused... Would it not be simpler to add pixeli() command to N7?

[Marcus]

Ah... this is where my confusion kicks in... over the many years of using multiple forms of Basic, the commands for testing a colour at x,y usual produces a single integer value. If memory serves correctly, N6 handled integer values using "pixeli(x,y)"

So, as N7 currently stands, if I want to check the colour of a pixel, I will need to check all R, G, B and A values of pixel(x,y)? or am I still confused... Would it not be simpler to add pixeli() command to N7?

The problem is that n7 has no integer type, all numbers are 64 bit doubles (floating point). A 64 bit double can correctly represent any signed 32 bit integer. But what you need when storing an RGBA value is a 32 bit UNSIGNED integer with a much larger (positive) range. Can a double handle that, or ... does it even matter if it's just used for a pixeli function? I'm not sure. Do we also want to be able to simulate bit operators? Would that work? I'm not sure

I'll give it a shot anyhow

[Marcus]

I released a new version with the 'pixeli' function and 'set colori' command. I didn't add any bitwise operators but provided some helper functions in the release post. Hope it helps!

[johnno56]

Cool... I am about to turn in for the evening... I will "take it out for a spin" in the morning... Your efforts are appreciated. Thank you.