## a working setColor compatibilty multiplier

Tricky
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### Re: a working setColor compatibilty multiplier

For me the change from 255 to 1 didn't make sense anyway.
Yeah 255 is indeed the max color value due to 255 being the decimal equivalent to binary 1111111
For me it works very very confusing since all graphic manipulation programs I have (as well as other programming tools I use) use a 0-255 scale, so you can imagine I was NOT amused about this change, and if it really needed to be done a DIFFERENT FUNCTION handling the 0-1 scale could be desirable (WITHOUT deprecating the original function!!!!)

Now I was "blessed" by laziness. I fell asleep every time I had to type love.graphics.setColor so I had a "color=love.graphics.setColor" present. All I needed to do was adding a version checker that would divide all values by 255 if version 11 or higher was detected. Saved me a lot of "code rot". The speed in which drastic changes take place on LÖVE, makes me wanna avoid all original direct love calls but use my own in stead, so I only need to add a version checker and the different code that I would need and voilà everything works.... again... :-/

Oh well...

Nixola
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### Re: a working setColor compatibilty multiplier

There are more ways to represent colours, some of which exceed 255.
lf = love.filesystem
ls = love.sound
la = love.audio
lp = love.physics
li = love.image
lg = love.graphics

s-ol
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### Re: a working setColor compatibilty multiplier

Tricky wrote:
Sat May 26, 2018 2:53 pm
For me the change from 255 to 1 didn't make sense anyway.
Yeah 255 is indeed the max color value due to 255 being the decimal equivalent to binary 1111111
For me it works very very confusing since all graphic manipulation programs I have (as well as other programming tools I use) use a 0-255 scale, so you can imagine I was NOT amused about this change, and if it really needed to be done a DIFFERENT FUNCTION handling the 0-1 scale could be desirable (WITHOUT deprecating the original function!!!!)

Now I was "blessed" by laziness. I fell asleep every time I had to type love.graphics.setColor so I had a "color=love.graphics.setColor" present. All I needed to do was adding a version checker that would divide all values by 255 if version 11 or higher was detected. Saved me a lot of "code rot". The speed in which drastic changes take place on LÖVE, makes me wanna avoid all original direct love calls but use my own in stead, so I only need to add a version checker and the different code that I would need and voilà everything works.... again... :-/

Oh well...

Code: Select all

-- compat.lua
local _setColor = love.graphics.setColor
function love.graphics.setColor(r, g, b, a)
return _setColor(r/255, g/255, b/255, a and a/255)
end

this is Lua after all.

0-1 is semantically more correct, and as Nixola points out, more general than 0-255. Some colorspaces have 0-360 for example.
Having the values normalized is also mathematically ideal, it means that you can multiply components properly.
If you are working with 0-255 values internally then you have to take care to divide by 255 when you do thinks like multiplying colors or exponentials etc.

s-ol.nu /blog  -  p.s-ol.be /st8.lua  -  g.s-ol.be /gtglg /curcur

Code: Select all

print( type(love) )
if false then
baby:hurt(me)
end

Tricky
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Location: Breda, the Netherlands
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### Re: a working setColor compatibilty multiplier

s-ol wrote:
Mon May 28, 2018 9:05 am
Tricky wrote:
Sat May 26, 2018 2:53 pm
For me the change from 255 to 1 didn't make sense anyway.
Yeah 255 is indeed the max color value due to 255 being the decimal equivalent to binary 1111111
For me it works very very confusing since all graphic manipulation programs I have (as well as other programming tools I use) use a 0-255 scale, so you can imagine I was NOT amused about this change, and if it really needed to be done a DIFFERENT FUNCTION handling the 0-1 scale could be desirable (WITHOUT deprecating the original function!!!!)

Now I was "blessed" by laziness. I fell asleep every time I had to type love.graphics.setColor so I had a "color=love.graphics.setColor" present. All I needed to do was adding a version checker that would divide all values by 255 if version 11 or higher was detected. Saved me a lot of "code rot". The speed in which drastic changes take place on LÖVE, makes me wanna avoid all original direct love calls but use my own in stead, so I only need to add a version checker and the different code that I would need and voilà everything works.... again... :-/

Oh well...

Code: Select all

-- compat.lua
local _setColor = love.graphics.setColor
function love.graphics.setColor(r, g, b, a)
return _setColor(r/255, g/255, b/255, a and a/255)
end

this is Lua after all.

0-1 is semantically more correct, and as Nixola points out, more general than 0-255. Some colorspaces have 0-360 for example.
Having the values normalized is also mathematically ideal, it means that you can multiply components properly.
If you are working with 0-255 values internally then you have to take care to divide by 255 when you do thinks like multiplying colors or exponentials etc.
I basically went a bit like this

Code: Select all


--[[ This is fake code, so it won't work, it was just to get the picture]]
if version<11 then
color=love.graphics.setcolor
else
color=function(r,g,b,a)
love.graphics.setcolor(r/255,g/255,b/255,a/255)
end
end


That is fake code, it was just to get the picture, and this way it works on both 0.10 as on 11.x
Now I wonder what good a 0-360 scale would do since 0-255 already creates more colors a human eye can distinguish (not to mention the only color value I've ever seen in a 0-360 scale is the hue value in hsv coloring, due to 360 degrees making the full color circle, but if it did make sense the change the way it was done, was just way ugly, making all LÖVE programs suffer from code-rot in the process.
I also wonder if having to divide all colors by 255 all the time doesn't lead to performance issues in more complex programs...

Well, I already coded when colors where still in a 256-color-palette with each palette slot only having a 0-63 scale for colors, and I do remember that it was rather a big switch to go to a 0-255 scale, not to mention, getting rid of palettes altogether, but I could see the sense back then. Now it just seems like, well, we can do it, so why don't we.... Figures ....

holywyvern
Prole
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### Re: a working setColor compatibilty multiplier

You can do it simpler:

Code: Select all

local lib = {}

if love._version_major < 11 then
lib.setColor = love.graphics.setColor
lib.getColor = love.graphics.getColor
else
lib.setColor = function (r, g, b, a)
love.graphics.setColor(r / 255, g / 255, b / 255, (a or 255) / 255)
end
lib.getColor = function ()
local r, g, b, a = love.graphics.getColor()
return r * 255, g * 255, b * 255, a * 255
end
end

return lib


You could override love.graphics.getColor and love.graphics.setColor directly, but that's your choice to make.

grump
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Posts: 586
Joined: Sat Jul 22, 2017 7:43 pm

### Re: a working setColor compatibilty multiplier

holywyvern wrote:
Mon Jun 04, 2018 12:42 pm

Code: Select all

  lib.getColor = function ()
local r, g, b, a = love.graphics.getColor()
return r * 255, g * 255, b * 255, a * 255
end

That doesn't work as expected, because getColor returns truncated values.

love.graphics.setColor is also not the only function that takes colors - there's plenty more in several interfaces that can't be all replaced so easily. For a complete solution that takes care of everything for you, use this:

Code: Select all

if love._version_major >= 11 then
require('cindy').applyPatch() -- https://github.com/megagrump/cindy
end
This makes love.graphics, Shader, ImageData, SpriteBatch and all other relevant things work with the [0-255] range again. Or you can omit applyPatch() and use the provided alternative functions (e. g. setColorBytes) instead that work with the old range.

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