Lua Scripting • Re: colors.lua

Code:

-- HSBLib-- Library of functions to covert between RGB and HSB color models-- Convert between 'rrr,ggg,bbb' and HEX forms of RGB-- Return the luminance (perceived lightness) of an RGB color-- Compiled and modified from various sources by JSMorley-- October 30, 2017-- Function :RGBtoHSB(arg)-- Argument :A string RGB color value in the form 'rrr,ggg,bbb'-- Returns :Three HSB values-- HSB hue as a percentage from 0.0-1.0-- *Multiply 360 with this value to obtain the degrees of hue--While hue is most often expressed as an integer, the fractional--amount can be important for precision in calculations--*Note that 0.0 (0 degrees) and 1.0 (360 degrees) are the same red hue--It's a counter-clockwise 360 degree "cylinder" of color--red->purple->blue->cyan->green->yellow->orange->red-- HSB saturation as a percentage from 0.0-1.0-- HSB brightness as a percentage from 0.0-1.0--*Note that this is the "brightness" of the color, and not the --"lightness" as in the HSL model. A color, particularly in the --blue range, can have 100% brightness and still be visibly quite dark.--Use the Luminance() function below to obtain "visible lightness"function RGBtoHSB(colorArg)colorArg = string.gsub(colorArg, ' ', '')inRed, inGreen, inBlue = string.match(colorArg, '(%d+),(%d+),(%d+)')percentR = ( inRed / 255 )percentG = ( inGreen / 255 )percentB = ( inBlue / 255 )colorMin = math.min( percentR, percentG, percentB )colorMax = math.max( percentR, percentG, percentB )deltaMax = colorMax - colorMincolorBrightness = colorMaxif (deltaMax == 0) thencolorHue = 0colorSaturation = 0elsecolorSaturation = deltaMax / colorMaxdeltaR = (((colorMax - percentR) / 6) + (deltaMax / 2)) / deltaMaxdeltaG = (((colorMax - percentG) / 6) + (deltaMax / 2)) / deltaMaxdeltaB = (((colorMax - percentB) / 6) + (deltaMax / 2)) / deltaMaxif (percentR == colorMax) thencolorHue = deltaB - deltaGelseif (percentG == colorMax) then colorHue = ( 1 / 3 ) + deltaR - deltaBelseif (percentB == colorMax) then colorHue = ( 2 / 3 ) + deltaG - deltaRendif ( colorHue < 0 ) then colorHue = colorHue + 1 endif ( colorHue > 1 ) then colorHue = colorHue - 1 endendreturn colorHue, colorSaturation, colorBrightnessend-- Function :HSBtoRGB(arg1, arg2, arg3)-- Argument:Three HSB values-- HSB hue as a percentage from 0.0-1.0-- HSB saturation as a percentage from 0.0-1.0-- HSB brightness as a percentage from 0.0-1.0-- Returns:Three RGB values-- Red value from 0-255-- Green value from 0-255-- Blue value from 0-255function HSBtoRGB(colorHue, colorSaturation, colorBrightness)degreesHue = colorHue * 6if (degreesHue == 6) then degreesHue = 0 enddegreesHue_int = math.floor(degreesHue)percentSaturation1 = colorBrightness * (1 - colorSaturation)percentSaturation2 = colorBrightness * (1 - colorSaturation * (degreesHue - degreesHue_int))percentSaturation3 = colorBrightness * (1 - colorSaturation * (1 - (degreesHue - degreesHue_int)))if (degreesHue_int == 0)  thenpercentR = colorBrightnesspercentG = percentSaturation3percentB = percentSaturation1elseif (degreesHue_int == 1) thenpercentR = percentSaturation2percentG = colorBrightnesspercentB = percentSaturation1elseif (degreesHue_int == 2) thenpercentR = percentSaturation1percentG = colorBrightnesspercentB = percentSaturation3elseif (degreesHue_int == 3) thenpercentR = percentSaturation1percentG = percentSaturation2percentB = colorBrightnesselseif (degreesHue_int == 4) thenpercentR = percentSaturation3percentG = percentSaturation1percentB = colorBrightnesselsepercentR = colorBrightnesspercentG = percentSaturation1percentB = percentSaturation2end outRed = Round(percentR * 255)outGreen = Round(percentG * 255)outBlue = Round(percentB * 255)return outRed, outGreen, outBlueend-- Function :HEXtoRGB(arg)-- Argument:Hex string value in the form '#cccccc' or 'cccccc'-- * HEX shorthand is supported-- Returns:Three RGB values-- Red value from 0-255-- Green value from 0-255-- Blue value from 0-255function HEXtoRGB(hexArg)hexArg = hexArg:gsub('#','')if(string.len(hexArg) == 3) thenreturn tonumber('0x'..hexArg:sub(1,1)) * 17, tonumber('0x'..hexArg:sub(2,2)) * 17, tonumber('0x'..hexArg:sub(3,3)) * 17elseif(string.len(hexArg) == 6) thenreturn tonumber('0x'..hexArg:sub(1,2)), tonumber('0x'..hexArg:sub(3,4)), tonumber('0x'..hexArg:sub(5,6))elsereturn 0, 0, 0endend-- Function :RGBtoHEX(arg1, arg2, arg3)-- Argument:Three RGB values-- Red value from 0-255-- Green value from 0-255-- Blue value from 0-255-- Returns:String hex value in the form 'cccccc'function RGBtoHEX(redArg, greenArg, blueArg)return string.format('%.2x%.2x%.2x', redArg, greenArg, blueArg)end-- Function:ColorLumens(arg)-- Argument:A string RGB color value in the form 'rrr,ggg,bbb'-- Returns:Luminance (perceived lightness) as a percentage from 0.0-1.0 --*A ratio of 5:1 on larger items and 10:1 on smaller text is--recommended as a "contrast" between foreground and--background colors to be comfortable to the human eyefunction ColorLumens(colorArg)colorArg = string.gsub(colorArg, ' ', '')inRed, inGreen, inBlue = string.match(colorArg, '(%d+),(%d+),(%d+)')curLumens = Round((math.sqrt(0.299 * inRed^2 + 0.587 * inGreen^2 + 0.114 * inBlue^2) / 255) * 100)return curLumensend-- Utility functionsfunction Clamp(numArg, lowArg, highArg)return math.max(lowArg, math.min(highArg, numArg))endfunction Round(numArg, decimalsArg)local mult = 10 ^ (decimalsArg or 0)if numArg >= 0 thenreturn math.floor(numArg * mult + 0.5) / multelsereturn math.ceil(numArg * mult - 0.5) / multendend