[Cyan]<CedarChest6.1>ColorTool>CGColorWithCIE.mesa!1

CGColorWithCIE.mesa

Last edited by Maureen Stone, June 21, 1985 1:51:34 pm PDT

Last edited by Doug Wyatt, August 31, 1982 2:50 pm

Last Edited by: Beach, February 13, 1984 2:20:49 pm PST

Last Edited by: Naiman, June 14, 1985 5:25:29 pm PDT

DIRECTORY

ImagerColor USING [RGB];

CGColorWithCIE: CEDAR DEFINITIONS = {

ColorTag: TYPE = {rgb, stipple};

Color: TYPE = RECORD[tag: ColorTag, r,g,b: [0..256)];

GetStipple: PROC[color: Color] RETURNS[CARDINAL] = INLINE { RETURN[color.g*256+color.b] };
-- get a color's stipple pattern, assuming color.tag = stipple

The following convert between (hue, saturation, value) or (hue, saturation, lightness) and (red, green, blue).

All REALs except h should be in the range [0..1].

--h=undefined means it's a gray.

InvalidColor, Uninitialized: SIGNAL;

undefined: REAL = -1;

HSVToRGB: PROC[h, s, v: REAL] RETURNS[r, g, b: REAL];

RGBToHSV: PROC[r, g, b: REAL] RETURNS[h, s, v: REAL];

--HSV hexacone model.

HSLToRGB: PROC[h, s, l: REAL] RETURNS[r, g, b: REAL];

RGBToHSL: PROC[r, g, b: REAL] RETURNS[h, s, l: REAL];

--HSL double hexacone model.

The following convert between (intensity, in-phase, quadrature) and (red, green, blue).

YIQToRGB: PROC[y, i, q: REAL] RETURNS[r, g, b: REAL];

RGBToYIQ: PROC[r, g, b: REAL] RETURNS[y, i, q: REAL];

-- NTSC model.

The following convert between (achromatic, red-green, yellow-blue) and (red, green, blue).

ARgYbToRGB: PROC[a, rg, yb: REAL] RETURNS[r, g, b: REAL];

RGBToARgYb: PROC[r, g, b: REAL] RETURNS[a, rg, yb: REAL];

-- opponent colors model.

The following convert between (red, green, blue) and (x,y) chromaticity coordinates.

Initialize the transform with x,y for red, green blue plus Y. Y can default to 1 if you're not matching the monitor to anything else.

CIEToRGB and RGBToCIE will signal Uninitialized if InitCIE has not been called

InitCIE: PROC[xr,yr,xg,yg,xb,yb: REAL, whiteY: REAL ← 1];

add more info hear for real cie. Need two more values?

PhosphorType: TYPE = {long,normal};

InitDefaultCIE: PROC[type: PhosphorType ← long];

default values for long and short persistance phosphors

GetDefaultValues: PROC[type: PhosphorType] RETURNS[xr,yr,xg,yg,xb,yb: REAL];

SetDefaultValues: PROC[xr,yr,xg,yg,xb,yb: REAL, type: PhosphorType];

add more info hear for real cie

CIEToRGB: PROC[x,y, Y: REAL] RETURNS[r, g, b: REAL];

GetMaxY: PUBLIC PROC[x,y: REAL] RETURNS[Y: REAL];

used to clip values of Y for CIEToRGB

RGBToCIE: PROC[r, g, b: REAL] RETURNS [x,y, Y: REAL];

The following compute the contrasting color in each color space.

ContrastInRGB: PROC[rgb: ImagerColor.RGB] RETURNS[rgbContrast: ImagerColor.RGB];

ContrastInHSV: PROC[rgb: ImagerColor.RGB] RETURNS[hsvContrast: ImagerColor.RGB];

ContrastInHSL: PROC[rgb: ImagerColor.RGB] RETURNS[hslContrast: ImagerColor.RGB];

ContrastInYIQ: PROC[rgb: ImagerColor.RGB] RETURNS[yiqContrast: ImagerColor.RGB];

ContrastInARgYb: PROC[rgb: ImagerColor.RGB] RETURNS[argybContrast: ImagerColor.RGB];