OOColor.m

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/*
 
OOColor.m
 
Oolite
Copyright (C) 2004-2013 Giles C Williams and contributors
 
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
 
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
MA 02110-1301, USA.
 
*/
 
#import "OOColor.h"
#import "OOCollectionExtractors.h"
#import "OOMaths.h"
 
 
@implementation OOColor
 
// Set methods are internal, because OOColor is immutable (as seen from outside).
- (void) setRed:(float)r green:(float)g blue:(float)b alpha:(float)a
{
    rgba[0] = r;
    rgba[1] = g;
    rgba[2] = b;
    rgba[3] = a;
}
 
 
- (void) setHue:(float)h saturation:(float)s brightness:(float)b alpha:(float)a
{
    rgba[3] = a;
    if (s == 0.0f)
    {
        rgba[0] = rgba[1] = rgba[2] = b;
        return;
    }
    float f, p, q, t;
    int i;
    h = fmod(h, 360.0f);
    if (h < 0.0) h += 360.0f;
    h /= 60.0f;
    
    i = floor(h);
    f = h - i;
    p = b * (1.0f - s);
    q = b * (1.0f - (s * f));
    t = b * (1.0f - (s * (1.0f - f)));
    
    switch (i)
    {
        case 0:
            rgba[0] = b;    rgba[1] = t;    rgba[2] = p;    break;
        case 1:
            rgba[0] = q;    rgba[1] = b;    rgba[2] = p;    break;
        case 2:
            rgba[0] = p;    rgba[1] = b;    rgba[2] = t;    break;
        case 3:
            rgba[0] = p;    rgba[1] = q;    rgba[2] = b;    break;
        case 4:
            rgba[0] = t;    rgba[1] = p;    rgba[2] = b;    break;
        case 5:
            rgba[0] = b;    rgba[1] = p;    rgba[2] = q;    break;
    }
}
 
 
- (id) copyWithZone:(NSZone *)zone
{
    // Copy is implemented as retain since OOColor is immutable.
    return [self retain];
}
 
 
+ (OOColor *) colorWithHue:(float)hue saturation:(float)saturation brightness:(float)brightness alpha:(float)alpha
{
    OOColor* result = [[OOColor alloc] init];
    [result setHue:360.0f * hue saturation:saturation brightness:brightness alpha:alpha];
    return [result autorelease];
}
 
 
+ (OOColor *) colorWithRed:(float)red green:(float)green blue:(float)blue alpha:(float)alpha
{
    OOColor* result = [[OOColor alloc] init];
    [result setRed:red green:green blue:blue alpha:alpha];
    return [result autorelease];
}
 
 
+ (OOColor *) colorWithWhite:(float)white alpha:(float)alpha
{
    return [OOColor colorWithRed:white green:white blue:white alpha:alpha];
}
 
 
+ (OOColor *) colorWithRGBAComponents:(OORGBAComponents)components
{
    return [self colorWithRed:components.r
                        green:components.g
                         blue:components.b
                        alpha:components.a];
}
 
 
+ (OOColor *) colorWithHSBAComponents:(OOHSBAComponents)components
{
    return [self colorWithHue:components.h / 360.0f
                   saturation:components.s
                   brightness:components.b
                        alpha:components.a];
}
 
 
+ (OOColor *) colorWithDescription:(id)description
{
    return [self colorWithDescription:description saturationFactor:1.0f];
}
 
 
+ (OOColor *) colorWithDescription:(id)description saturationFactor:(float)factor
{
    NSDictionary            *dict = nil;
    OOColor                 *result = nil;
    
    if (description == nil) return nil;
    
    if ([description isKindOfClass:[OOColor class]])
    {
        result = [[description copy] autorelease];
    }
    else if ([description isKindOfClass:[NSString class]])
    {
        if ([description hasSuffix:@"Color"])
        {
            // +fooColor selector
            SEL selector = NSSelectorFromString(description);
            if ([self respondsToSelector:selector])  result = [self performSelector:selector];
        }
        else
        {
            // Some other string
            result = [self colorFromString:description];
        }
    }
    else if ([description isKindOfClass:[NSArray class]])
    {
        result = [self colorFromString:[description componentsJoinedByString:@" "]];
    }
    else if ([description isKindOfClass:[NSDictionary class]])
    {
        dict = description; // Workaround for gnu-gcc's more agressive "multiple methods named..." warnings.
        
        if ([dict objectForKey:@"hue"] != nil)
        {
            // Treat as HSB(A) dictionary
            float h = [dict oo_floatForKey:@"hue"];
            float s = [dict oo_floatForKey:@"saturation" defaultValue:1.0f];
            float b = [dict oo_floatForKey:@"brightness" defaultValue:-1.0f];
            if (b < 0.0f)  b = [dict oo_floatForKey:@"value" defaultValue:1.0f];
            float a = [dict oo_floatForKey:@"alpha" defaultValue:-1.0f];
            if (a < 0.0f)  a = [dict oo_floatForKey:@"opacity" defaultValue:1.0f];
            
            // Not "result =", because we handle the saturation scaling here to allow oversaturation.
            return [OOColor colorWithHue:h / 360.0f saturation:s * factor brightness:b alpha:a];
        }
        else
        {
            // Treat as RGB(A) dictionary
            float r = [dict oo_floatForKey:@"red"];
            float g = [dict oo_floatForKey:@"green"];
            float b = [dict oo_floatForKey:@"blue"];
            float a = [dict oo_floatForKey:@"alpha" defaultValue:-1.0f];
            if (a < 0.0f)  a = [dict oo_floatForKey:@"opacity" defaultValue:1.0f];
            
            result = [OOColor colorWithRed:r green:g blue:b alpha:a];
        }
    }
    
    if (factor != 1.0f && result != nil)
    {
        float h, s, b, a;
        [result getHue:&h saturation:&s brightness:&b alpha:&a];
        h *= 1.0 / 360.0f;  // See note in header.
        s *= factor;
        result = [self colorWithHue:h saturation:s brightness:b alpha:a];
    }
    
    return result;
}
 
 
+ (OOColor *) brightColorWithDescription:(id)description
{
    OOColor *color = [OOColor colorWithDescription:description];
    if (color == nil || 0.5f <= [color brightnessComponent])  return color;
    
    return [OOColor colorWithHue:[color hueComponent] / 360.0f saturation:[color saturationComponent] brightness:0.5f alpha:1.0f];
}
 
 
+ (OOColor *) colorFromString:(NSString*) colorFloatString
{
    float           rgbaValue[4] = { 0.0f, 0.0f, 0.0f, 1.0f };
    NSScanner       *scanner = [NSScanner scannerWithString:colorFloatString];
    float           factor = 1.0f;
    int             i;
    
    for (i = 0; i != 4; ++i)
    {
        if (![scanner scanFloat:&rgbaValue[i]])
        {
            // Less than three floats or non-float, can't parse -> quit
            if (i < 3) return nil;
            
            // If we get here, we only got three components. Make sure alpha is at correct scale:
            rgbaValue[3] /= factor;
        }
        if (1.0f < rgbaValue[i]) factor = 1.0f / 255.0f;
    }
    
    return [OOColor colorWithRed:rgbaValue[0] * factor green:rgbaValue[1] * factor blue:rgbaValue[2] * factor alpha:rgbaValue[3] * factor];
}
 
 
+ (OOColor *) blackColor        // 0.0 white
{
    return [OOColor colorWithWhite:0.0f alpha:1.0f];
}
 
 
+ (OOColor *) darkGrayColor     // 0.333 white
{
    return [OOColor colorWithWhite:1.0f/3.0f alpha:1.0f];
}
 
 
+ (OOColor *) lightGrayColor    // 0.667 white
{
    return [OOColor colorWithWhite:2.0f/3.0f alpha:1.0f];
}
 
 
+ (OOColor *) whiteColor        // 1.0 white
{
    return [OOColor colorWithWhite:1.0f alpha:1.0f];
}
 
 
+ (OOColor *) grayColor         // 0.5 white
{
    return [OOColor colorWithWhite:0.5f alpha:1.0f];
}
 
 
+ (OOColor *) redColor          // 1.0, 0.0, 0.0 RGB
{
    return [OOColor colorWithRed:1.0f green:0.0f blue:0.0f alpha:1.0f];
}
 
 
+ (OOColor *) greenColor        // 0.0, 1.0, 0.0 RGB
{
    return [OOColor colorWithRed:0.0f green:1.0f blue:0.0f alpha:1.0f];
}
 
 
+ (OOColor *) blueColor         // 0.0, 0.0, 1.0 RGB
{
    return [OOColor colorWithRed:0.0f green:0.0f blue:1.0f alpha:1.0f];
}
 
 
+ (OOColor *) cyanColor         // 0.0, 1.0, 1.0 RGB
{
    return [OOColor colorWithRed:0.0f green:1.0f blue:1.0f alpha:1.0f];
}
 
 
+ (OOColor *) yellowColor       // 1.0, 1.0, 0.0 RGB
{
    return [OOColor colorWithRed:1.0f green:1.0f blue:0.0f alpha:1.0f];
}
 
 
+ (OOColor *) magentaColor      // 1.0, 0.0, 1.0 RGB
{
    return [OOColor colorWithRed:1.0f green:0.0f blue:1.0f alpha:1.0f];
}
 
 
+ (OOColor *) orangeColor       // 1.0, 0.5, 0.0 RGB
{
    return [OOColor colorWithRed:1.0f green:0.5f blue:0.0f alpha:1.0f];
}
 
 
+ (OOColor *) purpleColor       // 0.5, 0.0, 0.5 RGB
{
    return [OOColor colorWithRed:0.5f green:0.0f blue:0.5f alpha:1.0f];
}
 
 
+ (OOColor *)brownColor         // 0.6, 0.4, 0.2 RGB
{
    return [OOColor colorWithRed:0.6f green:0.4f blue:0.2f alpha:1.0f];
}
 
 
+ (OOColor *) clearColor        // 0.0 white, 0.0 alpha
{
    return [OOColor colorWithWhite:0.0f alpha:0.0f];
}
 
 
- (OOColor *) blendedColorWithFraction:(float)fraction ofColor:(OOColor *)color
{
    float   rgba1[4];
    [color getRed:&rgba1[0] green:&rgba1[1] blue:&rgba1[2] alpha:&rgba1[3]];
    
    OOColor *result = [[OOColor alloc] init];
    [result setRed:OOLerp(rgba[0], rgba1[0], fraction)
             green:OOLerp(rgba[1], rgba1[1], fraction)
              blue:OOLerp(rgba[2], rgba1[2], fraction)
             alpha:OOLerp(rgba[3], rgba1[3], fraction)];
    
    return [result autorelease];
}
 
 
- (NSString *) descriptionComponents
{
    return [NSString stringWithFormat:@"%g, %g, %g, %g", rgba[0], rgba[1], rgba[2], rgba[3]];
}
 
 
// Get the red, green, or blue components.
- (float) redComponent
{
    return rgba[0];
}
 
 
- (float) greenComponent
{
    return rgba[1];
}
 
 
- (float) blueComponent
{
    return rgba[2];
}
 
 
- (void) getRed:(float *)red green:(float *)green blue:(float *)blue alpha:(float *)alpha
{
    NSParameterAssert(red != NULL && green != NULL && blue != NULL && alpha != NULL);
    
    *red = rgba[0];
    *green = rgba[1];
    *blue = rgba[2];
    *alpha = rgba[3];
}
 
 
- (OORGBAComponents) rgbaComponents
{
    OORGBAComponents c = { rgba[0], rgba[1], rgba[2], rgba[3] };
    return c;
}
 
 
- (BOOL) isBlack
{
    return rgba[0] == 0.0f && rgba[1] == 0.0f && rgba[2] == 0.0f;
}
 
 
- (BOOL) isWhite
{
    return rgba[0] == 1.0f && rgba[1] == 1.0f && rgba[2] == 1.0f && rgba[3] == 1.0f;
}
 
 
// Get the components as hue, saturation, or brightness.
- (float) hueComponent
{
    float maxrgb = (rgba[0] > rgba[1])? ((rgba[0] > rgba[2])? rgba[0]:rgba[2]):((rgba[1] > rgba[2])? rgba[1]:rgba[2]);
    float minrgb = (rgba[0] < rgba[1])? ((rgba[0] < rgba[2])? rgba[0]:rgba[2]):((rgba[1] < rgba[2])? rgba[1]:rgba[2]);
    float delta = maxrgb - minrgb + 0.0001f;
    float fRed = rgba[0], fGreen = rgba[1], fBlue = rgba[2];
    float hue = 0.0f;
    if (maxrgb == fRed && fGreen >= fBlue)
    {
        hue = 60.0f * (fGreen - fBlue) / delta;
    }
    else if (maxrgb == fRed && fGreen < fBlue)
    {
        hue = 60.0f * (fGreen - fBlue) / delta + 360.0f;
    }
    else if (maxrgb == fGreen)
    {
        hue = 60.0f * (fBlue - fRed) / delta + 120.0f;
    }
    else if (maxrgb == fBlue)
    {
        hue = 60.0f * (fRed - fGreen) / delta + 240.0f;
    }
    return hue;
}
 
- (float) saturationComponent
{
    float maxrgb = (rgba[0] > rgba[1])? ((rgba[0] > rgba[2])? rgba[0]:rgba[2]):((rgba[1] > rgba[2])? rgba[1]:rgba[2]);
    float minrgb = (rgba[0] < rgba[1])? ((rgba[0] < rgba[2])? rgba[0]:rgba[2]):((rgba[1] < rgba[2])? rgba[1]:rgba[2]);
    return maxrgb == 0.0f ? 0.0f : (1.0f - (minrgb / maxrgb));
}
 
- (float) brightnessComponent
{
    float maxrgb = (rgba[0] > rgba[1])? ((rgba[0] > rgba[2])? rgba[0]:rgba[2]):((rgba[1] > rgba[2])? rgba[1]:rgba[2]);
    return maxrgb;
}
 
- (void) getHue:(float *)hue saturation:(float *)saturation brightness:(float *)brightness alpha:(float *)alpha
{
    NSParameterAssert(hue != NULL && saturation != NULL && brightness != NULL && alpha != NULL);
    
    *alpha = rgba[3];
    
    float fRed = rgba[0], fGreen = rgba[1], fBlue = rgba[2];
    float maxrgb = fmax(fRed, fmax(fGreen, fBlue));
    float minrgb = fmin(fRed, fmin(fGreen, fBlue));
    float delta = maxrgb - minrgb + 0.0001f;
    float h = 0.0f;
    if (maxrgb == fRed && fGreen >= fBlue)
    {
        h = 60.0f * (fGreen - fBlue) / delta;
    }
    else if (maxrgb == fRed && fGreen < fBlue)
    {
        h = 60.0f * (fGreen - fBlue) / delta + 360.0f;
    }
    else if (maxrgb == fGreen)
    {
        h = 60.0f * (fBlue - fRed) / delta + 120.0f;
    }
    else if (maxrgb == fBlue)
    {
        h = 60.0f * (fRed - fGreen) / delta + 240.0f;
    }
    
    float s = (maxrgb == 0.0f) ? 0.0f : (1.0f - (minrgb / maxrgb));
    
    *hue = h;
    *saturation = s;
    *brightness = maxrgb;
}
 
 
- (OOHSBAComponents) hsbaComponents
{
    OOHSBAComponents c;
    [self getHue:&c.h
      saturation:&c.s
      brightness:&c.b
           alpha:&c.a];
    return c;
}
 
 
// Get the alpha component.
- (float) alphaComponent
{
    return rgba[3];
}
 
 
- (OOColor *) premultipliedColor
{
    if (rgba[3] == 1.0f)  return [[self retain] autorelease];
    return [OOColor colorWithRed:rgba[0] * rgba[3]
                           green:rgba[1] * rgba[3]
                            blue:rgba[2] * rgba[3]
                           alpha:1.0f];
}
 
 
- (OOColor *) colorWithBrightnessFactor:(float)factor
{
    return [OOColor colorWithRed:OOClamp_0_1_f(rgba[0] * factor)
                           green:OOClamp_0_1_f(rgba[1] * factor)
                            blue:OOClamp_0_1_f(rgba[2] * factor)
                           alpha:rgba[3]];
}
 
 
- (NSArray *) normalizedArray
{
    float r, g, b, a;
    [self getRed:&r green:&g blue:&b alpha:&a];
    return [NSArray arrayWithObjects:
        [NSNumber numberWithFloat:r],
        [NSNumber numberWithFloat:g],
        [NSNumber numberWithFloat:b],
        [NSNumber numberWithFloat:a],
        nil];
}
 
 
- (NSString *) rgbaDescription
{
    return OORGBAComponentsDescription([self rgbaComponents]);
}
 
 
- (NSString *) hsbaDescription
{
    return OOHSBAComponentsDescription([self hsbaComponents]);
}
 
@end
 
 
NSString *OORGBAComponentsDescription(OORGBAComponents components)
{
    return [NSString stringWithFormat:@"{%.3g, %.3g, %.3g, %.3g}", components.r, components.g, components.b, components.a];
}
 
 
NSString *OOHSBAComponentsDescription(OOHSBAComponents components)
{
    return [NSString stringWithFormat:@"{%i, %.3g, %.3g, %.3g}", (int)components.h, components.s, components.b, components.a];
}