com.levigo.util.base
Class Colors

java.lang.Object
  com.levigo.util.base.Colors

public class Colors
extends Object

A bunch of static utility methods useful in conjunction with colors.

Method Summary

static Color	alpha(Color c, float alpha) Create a new color identical to the given one, but having its alpha value replaced with the given one.
static Color	alpha(Color c, int alpha) Create a new color identical to the given one, but having its alpha value replaced with the given one.
static Color	alphaComposite(Color fg, Color bg) Composite two colors using alpha compositing.
static Color	fromHSB(float[] hsl) Convert the given color in the HSB (sometimes called HSL) color model into a Color in the color space sRGB.
static Color	fromHSB(float h, float s, float b) Convert the given color in the HSB (sometimes called HSL) color model into a Color in the color space sRGB.
static Color	invert(Color c) Create a new color which is the inverse of the given one.
static float	luminance(Color c) Return the color's luminance normalized to the range [0,1].
static float	luminanceContrast(Color c1, Color c2) Return luminance contrast between the two colors normalized to the range [0,1].
static Color	optimizeContrastColor(Color color, Color background, int minimumContrastPercent)
static Color	optimizeContrastColorNoAlpha(Color color, Color background, int minimumContrastPercent) This is an experimental new contrast optimization strategy.
static Color	optimizeForegroundContrast(Color fg, Color bg) Optimize the contrast of the foreground color against the background by inverting it, if inversion leads to a higher contrast.
static Color	parseColor(String colorString)
static float[]	toHSL(Color c) Convert the given color to the HSB (sometimes called HSL) color model.
static String	toHtml(Color c) Convert the given RGB(A) color into an HTML color code of the Form #[6 or 8 hex digits].

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

alpha

public static Color alpha(Color c,
                          int alpha)

Create a new color identical to the given one, but having its alpha value replaced with the given one.

Parameters:

c -

alpha -

Returns:

the color with alpha applied

alpha

public static Color alpha(Color c,
                          float alpha)

Create a new color identical to the given one, but having its alpha value replaced with the given one.

Parameters:

c -

alpha -

Returns:

the color with alpha applied

alphaComposite

public static Color alphaComposite(Color fg,
                                   Color bg)

Composite two colors using alpha compositing.

Parameters:

fg - the foreground color

bg - the background color

Returns:

the composited color

luminance

public static float luminance(Color c)

Return the color's luminance normalized to the range [0,1].

Parameters:

c -

Returns:

the color's luminance

luminanceContrast

public static float luminanceContrast(Color c1,
                                      Color c2)

Return luminance contrast between the two colors normalized to the range [0,1].

Parameters:

c1 - first color

c2 - second color

Returns:

the luminance contrast

invert

public static Color invert(Color c)

Create a new color which is the inverse of the given one.

Parameters:

c -

optimizeForegroundContrast

public static Color optimizeForegroundContrast(Color fg,
                                               Color bg)

Optimize the contrast of the foreground color against the background by inverting it, if inversion leads to a higher contrast. Contrast is determined by looking at the color's luminance instead of by looking at individual channels.

Parameters:

fg - the foreground color

bg - the background color

Returns:

the optimized color

optimizeContrastColorNoAlpha

public static Color optimizeContrastColorNoAlpha(Color color,
                                                 Color background,
                                                 int minimumContrastPercent)

This is an experimental new contrast optimization strategy. Use at your own risk.

Parameters:

color -

background -

minimumContrastPercent -

Returns:

the optimized color

optimizeContrastColor

public static Color optimizeContrastColor(Color color,
                                          Color background,
                                          int minimumContrastPercent)

toHSL

public static float[] toHSL(Color c)

Convert the given color to the HSB (sometimes called HSL) color model. The returned values are normalized to the range [0,1].

Parameters:

c -

fromHSB

public static Color fromHSB(float[] hsl)

Convert the given color in the HSB (sometimes called HSL) color model into a Color in the color space sRGB. The given values must be normalized to the range [0,1].

Parameters:

hsl - the HSL components

fromHSB

public static Color fromHSB(float h,
                            float s,
                            float b)

Convert the given color in the HSB (sometimes called HSL) color model into a Color in the color space sRGB. The given values must be normalized to the range [0,1].

Parameters:

h - hue

s - saturation

b - brightness

parseColor

public static Color parseColor(String colorString)

toHtml

public static String toHtml(Color c)

Convert the given RGB(A) color into an HTML color code of the Form #[6 or 8 hex digits]. The conversion will automatically include the alpha channel (8 hex digits) or not (6 digits) depending on whether the color has transparency ( Color.getTransparency()).

Parameters:

c - the color

Returns:

the HTML color code