Clase Random Para Colores

7/27/2019 Clase Random Para Colores

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9 Answers

activeoldestvotes

up vote38down voteaccepted

Use the random library:

import java.util.Random;

Then create a random generator:

Random rand = new Random();

As colours are separated into red green and blue, you can create a new random colour by creating

random primary colours:

// Java 'Color' class takes 3 floats, from 0 to 1.

float r = rand.nextFloat();

float g = rand.nextFloat();

float b = rand.nextFloat();

Then to finally create the colour, pass the primary colours into the constructor:

Color randomColor = new Color(r, g, b);


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--------------------------------------------------------------------------------

You can also create different random effects using this method, such as creating random colours

with more emphasis on certain colours ... pass in less green and blue to produce a "pinker"

random colour.

// Will produce a random colour with more red in it (usually "pink-ish")

float r = rand.nextFloat();

float g = rand.nextFloat(0.5);

float b = rand.nextFloat(0.5);

Or to ensure that only "light" colours are generated, you can generate colours that are always >

0.5 of each colour element:

// Will produce only bright / light colours:

float r = rand.nextFloat(0.5) + 0.5;

float g = rand.nextFloat(0.5) + 0.5;

float b = rand.nextFloat(0.5) + 0.5;

There are various other colour functions that can be used with the Color class, such as making the

colour brighter:

randomColor.brighter();

An overview of the Color class can be read here:

http://download.oracle.com/javase/6/docs/api/java/awt/Color.html

share|improve this answer


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edited Nov 22 '10 at 14:59

answered Nov 22 '10 at 14:28

Greg

6,89322754


4/16

up vote13down vote

If you want pleasing, pastel colors, it is best to use the HLS system.

final float hue = random.nextFloat();

// Saturation between 0.1 and 0.3

final float saturation = (random.nextInt(2000) + 1000) / 10000f;

final float luminance = 0.9f;

final Color color = Color.getHSBColor(hue, saturation, luminance);




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Sualeh Fatehi

1,039612

up vote4down vote

If you don't want it to look horrible I'd suggest defining a list of colours in an array and then using a

random number generator to pick one.

If you want a truly random colour you can just generate 3 random numbers between 0 and 255

and then use the Color(int,int,int) constructor to create a new Color instance.

Random randomGenerator = new Random();

int red = randomGenerator.nextInt(255);

int green = randomGenerator.nextInt(255);


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int blue = randomGenerator.nextInt(255);

Color randomColour = new Color(red,green,blue);



Rob Stevenson-Leggett

11.3k94392

And this way you can easily avoid points that are the same colour as the background. sje397 Nov

22 '10 at 14:29


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up vote4down vote

Copy paste this for bright pastel rainbow colors

int R = (int)(Math.random()*256);

int G = (int)(Math.random()*256);

int B= (int)(Math.random()*256);

Color color = new Color(R, G, B); //random color, but can be bright or dull

//to get rainbow, pastel colors

Random random = new Random();

final float hue = random.nextFloat();

final float saturation = 0.9f;//1.0 for brilliant, 0.0 for dull

final float luminance = 1.0f; //1.0 for brighter, 0.0 for black

color = Color.getHSBColor(hue, saturation, luminance);


answered Jan 5 '12 at 7:54


8/16

Komplot

711

Works great, thanks Komplot! Sahil Muthoo Jan 27 '12 at 12:04

up vote3down vote

I use this method:

function getRandomColor() {

var letters = '0123456789ABCDEF'.split('');

var color = '#';

for (var i = 0; i < 6; i++ ) {

color += letters[Math.round(Math.random() * 15)];

}

return color;

}


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You can see the code at work here.


edited Sep 22 '12 at 0:44

Sam

37.5k72346

answered Sep 21 '12 at 19:33

Brenden

511


10/16

1

can't you see he wants it in java..

Atharva Johri Apr 4 at 9:06

up vote1down vote

You can instantiate a color with three floats (r, g, b), each between 0.0 and 1.0:

http://download.oracle.com/javase/6/docs/api/java/awt/Color.html#Color(float,%20float,%20floa

t).

Using Java's Random class you can easily instantiate a new random color as such:

Random r = new Random();

Color randomColor = new Color(r.nextFloat(), r.nextFloat(), r.nextFloat());

I can't guarantee they'll all be pretty, but they'll be random =)



11/16


Jason Nichols

3,52821133

up vote1down vote

Sure. Just generate a color using random RGB values. Like:

public Color randomColor()

{

Random random=new Random(); // Probably really put this somewhere where it gets executed

only once

int red=random.nextInt(256);

int green=random.nextInt(256);


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int blue=random.nextInt(256);

return new Color(red, green, blue);

}

You might want to vary up the generation of the random numbers if you don't like the colors it

comes up with. I'd guess these will tend to be fairly dark.



Jay

12.8k22347

It's great. but, what can i do for creating lighter color? Elton.fd Nov 22 '10 at 14:44


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you can use the Color.brighter() method to make any generated color look like. Andrew Nov 22

'10 at 14:48

1

Sandra, to influence the brightness, make sure the random values are never very dark. 0 is darkest

and 255 is brightest, so just do a random.nextInt(128) + 128 for example to never get any colers

darker than half brightness. Stijn de Witt Nov 22 '10 at 14:49

yes, It works nice, thanks :) Elton.fd Nov 22 '10 at 15:03

@Stijn: Ditto. I might add that if you want more uniform brightness, you might make the 2nd value

depend on the 1st and the 3rd depending on the first two. Like say red=nextInt(255);

green=nextInt(255-red); etc. You could play with this sort of thing endlessly until you get the

results you want. Jay Nov 23 '10 at 17:22

show 2 more comments

up vote1down vote

You seem to want light random colors. Not sure what you mean exactly with light. But if you want

random 'rainbow colors', try this


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Random r = new Random();

Color c = Color.getHSBColor(r.nextFloat(),//random hue, color

1.0,//full saturation, 1.0 for 'colorful' colors, 0.0 for grey

1.0 //1.0 for bright, 0.0 for black

);

Search for HSB color model for more information.



Ishtar

4,699820


15/16

up vote0down vote

/** * */ package com.adil.util;

/** * The Class RandomColor. * * @author Adil OUIDAD */ public class RandomColor {

/**

* Constructeur par dfaut.

*/

public RandomColor() {

}

/**

* Gets the random color.

*

* @return the random color

*/

public static String getRandomColor() {

String[] letters = {"0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"};

String color = "#";

for (int i = 0; i < 6; i++ ) {

color += letters[(int) Math.round(Math.random() * 15)];


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}

return color;

}

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Clase Random Para Colores