Create a list of colors, blue to red, from 0% to 100%

Question

I want to create a list of colors, red-yellow-green-blue and mix with each other through a gap of 100. Does anyone have any experience with this?

Edit: Well, RGB really. Any language will do. I just need an algorithm.

Answer 1

A simple nested RGB loop will not generate your red-yellow-green-blue gradient. If this is really what you specifically want, then you should learn a little about the color wheel:

                    red
                     |
           magenta__ | __yellow
                    \|/
                  __/|\__
              blue   |   green
                     |
                    cyan

HSV, . , , . , :

// in javascript:
function cssColor (r, g, b) {
    return 'rgb('+r+','+g+','+b+')';
}

var colors = [];
// Start with solid red:
var r = 255;
var g = 0;
var b = 0;
// From red to yellow:
for (var g=0;g<=255;g++)  colors.push(cssColor(r,g,b));
// From yellow to green:
for (var r=255;r>=0;r--) colors.push(cssColor(r,g,b));
// From green to blue:
for (var b=0;b<=255;b++,g--)  colors.push(cssColor(r,g,b));

768 . , 100 :

var subColors = [];
for (var i=0;i<colors.length;i++) {
    if (i%8 == 0) subColors.push(colors[i]);
}

, , .

Answer 2

HSV ( - H = 0, S = V = 1, - H = 240, S = V = 1), RGB:

http://en.wikipedia.org/wiki/HSL_and_HSV#Converting_to_RGB

Answer 3

, 16 .

int[] colors;

for (int r = 0; i <= 255; i++)
{
    for (int g = 0; g <= 255; g++)
    {
        for (int b = 0; b <= 255; b++)
        {
            colors[] = rgb2int(r, g, b);
        }
    }
}

rgb2int(int red, int green, int blue)
{
    return (red << 16) + (green << 8) + blue;
}

Answer 4

3 . R 1 n g 1 n b 1 n

should give you 3 ^ n or so color -