java - 如何自动生成N "distinct"种颜色？

Question

我写了下面的两个方法来自动选择 N 种不同的颜色。它通过在 RGB 立方体上定义分段线性函数来工作。这样做的好处是，如果您想要的话，您还可以获得渐进比例，但是当 N 变大时，颜色会开始看起来相似。我也可以想象把RGB立方体均匀地分割成一个点阵，然后画点。有谁知道任何其他方法？我排除了定义一个列表然后循环遍历它的可能性。我还应该说，我通常不关心它们是否冲突或看起来不好看，它们只需要在视觉上截然不同即可。

public static List<Color> pick(int num) {
    List<Color> colors = new ArrayList<Color>();
    if (num < 2)
        return colors;
    float dx = 1.0f / (float) (num - 1);
    for (int i = 0; i < num; i++) {
        colors.add(get(i * dx));
    }
    return colors;
}

public static Color get(float x) {
    float r = 0.0f;
    float g = 0.0f;
    float b = 1.0f;
    if (x >= 0.0f && x < 0.2f) {
        x = x / 0.2f;
        r = 0.0f;
        g = x;
        b = 1.0f;
    } else if (x >= 0.2f && x < 0.4f) {
        x = (x - 0.2f) / 0.2f;
        r = 0.0f;
        g = 1.0f;
        b = 1.0f - x;
    } else if (x >= 0.4f && x < 0.6f) {
        x = (x - 0.4f) / 0.2f;
        r = x;
        g = 1.0f;
        b = 0.0f;
    } else if (x >= 0.6f && x < 0.8f) {
        x = (x - 0.6f) / 0.2f;
        r = 1.0f;
        g = 1.0f - x;
        b = 0.0f;
    } else if (x >= 0.8f && x <= 1.0f) {
        x = (x - 0.8f) / 0.2f;
        r = 1.0f;
        g = 0.0f;
        b = x;
    }
    return new Color(r, g, b);
}

Answer 1

这个问题出现在很多 SO 讨论中:

• Algorithm For Generating Unique Colors
• Generate unique colours
• Generate distinctly different RGB colors in graphs
• How to generate n different colors for any natural number n?

提出了不同的解决方案，但没有一个是最优的。幸运的是，科学来拯救

任意N

• Colour displays for categorical images (免费下载)
• A WEB SERVICE TO PERSONALISE MAP COLOURING (免费下载，网络服务解决方案应该在下个月可用)
• An Algorithm for the Selection of High-Contrast Color Sets (作者提供免费的 C++ 实现)
• High-contrast sets of colors (该问题的第一个算法)

最后 2 个将通过大多数大学图书馆/代理免费提供。

N 是有限的并且相对较小

在这种情况下，可以采用列表解决方案。该主题中的一篇非常有趣的文章是免费提供的:

• A Colour Alphabet and the Limits of Colour Coding

有几个颜色列表需要考虑:

• Boynton 列出的 11 种几乎不会混淆的颜色(可在上一节的第一篇论文中找到)
• 凯利的 22 种最大对比度颜色(在上面的论文中可用)

我也遇到了this麻省理工学院学生的调色板。最后，以下链接可能有助于在不同颜色系统/坐标之间进行转换(例如，文章中的某些颜色未在 RGB 中指定):

• http://chem8.org/uch/space-55036-do-blog-id-5333.html
• https://metacpan.org/pod/Color::Library::Dictionary::NBS_ISCC
• Color Theory: How to convert Munsell HVC to RGB/HSB/HSL

对于 Kelly 和 Boynton 的列表，我已经转换为 RGB(白色和黑色除外，这应该很明显)。一些 C# 代码:

public static ReadOnlyCollection<Color> KellysMaxContrastSet
{
    get { return _kellysMaxContrastSet.AsReadOnly(); }
}

private static readonly List<Color> _kellysMaxContrastSet = new List<Color>
{
    UIntToColor(0xFFFFB300), //Vivid Yellow
    UIntToColor(0xFF803E75), //Strong Purple
    UIntToColor(0xFFFF6800), //Vivid Orange
    UIntToColor(0xFFA6BDD7), //Very Light Blue
    UIntToColor(0xFFC10020), //Vivid Red
    UIntToColor(0xFFCEA262), //Grayish Yellow
    UIntToColor(0xFF817066), //Medium Gray

    //The following will not be good for people with defective color vision
    UIntToColor(0xFF007D34), //Vivid Green
    UIntToColor(0xFFF6768E), //Strong Purplish Pink
    UIntToColor(0xFF00538A), //Strong Blue
    UIntToColor(0xFFFF7A5C), //Strong Yellowish Pink
    UIntToColor(0xFF53377A), //Strong Violet
    UIntToColor(0xFFFF8E00), //Vivid Orange Yellow
    UIntToColor(0xFFB32851), //Strong Purplish Red
    UIntToColor(0xFFF4C800), //Vivid Greenish Yellow
    UIntToColor(0xFF7F180D), //Strong Reddish Brown
    UIntToColor(0xFF93AA00), //Vivid Yellowish Green
    UIntToColor(0xFF593315), //Deep Yellowish Brown
    UIntToColor(0xFFF13A13), //Vivid Reddish Orange
    UIntToColor(0xFF232C16), //Dark Olive Green
};

public static ReadOnlyCollection<Color> BoyntonOptimized
{
    get { return _boyntonOptimized.AsReadOnly(); }
}

private static readonly List<Color> _boyntonOptimized = new List<Color>
{
    Color.FromArgb(0, 0, 255),      //Blue
    Color.FromArgb(255, 0, 0),      //Red
    Color.FromArgb(0, 255, 0),      //Green
    Color.FromArgb(255, 255, 0),    //Yellow
    Color.FromArgb(255, 0, 255),    //Magenta
    Color.FromArgb(255, 128, 128),  //Pink
    Color.FromArgb(128, 128, 128),  //Gray
    Color.FromArgb(128, 0, 0),      //Brown
    Color.FromArgb(255, 128, 0),    //Orange
};

static public Color UIntToColor(uint color)
{
    var a = (byte)(color >> 24);
    var r = (byte)(color >> 16);
    var g = (byte)(color >> 8);
    var b = (byte)(color >> 0);
    return Color.FromArgb(a, r, g, b);
}

这里是十六进制和每 channel 8 位表示的 RGB 值:

kelly_colors_hex = [
    0xFFB300, # Vivid Yellow
    0x803E75, # Strong Purple
    0xFF6800, # Vivid Orange
    0xA6BDD7, # Very Light Blue
    0xC10020, # Vivid Red
    0xCEA262, # Grayish Yellow
    0x817066, # Medium Gray

    # The following don't work well for people with defective color vision
    0x007D34, # Vivid Green
    0xF6768E, # Strong Purplish Pink
    0x00538A, # Strong Blue
    0xFF7A5C, # Strong Yellowish Pink
    0x53377A, # Strong Violet
    0xFF8E00, # Vivid Orange Yellow
    0xB32851, # Strong Purplish Red
    0xF4C800, # Vivid Greenish Yellow
    0x7F180D, # Strong Reddish Brown
    0x93AA00, # Vivid Yellowish Green
    0x593315, # Deep Yellowish Brown
    0xF13A13, # Vivid Reddish Orange
    0x232C16, # Dark Olive Green
    ]

kelly_colors = dict(vivid_yellow=(255, 179, 0),
                    strong_purple=(128, 62, 117),
                    vivid_orange=(255, 104, 0),
                    very_light_blue=(166, 189, 215),
                    vivid_red=(193, 0, 32),
                    grayish_yellow=(206, 162, 98),
                    medium_gray=(129, 112, 102),

                    # these aren't good for people with defective color vision:
                    vivid_green=(0, 125, 52),
                    strong_purplish_pink=(246, 118, 142),
                    strong_blue=(0, 83, 138),
                    strong_yellowish_pink=(255, 122, 92),
                    strong_violet=(83, 55, 122),
                    vivid_orange_yellow=(255, 142, 0),
                    strong_purplish_red=(179, 40, 81),
                    vivid_greenish_yellow=(244, 200, 0),
                    strong_reddish_brown=(127, 24, 13),
                    vivid_yellowish_green=(147, 170, 0),
                    deep_yellowish_brown=(89, 51, 21),
                    vivid_reddish_orange=(241, 58, 19),
                    dark_olive_green=(35, 44, 22))

对于所有 Java 开发人员，这里是 JavaFX 颜色:

// Don't forget to import javafx.scene.paint.Color;

private static final Color[] KELLY_COLORS = {
    Color.web("0xFFB300"),    // Vivid Yellow
    Color.web("0x803E75"),    // Strong Purple
    Color.web("0xFF6800"),    // Vivid Orange
    Color.web("0xA6BDD7"),    // Very Light Blue
    Color.web("0xC10020"),    // Vivid Red
    Color.web("0xCEA262"),    // Grayish Yellow
    Color.web("0x817066"),    // Medium Gray

    Color.web("0x007D34"),    // Vivid Green
    Color.web("0xF6768E"),    // Strong Purplish Pink
    Color.web("0x00538A"),    // Strong Blue
    Color.web("0xFF7A5C"),    // Strong Yellowish Pink
    Color.web("0x53377A"),    // Strong Violet
    Color.web("0xFF8E00"),    // Vivid Orange Yellow
    Color.web("0xB32851"),    // Strong Purplish Red
    Color.web("0xF4C800"),    // Vivid Greenish Yellow
    Color.web("0x7F180D"),    // Strong Reddish Brown
    Color.web("0x93AA00"),    // Vivid Yellowish Green
    Color.web("0x593315"),    // Deep Yellowish Brown
    Color.web("0xF13A13"),    // Vivid Reddish Orange
    Color.web("0x232C16"),    // Dark Olive Green
};

以下是按照上面的顺序未排序的凯利色。

下面是按照色调排序的凯利色(注意有些黄色不是很反差)