/********************************************************************
 * Color schemes from
 *  http://geography.uoregon.edu/datagraphics/color_scales.htm
 ********************************************************************/

// Green to Magenta, 16 steps
function rgb_gr2mg()
{
    r = [0.000, 0.000, 0.000, 0.000, 0.316, 0.526, 0.737, 1.000, 1.000, 1.000, 1.000, 1.000, 0.947, 0.737, 0.526, 0.316];
    g = [0.316, 0.526, 0.737, 0.947, 1.000, 1.000, 1.000, 1.000, 0.947, 0.737, 0.526, 0.316, 0.000, 0.000, 0.000, 0.000];
    b = [0.000, 0.000, 0.000, 0.000, 0.316, 0.526, 0.737, 1.000, 1.000, 1.000, 1.000, 1.000, 0.947, 0.737, 0.526, 0.316];
    return [r, g, b];
}

// Blue to Dark Red, 18 steps
function rgb_bl2dr()
{
    r = [0.142, 0.097, 0.160, 0.240, 0.340, 0.460, 0.600, 0.740, 0.920, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 0.970, 0.850, 0.650];
    g = [0.000, 0.112, 0.342, 0.531, 0.692, 0.829, 0.920, 0.978, 1.000, 1.000, 0.948, 0.840, 0.676, 0.472, 0.240, 0.155, 0.085, 0.000];
    b = [0.850, 0.970, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 0.920, 0.740, 0.600, 0.460, 0.340, 0.240, 0.210, 0.187, 0.130];
    return [r, g, b];
}

// Blue to Dark Orange, 18 steps
function rgb_bl2do()
{
    r = [0.000, 0.000, 0.000, 0.000, 0.200, 0.400, 0.600, 0.700, 0.800, 0.900, 1.000, 1.000, 1.000, 1.000, 1.000, 0.800, 0.600, 0.400];
    g = [0.400, 0.600, 0.800, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 0.900, 0.793, 0.680, 0.560, 0.433, 0.333, 0.240, 0.153];
    b = [0.400, 0.600, 0.800, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 0.800, 0.600, 0.400, 0.200, 0.000, 0.000, 0.000, 0.000];
    return [r, g, b];
}

function rgb_bl2do10()
{
    r = [0.000, 0.000, 0.200, 0.600, 0.800, 1.000, 1.000, 1.000, 0.800, 0.400];
    g = [0.400, 0.800, 1.000, 1.000, 1.000, 0.900, 0.680, 0.433, 0.333, 0.153];
    b = [0.400, 0.800, 1.000, 1.000, 1.000, 0.800, 0.400, 0.000, 0.000, 0.000];
    return [r, g, b];
}

// Blue to Green, 14 steps
function rgb_bl2gr()
{
    r = [0.000, 0.200, 0.400, 0.600, 0.700, 0.800, 0.900, 0.900, 0.800, 0.700, 0.600, 0.400, 0.200, 0.000];
    g = [0.000, 0.200, 0.400, 0.600, 0.700, 0.800, 0.900, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000];
    b = [1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 0.900, 0.800, 0.700, 0.600, 0.400, 0.200, 0.000];
    return [r, g, b];
}

// Brown to Blue, 12 steps
function rgb_br2bl()
{
    r = [0.200, 0.400, 0.600, 0.800, 0.850, 0.950, 0.800, 0.600, 0.400, 0.200, 0.000, 0.000];
    g = [0.100, 0.187, 0.379, 0.608, 0.688, 0.855, 0.993, 0.973, 0.940, 0.893, 0.667, 0.480];
    b = [0.000, 0.000, 0.210, 0.480, 0.595, 0.808, 1.000, 1.000, 1.000, 1.000, 0.800, 0.600];
    return [r, g, b];
}

// Blue to Orange Red, 14 steps
function rgb_bl2or()
{
    r = [0.030, 0.200, 0.350, 0.550, 0.750, 0.900, 0.970, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000];
    g = [0.353, 0.467, 0.567, 0.700, 0.833, 0.933, 0.980, 1.000, 1.000, 1.000, 0.800, 0.600, 0.400, 0.000];
    b = [1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 1.000, 0.800, 0.600, 0.000, 0.000, 0.000, 0.000, 0.000];
    return [r, g, b];
}

// Paired categorical scheme, 12-step
function rgb_paired()
{
    r = [1.000, 1.000, 1.000, 1.000, 0.700, 0.200, 0.650, 0.100, 0.800, 0.400, 1.000, 0.900];
    g = [0.750, 0.500, 1.000, 1.000, 1.000, 1.000, 0.930, 0.700, 0.750, 0.300, 0.600, 0.100];
    b = [0.500, 0.000, 0.600, 0.200, 0.550, 0.000, 1.000, 1.000, 1.000, 1.000, 0.750, 0.200];
    return [r, g, b];
}