light color map generation (c++)

gen_color.hpp

/// 다음의 코드를 수정하여 사용 https://gist.github.com/ialhashim/f52e1a4788e9feaf7d51
/// Color map based on work by Kenneth Moreland: http://www.sandia.gov/~kmorel/documents/ColorMaps/

#pragma once
#include <vector>
#include <cstdlib>
#include <ctime>

inline std::vector< std::vector<double> > makeColorMap(int num)
{
	std::vector<double> colorArray = 
	 {59,76,192,60,78,194,61,80,195,62,81,197,
		63,83,198,64,85,200,66,87,201,67,88,203,68,90,204,
		69,92,206,70,93,207,71,95,209,73,97,210,74,99,211,
		75,100,213,76,102,214,77,104,215,79,105,217,
		80,107,218,81,109,219,82,110,221,84,112,222,
		85,114,223,86,115,224,87,117,225,89,119,226,
		90,120,228,91,122,229,93,123,230,94,125,231,
		95,127,232,96,128,233,98,130,234,99,131,235,
		100,133,236,102,135,237,103,136,238,104,138,239,
		106,139,239,107,141,240,108,142,241,110,144,242,
		111,145,243,112,147,243,114,148,244,115,150,245,
		116,151,246,118,153,246,119,154,247,120,156,247,
		122,157,248,123,158,249,124,160,249,126,161,250,
		127,163,250,129,164,251,130,165,251,131,167,252,
		133,168,252,134,169,252,135,171,253,137,172,253,
		138,173,253,140,174,254,141,176,254,142,177,254,
		144,178,254,145,179,254,147,181,255,148,182,255,
		149,183,255,151,184,255,152,185,255,153,186,255,
		155,187,255,156,188,255,158,190,255,159,191,255,
		160,192,255,162,193,255,163,194,255,164,195,254,
		166,196,254,167,197,254,168,198,254,170,199,253,
		171,199,253,172,200,253,174,201,253,175,202,252,
		176,203,252,178,204,251,179,205,251,180,205,251,
		182,206,250,183,207,250,184,208,249,185,208,248,
		187,209,248,188,210,247,189,210,247,190,211,246,
		192,212,245,193,212,245,194,213,244,195,213,243,
		197,214,243,198,214,242,199,215,241,200,215,240,
		201,216,239,203,216,238,204,217,238,205,217,237,
		206,217,236,207,218,235,208,218,234,209,219,233,
		210,219,232,211,219,231,213,219,230,214,220,229,
		215,220,228,216,220,227,217,220,225,218,220,224,
		219,220,223,220,221,222,221,221,221,222,220,219,
		223,220,218,224,219,216,225,219,215,226,218,214,
		227,218,212,228,217,211,229,216,209,230,216,208,
		231,215,206,232,215,205,232,214,203,233,213,202,
		234,212,200,235,212,199,236,211,197,236,210,196,
		237,209,194,238,209,193,238,208,191,239,207,190,
		240,206,188,240,205,187,241,204,185,241,203,184,
		242,202,182,242,201,181,243,200,179,243,199,178,
		244,198,176,244,197,174,245,196,173,245,195,171,
		245,194,170,245,193,168,246,192,167,246,191,165,
		246,190,163,246,188,162,247,187,160,247,186,159,
		247,185,157,247,184,156,247,182,154,247,181,152,
		247,180,151,247,178,149,247,177,148,247,176,146,
		247,174,145,247,173,143,247,172,141,247,170,140,
		247,169,138,247,167,137,247,166,135,246,164,134,
		246,163,132,246,161,131,246,160,129,245,158,127,
		245,157,126,245,155,124,244,154,123,244,152,121,
		244,151,120,243,149,118,243,147,117,242,146,115,
		242,144,114,241,142,112,241,141,111,240,139,109,
		240,137,108,239,136,106,238,134,105,238,132,103,
		237,130,102,236,129,100,236,127,99,235,125,97,
		234,123,96,233,121,95,233,120,93,232,118,92,
		231,116,90,230,114,89,229,112,88,228,110,86,
		227,108,85,227,106,83,226,104,82,225,102,81,
		224,100,79,223,98,78,222,96,77,221,94,75,220,92,74,
		218,90,73,217,88,71,216,86,70,215,84,69,214,82,67,
		213,80,66,212,78,65,210,75,64,209,73,62,208,71,61,
		207,69,60,205,66,59,204,64,57,203,62,56,202,59,55,
		200,57,54,199,54,53,198,51,52,196,49,50,195,46,49,
		193,43,48,192,40,47,190,37,46,189,34,45,188,30,44,
		186,26,43,185,22,41,183,17,40,181,11,39,180,4,38}; 

    std::srand( (unsigned int) std::time(NULL) );
    
	std::vector< std::vector<double> > result;

    for (int i = 0; i < num; i++)
    {
        std::vector<double> color;
        int k = rand() % (colorArray.size() - 2);
        for(int j = 0; j < 3; j++) color.push_back( colorArray[k++] );
		result.push_back(color);
    }

	return result;
}

static inline std::vector<double> getColorFromMap(int i, const std::vector< std::vector<double> > & cmap){
	std::vector<double> c(3,0);
	int idx = i % cmap.size();
	c[0] = cmap[idx][0]; 
	c[1] = cmap[idx][1];
	c[2] = cmap[idx][2];
	return c;
}


/** Usage
 * 
 * cmap_ = makeColorMap(200);
 *  
 * std::vector<double> color = getColorFromMap(i, cmap_);
 * 
 * int r = (int)color[0];
 * int g = (int)color[1];
 * int b = (int)color[2];
 */