73
#ifndef RAINBOW_H
#define RAINBOW_H 1
#include <string>
#include <cstdio>
struct rgb {
int r, g, b;
void clamp() {
if (r > 255) r = 255; else if (r < 0) r = 0;
if (g > 255) g = 255; else if (g < 0) g = 0;
if (b > 255) b = 255; else if (b < 0) b = 0;
}
std::string str(char sep = ';') {
clamp();
return std::to_string((int)r) + sep + std::to_string((int)g) + sep + std::to_string((int)b);
}
void set(int rr, int gg, int bb) {r = rr;g = gg;b = bb; clamp();}
void set(rgb c) {r = c.r;g = c.g;b = c.b; clamp();}
void print(std::string s) {printf("\033[38;2;%sm%s\033[0m", str().c_str(), s.c_str());}
double operator[](int i) {
switch (i%3) {
case 0: return r;
case 1: return g;
case 2: return b;
}
return 0;
}
void indexAdd(int i, int v) {
switch (i%3) {
case 0: r += v; break;
case 1: g += v; break;
case 2: b += v; break;
}
clamp();
}
};
struct rainbow {
rgb c;
int s = 0; // step
void init(int len = 15) {
if (len <= 0) len = 15;
c.set(255, 0, 0);
s = 5.0*255.0 / len;
}
void next() {
if (s == 0) return;
for (int i = 0; i < 3; i++) {
if ((c[i+1]==0||c[i+1]==255)&&(c[i+2]==0||c[i+2]==255)) {
if (c[i+1]==0&&c[i+2]==255) c.indexAdd(i, s);
else if (c[i+1]==255&&c[i+2]==0) c.indexAdd(i, -s);
}
}
}
void print(std::string s) {c.print(s);}
void print2d(std::string s, int len = 30) {
rainbow r;
r.init(len);
r.c.set(c);
for (int i = 0; i < s.length(); i++) {
r.print(s.substr(i, 1));
r.next();
}
}
};
#endif