polybar/include/utils/color.hpp

111 lines
2.8 KiB
C++

#pragma once
#include <iomanip>
#include "common.hpp"
#include "utils/string.hpp"
POLYBAR_NS
namespace color_util {
template <typename T = uint8_t>
T alpha_channel(const uint32_t value) {
uint8_t a = value >> 24;
if (std::is_same<T, uint8_t>::value)
return a << 8 / 0xff;
else if (std::is_same<T, uint16_t>::value)
return a << 8 | a << 8 / 0xff;
}
template <typename T = uint8_t>
T red_channel(const uint32_t value) {
uint8_t r = value >> 16;
if (std::is_same<T, uint8_t>::value)
return r << 8 / 0xff;
else if (std::is_same<T, uint16_t>::value)
return r << 8 | r << 8 / 0xff;
}
template <typename T = uint8_t>
T green_channel(const uint32_t value) {
uint8_t g = value >> 8;
if (std::is_same<T, uint8_t>::value)
return g << 8 / 0xff;
else if (std::is_same<T, uint16_t>::value)
return g << 8 | g << 8 / 0xff;
}
template <typename T = uint8_t>
T blue_channel(const uint32_t value) {
uint8_t b = value;
if (std::is_same<T, uint8_t>::value)
return b << 8 / 0xff;
else if (std::is_same<T, uint16_t>::value)
return b << 8 | b << 8 / 0xff;
}
template <typename T = uint32_t>
uint32_t premultiply_alpha(const T value) {
auto a = color_util::alpha_channel(value);
auto r = color_util::red_channel(value) * a / 255;
auto g = color_util::green_channel(value) * a / 255;
auto b = color_util::blue_channel(value) * a / 255;
return (a << 24) | (r << 16) | (g << 8) | b;
}
template <typename T>
string hex(uint32_t color) {
char s[12];
size_t len = 0;
uint8_t a = alpha_channel<T>(color);
uint8_t r = red_channel<T>(color);
uint8_t g = green_channel<T>(color);
uint8_t b = blue_channel<T>(color);
if (std::is_same<T, uint16_t>::value) {
len = snprintf(s, sizeof(s), "#%02x%02x%02x%02x", a, r, g, b);
} else if (std::is_same<T, uint8_t>::value) {
len = snprintf(s, sizeof(s), "#%02x%02x%02x", r, g, b);
}
return string{s, 0, len};
}
inline string parse_hex(string hex) {
if (hex[0] != '#')
hex.insert(0, 1, '#');
if (hex.length() == 4)
hex = {'#', hex[1], hex[1], hex[2], hex[2], hex[3], hex[3]};
if (hex.length() == 7)
hex = "#ff" + hex.substr(1);
if (hex.length() != 9)
return "";
return hex;
}
inline uint32_t parse(string hex, uint32_t fallback = 0) {
if ((hex = parse_hex(hex)).empty())
return fallback;
return strtoul(&hex[1], nullptr, 16);
}
inline string simplify_hex(string hex) {
// convert #ffrrggbb to #rrggbb
if (hex.length() == 9 && hex[1] == 'f' && hex[2] == 'f') {
hex.erase(1, 2);
}
// convert #rrggbb to #rgb
if (hex.length() == 7) {
if (hex[1] == hex[2] && hex[3] == hex[4] && hex[5] == hex[6]) {
hex = {'#', hex[1], hex[3], hex[5]};
}
}
return hex;
}
}
POLYBAR_NS_END