identiconpp/src/identiconpp.hpp

148 lines
4.3 KiB
C++

/* This file is part of identiconpp.
* Copyright © 2018 tastytea <tastytea@tastytea.de>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 3.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <cstdint>
#include <string>
#include <vector>
#include <tuple>
#include <Magick++/Image.h>
using std::uint8_t;
using std::uint16_t;
using std::uint32_t;
using std::string;
using std::vector;
/*!
* @brief Base class for identiconpp.
*
* Use this class for all your identicons.
*/
class Identiconpp
{
public:
/*!
* @brief Return type for images.
*/
struct Image
{
uint8_t error;
Magick::Image data;
};
/*!
* @brief List of identicon types
*
* libravatar and sigil are synonymous.
*/
enum class identicon_type
{
simple,
libravatar,
sigil
};
/*!
* @brief Initialises an instance of Identiconpp.
*
* The instance can be used for creating identicons with differing
* image formats and sizes.
*
* @param rows Number of rows
* @param columns Number of columns
* @param background Background color, hexadecimal, rrggbbaa
* @param foreground vector of foreground colors
*/
explicit Identiconpp(const uint8_t rows, const uint8_t columns,
const uint32_t background = 0xffffffff,
const vector<uint32_t> &foreground = { 0x000000ff } );
/*!
* @brief Generates identicon from digest.
*
* @param digest The pre-computed digest
* @param type The type of identicon
* @param width The width of the image
* @param height The height of the image
*
* @return 0 and an image on success, 1 and an empty image on error.
*/
Image generate(const string &digest, identicon_type type,
const uint16_t width = 100, const uint16_t height = 100);
private:
const uint8_t _rows;
const uint8_t _columns;
const uint32_t _background;
const vector<uint32_t> _foreground;
/*!
* @brief Generate simple identicon.
*
* @param digest The pre-computed digest
* @param width The width of the image
* @param height The height of the image
*
* @return 0 and an image on success, 1 and an empty image on error.
*/
Image generate_simple(const string &digest,
const uint16_t width, const uint16_t height);
/*!
* @brief Generate libravatar-style / sigil identicon.
*
* @param digest The pre-computed digest
* @param width The width of the image
* @param height The height of the image
*
* @return 0 and an image on success, 1 and an empty image on error.
*/
Image generate_libravatar(const string &digest,
const uint16_t width, const uint16_t height);
/*!
* @brief Check if the digest contains enough entropy.
*
* Throws `std::invalid_argument` if not.
*
* @param digest The pre-computed digest
* @param type The type of identicon
*/
void check_entropy(const string &digest, identicon_type type);
/*!
* @brief Determines if the n-th bit of passed digest is 1 or 0.
*
* @param bit Bit to get
* @param digest The digest
*
* @return The bit.
*/
bool get_bit(const uint16_t bit, const string &digest);
/*!
* @brief Chooses a foreground color.
*
* Extracts the right bits from the digest and returns a color.
*
* @param firstbit The first bit of the digest to choose a color
* @param digest The digest
*
* @return A foreground color.
*/
Magick::Color get_color(const uint16_t firstbit, const string &digest);
};