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A header-only, single-file library for colormaps written in C++11.

Name	Sample
Parula
Heat
Hot
Jet
Gray
HSV

Reference:https://www.mathworks.com/help/matlab/ref/colormap.html

The HSV colormap is cyclic and is particularly useful for plotting angles or phases because the color transition from 1 to 0 is smooth. A phase wrap would thus not appear as a sharp edge.

Name	Sample
Magma
Inferno
Plasma
Viridis
Cividis

These colormaps are designed to be perceptually uniform (even in black-and-white printing) and friendly to colorblindness. Cividis is specially designed such that it enables as identical interpretation to both those without a CVD and those with red-green colorblindness as possible.

Magma, Inferno, Plasma, Viridis are released under CC0 by Nathaniel J. Smith, Stefan van der Walt, and (in the case of Viridis) Eric Firing:https://github.com/BIDS/colormap/blob/master/colormaps.py. Their python code is adapted for the use in C++11.

Cividis is released under CC0 by the authors of PLOS ONE paper (Jamie R. Nuñez, Christopher R. Anderton, Ryan S. Renslow):https://doi.org/10.1371/journal.pone.0199239. We incorporated the LUT into C++11.

Name	Sample
Github

This colormap is designed to mimic the color scheme used in GitHub contributions visualization.

Name	Sample
Turbo

Turbo is developed as an alternative to the Jet colormap by Anton Mikhailov (Google LLC). Seethe blog post for the details.The original lookup table is released under the Apache 2.0 license. We merged it and re-licensed the part under the MIT license for consistency.

Name	Sample
Cubehelix

Cubehelix is developed by Dr. Dave Green and is designed for astronomical intensity images. It shows a continuous increase in perceived intensity when shown in color or greyscale. This implementation uses Green's "default" scheme (start: 0.5, rotations: -1.5, hue: 1.0, gamma: 1.0). Seethe original publication for details.

tinycolormap does not have any dependencies except for C++11 standard library.

tinycolormap is a header-only library, so you do not need to compile it. You can use it by

• Adding the path to theinclude directory in the cloned tinycolormap repository to your project's include paths, or
• Copying the filetinycolormap.hpp to your project (note that tinycolormap consists of only that single file).

If your project is managed by Cmakehttps://cmake.org/,add_subdirectory orExternalProject_Add commands are useful as tinycolormap providesCMakeLists.txt for this purpose.

The core function of this library is

inline ColorGetColor(double x, ColormapType type);

wherex should be between0.0 and1.0 (otherwise, it will be cropped), andtype is the target colormap type likeViridis (default) andHeat.

Here is a working code:

#include<iostream>#include<tinycolormap.hpp>intmain(){// Define a target value. This value should be in [0, 1]; otherwise, it will be cropped to 0 or 1.constdouble value =0.5;// Get the mapped color. Here, Viridis is specified as the colormap.const tinycolormap::Color color =tinycolormap::GetColor(value, tinycolormap::ColormapType::Viridis);// Print the RGB values. Each value is in [0, 1].  std::cout <<"r =" << color.r() <<", g =" << color.g() <<", b =" << color.b() << std::endl;return0;}

tinycolormap is also capable of producing quantized colormaps (i.e. the ones that have visible boundaries between colors) based on the user specified number of levels. Below is the example of the quantized Parula colormap using 10 quantization levels:

Name	Sample
Parula

Note that the supported range for number of levels is[1, 255].

Here is an example code that uses colormap quantization:

intmain(){// Define a target value. This value should be in [0, 1]; otherwise, it will be cropped to 0 or 1.constdouble value =0.5;// Define number of levels for the colormap quantization. This value should be in [1, 255]; otherwise, it will be cropped to 1 or 255.constunsignedint num_levels =10;// Get the mapped color. Here, Parula is specified as the colormap.const tinycolormap::Color color =tinycolormap::GetQuantizedColor(value, num_levels, tinycolormap::ColormapType::Parula);// Print the RGB values. Each value is in [0, 1].  std::cout <<"r =" << color.r() <<", g =" << color.g() <<", b =" << color.b() << std::endl;return0;}

WhenTINYCOLORMAP_WITH_QT5 is defined before includingtinycolormap.hpp, for example,

#defineTINYCOLORMAP_WITH_QT5#include<tinycolormap.hpp>

(orTINYCOLORMAP_WITH_QT5 CMake option isON), this library offers an additional utility function:

const QColor color = tinycolormap::GetColor(x).ConvertToQColor();

WhenTINYCOLORMAP_WITH_EIGEN is defined before includingtinycolormap.hpp, for example,

#defineTINYCOLORMAP_WITH_EIGEN#include<tinycolormap.hpp>

(orTINYCOLORMAP_WITH_EIGEN CMake option isON), this library offers an additional utility function:

const Eigen::Vector3d color = tinycolormap::GetColor(x).ConvertToEigen();

When both Qt5 and Eigen are available, this library offers additional utility functions:

inline QImageCreateMatrixVisualization(const Eigen::MatrixXd& matrix);inlinevoidExportMatrixVisualization(const Eigen::MatrixXd& matrix,const std::string& path);

WhenTINYCOLORMAP_WITH_GLM is defined before includingtinycolormap.hpp, for example,

#defineTINYCOLORMAP_WITH_GLM#include<tinycolormap.hpp>

(orTINYCOLORMAP_WITH_GLM CMake option isON), this library offers an additional utility function:

const glm::vec3 color = tinycolormap::GetColor(x).ConvertToGLM();

This repository includes the following optional tools:

• PNG Exporter: This tool exports all the available colormaps as PNG images.

The optional tools are managed by CMakehttps://cmake.org/. They can be built by, for example,

mkdir buildcd buildcmake [PATH_TO_TINYCOLORMAP] -DTINYCOLORMAP_BUILD_TOOLS=ONmake

• riCOMhttps://github.com/ThFriedrich/riCOM_cpp
• OpenSiv3Dhttps://github.com/Siv3D/OpenSiv3D
• SLiMhttps://github.com/MesserLab/SLiM
• Neper: Polycrystal Generation and Meshinghttp://neper.info/
• Unblending (Pacific Graphics 2018)https://github.com/yuki-koyama/unblending
• OptiMo (CHI 2018)https://github.com/yuki-koyama/optimo
• Sequential Line Search (SIGGRAPH 2017)https://github.com/yuki-koyama/sequential-line-search
• SelPh (CHI 2016)https://github.com/yuki-koyama/selph
• VisOpt Slider (UIST 2014)https://github.com/yuki-koyama/visoptslider

The MIT License (except fortools/png-exporter/stb_image_write.h, which is released under public domain).

Pull requests are welcome.