223 lines · cpp
1//===-- xray-graph.cpp: XRay Function Call Graph Renderer -----------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// A class to get a color from a specified gradient.10//11//===----------------------------------------------------------------------===//12 13#include "xray-color-helper.h"14#include "llvm/Support/FormatVariadic.h"15#include "llvm/Support/raw_ostream.h"16#include <cmath>17 18using namespace llvm;19using namespace xray;20 21// Sequential ColorMaps, which are used to represent information22// from some minimum to some maximum.23 24const std::tuple<uint8_t, uint8_t, uint8_t> SequentialMaps[][9] = {25 {// The greys color scheme from http://colorbrewer2.org/26 std::make_tuple(255, 255, 255), std::make_tuple(240, 240, 240),27 std::make_tuple(217, 217, 217), std::make_tuple(189, 189, 189),28 std::make_tuple(150, 150, 150), std::make_tuple(115, 115, 115),29 std::make_tuple(82, 82, 82), std::make_tuple(37, 37, 37),30 std::make_tuple(0, 0, 0)},31 {// The OrRd color scheme from http://colorbrewer2.org/32 std::make_tuple(255, 247, 236), std::make_tuple(254, 232, 200),33 std::make_tuple(253, 212, 158), std::make_tuple(253, 187, 132),34 std::make_tuple(252, 141, 89), std::make_tuple(239, 101, 72),35 std::make_tuple(215, 48, 31), std::make_tuple(179, 0, 0),36 std::make_tuple(127, 0, 0)},37 {// The PuBu color scheme from http://colorbrewer2.org/38 std::make_tuple(255, 247, 251), std::make_tuple(236, 231, 242),39 std::make_tuple(208, 209, 230), std::make_tuple(166, 189, 219),40 std::make_tuple(116, 169, 207), std::make_tuple(54, 144, 192),41 std::make_tuple(5, 112, 176), std::make_tuple(4, 90, 141),42 std::make_tuple(2, 56, 88)}};43 44// Sequential Maps extend the last colors given out of range inputs.45const std::tuple<uint8_t, uint8_t, uint8_t> SequentialBounds[][2] = {46 {// The Bounds for the greys color scheme47 std::make_tuple(255, 255, 255), std::make_tuple(0, 0, 0)},48 {// The Bounds for the OrRd color Scheme49 std::make_tuple(255, 247, 236), std::make_tuple(127, 0, 0)},50 {// The Bounds for the PuBu color Scheme51 std::make_tuple(255, 247, 251), std::make_tuple(2, 56, 88)}};52 53ColorHelper::ColorHelper(ColorHelper::SequentialScheme S)54 : MinIn(0.0), MaxIn(1.0), ColorMap(SequentialMaps[static_cast<int>(S)]),55 BoundMap(SequentialBounds[static_cast<int>(S)]) {}56 57// Diverging ColorMaps, which are used to represent information58// representing differenes, or a range that goes from negative to positive.59// These take an input in the range [-1,1].60 61const std::tuple<uint8_t, uint8_t, uint8_t> DivergingCoeffs[][11] = {62 {// The PiYG color scheme from http://colorbrewer2.org/63 std::make_tuple(142, 1, 82), std::make_tuple(197, 27, 125),64 std::make_tuple(222, 119, 174), std::make_tuple(241, 182, 218),65 std::make_tuple(253, 224, 239), std::make_tuple(247, 247, 247),66 std::make_tuple(230, 245, 208), std::make_tuple(184, 225, 134),67 std::make_tuple(127, 188, 65), std::make_tuple(77, 146, 33),68 std::make_tuple(39, 100, 25)}};69 70// Diverging maps use out of bounds ranges to show missing data. Missing Right71// Being below min, and missing left being above max.72const std::tuple<uint8_t, uint8_t, uint8_t> DivergingBounds[][2] = {73 {// The PiYG color scheme has green and red for missing right and left74 // respectively.75 std::make_tuple(255, 0, 0), std::make_tuple(0, 255, 0)}};76 77ColorHelper::ColorHelper(ColorHelper::DivergingScheme S)78 : MinIn(-1.0), MaxIn(1.0), ColorMap(DivergingCoeffs[static_cast<int>(S)]),79 BoundMap(DivergingBounds[static_cast<int>(S)]) {}80 81// Takes a tuple of uint8_ts representing a color in RGB and converts them to82// HSV represented by a tuple of doubles83static std::tuple<double, double, double>84convertToHSV(const std::tuple<uint8_t, uint8_t, uint8_t> &Color) {85 double Scaled[3] = {std::get<0>(Color) / 255.0, std::get<1>(Color) / 255.0,86 std::get<2>(Color) / 255.0};87 int Min = 0;88 int Max = 0;89 for (int i = 1; i < 3; ++i) {90 if (Scaled[i] < Scaled[Min])91 Min = i;92 if (Scaled[i] > Scaled[Max])93 Max = i;94 }95 96 double C = Scaled[Max] - Scaled[Min];97 98 double HPrime =99 (C == 0) ? 0 : (Scaled[(Max + 1) % 3] - Scaled[(Max + 2) % 3]) / C;100 HPrime = HPrime + 2.0 * Max;101 102 double H = (HPrime < 0) ? (HPrime + 6.0) * 60103 : HPrime * 60; // Scale to between 0 and 360104 double V = Scaled[Max];105 106 double S = (V == 0.0) ? 0.0 : C / V;107 108 return std::make_tuple(H, S, V);109}110 111// Takes a double precision number, clips it between 0 and 1 and then converts112// that to an integer between 0x00 and 0xFF with proxpper rounding.113static uint8_t unitIntervalTo8BitChar(double B) {114 double n = std::clamp(B, 0.0, 1.0);115 return static_cast<uint8_t>(255 * n + 0.5);116}117 118// Takes a typle of doubles representing a color in HSV and converts them to119// RGB represented as a tuple of uint8_ts120static std::tuple<uint8_t, uint8_t, uint8_t>121convertToRGB(const std::tuple<double, double, double> &Color) {122 const double &H = std::get<0>(Color);123 const double &S = std::get<1>(Color);124 const double &V = std::get<2>(Color);125 126 double C = V * S;127 128 double HPrime = H / 60;129 double X = C * (1 - std::abs(std::fmod(HPrime, 2.0) - 1));130 131 double RGB1[3];132 int HPrimeInt = static_cast<int>(HPrime);133 if (HPrimeInt % 2 == 0) {134 RGB1[(HPrimeInt / 2) % 3] = C;135 RGB1[(HPrimeInt / 2 + 1) % 3] = X;136 RGB1[(HPrimeInt / 2 + 2) % 3] = 0.0;137 } else {138 RGB1[(HPrimeInt / 2) % 3] = X;139 RGB1[(HPrimeInt / 2 + 1) % 3] = C;140 RGB1[(HPrimeInt / 2 + 2) % 3] = 0.0;141 }142 143 double Min = V - C;144 double RGB2[3] = {RGB1[0] + Min, RGB1[1] + Min, RGB1[2] + Min};145 146 return std::make_tuple(unitIntervalTo8BitChar(RGB2[0]),147 unitIntervalTo8BitChar(RGB2[1]),148 unitIntervalTo8BitChar(RGB2[2]));149}150 151// The Hue component of the HSV interpolation Routine152static double interpolateHue(double H0, double H1, double T) {153 double D = H1 - H0;154 if (H0 > H1) {155 std::swap(H0, H1);156 157 D = -D;158 T = 1 - T;159 }160 161 if (D <= 180) {162 return H0 + T * (H1 - H0);163 } else {164 H0 = H0 + 360;165 return std::fmod(H0 + T * (H1 - H0) + 720, 360);166 }167}168 169// Interpolates between two HSV Colors both represented as a tuple of doubles170// Returns an HSV Color represented as a tuple of doubles171static std::tuple<double, double, double>172interpolateHSV(const std::tuple<double, double, double> &C0,173 const std::tuple<double, double, double> &C1, double T) {174 double H = interpolateHue(std::get<0>(C0), std::get<0>(C1), T);175 double S = std::get<1>(C0) + T * (std::get<1>(C1) - std::get<1>(C0));176 double V = std::get<2>(C0) + T * (std::get<2>(C1) - std::get<2>(C0));177 return std::make_tuple(H, S, V);178}179 180// Get the Color as a tuple of uint8_ts181std::tuple<uint8_t, uint8_t, uint8_t>182ColorHelper::getColorTuple(double Point) const {183 assert(!ColorMap.empty() && "ColorMap must not be empty!");184 assert(!BoundMap.empty() && "BoundMap must not be empty!");185 186 if (Point < MinIn)187 return BoundMap[0];188 if (Point > MaxIn)189 return BoundMap[1];190 191 size_t MaxIndex = ColorMap.size() - 1;192 double IntervalWidth = MaxIn - MinIn;193 double OffsetP = Point - MinIn;194 double SectionWidth = IntervalWidth / static_cast<double>(MaxIndex);195 size_t SectionNo = std::floor(OffsetP / SectionWidth);196 double T = (OffsetP - SectionNo * SectionWidth) / SectionWidth;197 198 auto &RGBColor0 = ColorMap[SectionNo];199 auto &RGBColor1 = ColorMap[std::min(SectionNo + 1, MaxIndex)];200 201 auto HSVColor0 = convertToHSV(RGBColor0);202 auto HSVColor1 = convertToHSV(RGBColor1);203 204 auto InterpolatedHSVColor = interpolateHSV(HSVColor0, HSVColor1, T);205 return convertToRGB(InterpolatedHSVColor);206}207 208// A helper method to convert a color represented as tuple of uint8s to a hex209// string.210std::string211ColorHelper::getColorString(std::tuple<uint8_t, uint8_t, uint8_t> t) {212 return std::string(llvm::formatv("#{0:X-2}{1:X-2}{2:X-2}", std::get<0>(t),213 std::get<1>(t), std::get<2>(t)));214}215 216// Gets a color in a gradient given a number in the interval [0,1], it does this217// by evaluating a polynomial which maps [0, 1] -> [0, 1] for each of the R G218// and B values in the color. It then converts this [0,1] colors to a 24 bit219// color as a hex string.220std::string ColorHelper::getColorString(double Point) const {221 return getColorString(getColorTuple(Point));222}223