1 #include <petscsys.h> /*I "petscsys.h" I*/ 2 #include <petscdraw.h> 3 4 /* 5 Set up a color map, using uniform separation in hue space. 6 Map entries are Red, Green, Blue. 7 Values are "gamma" corrected. 8 */ 9 10 /* 11 Gamma is a monitor dependent value. The value here is an 12 approximate that gives somewhat better results than Gamma = 1. 13 */ 14 static PetscReal Gamma = 2.0; 15 16 PetscErrorCode PetscDrawUtilitySetGamma(PetscReal g) 17 { 18 PetscFunctionBegin; 19 Gamma = g; 20 PetscFunctionReturn(PETSC_SUCCESS); 21 } 22 23 static inline double PetscHlsHelper(double m1, double m2, double h) 24 { 25 while (h > 1.0) h -= 1.0; 26 while (h < 0.0) h += 1.0; 27 if (h < 1 / 6.0) return m1 + (m2 - m1) * h * 6; 28 if (h < 1 / 2.0) return m2; 29 if (h < 2 / 3.0) return m1 + (m2 - m1) * (2 / 3.0 - h) * 6; 30 return m1; 31 } 32 33 static inline void PetscHlsToRgb(double h, double l, double s, double *r, double *g, double *b) 34 { 35 if (s > 0.0) { 36 double m2 = l <= 0.5 ? l * (1.0 + s) : l + s - (l * s); 37 double m1 = 2 * l - m2; 38 *r = PetscHlsHelper(m1, m2, h + 1 / 3.); 39 *g = PetscHlsHelper(m1, m2, h); 40 *b = PetscHlsHelper(m1, m2, h - 1 / 3.); 41 } else { 42 /* ignore hue */ 43 *r = *g = *b = l; 44 } 45 } 46 47 static inline void PetscGammaCorrect(double *r, double *g, double *b) 48 { 49 PetscReal igamma = 1 / Gamma; 50 *r = (double)PetscPowReal((PetscReal)*r, igamma); 51 *g = (double)PetscPowReal((PetscReal)*g, igamma); 52 *b = (double)PetscPowReal((PetscReal)*b, igamma); 53 } 54 55 static PetscErrorCode PetscDrawCmap_Hue(int mapsize, unsigned char R[], unsigned char G[], unsigned char B[]) 56 { 57 int i; 58 double maxhue = 212.0 / 360, lightness = 0.5, saturation = 1.0; 59 60 PetscFunctionBegin; 61 for (i = 0; i < mapsize; i++) { 62 double hue = maxhue * (double)i / (mapsize - 1), r, g, b; 63 PetscHlsToRgb(hue, lightness, saturation, &r, &g, &b); 64 PetscGammaCorrect(&r, &g, &b); 65 R[i] = (unsigned char)(255 * PetscMin(r, 1.0)); 66 G[i] = (unsigned char)(255 * PetscMin(g, 1.0)); 67 B[i] = (unsigned char)(255 * PetscMin(b, 1.0)); 68 } 69 PetscFunctionReturn(PETSC_SUCCESS); 70 } 71 72 static PetscErrorCode PetscDrawCmap_Gray(int mapsize, unsigned char R[], unsigned char G[], unsigned char B[]) 73 { 74 int i; 75 PetscFunctionBegin; 76 for (i = 0; i < mapsize; i++) R[i] = G[i] = B[i] = (unsigned char)((255.0 * i) / (mapsize - 1)); 77 PetscFunctionReturn(PETSC_SUCCESS); 78 } 79 80 static PetscErrorCode PetscDrawCmap_Jet(int mapsize, unsigned char R[], unsigned char G[], unsigned char B[]) 81 { 82 int i; 83 const double knots[] = {0, 1 / 8., 3 / 8., 5 / 8., 7 / 8., 1}; 84 85 PetscFunctionBegin; 86 for (i = 0; i < mapsize; i++) { 87 double u = (double)i / (mapsize - 1); 88 double m, r = 0, g = 0, b = 0; 89 int k = 0; 90 while (k < 4 && u > knots[k + 1]) k++; 91 m = (u - knots[k]) / (knots[k + 1] - knots[k]); 92 switch (k) { 93 case 0: 94 r = 0; 95 g = 0; 96 b = (m + 1) / 2; 97 break; 98 case 1: 99 r = 0; 100 g = m; 101 b = 1; 102 break; 103 case 2: 104 r = m; 105 g = 1; 106 b = 1 - m; 107 break; 108 case 3: 109 r = 1; 110 g = 1 - m; 111 b = 0; 112 break; 113 case 4: 114 r = 1 - m / 2; 115 g = 0; 116 b = 0; 117 break; 118 } 119 R[i] = (unsigned char)(255 * PetscMin(r, 1.0)); 120 G[i] = (unsigned char)(255 * PetscMin(g, 1.0)); 121 B[i] = (unsigned char)(255 * PetscMin(b, 1.0)); 122 } 123 PetscFunctionReturn(PETSC_SUCCESS); 124 } 125 126 static PetscErrorCode PetscDrawCmap_Hot(int mapsize, unsigned char R[], unsigned char G[], unsigned char B[]) 127 { 128 int i; 129 const double knots[] = {0, 3 / 8., 3 / 4., 1}; 130 131 PetscFunctionBegin; 132 for (i = 0; i < mapsize; i++) { 133 double u = (double)i / (mapsize - 1); 134 double m, r = 0, g = 0, b = 0; 135 int k = 0; 136 while (k < 2 && u > knots[k + 1]) k++; 137 m = (u - knots[k]) / (knots[k + 1] - knots[k]); 138 switch (k) { 139 case 0: 140 r = m; 141 g = 0; 142 b = 0; 143 break; 144 case 1: 145 r = 1; 146 g = m; 147 b = 0; 148 break; 149 case 2: 150 r = 1; 151 g = 1; 152 b = m; 153 break; 154 } 155 R[i] = (unsigned char)(255 * PetscMin(r, 1.0)); 156 G[i] = (unsigned char)(255 * PetscMin(g, 1.0)); 157 B[i] = (unsigned char)(255 * PetscMin(b, 1.0)); 158 } 159 PetscFunctionReturn(PETSC_SUCCESS); 160 } 161 162 static PetscErrorCode PetscDrawCmap_Bone(int mapsize, unsigned char R[], unsigned char G[], unsigned char B[]) 163 { 164 int i; 165 PetscFunctionBegin; 166 (void)PetscDrawCmap_Hot(mapsize, R, G, B); 167 for (i = 0; i < mapsize; i++) { 168 double u = (double)i / (mapsize - 1); 169 double r = (7 * u + B[i] / 255.0) / 8; 170 double g = (7 * u + G[i] / 255.0) / 8; 171 double b = (7 * u + R[i] / 255.0) / 8; 172 R[i] = (unsigned char)(255 * PetscMin(r, 1.0)); 173 G[i] = (unsigned char)(255 * PetscMin(g, 1.0)); 174 B[i] = (unsigned char)(255 * PetscMin(b, 1.0)); 175 } 176 PetscFunctionReturn(PETSC_SUCCESS); 177 } 178 179 #include "../src/sys/classes/draw/utils/cmap/coolwarm.h" 180 #include "../src/sys/classes/draw/utils/cmap/parula.h" 181 #include "../src/sys/classes/draw/utils/cmap/viridis.h" 182 #include "../src/sys/classes/draw/utils/cmap/plasma.h" 183 #include "../src/sys/classes/draw/utils/cmap/inferno.h" 184 #include "../src/sys/classes/draw/utils/cmap/magma.h" 185 186 static struct { 187 const char *name; 188 const unsigned char (*data)[3]; 189 PetscErrorCode (*cmap)(int, unsigned char[], unsigned char[], unsigned char[]); 190 } PetscDrawCmapTable[] = { 191 {"hue", NULL, PetscDrawCmap_Hue }, /* varying hue with constant lightness and saturation */ 192 {"gray", NULL, PetscDrawCmap_Gray}, /* black to white with shades of gray */ 193 {"bone", NULL, PetscDrawCmap_Bone}, /* black to white with gray-blue shades */ 194 {"jet", NULL, PetscDrawCmap_Jet }, /* rainbow-like colormap from NCSA, University of Illinois */ 195 {"hot", NULL, PetscDrawCmap_Hot }, /* black-body radiation */ 196 {"coolwarm", PetscDrawCmap_coolwarm, NULL }, /* ParaView default (Cool To Warm with Diverging interpolation) */ 197 {"parula", PetscDrawCmap_parula, NULL }, /* MATLAB (default since R2014b) */ 198 {"viridis", PetscDrawCmap_viridis, NULL }, /* matplotlib 1.5 (default since 2.0) */ 199 {"plasma", PetscDrawCmap_plasma, NULL }, /* matplotlib 1.5 */ 200 {"inferno", PetscDrawCmap_inferno, NULL }, /* matplotlib 1.5 */ 201 {"magma", PetscDrawCmap_magma, NULL }, /* matplotlib 1.5 */ 202 }; 203 204 PetscErrorCode PetscDrawUtilitySetCmap(const char colormap[], int mapsize, unsigned char R[], unsigned char G[], unsigned char B[]) 205 { 206 int i, j; 207 const char *cmap_name_list[PETSC_STATIC_ARRAY_LENGTH(PetscDrawCmapTable)]; 208 PetscInt id = 0, count = (PetscInt)(sizeof(cmap_name_list) / sizeof(char *)); 209 PetscBool reverse = PETSC_FALSE, brighten = PETSC_FALSE; 210 PetscReal beta = 0; 211 212 PetscFunctionBegin; 213 for (i = 0; i < count; i++) cmap_name_list[i] = PetscDrawCmapTable[i].name; 214 if (colormap && colormap[0]) { 215 PetscBool match = PETSC_FALSE; 216 for (id = 0; !match && id < count; id++) PetscCall(PetscStrcasecmp(colormap, cmap_name_list[id], &match)); 217 PetscCheck(match, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Colormap '%s' not found", colormap); 218 } 219 PetscCall(PetscOptionsGetEList(NULL, NULL, "-draw_cmap", cmap_name_list, count, &id, NULL)); 220 PetscCall(PetscOptionsGetBool(NULL, NULL, "-draw_cmap_reverse", &reverse, NULL)); 221 PetscCall(PetscOptionsGetReal(NULL, NULL, "-draw_cmap_brighten", &beta, &brighten)); 222 PetscCheck(!brighten || (beta > (PetscReal)-1 && beta < (PetscReal) + 1), PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "brighten parameter %g must be in the range (-1,1)", (double)beta); 223 224 if (PetscDrawCmapTable[id].cmap) { 225 PetscCall(PetscDrawCmapTable[id].cmap(mapsize, R, G, B)); 226 } else { 227 const unsigned char(*rgb)[3] = PetscDrawCmapTable[id].data; 228 PetscCheck(mapsize == 256 - PETSC_DRAW_BASIC_COLORS, PETSC_COMM_SELF, PETSC_ERR_SUP, "Colormap '%s' with size %d not supported", cmap_name_list[id], mapsize); 229 for (i = 0; i < mapsize; i++) { 230 R[i] = rgb[i][0]; 231 G[i] = rgb[i][1]; 232 B[i] = rgb[i][2]; 233 } 234 } 235 236 if (reverse) { 237 i = 0; 238 j = mapsize - 1; 239 while (i < j) { 240 #define SWAP(a, i, j) \ 241 do { \ 242 unsigned char t = a[i]; \ 243 a[i] = a[j]; \ 244 a[j] = t; \ 245 } while (0) 246 SWAP(R, i, j); 247 SWAP(G, i, j); 248 SWAP(B, i, j); 249 #undef SWAP 250 i++; 251 j--; 252 } 253 } 254 255 if (brighten) { 256 PetscReal gamma = (beta > 0.0) ? (1 - beta) : (1 / (1 + beta)); 257 for (i = 0; i < mapsize; i++) { 258 PetscReal r = PetscPowReal((PetscReal)R[i] / 255, gamma); 259 PetscReal g = PetscPowReal((PetscReal)G[i] / 255, gamma); 260 PetscReal b = PetscPowReal((PetscReal)B[i] / 255, gamma); 261 R[i] = (unsigned char)(255 * PetscMin(r, (PetscReal)1.0)); 262 G[i] = (unsigned char)(255 * PetscMin(g, (PetscReal)1.0)); 263 B[i] = (unsigned char)(255 * PetscMin(b, (PetscReal)1.0)); 264 } 265 } 266 PetscFunctionReturn(PETSC_SUCCESS); 267 } 268