use HCL color space (Rec.2020 for luma) instead of HSV

cmake/ConkyBuildOptions.cmake

@@ -267,8 +267,6 @@ option(BUILD_PULSEAUDIO
 option(BUILD_INTEL_BACKLIGHT
        "Enable support for Intel backlight" false)
 
-option(BUILD_HSV_GRADIENT "Enable gradient in HSV colour space" true)
-
 message(STATUS "CMAKE_C_FLAGS: " ${CMAKE_C_FLAGS})
 message(STATUS "CMAKE_CXX_FLAGS: " ${CMAKE_CXX_FLAGS})
 

doc/config_settings.yaml

@@ -148,7 +148,9 @@ values:
       Substitute N by a number between 0 and 9 inclusive. Use the same
       format as a font variable.
   - name: forced_redraw
-    desc: Boolean value, if true, Conky will redraw everything when you switch the workspace. This may cause delays/flickering on some WMs.
+    desc: |-
+      Boolean value, if true, Conky will redraw everything when you switch the
+      workspace. This may cause delays/flickering on some WMs.
   - name: format_human_readable
     desc: |-
       If enabled, values which are in bytes will be printed in
@@ -373,7 +375,8 @@ values:
     desc: |-
       If own_window_transparent no, set a specified background
       colour. Takes either a hex value (e.g. '#ffffff'),
-      a shorthand hex value (e.g. '#fff'), or a valid RGB name (see `/usr/lib/X11/rgb.txt`).
+      a shorthand hex value (e.g. '#fff'), or a valid RGB nam 
+      (see `/usr/lib/X11/rgb.txt`).
     default: black
     args:
       - seconds
@@ -433,6 +436,13 @@ values:
     desc: Shows the time range covered by a graph.
   - name: show_graph_scale
     desc: Shows the maximum value in scaled graphs.
+  - name: graph_gradient_mode
+    desc: |-
+      Changes the color space used for interpolation. Arguments are hcl, hsv,
+      and rgb (default).
+    args:
+      - (rbg|hcl|hsv)
+    default: rgb
   - name: stippled_borders
     desc: Border stippling (dashing) in pixels.
   - name: temperature_unit

src/CMakeLists.txt

@@ -68,6 +68,8 @@ set(conky_sources
     exec.h
     fs.cc
     fs.h
+    gradient.cc
+    gradient.h
     mail.cc
     mail.h
     misc.cc
@@ -304,11 +306,6 @@ if(BUILD_INTEL_BACKLIGHT)
   set(optional_sources ${optional_sources} ${intel_backlight})
 endif(BUILD_INTEL_BACKLIGHT)
 
-if(BUILD_HSV_GRADIENT)
-  set(hsv_gradient hsv_gradient.cc hsv_gradient.h)
-  set(optional_sources ${optional_sources} ${hsv_gradient})
-endif(BUILD_HSV_GRADIENT)
-
 if(BUILD_TESTS)
   # Create a library strictly for testing
   add_library(conky_core ${conky_sources} ${optional_sources})

src/cmus.cc

@@ -99,12 +99,12 @@ void cmus_cb::work() {
 
       } else if (strncmp(line, "position ", 9) == 0) {
         cmus.curtime = line + 9;
-        cmus.timeleft =
-            strtol(cmus.totaltime.c_str(), nullptr, 10) -
-                strtol(cmus.curtime.c_str(), nullptr, 10);
+        cmus.timeleft = strtol(cmus.totaltime.c_str(), nullptr, 10) -
+                        strtol(cmus.curtime.c_str(), nullptr, 10);
         if (cmus.curtime.size() > 0) {
-          cmus.progress = static_cast<float>(strtol(cmus.curtime.c_str(), nullptr, 10)) /
-                          strtol(cmus.totaltime.c_str(), nullptr, 10);
+          cmus.progress =
+              static_cast<float>(strtol(cmus.curtime.c_str(), nullptr, 10)) /
+              strtol(cmus.totaltime.c_str(), nullptr, 10);
         } else {
           cmus.progress = 0;
         }
@@ -189,7 +189,8 @@ void print_cmus_totaltime(struct text_object *obj, char *p,
       lround(music_player_interval.get(*state) / active_update_interval()), 1l);
   const cmus_result &cmus =
       conky::register_cb<cmus_cb>(period)->get_result_copy();
-  format_seconds_short(p, p_max_size, strtol(cmus.totaltime.c_str(), nullptr, 10));
+  format_seconds_short(p, p_max_size,
+                       strtol(cmus.totaltime.c_str(), nullptr, 10));
 }
 
 void print_cmus_timeleft(struct text_object *obj, char *p,
@@ -209,7 +210,8 @@ void print_cmus_curtime(struct text_object *obj, char *p,
       lround(music_player_interval.get(*state) / active_update_interval()), 1l);
   const cmus_result &cmus =
       conky::register_cb<cmus_cb>(period)->get_result_copy();
-  format_seconds_short(p, p_max_size, strtol(cmus.curtime.c_str(), nullptr, 10));
+  format_seconds_short(p, p_max_size,
+                       strtol(cmus.curtime.c_str(), nullptr, 10));
 }
 
 #undef CMUS_PRINT_GENERATOR

src/colours.cc

@@ -83,69 +83,6 @@ unsigned int adjust_colours(unsigned int colour) {
   return colour;
 }
 
-/* this function returns the next colour between two colours for a gradient */
-std::unique_ptr<unsigned long[]> do_gradient(int width,
-                                             unsigned long first_colour,
-                                             unsigned long last_colour) {
-  int red1, green1, blue1;           // first colour
-  int red2, green2, blue2;           // last colour
-  int reddiff, greendiff, bluediff;  // difference
-  short redshift = (2 * colour_depth / 3 + colour_depth % 3);
-  short greenshift = (colour_depth / 3);
-
-  // Make sure the width is always at least 2
-  width = std::max(2, width);
-
-  std::unique_ptr<unsigned long[]> colours(new unsigned long[width]);
-
-  if (colour_depth == 0) { set_up_gradient(); }
-  red1 = (first_colour & redmask) >> redshift;
-  green1 = (first_colour & greenmask) >> greenshift;
-  blue1 = first_colour & bluemask;
-  red2 = (last_colour & redmask) >> redshift;
-  green2 = (last_colour & greenmask) >> greenshift;
-  blue2 = last_colour & bluemask;
-  reddiff = abs(red1 - red2);
-  greendiff = abs(green1 - green2);
-  bluediff = abs(blue1 - blue2);
-#ifdef HAVE_OPENMP
-#pragma omp parallel for schedule(dynamic, 10) shared(colours)
-#endif /* HAVE_OPENMP */
-  for (int i = 0; i < width; i++) {
-    int red3 = 0, green3 = 0, blue3 = 0;  // colour components
-
-    float factor = (static_cast<float>(i) / (width - 1));
-
-    /* the '+ 0.5' bit rounds our floats to ints properly */
-    if (red1 >= red2) {
-      red3 = -(factor * reddiff) - 0.5;
-    } else if (red1 < red2) {
-      red3 = factor * reddiff + 0.5;
-    }
-    if (green1 >= green2) {
-      green3 = -(factor * greendiff) - 0.5;
-    } else if (green1 < green2) {
-      green3 = factor * greendiff + 0.5;
-    }
-    if (blue1 >= blue2) {
-      blue3 = -(factor * bluediff) - 0.5;
-    } else if (blue1 < blue2) {
-      blue3 = factor * bluediff + 0.5;
-    }
-    red3 += red1;
-    green3 += green1;
-    blue3 += blue1;
-    if (red3 < 0) { red3 = 0; }
-    if (green3 < 0) { green3 = 0; }
-    if (blue3 < 0) { blue3 = 0; }
-    if (red3 > bluemask) { red3 = bluemask; }
-    if (green3 > bluemask) { green3 = bluemask; }
-    if (blue3 > bluemask) { blue3 = bluemask; }
-    colours[i] = (red3 << redshift) | (green3 << greenshift) | blue3;
-  }
-  return colours;
-}
-
 #ifdef BUILD_X11
 long get_x11_color(const char *name) {
   XColor color;

src/colours.h

@@ -33,7 +33,6 @@
 #include <string>
 
 unsigned int adjust_colours(unsigned int);
-std::unique_ptr<unsigned long[]> do_gradient(int, unsigned long, unsigned long);
 
 long get_x11_color(const std::string &colour);
 // XXX: when everyone uses C++ strings, remove this C version

src/common.cc

@@ -525,7 +525,8 @@ void print_cached(struct text_object *obj, char *p, unsigned int p_max_size) {
                  p_max_size);
 }
 
-void print_free_bufcache(struct text_object *obj, char *p, unsigned int p_max_size) {
+void print_free_bufcache(struct text_object *obj, char *p,
+                         unsigned int p_max_size) {
   human_readable(apply_base_multiplier(obj->data.s, info.free_bufcache), p,
                  p_max_size);
 }

src/conky.cc

@@ -133,9 +133,7 @@
 #include "openbsd.h"
 #endif /* __OpenBSD__ */
 
-#ifdef BUILD_HSV_GRADIENT
-#include "hsv_gradient.h"
-#endif /* BUILD_HSV_GRADIENT */
+#include "gradient.h"
 
 #ifdef BUILD_OLD_CONFIG
 #include "convertconf.h"
@@ -294,12 +292,19 @@ conky::range_config_setting<int> diskio_avg_samples("diskio_avg_samples", 1, 14,
                                                     2, true);
 
 #ifdef BUILD_GUI
-
+/* graph */
 conky::simple_config_setting<bool> show_graph_scale("show_graph_scale", false,
                                                     false);
 conky::simple_config_setting<bool> show_graph_range("show_graph_range", false,
                                                     false);
 
+enum gradient_state { RGB_GRADIENT = 0, HSV_GRADIENT, HCL_GRADIENT };
+template <>
+conky::lua_traits<gradient_state>::Map conky::lua_traits<gradient_state>::map =
+    {{"rgb", RGB_GRADIENT}, {"hsv", HSV_GRADIENT}, {"hcl", HCL_GRADIENT}};
+static conky::simple_config_setting<gradient_state> graph_gradient_mode(
+    "graph_gradient_mode", RGB_GRADIENT, false);
+
 /* Position on the screen */
 conky::simple_config_setting<int> gap_x("gap_x", 5, true);
 conky::simple_config_setting<int> gap_y("gap_y", 60, true);
@@ -401,6 +406,22 @@ int dpi_scale(int value) {
 #endif /* BUILD_GUI */
 }
 
+#ifdef BUILD_GUI
+conky::gradient_factory *create_gradient_factory(int width,
+                                                 unsigned long first_colour,
+                                                 unsigned long last_colour) {
+  switch (graph_gradient_mode.get(*state)) {
+    case RGB_GRADIENT:
+      return new conky::rgb_gradient_factory(width, first_colour, last_colour);
+    case HSV_GRADIENT:
+      return new conky::hsv_gradient_factory(width, first_colour, last_colour);
+    case HCL_GRADIENT:
+      return new conky::hcl_gradient_factory(width, first_colour, last_colour);
+  }
+  return nullptr;
+}
+#endif /* BUILD_GUI */
+
 /* formatted text to render on screen, generated in generate_text(),
  * drawn in draw_stuff() */
 
@@ -1294,13 +1315,10 @@ int draw_each_line_inner(char *s, int special_index, int last_special_applied) {
               std::unique_ptr<unsigned long[]> tmpcolour;
 
               if (current->last_colour != 0 || current->first_colour != 0) {
-#ifdef BUILD_HSV_GRADIENT
-                tmpcolour = do_hsv_gradient(w - 1, current->last_colour,
-                                            current->first_colour);
-#else  /* BUILD_HSV_GRADIENT */
-                tmpcolour = do_gradient(w - 1, current->last_colour,
-                                        current->first_colour);
-#endif /* BUILD_HSV_GRADIENT */
+                auto factory = create_gradient_factory(w, current->last_colour,
+                                                       current->first_colour);
+                tmpcolour = factory->create_gradient();
+                delete factory;
               }
               colour_idx = 0;
               for (i = w - 2; i > -1; i--) {

src/core.cc

@@ -434,7 +434,8 @@ struct text_object *construct_text_object(char *s, const char *arg, long line,
   END OBJ(freq, nullptr) get_cpu_count();
   if ((arg == nullptr) || strlen(arg) >= 3 ||
       strtol(&arg[0], nullptr, 10) == 0 ||
-      static_cast<unsigned int>(strtol(&arg[0], nullptr, 10)) > info.cpu_count) {
+      static_cast<unsigned int>(strtol(&arg[0], nullptr, 10)) >
+          info.cpu_count) {
     obj->data.i = 1;
     /* NORM_ERR("freq: Invalid CPU number or you don't have that many CPUs! "
       "Displaying the clock for CPU 1."); */
@@ -445,7 +446,8 @@ struct text_object *construct_text_object(char *s, const char *arg, long line,
   END OBJ(freq_g, nullptr) get_cpu_count();
   if ((arg == nullptr) || strlen(arg) >= 3 ||
       strtol(&arg[0], nullptr, 10) == 0 ||
-      static_cast<unsigned int>(strtol(&arg[0], nullptr, 10)) > info.cpu_count) {
+      static_cast<unsigned int>(strtol(&arg[0], nullptr, 10)) >
+          info.cpu_count) {
     obj->data.i = 1;
     /* NORM_ERR("freq_g: Invalid CPU number or you don't have that many "
       "CPUs! Displaying the clock for CPU 1."); */
@@ -457,7 +459,8 @@ struct text_object *construct_text_object(char *s, const char *arg, long line,
   END OBJ(cpugovernor, nullptr) get_cpu_count();
   if ((arg == nullptr) || strlen(arg) >= 3 ||
       strtol(&arg[0], nullptr, 10) == 0 ||
-      static_cast<unsigned int>(strtol(&arg[0], nullptr, 10)) > info.cpu_count) {
+      static_cast<unsigned int>(strtol(&arg[0], nullptr, 10)) >
+          info.cpu_count) {
     obj->data.i = 1;
     /* NORM_ERR("cpugovernor: Invalid CPU number or you don't have that "
       "many CPUs! Displaying the scaling governor for CPU 1."); */
@@ -484,7 +487,7 @@ struct text_object *construct_text_object(char *s, const char *arg, long line,
 #if defined(__linux__)
   END OBJ(voltage_mv, 0) get_cpu_count();
   if (!arg || strlen(arg) >= 3 || strtol(&arg[0], nullptr, 10) == 0 ||
-    (unsigned int)strtol(&arg[0], nullptr, 10) > info.cpu_count) {
+      (unsigned int)strtol(&arg[0], nullptr, 10) > info.cpu_count) {
     obj->data.i = 1;
     /* NORM_ERR("voltage_mv: Invalid CPU number or you don't have that many "
       "CPUs! Displaying voltage for CPU 1."); */
@@ -494,7 +497,7 @@ struct text_object *construct_text_object(char *s, const char *arg, long line,
   obj->callbacks.print = &print_voltage_mv;
   END OBJ(voltage_v, 0) get_cpu_count();
   if (!arg || strlen(arg) >= 3 || strtol(&arg[0], nullptr, 10) == 0 ||
-    (unsigned int)strtol(&arg[0], nullptr, 10) > info.cpu_count) {
+      (unsigned int)strtol(&arg[0], nullptr, 10) > info.cpu_count) {
     obj->data.i = 1;
     /* NORM_ERR("voltage_v: Invalid CPU number or you don't have that many "
       "CPUs! Displaying voltage for CPU 1."); */
@@ -1029,20 +1032,24 @@ struct text_object *construct_text_object(char *s, const char *arg, long line,
   END OBJ(fs_used, &update_fs_stats) init_fs(obj, arg);
   obj->callbacks.print = &print_fs_used;
 #ifdef BUILD_GUI
-  END OBJ(hr, nullptr) obj->data.l = arg != nullptr ? strtol(arg, nullptr, 10) : 1;
+  END OBJ(hr, nullptr) obj->data.l =
+      arg != nullptr ? strtol(arg, nullptr, 10) : 1;
   obj->callbacks.print = &new_hr;
 #endif /* BUILD_GUI */
   END OBJ(nameserver, &update_dns_data) parse_nameserver_arg(obj, arg);
   obj->callbacks.print = &print_nameserver;
   obj->callbacks.free = &free_dns_data;
-  END OBJ(offset, nullptr) obj->data.l = arg != nullptr ? strtol(arg, nullptr, 10) : 1;
+  END OBJ(offset, nullptr) obj->data.l =
+      arg != nullptr ? strtol(arg, nullptr, 10) : 1;
   obj->callbacks.print = &new_offset;
-  END OBJ(voffset, nullptr) obj->data.l = arg != nullptr ? strtol(arg, nullptr, 10) : 1;
+  END OBJ(voffset, nullptr) obj->data.l =
+      arg != nullptr ? strtol(arg, nullptr, 10) : 1;
   obj->callbacks.print = &new_voffset;
   END OBJ(save_coordinates, nullptr) obj->data.l =
       arg != nullptr ? strtol(arg, nullptr, 10) : 0;
   obj->callbacks.print = &new_save_coordinates;
-  END OBJ_ARG(goto, nullptr, "goto needs arguments") obj->data.l = strtol(arg, nullptr, 10);
+  END OBJ_ARG(goto, nullptr, "goto needs arguments") obj->data.l =
+      strtol(arg, nullptr, 10);
   obj->callbacks.print = &new_goto;
 #ifdef BUILD_GUI
   END OBJ(tab, nullptr) scan_tab(obj, arg);
@@ -1505,17 +1512,20 @@ struct text_object *construct_text_object(char *s, const char *arg, long line,
       parse_net_stat_arg(obj, arg, free_at_crash);
   obj->callbacks.print = &print_totalup;
   END OBJ(updates, nullptr) obj->callbacks.print = &print_updates;
-  END OBJ_IF(if_updatenr, nullptr) obj->data.i = arg != nullptr ? strtol(arg, nullptr, 10) : 0;
+  END OBJ_IF(if_updatenr, nullptr) obj->data.i =
+      arg != nullptr ? strtol(arg, nullptr, 10) : 0;
   if (obj->data.i == 0) {
     CRIT_ERR(obj, free_at_crash,
              "if_updatenr needs a number above 0 as argument");
   }
   set_updatereset(obj->data.i > get_updatereset() ? obj->data.i
                                                   : get_updatereset());
   obj->callbacks.iftest = &updatenr_iftest;
-  END OBJ(alignr, nullptr) obj->data.l = arg != nullptr ? strtol(arg, nullptr, 10) : 1;
+  END OBJ(alignr, nullptr) obj->data.l =
+      arg != nullptr ? strtol(arg, nullptr, 10) : 1;
   obj->callbacks.print = &new_alignr;
-  END OBJ(alignc, nullptr) obj->data.l = arg != nullptr ? strtol(arg, nullptr, 10) : 0;
+  END OBJ(alignc, nullptr) obj->data.l =
+      arg != nullptr ? strtol(arg, nullptr, 10) : 0;
   obj->callbacks.print = &new_alignc;
   END OBJ(upspeed, &update_net_stats)
       parse_net_stat_arg(obj, arg, free_at_crash);