support husl perceptual colour values

tools/export.md

@@ -31,7 +31,7 @@ Such a configuration file must be supplied to the script as parameter e.g. execu
 The configuration file follows a simple organisational pattern for maximum versatility: all global icon parameters can be overridden by parameters specific to a certain icon id (except for sprites where only the colour can be changed). This is e.g. how re-colouring of icons works. An example of this pattern can be found in [osm-carto-png.yaml](https://github.com/gmgeo/osmic/blob/master/tools/config/osm-carto-png.yaml) where the global fill colour of `#734a08` is changed for the icon id `peak` to `#d08f55`.
 
 In the following all possible parameters are listed. All of them are optional.
-Colour values can be either specified as RGB value e.g. `rgb(255, 255, 255)` or `#ffffff` or as HSL value e.g. `hsl(20, 40%, 33%)`.
+Colour values can be either specified as RGB value e.g. `rgb(255, 255, 255)` or `#ffffff`, as HSL value e.g. `hsl(20, 40%, 33%)` or as perceptual HUSL value (http://www.husl-colors.org/) e.g. `husl(20, 40%, 33%)`.
 
 * `basedir` - specify the working directory, if not specified it defaults to the current working directory, relative and absolute paths are allowed, relative paths are evaluated against the current working directory
 
@@ -84,3 +84,6 @@ Colour values can be either specified as RGB value e.g. `rgb(255, 255, 255)` or
 
 * `font` - a list of configuration options for icon font generation
   * `output_basedir` - specify the output directory for the font files, if not specified it defaults to `./font`, can be either an absolute or relative path
+
+#### Dependencies
+* `husl` (`pip install husl`) if you want to specify HUSL colour values.

tools/export.py

@@ -364,7 +364,7 @@ def exportSprite(config, size_filter, num_icons):
         if 'background' in config['sprite']:
             sprite_background = parseColor(config['sprite']['background'])
             if sprite_background == None:
-                print('The specified background colour is invalid. Format it as HEX/RGB/HSL (e.g. #1a1a1a). Defaulting to none (transparent).')
+                print('The specified background colour is invalid. Format it as HEX/RGB/HSL/HUSL (e.g. #1a1a1a). Defaulting to none (transparent).')
 
         sprite_file_name = 'sprite'
         if 'filename' in config['sprite']:
@@ -529,31 +529,49 @@ def exportFont(config, size_filter):
     return
 
 
-# parse rgb, hex and hsl color definitions, return hex color or None on error
+# parse rgb, hex, hsl and husl (perceptual) color definitions, return hex color or None on error
+# husl needs husl library, load on demand
 def parseColor(color):
     parsed_color = None
-    if re.match('^#[0-9a-f]{6}$', color) != None:
-        parsed_color = color
-    rgb_match = re.search('^rgb\(([0-9]{1,3}),\s*([0-9]{1,3}),\s*([0-9]{1,3})\)$', color)
-    if rgb_match is not None:
-        try:
-            r = int(rgb_match.group(1))
-            g = int(rgb_match.group(2))
-            b = int(rgb_match.group(3))
-            parsed_color = '#'+("%x" % r)+("%x" % g)+("%x" % b)
-        except ValueError:
-            pass
-    else:
+    if color.startswith('#'):
+        if re.match('^#[0-9a-f]{6}$', color) != None:
+            parsed_color = color
+    elif color.startswith('rgb'):
+        rgb_match = re.search('^rgb\(([0-9]{1,3}),\s*([0-9]{1,3}),\s*([0-9]{1,3})\)$', color)
+        if rgb_match is not None:
+            try:
+                r = min(int(rgb_match.group(1)), 255)
+                g = min(int(rgb_match.group(2)), 255)
+                b = min(int(rgb_match.group(3)), 255)
+                parsed_color = '#'+("%x" % r)+("%x" % g)+("%x" % b)
+            except ValueError:
+                pass
+    elif color.startswith('hsl'):
         hsl_match = re.search('^hsl\(([0-9]{1,3}(\.[0-9]*)?),\s*([0-9]{1,3}(\.[0-9]*)?)\%,\s*([0-9]{1,3}(\.[0-9]*)?)\%\)$', color)
         if hsl_match is not None:
             try:
-                h = float(hsl_match.group(1)) / 365
-                s = float(hsl_match.group(3)) / 100
-                l = float(hsl_match.group(5)) / 100
+                h = min(float(hsl_match.group(1)) / 365, 1)
+                s = min(float(hsl_match.group(3)) / 100, 1)
+                l = min(float(hsl_match.group(5)) / 100, 1)
                 (r, g, b) = colorsys.hls_to_rgb(h, l, s)
                 parsed_color = '#'+("%x" % (r * 255))+("%x" % (g * 255))+("%x" % (b * 255))
             except ValueError:
                 pass
+    elif color.startswith('husl'):
+        husl_match = re.search('^husl\(([0-9]{1,3}(\.[0-9]*)?),\s*([0-9]{1,3}(\.[0-9]*)?)\%,\s*([0-9]{1,3}(\.[0-9]*)?)\%\)$', color)
+        if husl_match is not None:
+            try:
+                import husl
+                h = min(float(husl_match.group(1)), 360)
+                s = min(float(husl_match.group(3)), 100)
+                l = min(float(husl_match.group(5)), 100)
+                rgb = husl.husl_to_rgb(h, s, l)
+                parsed_color = husl.rgb_to_hex(rgb)
+            except ValueError:
+                pass
+            except ImportError:
+                print('HUSL colour definitions need the husl library. Please install it.')
+                pass
 
     return parsed_color
 
@@ -620,7 +638,7 @@ def modifySVG(config, icon_id, size, icon):
             shield_fill = parseColor(config['shield']['fill'])
             if shield_fill == None:
                 shield_fill = '#000000'
-                print('The specified shield fill is invalid. Format it as HEX/RGB/HSL (e.g. #1a1a1a). Defaulting to #000000 (black).')
+                print('The specified shield fill is invalid. Format it as HEX/RGB/HSL/HUSL (e.g. #1a1a1a). Defaulting to #000000 (black).')
         else:
             print('Shield fill not specified. Defaulting to #000000 (black).')
 
@@ -629,7 +647,7 @@ def modifySVG(config, icon_id, size, icon):
         if 'stroke_fill' in config['shield']:
             stroke_fill = parseColor(config['shield']['stroke_fill'])
             if stroke_fill == None:
-                print('The specified shield stroke fill is invalid. Format it as HEX/RGB/HSL (e.g. #1a1a1a).')
+                print('The specified shield stroke fill is invalid. Format it as HEX/RGB/HSL/HUSL (e.g. #1a1a1a).')
 
         stroke_width = None
         if 'stroke_width' in config['shield']:
@@ -674,7 +692,7 @@ def modifySVG(config, icon_id, size, icon):
             halo_fill = parseColor(config['halo']['fill'])
             if halo_fill == None:
                 halo_fill = '#ffffff'
-                print('The specified halo fill is invalid. Format it as HEX/RGB/HSL (e.g. #1a1a1a). Defaulting to #ffffff (white).')
+                print('The specified halo fill is invalid. Format it as HEX/RGB/HSL/HUSL (e.g. #1a1a1a). Defaulting to #ffffff (white).')
         else:
             print('Halo fill not specified. Defaulting to #ffffff (white).')
 
@@ -715,7 +733,7 @@ def modifySVG(config, icon_id, size, icon):
             path = xpEval("//def:path[@id='"+icon_id+"']")[0]
             path.attrib['style'] = re.sub('fill:#[0-9a-f]{6};?', 'fill:'+fill_color+';', path.attrib['style'])
         else:
-            print('The specified fill is invalid. Format it as HEX/RGB/HSL (e.g. #1a1a1a).')
+            print('The specified fill is invalid. Format it as HEX/RGB/HSL/HUSL (e.g. #1a1a1a).')
 
 
     # adjust document and canvas size, icon position