Add `minetest.colorspec_to_colorstring` (#10425)

5 files changed, 233 insertions, 225 deletions

diff --git a/doc/client_lua_api.txt b/doc/client_lua_api.txt
index c2c552440..1e8015f7b 100644
--- a/doc/client_lua_api.txt
+++ b/doc/client_lua_api.txt
@@ -651,6 +651,9 @@ Minetest namespace reference
 * `minetest.sha1(data, [raw])`: returns the sha1 hash of data
     * `data`: string of data to hash
     * `raw`: return raw bytes instead of hex digits, default: false
+* `minetest.colorspec_to_colorstring(colorspec)`: Converts a ColorSpec to a
+  ColorString. If the ColorSpec is invalid, returns `nil`.
+    * `colorspec`: The ColorSpec to convert
 * `minetest.get_csm_restrictions()`: returns a table of `Flags` indicating the
    restrictions applied to the current mod.
    * If a flag in this table is set to true, the feature is RESTRICTED.
@@ -1348,9 +1351,8 @@ The following functions provide escape sequences:
 
 Named colors are also supported and are equivalent to
 [CSS Color Module Level 4](http://dev.w3.org/csswg/css-color/#named-colors).
-To specify the value of the alpha channel, append `#AA` to the end of the color name
-(e.g. `colorname#08`). For named colors the hexadecimal string representing the alpha
-value must (always) be two hexadecimal digits.
+To specify the value of the alpha channel, append `#A` or `#AA` to the end of
+the color name (e.g. `colorname#08`).
 
 `Color`
 -------------
diff --git a/doc/lua_api.txt b/doc/lua_api.txt
index 5f72b8b2b..75cd6b7cc 100644
--- a/doc/lua_api.txt
+++ b/doc/lua_api.txt
@@ -3100,9 +3100,8 @@ Colors
 
 Named colors are also supported and are equivalent to
 [CSS Color Module Level 4](http://dev.w3.org/csswg/css-color/#named-colors).
-To specify the value of the alpha channel, append `#AA` to the end of the color
-name (e.g. `colorname#08`). For named colors the hexadecimal string
-representing the alpha value must (always) be two hexadecimal digits.
+To specify the value of the alpha channel, append `#A` or `#AA` to the end of
+the color name (e.g. `colorname#08`).
 
 `ColorSpec`
 -----------
@@ -4489,6 +4488,9 @@ Utilities
 * `minetest.sha1(data, [raw])`: returns the sha1 hash of data
     * `data`: string of data to hash
     * `raw`: return raw bytes instead of hex digits, default: false
+* `minetest.colorspec_to_colorstring(colorspec)`: Converts a ColorSpec to a
+  ColorString. If the ColorSpec is invalid, returns `nil`.
+    * `colorspec`: The ColorSpec to convert
 
 Logging
 -------
diff --git a/src/script/lua_api/l_util.cpp b/src/script/lua_api/l_util.cpp
index 203a0dd28..8de2d67c8 100644
--- a/src/script/lua_api/l_util.cpp
+++ b/src/script/lua_api/l_util.cpp
@@ -17,6 +17,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
+#include "irrlichttypes_extrabloated.h"
 #include "lua_api/l_util.h"
 #include "lua_api/l_internal.h"
 #include "lua_api/l_settings.h"
@@ -40,7 +41,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "util/hex.h"
 #include "util/sha1.h"
 #include <algorithm>
-
+#include <cstdio>
 
 // log([level,] text)
 // Writes a line to the logger.
@@ -479,6 +480,23 @@ int ModApiUtil::l_sha1(lua_State *L)
 	return 1;
 }
 
+// colorspec_to_colorstring(colorspec)
+int ModApiUtil::l_colorspec_to_colorstring(lua_State *L)
+{
+	NO_MAP_LOCK_REQUIRED;
+
+	video::SColor color(0);
+	if (read_color(L, 1, &color)) {
+		char colorstring[10];
+		snprintf(colorstring, 10, "#%02X%02X%02X%02X",
+			color.getRed(), color.getGreen(), color.getBlue(), color.getAlpha());
+		lua_pushstring(L, colorstring);
+		return 1;
+	}
+
+	return 0;
+}
+
 void ModApiUtil::Initialize(lua_State *L, int top)
 {
 	API_FCT(log);
@@ -513,6 +531,7 @@ void ModApiUtil::Initialize(lua_State *L, int top)
 
 	API_FCT(get_version);
 	API_FCT(sha1);
+	API_FCT(colorspec_to_colorstring);
 
 	LuaSettings::create(L, g_settings, g_settings_path);
 	lua_setfield(L, top, "settings");
@@ -537,6 +556,7 @@ void ModApiUtil::InitializeClient(lua_State *L, int top)
 
 	API_FCT(get_version);
 	API_FCT(sha1);
+	API_FCT(colorspec_to_colorstring);
 }
 
 void ModApiUtil::InitializeAsync(lua_State *L, int top)
@@ -564,8 +584,8 @@ void ModApiUtil::InitializeAsync(lua_State *L, int top)
 
 	API_FCT(get_version);
 	API_FCT(sha1);
+	API_FCT(colorspec_to_colorstring);
 
 	LuaSettings::create(L, g_settings, g_settings_path);
 	lua_setfield(L, top, "settings");
 }
-
diff --git a/src/script/lua_api/l_util.h b/src/script/lua_api/l_util.h
index dbdd62b99..6943a6afb 100644
--- a/src/script/lua_api/l_util.h
+++ b/src/script/lua_api/l_util.h
@@ -101,6 +101,9 @@ private:
 	// sha1(string, raw)
 	static int l_sha1(lua_State *L);
 
+	// colorspec_to_colorstring(colorspec)
+	static int l_colorspec_to_colorstring(lua_State *L);
+
 public:
 	static void Initialize(lua_State *L, int top);
 	static void InitializeAsync(lua_State *L, int top);
diff --git a/src/util/string.cpp b/src/util/string.cpp
index 611ad35cb..eec5ab4cd 100644
--- a/src/util/string.cpp
+++ b/src/util/string.cpp
@@ -30,7 +30,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include <array>
 #include <sstream>
 #include <iomanip>
-#include <map>
+#include <unordered_map>
 
 #ifndef _WIN32
 	#include <iconv.h>
@@ -44,10 +44,6 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 	#define BSD_ICONV_USED
 #endif
 
-static bool parseHexColorString(const std::string &value, video::SColor &color,
-		unsigned char default_alpha = 0xff);
-static bool parseNamedColorString(const std::string &value, video::SColor &color);
-
 #ifndef _WIN32
 
 static bool convert(const char *to, const char *from, char *outbuf,
@@ -324,29 +320,10 @@ u64 read_seed(const char *str)
 	return num;
 }
 
-bool parseColorString(const std::string &value, video::SColor &color, bool quiet,
-		unsigned char default_alpha)
-{
-	bool success;
-
-	if (value[0] == '#')
-		success = parseHexColorString(value, color, default_alpha);
-	else
-		success = parseNamedColorString(value, color);
-
-	if (!success && !quiet)
-		errorstream << "Invalid color: \"" << value << "\"" << std::endl;
-
-	return success;
-}
-
 static bool parseHexColorString(const std::string &value, video::SColor &color,
 		unsigned char default_alpha)
 {
-	unsigned char components[] = { 0x00, 0x00, 0x00, default_alpha }; // R,G,B,A
-
-	if (value[0] != '#')
-		return false;
+	u8 components[] = {0x00, 0x00, 0x00, default_alpha}; // R,G,B,A
 
 	size_t len = value.size();
 	bool short_form;
@@ -358,198 +335,182 @@ static bool parseHexColorString(const std::string &value, video::SColor &color,
 	else
 		return false;
 
-	bool success = true;
-
 	for (size_t pos = 1, cc = 0; pos < len; pos++, cc++) {
-		assert(cc < sizeof components / sizeof components[0]);
 		if (short_form) {
-			unsigned char d;
-			if (!hex_digit_decode(value[pos], d)) {
-				success = false;
-				break;
-			}
+			u8 d;
+			if (!hex_digit_decode(value[pos], d))
+				return false;
+
 			components[cc] = (d & 0xf) << 4 | (d & 0xf);
 		} else {
-			unsigned char d1, d2;
+			u8 d1, d2;
 			if (!hex_digit_decode(value[pos], d1) ||
-					!hex_digit_decode(value[pos+1], d2)) {
-				success = false;
-				break;
-			}
+					!hex_digit_decode(value[pos+1], d2))
+				return false;
+
 			components[cc] = (d1 & 0xf) << 4 | (d2 & 0xf);
-			pos++;	// skip the second digit -- it's already used
+			pos++; // skip the second digit -- it's already used
 		}
 	}
 
-	if (success) {
-		color.setRed(components[0]);
-		color.setGreen(components[1]);
-		color.setBlue(components[2]);
-		color.setAlpha(components[3]);
-	}
+	color.setRed(components[0]);
+	color.setGreen(components[1]);
+	color.setBlue(components[2]);
+	color.setAlpha(components[3]);
 
-	return success;
+	return true;
 }
 
-struct ColorContainer {
-	ColorContainer();
-	std::map<const std::string, u32> colors;
+const static std::unordered_map<std::string, u32> s_named_colors = {
+	{"aliceblue",            0xf0f8ff},
+	{"antiquewhite",         0xfaebd7},
+	{"aqua",                 0x00ffff},
+	{"aquamarine",           0x7fffd4},
+	{"azure",                0xf0ffff},
+	{"beige",                0xf5f5dc},
+	{"bisque",               0xffe4c4},
+	{"black",                00000000},
+	{"blanchedalmond",       0xffebcd},
+	{"blue",                 0x0000ff},
+	{"blueviolet",           0x8a2be2},
+	{"brown",                0xa52a2a},
+	{"burlywood",            0xdeb887},
+	{"cadetblue",            0x5f9ea0},
+	{"chartreuse",           0x7fff00},
+	{"chocolate",            0xd2691e},
+	{"coral",                0xff7f50},
+	{"cornflowerblue",       0x6495ed},
+	{"cornsilk",             0xfff8dc},
+	{"crimson",              0xdc143c},
+	{"cyan",                 0x00ffff},
+	{"darkblue",             0x00008b},
+	{"darkcyan",             0x008b8b},
+	{"darkgoldenrod",        0xb8860b},
+	{"darkgray",             0xa9a9a9},
+	{"darkgreen",            0x006400},
+	{"darkgrey",             0xa9a9a9},
+	{"darkkhaki",            0xbdb76b},
+	{"darkmagenta",          0x8b008b},
+	{"darkolivegreen",       0x556b2f},
+	{"darkorange",           0xff8c00},
+	{"darkorchid",           0x9932cc},
+	{"darkred",              0x8b0000},
+	{"darksalmon",           0xe9967a},
+	{"darkseagreen",         0x8fbc8f},
+	{"darkslateblue",        0x483d8b},
+	{"darkslategray",        0x2f4f4f},
+	{"darkslategrey",        0x2f4f4f},
+	{"darkturquoise",        0x00ced1},
+	{"darkviolet",           0x9400d3},
+	{"deeppink",             0xff1493},
+	{"deepskyblue",          0x00bfff},
+	{"dimgray",              0x696969},
+	{"dimgrey",              0x696969},
+	{"dodgerblue",           0x1e90ff},
+	{"firebrick",            0xb22222},
+	{"floralwhite",          0xfffaf0},
+	{"forestgreen",          0x228b22},
+	{"fuchsia",              0xff00ff},
+	{"gainsboro",            0xdcdcdc},
+	{"ghostwhite",           0xf8f8ff},
+	{"gold",                 0xffd700},
+	{"goldenrod",            0xdaa520},
+	{"gray",                 0x808080},
+	{"green",                0x008000},
+	{"greenyellow",          0xadff2f},
+	{"grey",                 0x808080},
+	{"honeydew",             0xf0fff0},
+	{"hotpink",              0xff69b4},
+	{"indianred",            0xcd5c5c},
+	{"indigo",               0x4b0082},
+	{"ivory",                0xfffff0},
+	{"khaki",                0xf0e68c},
+	{"lavender",             0xe6e6fa},
+	{"lavenderblush",        0xfff0f5},
+	{"lawngreen",            0x7cfc00},
+	{"lemonchiffon",         0xfffacd},
+	{"lightblue",            0xadd8e6},
+	{"lightcoral",           0xf08080},
+	{"lightcyan",            0xe0ffff},
+	{"lightgoldenrodyellow", 0xfafad2},
+	{"lightgray",            0xd3d3d3},
+	{"lightgreen",           0x90ee90},
+	{"lightgrey",            0xd3d3d3},
+	{"lightpink",            0xffb6c1},
+	{"lightsalmon",          0xffa07a},
+	{"lightseagreen",        0x20b2aa},
+	{"lightskyblue",         0x87cefa},
+	{"lightslategray",       0x778899},
+	{"lightslategrey",       0x778899},
+	{"lightsteelblue",       0xb0c4de},
+	{"lightyellow",          0xffffe0},
+	{"lime",                 0x00ff00},
+	{"limegreen",            0x32cd32},
+	{"linen",                0xfaf0e6},
+	{"magenta",              0xff00ff},
+	{"maroon",               0x800000},
+	{"mediumaquamarine",     0x66cdaa},
+	{"mediumblue",           0x0000cd},
+	{"mediumorchid",         0xba55d3},
+	{"mediumpurple",         0x9370db},
+	{"mediumseagreen",       0x3cb371},
+	{"mediumslateblue",      0x7b68ee},
+	{"mediumspringgreen",    0x00fa9a},
+	{"mediumturquoise",      0x48d1cc},
+	{"mediumvioletred",      0xc71585},
+	{"midnightblue",         0x191970},
+	{"mintcream",            0xf5fffa},
+	{"mistyrose",            0xffe4e1},
+	{"moccasin",             0xffe4b5},
+	{"navajowhite",          0xffdead},
+	{"navy",                 0x000080},
+	{"oldlace",              0xfdf5e6},
+	{"olive",                0x808000},
+	{"olivedrab",            0x6b8e23},
+	{"orange",               0xffa500},
+	{"orangered",            0xff4500},
+	{"orchid",               0xda70d6},
+	{"palegoldenrod",        0xeee8aa},
+	{"palegreen",            0x98fb98},
+	{"paleturquoise",        0xafeeee},
+	{"palevioletred",        0xdb7093},
+	{"papayawhip",           0xffefd5},
+	{"peachpuff",            0xffdab9},
+	{"peru",                 0xcd853f},
+	{"pink",                 0xffc0cb},
+	{"plum",                 0xdda0dd},
+	{"powderblue",           0xb0e0e6},
+	{"purple",               0x800080},
+	{"red",                  0xff0000},
+	{"rosybrown",            0xbc8f8f},
+	{"royalblue",            0x4169e1},
+	{"saddlebrown",          0x8b4513},
+	{"salmon",               0xfa8072},
+	{"sandybrown",           0xf4a460},
+	{"seagreen",             0x2e8b57},
+	{"seashell",             0xfff5ee},
+	{"sienna",               0xa0522d},
+	{"silver",               0xc0c0c0},
+	{"skyblue",              0x87ceeb},
+	{"slateblue",            0x6a5acd},
+	{"slategray",            0x708090},
+	{"slategrey",            0x708090},
+	{"snow",                 0xfffafa},
+	{"springgreen",          0x00ff7f},
+	{"steelblue",            0x4682b4},
+	{"tan",                  0xd2b48c},
+	{"teal",                 0x008080},
+	{"thistle",              0xd8bfd8},
+	{"tomato",               0xff6347},
+	{"turquoise",            0x40e0d0},
+	{"violet",               0xee82ee},
+	{"wheat",                0xf5deb3},
+	{"white",                0xffffff},
+	{"whitesmoke",           0xf5f5f5},
+	{"yellow",               0xffff00},
+	{"yellowgreen",          0x9acd32}
 };
 
-ColorContainer::ColorContainer()
-{
-	colors["aliceblue"]              = 0xf0f8ff;
-	colors["antiquewhite"]           = 0xfaebd7;
-	colors["aqua"]                   = 0x00ffff;
-	colors["aquamarine"]             = 0x7fffd4;
-	colors["azure"]                  = 0xf0ffff;
-	colors["beige"]                  = 0xf5f5dc;
-	colors["bisque"]                 = 0xffe4c4;
-	colors["black"]                  = 00000000;
-	colors["blanchedalmond"]         = 0xffebcd;
-	colors["blue"]                   = 0x0000ff;
-	colors["blueviolet"]             = 0x8a2be2;
-	colors["brown"]                  = 0xa52a2a;
-	colors["burlywood"]              = 0xdeb887;
-	colors["cadetblue"]              = 0x5f9ea0;
-	colors["chartreuse"]             = 0x7fff00;
-	colors["chocolate"]              = 0xd2691e;
-	colors["coral"]                  = 0xff7f50;
-	colors["cornflowerblue"]         = 0x6495ed;
-	colors["cornsilk"]               = 0xfff8dc;
-	colors["crimson"]                = 0xdc143c;
-	colors["cyan"]                   = 0x00ffff;
-	colors["darkblue"]               = 0x00008b;
-	colors["darkcyan"]               = 0x008b8b;
-	colors["darkgoldenrod"]          = 0xb8860b;
-	colors["darkgray"]               = 0xa9a9a9;
-	colors["darkgreen"]              = 0x006400;
-	colors["darkgrey"]               = 0xa9a9a9;
-	colors["darkkhaki"]              = 0xbdb76b;
-	colors["darkmagenta"]            = 0x8b008b;
-	colors["darkolivegreen"]         = 0x556b2f;
-	colors["darkorange"]             = 0xff8c00;
-	colors["darkorchid"]             = 0x9932cc;
-	colors["darkred"]                = 0x8b0000;
-	colors["darksalmon"]             = 0xe9967a;
-	colors["darkseagreen"]           = 0x8fbc8f;
-	colors["darkslateblue"]          = 0x483d8b;
-	colors["darkslategray"]          = 0x2f4f4f;
-	colors["darkslategrey"]          = 0x2f4f4f;
-	colors["darkturquoise"]          = 0x00ced1;
-	colors["darkviolet"]             = 0x9400d3;
-	colors["deeppink"]               = 0xff1493;
-	colors["deepskyblue"]            = 0x00bfff;
-	colors["dimgray"]                = 0x696969;
-	colors["dimgrey"]                = 0x696969;
-	colors["dodgerblue"]             = 0x1e90ff;
-	colors["firebrick"]              = 0xb22222;
-	colors["floralwhite"]            = 0xfffaf0;
-	colors["forestgreen"]            = 0x228b22;
-	colors["fuchsia"]                = 0xff00ff;
-	colors["gainsboro"]              = 0xdcdcdc;
-	colors["ghostwhite"]             = 0xf8f8ff;
-	colors["gold"]                   = 0xffd700;
-	colors["goldenrod"]              = 0xdaa520;
-	colors["gray"]                   = 0x808080;
-	colors["green"]                  = 0x008000;
-	colors["greenyellow"]            = 0xadff2f;
-	colors["grey"]                   = 0x808080;
-	colors["honeydew"]               = 0xf0fff0;
-	colors["hotpink"]                = 0xff69b4;
-	colors["indianred"]              = 0xcd5c5c;
-	colors["indigo"]                 = 0x4b0082;
-	colors["ivory"]                  = 0xfffff0;
-	colors["khaki"]                  = 0xf0e68c;
-	colors["lavender"]               = 0xe6e6fa;
-	colors["lavenderblush"]          = 0xfff0f5;
-	colors["lawngreen"]              = 0x7cfc00;
-	colors["lemonchiffon"]           = 0xfffacd;
-	colors["lightblue"]              = 0xadd8e6;
-	colors["lightcoral"]             = 0xf08080;
-	colors["lightcyan"]              = 0xe0ffff;
-	colors["lightgoldenrodyellow"]   = 0xfafad2;
-	colors["lightgray"]              = 0xd3d3d3;
-	colors["lightgreen"]             = 0x90ee90;
-	colors["lightgrey"]              = 0xd3d3d3;
-	colors["lightpink"]              = 0xffb6c1;
-	colors["lightsalmon"]            = 0xffa07a;
-	colors["lightseagreen"]          = 0x20b2aa;
-	colors["lightskyblue"]           = 0x87cefa;
-	colors["lightslategray"]         = 0x778899;
-	colors["lightslategrey"]         = 0x778899;
-	colors["lightsteelblue"]         = 0xb0c4de;
-	colors["lightyellow"]            = 0xffffe0;
-	colors["lime"]                   = 0x00ff00;
-	colors["limegreen"]              = 0x32cd32;
-	colors["linen"]                  = 0xfaf0e6;
-	colors["magenta"]                = 0xff00ff;
-	colors["maroon"]                 = 0x800000;
-	colors["mediumaquamarine"]       = 0x66cdaa;
-	colors["mediumblue"]             = 0x0000cd;
-	colors["mediumorchid"]           = 0xba55d3;
-	colors["mediumpurple"]           = 0x9370db;
-	colors["mediumseagreen"]         = 0x3cb371;
-	colors["mediumslateblue"]        = 0x7b68ee;
-	colors["mediumspringgreen"]      = 0x00fa9a;
-	colors["mediumturquoise"]        = 0x48d1cc;
-	colors["mediumvioletred"]        = 0xc71585;
-	colors["midnightblue"]           = 0x191970;
-	colors["mintcream"]              = 0xf5fffa;
-	colors["mistyrose"]              = 0xffe4e1;
-	colors["moccasin"]               = 0xffe4b5;
-	colors["navajowhite"]            = 0xffdead;
-	colors["navy"]                   = 0x000080;
-	colors["oldlace"]                = 0xfdf5e6;
-	colors["olive"]                  = 0x808000;
-	colors["olivedrab"]              = 0x6b8e23;
-	colors["orange"]                 = 0xffa500;
-	colors["orangered"]              = 0xff4500;
-	colors["orchid"]                 = 0xda70d6;
-	colors["palegoldenrod"]          = 0xeee8aa;
-	colors["palegreen"]              = 0x98fb98;
-	colors["paleturquoise"]          = 0xafeeee;
-	colors["palevioletred"]          = 0xdb7093;
-	colors["papayawhip"]             = 0xffefd5;
-	colors["peachpuff"]              = 0xffdab9;
-	colors["peru"]                   = 0xcd853f;
-	colors["pink"]                   = 0xffc0cb;
-	colors["plum"]                   = 0xdda0dd;
-	colors["powderblue"]             = 0xb0e0e6;
-	colors["purple"]                 = 0x800080;
-	colors["red"]                    = 0xff0000;
-	colors["rosybrown"]              = 0xbc8f8f;
-	colors["royalblue"]              = 0x4169e1;
-	colors["saddlebrown"]            = 0x8b4513;
-	colors["salmon"]                 = 0xfa8072;
-	colors["sandybrown"]             = 0xf4a460;
-	colors["seagreen"]               = 0x2e8b57;
-	colors["seashell"]               = 0xfff5ee;
-	colors["sienna"]                 = 0xa0522d;
-	colors["silver"]                 = 0xc0c0c0;
-	colors["skyblue"]                = 0x87ceeb;
-	colors["slateblue"]              = 0x6a5acd;
-	colors["slategray"]              = 0x708090;
-	colors["slategrey"]              = 0x708090;
-	colors["snow"]                   = 0xfffafa;
-	colors["springgreen"]            = 0x00ff7f;
-	colors["steelblue"]              = 0x4682b4;
-	colors["tan"]                    = 0xd2b48c;
-	colors["teal"]                   = 0x008080;
-	colors["thistle"]                = 0xd8bfd8;
-	colors["tomato"]                 = 0xff6347;
-	colors["turquoise"]              = 0x40e0d0;
-	colors["violet"]                 = 0xee82ee;
-	colors["wheat"]                  = 0xf5deb3;
-	colors["white"]                  = 0xffffff;
-	colors["whitesmoke"]             = 0xf5f5f5;
-	colors["yellow"]                 = 0xffff00;
-	colors["yellowgreen"]            = 0x9acd32;
-
-}
-
-static const ColorContainer named_colors;
-
 static bool parseNamedColorString(const std::string &value, video::SColor &color)
 {
 	std::string color_name;
@@ -570,9 +531,8 @@ static bool parseNamedColorString(const std::string &value, video::SColor &color
 
 	color_name = lowercase(color_name);
 
-	std::map<const std::string, unsigned>::const_iterator it;
-	it = named_colors.colors.find(color_name);
-	if (it == named_colors.colors.end())
+	auto it = s_named_colors.find(color_name);
+	if (it == s_named_colors.end())
 		return false;
 
 	u32 color_temp = it->second;
@@ -580,21 +540,26 @@ static bool parseNamedColorString(const std::string &value, video::SColor &color
 	/* An empty string for alpha is ok (none of the color table entries
 	 * have an alpha value either). Color strings without an alpha specified
 	 * are interpreted as fully opaque
-	 *
-	 * For named colors the supplied alpha string (representing a hex value)
-	 * must be exactly two digits. For example:  colorname#08
 	 */
 	if (!alpha_string.empty()) {
-		if (alpha_string.length() != 2)
-			return false;
-
-		unsigned char d1, d2;
-		if (!hex_digit_decode(alpha_string.at(0), d1)
-				|| !hex_digit_decode(alpha_string.at(1), d2))
+		if (alpha_string.size() == 1) {
+			u8 d;
+			if (!hex_digit_decode(alpha_string[0], d))
+				return false;
+
+			color_temp |= ((d & 0xf) << 4 | (d & 0xf)) << 24;
+		} else if (alpha_string.size() == 2) {
+			u8 d1, d2;
+			if (!hex_digit_decode(alpha_string[0], d1)
+					|| !hex_digit_decode(alpha_string[1], d2))
+				return false;
+
+			color_temp |= ((d1 & 0xf) << 4 | (d2 & 0xf)) << 24;
+		} else {
 			return false;
-		color_temp |= ((d1 & 0xf) << 4 | (d2 & 0xf)) << 24;
+		}
 	} else {
-		color_temp |= 0xff << 24;  // Fully opaque
+		color_temp |= 0xff << 24; // Fully opaque
 	}
 
 	color = video::SColor(color_temp);
@@ -602,6 +567,22 @@ static bool parseNamedColorString(const std::string &value, video::SColor &color
 	return true;
 }
 
+bool parseColorString(const std::string &value, video::SColor &color, bool quiet,
+		unsigned char default_alpha)
+{
+	bool success;
+
+	if (value[0] == '#')
+		success = parseHexColorString(value, color, default_alpha);
+	else
+		success = parseNamedColorString(value, color);
+
+	if (!success && !quiet)
+		errorstream << "Invalid color: \"" << value << "\"" << std::endl;
+
+	return success;
+}
+
 void str_replace(std::string &str, char from, char to)
 {
 	std::replace(str.begin(), str.end(), from, to);