Add an include directive for colors files

A colors file can now specify other colors files, from which
additional node color specifications will be read. This allows, for
instance, using system-installed colors file for most colors,
and only overriding some of its colors in a custom colors file.

As a purpose of using a custom colors file may be to leave the colors
for some nodes undefined, it is now also possible to undefine a
previously defined node color (i.e. after reading another colors file
which defines a color for the node).

README.rst

@@ -89,6 +89,23 @@ colors <file>:
     # Entry that is used with 'drawalpha':
     default:water-source	78 132 212 64 224
 
+    The colors file can include other colors files using:
+    `@include filename`
+    Any entries after the inclusion point override entries from the
+    included file. Already defined colors can be 'undefined' by specifying
+    '-' as color:
+
+::
+
+    default:stone		71 68 67
+    # default-colors.txt might override the color of default:stone
+    @include default-colors.txt
+    # color of default:dirt_with_grass from default-colors.txt is overridden:
+    default:dirt_with_grass	82 117 54
+    # Color of water is undefined here:
+    default:water_source	-
+    default:water_flowing	-
+
 bgcolor:
     Background color of image, `--bgcolor #ffffff`
 

TileGenerator.cpp

@@ -325,9 +325,11 @@ void TileGenerator::setMaxY(int y)
 	m_reqYMaxNode = y - 16 * m_reqYMax;
 }
 
-void TileGenerator::parseColorsFile(const std::string &fileName)
+void TileGenerator::parseColorsFile(const std::string &fileName, int depth)
 {
-	if (verboseReadColors >= 2)
+	if (depth > 100)
+		throw std::runtime_error(std::string("Excessive inclusion depth of colors files - suspected recursion (i.e. cycle); current file: '") + fileName + "'");
+	if (depth == 0 && verboseReadColors >= 2)
 		cout << "Checking for colors file: " << fileName << std::endl;
 	ifstream in;
 	in.open(fileName.c_str(), ifstream::in);
@@ -337,7 +339,7 @@ void TileGenerator::parseColorsFile(const std::string &fileName)
 	}
 	if (verboseReadColors >= 1)
 		cout << "Reading colors file:  " << fileName << std::endl;
-	parseColorsStream(in, fileName.c_str());
+	parseColorsStream(in, fileName.c_str(), depth);
 	in.close();
 }
 
@@ -374,7 +376,7 @@ void TileGenerator::generate(const std::string &input, const std::string &output
 	printUnknown();
 }
 
-void TileGenerator::parseColorsStream(std::istream &in, const std::string &filename)
+void TileGenerator::parseColorsStream(std::istream &in, const std::string &filename, int depth)
 {
 	string line;
 	int linenr = 0;
@@ -388,45 +390,79 @@ void TileGenerator::parseColorsStream(std::istream &in, const std::string &filen
 		iline >> std::skipws;
 		string name;
 		ColorEntry color;
-		iline >> name;
+		iline >> name >> std::ws;
 		if (name.length() == 0)
 			continue;
-		int r, g, b, a, t;
+		if (name == "@include") {
-		iline >> r;
+			string includeFile;
-		iline >> g;
+			getline(iline,includeFile);
-		iline >> b;
+			size_t lastChar = includeFile.find_last_not_of(" \t\r\n");
-		if (iline.fail()) {
+			if (lastChar != string::npos)
-			std::cerr << filename << ":" << linenr << ": bad line in colors file (" << line << ")" << std::endl;
+				includeFile.erase(lastChar + 1);
-			continue;
+			if (includeFile == "") {
-		}
+				std::cerr << filename << ":" << linenr << ": include filename missing in colors file (" << line << ")" << std::endl;
-		a = 0xff;
+				continue;
-		iline >> a;
+			}
-		t = 0;
+#if ! (MSDOS || __OS2__ || __NT__ || _WIN32)
-		iline >> t;
+			// This same feature seems needlessly complicated on windows - so it is not supported
-		color = ColorEntry(r,g,b,a,t);
+			if (includeFile[0] != '/') {
-		if ((m_drawAlpha && a == 0xff) || (!m_drawAlpha && a != 0xff)) {
+				string includePath = filename;
-			// If drawing alpha, and the colors file contains both
+				size_t offset = includePath.find_last_of('/');
-			// an opaque entry and a non-opaque entry for a name, prefer
+				if (offset != string::npos) {
-			// the non-opaque entry
+					includePath.erase(offset);
-			// If not drawing alpha, and the colors file contains both
+					includeFile = includePath + '/' + includeFile;
-			// an opaque entry and a non-opaque entry for a name, prefer
-			// the opaque entry
-			// Otherwise, any later entry overrides any previous entry
-			ColorMap::iterator it = m_colors.find(name);
-			if (it != m_colors.end()) {
-				if (m_drawAlpha && (a == 0xff && it->second.a != 0xff)) {
-					// drawing alpha: don't use opaque color to override
-					// non-opaque color
-					continue;
-				}
-				if (!m_drawAlpha && (a != 0xff && it->second.a == 0xff)) {
-					// not drawing alpha: don't use non-opaque color to
-					// override opaque color
-					continue;
 				}
 			}
+#endif
+			parseColorsFile(includeFile, depth + 1);
+		}
+		else if (iline.good() && iline.peek() == '-') {
+			char c;
+			iline >> c >> std::ws;
+			if (iline.bad() || !iline.eof()) {
+				std::cerr << filename << ":" << linenr << ": bad line in colors file (" << line << ")" << std::endl;
+				continue;
+			}
+			m_colors.erase(name);
+		}
+		else {
+			int r, g, b, a, t;
+			iline >> r;
+			iline >> g;
+			iline >> b;
+			if (iline.fail()) {
+				std::cerr << filename << ":" << linenr << ": bad line in colors file (" << line << ")" << std::endl;
+				continue;
+			}
+			a = 0xff;
+			iline >> a;
+			t = 0;
+			iline >> t;
+			color = ColorEntry(r,g,b,a,t);
+			if ((m_drawAlpha && a == 0xff) || (!m_drawAlpha && a != 0xff)) {
+				// If drawing alpha, and the colors file contains both
+				// an opaque entry and a non-opaque entry for a name, prefer
+				// the non-opaque entry
+				// If not drawing alpha, and the colors file contains both
+				// an opaque entry and a non-opaque entry for a name, prefer
+				// the opaque entry
+				// Otherwise, any later entry overrides any previous entry
+				ColorMap::iterator it = m_colors.find(name);
+				if (it != m_colors.end()) {
+					if (m_drawAlpha && (a == 0xff && it->second.a != 0xff)) {
+						// drawing alpha: don't use opaque color to override
+						// non-opaque color
+						continue;
+					}
+					if (!m_drawAlpha && (a != 0xff && it->second.a == 0xff)) {
+						// not drawing alpha: don't use non-opaque color to
+						// override opaque color
+						continue;
+					}
+				}
+			}
+			m_colors[name] = color;
 		}
-		m_colors[name] = color;
 	}
 	if (!in.eof()) {
 		std::cerr << filename << ": error reading colors file after line " << linenr << std::endl;

TileGenerator.h

@@ -105,12 +105,12 @@ public:
 	void setTileOrigin(int x, int y);
 	void setTileCenter(int x, int y);
 	void enableProgressIndicator(void);
-	void parseColorsFile(const std::string &fileName);
+	void parseColorsFile(const std::string &fileName, int depth = 0);
 	void setBackend(std::string backend);
 	void generate(const std::string &input, const std::string &output);
 
 private:
-	void parseColorsStream(std::istream &in, const std::string &filename);
+	void parseColorsStream(std::istream &in, const std::string &filename, int depth);
 	std::string getWorldDatabaseBackend(const std::string &input);
 	void openDb(const std::string &input);
 	void loadBlocks();