Cycles Standalone: Support for relative paths and string OSL parameters.

Patch by John Haddon.
Differential Revision: https://developer.blender.org/D418

intern/cycles/app/cycles_xml.cpp

@@ -406,7 +406,9 @@ static void xml_read_shader_graph(const XMLReadState& state, Shader *shader, pug
 
 			/* Source */
 			xml_read_string(&osl->filepath, node, "src");
+			if(path_is_relative(osl->filepath)) {
 				osl->filepath = path_join(state.base, osl->filepath);
+			}
 
 			/* Generate inputs/outputs from node sockets
 			 *
@@ -763,6 +765,9 @@ static void xml_read_shader_graph(const XMLReadState& state, Shader *shader, pug
 							case SHADER_SOCKET_NORMAL:
 								xml_read_float3(&in->value, node, attr.name());
 								break;
+							case SHADER_SOCKET_STRING:
+								xml_read_ustring( &in->value_string, node, attr.name() );
+								break;
 							default:
 								break;
 						}

intern/cycles/util/util_path.cpp

@@ -111,6 +111,11 @@ string path_escape(const string& path)
 	return result;
 }
 
+bool path_is_relative(const string& path)
+{
+	return to_boost(path).is_relative();
+}
+
 bool path_exists(const string& path)
 {
 	return boost::filesystem::exists(to_boost(path));

intern/cycles/util/util_path.h

@@ -41,6 +41,7 @@ string path_filename(const string& path);
 string path_dirname(const string& path);
 string path_join(const string& dir, const string& file);
 string path_escape(const string& path);
+bool path_is_relative(const string& path);
 
 /* file info */
 bool path_exists(const string& path);