#define __COMMANDS_HXX
-#include <string>
+#include <simgear/compiler.h>
+
+#include STL_STRING
#include <map>
#include <vector>
#include "props.hxx"
-using std::string;
-using std::map;
-using std::vector;
+SG_USING_STD(string);
+SG_USING_STD(map);
+SG_USING_STD(vector);
+
+
+/**
+ * Stored state for a command.
+ *
+ * <p>This class allows a command to cache parts of its state between
+ * invocations with the same parameters. Nearly every command that
+ * actually uses this will subclass it in some way. The command
+ * allocates the structure, but it is up to the caller to delete it
+ * when it is no longer necessary, unless the command deletes it
+ * and replaces the value with 0 or another command-state object
+ * first.</p>
+ *
+ * <p>Note that this class is for caching only; all of the information
+ * in it must be recoverable by other means, since the state could
+ * arbitrarily disappear between invocations if the caller decides to
+ * delete it.</p>
+ *
+ * <p>By default, the command state includes a place to keep a copy of
+ * the parameters.</p>
+ *
+ * @author David Megginson, david@megginson.com
+ */
+class SGCommandState
+{
+public:
+ SGCommandState ();
+ SGCommandState (const SGPropertyNode * args);
+ virtual ~SGCommandState ();
+ virtual void setArgs (const SGPropertyNode * args);
+ virtual const SGPropertyNode * getArgs () const { return _args; }
+private:
+ SGPropertyNode * _args;
+};
/**
* Manage commands.
*
* <p>This class allows the application to register and unregister
- * commands, and provides shortcuts for executing them. Commands
- * are simple functions that take a const pointer to an SGPropertyNode
- * as an argument and return a bool value indicating success or failure.
- * The property node may be ignored, or it may contain values that
- * the command uses as parameters.</p>
+ * commands, and provides shortcuts for executing them. Commands are
+ * simple functions that take a const pointer to an SGPropertyNode and
+ * a pointer to a pointer variable (which should be 0 initially) where
+ * the function can store compiled copies of its arguments, etc. to
+ * avoid expensive recalculations. If the command deletes the
+ * SGCommandState, it must replace it with a new pointer or 0;
+ * otherwise, the caller is free to delete and zero the pointer at any
+ * time and the command will start fresh with the next invocation.
+ * The command must return a bool value indicating success or failure.
+ * The property node may be ignored, or it may contain values that the
+ * command uses as parameters.</p>
*
* <p>There are convenience methods for invoking a command function
* with no arguments or with a single, primitive argument.</p>
/**
* Type for a command function.
*/
- typedef bool (*command_t) (const SGPropertyNode * arg);
+ typedef bool (*command_t) (const SGPropertyNode * arg,
+ SGCommandState ** state);
/**
* @return true if the command is present and executes successfully,
* false otherwise.
*/
- virtual bool execute (const string &name, const SGPropertyNode * arg) const;
-
-
- /**
- * Execute a command with no argument.
- *
- * The command function will receive a pointer to a property node
- * with no value and no children.
- *
- * @param name The name of the command.
- * @return true if the command is present and executes successfully,
- * false otherwise.
- */
- virtual bool execute (const string &name) const;
-
-
- /**
- * Execute a command with a single bool argument.
- *
- * The command function will receive a pointer to a property node
- * with a bool value and no children.
- *
- * @param name The name of the command.
- * @param arg The bool argument to the command.
- * @return true if the command is present and executes successfully,
- * false otherwise.
- */
- virtual bool execute (const string &name, bool arg) const;
-
-
- /**
- * Execute a command with a single int argument.
- *
- * The command function will receive a pointer to a property node
- * with a int value and no children.
- *
- * @param name The name of the command.
- * @param arg The int argument to the command.
- * @return true if the command is present and executes successfully,
- * false otherwise.
- */
- virtual bool execute (const string &name, int arg) const;
-
-
- /**
- * Execute a command with a single long argument.
- *
- * The command function will receive a pointer to a property node
- * with a long value and no children.
- *
- * @param name The name of the command.
- * @param arg The long argument to the command.
- * @return true if the command is present and executes successfully,
- * false otherwise.
- */
- virtual bool execute (const string &name, long arg) const;
-
-
- /**
- * Execute a command with a single float argument.
- *
- * The command function will receive a pointer to a property node
- * with a float value and no children.
- *
- * @param name The name of the command.
- * @param arg The float argument to the command.
- * @return true if the command is present and executes successfully,
- * false otherwise.
- */
- virtual bool execute (const string &name, float arg) const;
-
-
- /**
- * Execute a command with a single double argument.
- *
- * The command function will receive a pointer to a property node
- * with a double value and no children.
- *
- * @param name The name of the command.
- * @param arg The double argument to the command.
- * @return true if the command is present and executes successfully,
- * false otherwise.
- */
- virtual bool execute (const string &name, double arg) const;
-
-
- /**
- * Execute a command with a single string argument.
- *
- * The command function will receive a pointer to a property node
- * with a string value and no children.
- *
- * @param name The name of the command.
- * @param arg The string argument to the command.
- * @return true if the command is present and executes successfully,
- * false otherwise.
- */
- virtual bool execute (const string &name, string arg) const;
+ virtual bool execute (const string &name,
+ const SGPropertyNode * arg,
+ SGCommandState ** state) const;
+
+
+// /**
+// * Execute a command with no argument.
+// *
+// * The command function will receive a pointer to a property node
+// * with no value and no children.
+// *
+// * @param name The name of the command.
+// * @return true if the command is present and executes successfully,
+// * false otherwise.
+// */
+// virtual bool execute (const string &name) const;
+
+
+// /**
+// * Execute a command with a single bool argument.
+// *
+// * The command function will receive a pointer to a property node
+// * with a bool value and no children.
+// *
+// * @param name The name of the command.
+// * @param arg The bool argument to the command.
+// * @return true if the command is present and executes successfully,
+// * false otherwise.
+// */
+// virtual bool execute (const string &name, bool arg) const;
+
+
+// /**
+// * Execute a command with a single int argument.
+// *
+// * The command function will receive a pointer to a property node
+// * with a int value and no children.
+// *
+// * @param name The name of the command.
+// * @param arg The int argument to the command.
+// * @return true if the command is present and executes successfully,
+// * false otherwise.
+// */
+// virtual bool execute (const string &name, int arg) const;
+
+
+// /**
+// * Execute a command with a single long argument.
+// *
+// * The command function will receive a pointer to a property node
+// * with a long value and no children.
+// *
+// * @param name The name of the command.
+// * @param arg The long argument to the command.
+// * @return true if the command is present and executes successfully,
+// * false otherwise.
+// */
+// virtual bool execute (const string &name, long arg) const;
+
+
+// /**
+// * Execute a command with a single float argument.
+// *
+// * The command function will receive a pointer to a property node
+// * with a float value and no children.
+// *
+// * @param name The name of the command.
+// * @param arg The float argument to the command.
+// * @return true if the command is present and executes successfully,
+// * false otherwise.
+// */
+// virtual bool execute (const string &name, float arg) const;
+
+
+// /**
+// * Execute a command with a single double argument.
+// *
+// * The command function will receive a pointer to a property node
+// * with a double value and no children.
+// *
+// * @param name The name of the command.
+// * @param arg The double argument to the command.
+// * @return true if the command is present and executes successfully,
+// * false otherwise.
+// */
+// virtual bool execute (const string &name, double arg) const;
+
+
+// /**
+// * Execute a command with a single string argument.
+// *
+// * The command function will receive a pointer to a property node
+// * with a string value and no children.
+// *
+// * @param name The name of the command.
+// * @param arg The string argument to the command.
+// * @return true if the command is present and executes successfully,
+// * false otherwise.
+// */
+// virtual bool execute (const string &name, string arg) const;
private:
};
-#endif __COMMANDS_HXX
+#endif // __COMMANDS_HXX
// end of commands.hxx
projects / simgear.git / blobdiff