X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Finput%2Fdevice.h;h=b42ed3fde4991feb8d87b05258831585db57efec;hb=2438c3cdd14087bfc3375ed1f5521ad5c0c09bbc;hp=49d858ba2a3eed92dbfb1fb6f9c83dabe474e06a;hpb=1023b38fa278cea71fba3d2881e1bfde930cd025;p=libs%2Fgui.git

diff --git a/source/input/device.h b/source/input/device.h
index 49d858b..b42ed3f 100644
--- a/source/input/device.h
+++ b/source/input/device.h
@@ -3,33 +3,60 @@
 
 #include <string>
 #include <vector>
+#include <stdexcept>
 #include <sigc++/signal.h>
 
 namespace Msp {
 namespace Input {
 
+class device_not_available: public std::runtime_error
+{
+public:
+	device_not_available(const std::string &w): std::runtime_error(w) { }
+	virtual ~device_not_available() throw() { }
+};
+
+
 /**
 Base class for input devices.  Input devices have two types of controls:
 buttons and axes.  Buttons are either on or off.  Axes have a floating point
-value in the range [-1, 1].
+value nominally in the range [-1, 1].
+
+Event handlers return a boolean indicating whether the event is considered
+processed.  If a handler returns true, no further handlers are invoked.
 */
 class Device
 {
+protected:
+	struct EventAccumulator
+	{
+		typedef void result_type;
+
+		template<typename Iter>
+		result_type operator()(Iter begin, Iter end) const
+		{
+			for(Iter i=begin; i!=end; ++i)
+				if(*i)
+					return;
+		}
+	};
+
 public:
-	sigc::signal<void, unsigned> signal_button_press;
-	sigc::signal<void, unsigned> signal_button_release;
-	sigc::signal<void, unsigned, float, float> signal_axis_motion;
+	sigc::signal<bool, unsigned>::accumulated<EventAccumulator> signal_button_press;
+	sigc::signal<bool, unsigned>::accumulated<EventAccumulator> signal_button_release;
+	sigc::signal<bool, unsigned, float, float>::accumulated<EventAccumulator> signal_axis_motion;
 
 protected:
 	std::string name;
-	std::vector<char>  buttons;
+	std::vector<char> buttons;
 	std::vector<float> axes;
 
-	Device() { }
+	Device();
 public:
-	virtual ~Device() { }
+	virtual ~Device();
+
 	const std::string &get_name() const { return name; }
-	bool  get_button_state(unsigned) const;
+	bool get_button_state(unsigned) const;
 	float get_axis_value(unsigned) const;
 
 	virtual std::string get_button_name(unsigned) const;