The menu code sucks!

- Joystick devices now send key up events for any buttons that are held
  down when they are destroyed.
- Changed the joystick enable-y menu items to be nonrepeatable so that you
  can't create several device scans per second. Changing them with a
  controller is also disabled so that you can't, for example, toggle XInput
  support using an XInput controller and have things go haywire when the
  game receives an infinite number of key down events when the controller
  is reinitialized with the other input system.
- Changed menu input to use a consolidated set of buttons, so most menus
  can be navigated with a controller as well as a keyboard.
- Changed the way that X/Y analog axes are converted to digital axes.
  Previously, this was done by checking if each axis was outside its deadzone.
  Now they are checked together based on their angle, so straight up/down/
  left/right are much easier to achieve.


SVN r1739 (trunk)

src/m_joy.cpp

@@ -33,6 +33,9 @@ CUSTOM_CVAR(Bool, use_joystick, false, CVAR_ARCHIVE|CVAR_GLOBALCONFIG|CVAR_NOINI
 
 // PRIVATE DATA DEFINITIONS ------------------------------------------------
 
+// Bits 0 is X+, 1 is X-, 2 is Y+, and 3 is Y-.
+static BYTE JoyAngleButtons[8] = { 1, 1+4, 4, 2+4, 2, 2+8, 8, 1+8 };
+
 // CODE --------------------------------------------------------------------
 
 //==========================================================================
@@ -170,26 +173,69 @@ void M_SaveJoystickConfig(IJoystickConfig *joy)
 
 double Joy_RemoveDeadZone(double axisval, double deadzone, BYTE *buttons)
 {
+	BYTE butt;
+
 	// Cancel out deadzone.
 	if (fabs(axisval) < deadzone)
 	{
 		axisval = 0;
-		*buttons = 0;
+		butt = 0;
 	}
 	// Make the dead zone the new 0.
 	else if (axisval < 0)
 	{
 		axisval = (axisval + deadzone) / (1.0 - deadzone);
-		*buttons = 2;	// button minus
+		butt = 2;	// button minus
 	}
 	else
 	{
 		axisval = (axisval - deadzone) / (1.0 - deadzone);
-		*buttons = 1;	// button plus
+		butt = 1;	// button plus
+	}
+	if (buttons != NULL)
+	{
+		*buttons = butt;
 	}
 	return axisval;
 }
 
+//===========================================================================
+//
+// Joy_XYAxesToButtons
+//
+// Given two axes, returns a button set for them. They should have already
+// been sent through Joy_RemoveDeadZone. For axes that share the same
+// physical stick, the angle the stick forms should determine whether or
+// not the four component buttons are present. Going by deadzone alone gives
+// you huge areas where you have to buttons pressed and thin strips where
+// you only have one button pressed. For DirectInput gamepads, there is
+// not much standard for how the right stick is presented, so we can only
+// do this for the left stick for those, since X and Y axes are pretty
+// standard. For XInput and Raw PS2 controllers, both sticks are processed
+// through here.
+//
+//===========================================================================
+
+int Joy_XYAxesToButtons(double x, double y)
+{
+	if (x == 0 && y == 0)
+	{
+		return 0;
+	}
+	double rad = atan2(y, x);
+	if (rad < 0)
+	{
+		rad += 2*M_PI;
+	}
+	// The circle is divided into eight segments for corresponding
+	// button combinations. Each segment is pi/4 radians wide. We offset
+	// by half this so that the segments are centered around the ideal lines
+	// their buttons represent instead of being right on the lines.
+	rad += M_PI/8;		// Offset
+	rad *= 4/M_PI;		// Convert range from [0,2pi) to [0,8)
+	return JoyAngleButtons[int(rad) & 7];
+}
+
 //===========================================================================
 //
 // Joy_GenerateButtonEvents