os: introduce Input::Event::CHARACTER type

Character events are created via a dedicated 'Event' constructor that
takes an 'Event:Utf8' object as argument. Internally, the character is
kept in the '_code' member. The 'Utf8' value can by retrieved by the
recipient via the new 'utf8' method.

Issue #2264
This commit is contained in:
Norman Feske 2017-01-30 15:50:04 +01:00
parent 762728fee0
commit 859d23d92b
1 changed files with 41 additions and 8 deletions

View File

@ -23,40 +23,66 @@ class Input::Event
{
public:
enum Type { INVALID, MOTION, PRESS, RELEASE, WHEEL, FOCUS, LEAVE, TOUCH };
enum Type { INVALID, MOTION, PRESS, RELEASE, WHEEL, FOCUS, LEAVE, TOUCH,
CHARACTER };
private:
Type _type;
Type _type = INVALID;
/*
* For PRESS and RELEASE events, '_code' contains the key code.
* For FOCUS events, '_code' is set to 1 (focus) or 0 (unfocus).
*/
int _code;
int _code = 0;
/*
* Absolute pointer position coordinates
*/
int _ax, _ay;
int _ax = 0, _ay = 0;
/*
* Relative pointer motion vector
*/
int _rx, _ry;
int _rx = 0, _ry = 0;
public:
/**
* Constructors
* UTF8-encoded symbolic character
*/
Event():
_type(INVALID), _code(0), _ax(0), _ay(0), _rx(0), _ry(0) { }
struct Utf8
{
typedef unsigned char byte;
byte b0, b1, b2, b3;
Utf8(byte b0, byte b1 = 0, byte b2 = 0, byte b3 = 0)
: b0(b0), b1(b1), b2(b2), b3(b3) { }
};
/**
* Default constructor creates an invalid event
*/
Event() { }
/**
* Constructor creates a low-level event
*/
Event(Type type, int code, int ax, int ay, int rx, int ry):
_type(type), _code(code),
_ax(ax), _ay(ay), _rx(rx), _ry(ry) { }
/**
* Constructor creates a symbolic character event
*/
Event(Utf8 const &utf8)
:
_type(CHARACTER),
_code(((unsigned)utf8.b3 << 24) | ((unsigned)utf8.b2 << 16) |
((unsigned)utf8.b1 << 8) | ((unsigned)utf8.b0 << 0))
{ }
/**
* Accessors
*/
@ -67,6 +93,13 @@ class Input::Event
int rx() const { return _rx; }
int ry() const { return _ry; }
/**
* Return symbolic character encoded as UTF8 byte sequence
*
* This method must only be called if type is CHARACTER.
*/
Utf8 utf8() const { return Utf8(_code, _code >> 8, _code >> 16, _code >> 24); }
/**
* Return key code for press/release events
*/