gii_key_event(3)

1gii_key_event(3)                      GGI                     gii_key_event(3)
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NAME

6       gii_key_event : LibGII key events
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SYNOPSIS

9       #include <ggi/events.h>
10
11       typedef struct gii_key_event {
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13           COMMON_DATA;
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15           uint32_t  modifiers;
16           uint32_t  sym;
17           uint32_t  label;
18           uint32_t  button;
19
20       } gii_key_event;
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22

DESCRIPTION

24       The gii_key_event structure represents key/button events from keyboards
25       and other devices.
26

GENERATED EVENTS

28       evKeyPress
29              The key specified in the structure is  pressed.  Not  repeatedly
30              produced while holding down the key.
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33       evKeyRelease
34              A key specified in the structure is released.
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36
37       evKeyRepeat
38              Makes  sense  when  dealing with character input. A key is being
39              held down and the character should  be  processed  at  intervals
40              when the key is held down.
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42              The  key  repeat rate and the delay before repeat is unspecified
43              and depends on the user's environment.
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45

STRUCTURE MEMBERS

47       modifiers
48              Result of bitwise-or of the following flags, indicating  certain
49              shift states:
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51              ·   GII_MOD_SHIFT
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53              ·   GII_MOD_CTRL
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55              ·   GII_MOD_ALT
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57              ·   GII_MOD_META
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59              ·   GII_MOD_SUPER
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61              ·   GII_MOD_HYPER
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63              ·   GII_MOD_ALTGR
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65              ·   GII_MOD_CAPS
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67              ·   GII_MOD_NUM
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69              ·   GII_MOD_SCROLL
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71       sym    The symbol of the key, which is the resultant character produced
72              by the key. This is roughly a transformation of the  label  with
73              the current modifiers. It also depends on the user's key config‐
74              uration.
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77       label  The actual label visible on the key in question.  This is either
78              the  symbol  produced  when  there are no modifiers or it is the
79              most prominent symbol on that key.  For example:
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81              ·   The numeric keys on top of the letter keys on a standard  PC
82                  keyboard have label values which are the digit characters in
83                  ASCII.
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85              ·   The English letter keys on a keyboard are represented  by  A
86                  through  Z in label. Although in their unshifted state these
87                  keys produce lowercase letters, the keycaps are printed with
88                  uppercase by convention, so this is what LibGII returns.
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90              label can be used as a generalized, portable keycode or scancode
91              of the key (That is, if the documentation  for  an  applications
92              says  that something is is mapped to key y, it is, even for Ger‐
93              man keyboard, where y and z are swapped)
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95
96       button The button number distinguishing between the  different  buttons
97              on the device.  For example, on a keyboard it is a number from 0
98              to 127 (i.e. a scancode), on a joystick it might be 1 to 4,  and
99              on a spaceorb it will be 1 to 8.
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101
102       If  an  application is interested in what physical keys are pressed and
103       released (most games for example), read the label  field.  Usually  the
104       modifiers in effect are irrelevant for these applications (however, for
105       non-alphanumeric symbols like + and -, it is  wise  to  check  the  sym
106       field  instead  of label as they are accessed using shifts on some key‐
107       board configurations).
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109       If an application wants a stream of characters  (for  text  input),  it
110       should read the sym field.
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GGI KEYSYM SYSTEM

113       In  GGI,  key  values are defined in ggi/keyboard.h. They are basically
114       Unicode characters with some extensions:
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116       Keys which are not represented by codepoints in  the  Unicode  standard
117       (such  as  the numeric keypad keys) are assigned codepoints in the pri‐
118       vate range. Applications should use the GIIK_ #defines for representing
119       these  keys.   These  codepoints  are  used in label, but they can also
120       occur in sym when the symbol is not any  character  (e.g.  arrow  keys,
121       function keys).
122
123       The  GIIUC_  #defines represent normal Unicode characters. The #defines
124       are interchangeable with  their  corresponding  codepoint  scalars  and
125       their  use  is optional. However, it is recommended to use them for the
126       symbols GIIUC_BackSpace, GIIUC_Return, GIIUC_Escape and GIIUC_Delete.
127              Important: In the LibGII system, no key is guaranteed to  exist;
128              the  key  values  are  for  identification  only.  Particularly,
129              applications should not rely on their presence.   Also,  because
130              not  all  keyboards are configured in the same way, applications
131              are encouraged to allow user configuration of the keys used  and
132              not hard-code their values.
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NAME

SYNOPSIS

DESCRIPTION

GENERATED EVENTS

STRUCTURE MEMBERS

GGI KEYSYM SYSTEM

SEE ALSO