20 Jan
2006
20 Jan
'06
8:25 a.m.
On Friday 20 January 2006 12:31, Carlo Capocasa wrote:
[...]
I want to create a console keyboard to MIDI
application and for this
I would like to read the physical status of keyboard keys.
That is, MIDI output, as in sending MIDI messages to an onboard or
external hardware synth, or a softsynth running in the driver or as a
separate application? (As opposed to generating "wave" audio in your
application.)
Anyway, keybord input is done by handling "press" and "release"
events. When you get a "press" event, you set some state variable for
the corresponding key to "down", and when you get a "release" event,
you clear that state variable.
SDL also has an alternative API that has this logic built in:
SDL_GetKeyState():
'man SDL_GetKeyState':
----------------------------------------------------------------------
...
SYNOPSIS
#include "SDL.h"
Uint8 *SDL_GetKeyState(int *numkeys);
DESCRIPTION
Gets a snapshot of the current keyboard state. The
current state is return as a pointer to an array,
the size of this array is stored in numkeys. The
array is indexed by the SDLK_* symbols. A value of
1 means the key is pressed and a value of 0 means
its not. The pointer returned is a pointer to an
internal SDL array and should not be freed by the
caller.
Note:
Use SDL_PumpEvents to update the state array.
EXAMPLE
Uint8 *keystate = SDL_GetKeyState(NULL);
if ( keystate[SDLK_RETURN] )
printf("Return Key Pressed.");
...
----------------------------------------------------------------------
//David Olofson - Programmer, Composer, Open Source Advocate
.------- http://olofson.net - Games, SDL examples -------.
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