NAME¶
SDL::Joystick -- SDL Bindings for the Joystick device
CATEGORY¶
Core, Joystick
SYNOPSIS¶
use SDL;
use SDL::Joystick;
SDL::init_sub_system(SDL_INIT_JOYSTICK);
die('no joystick found') unless(SDL::Joystick::num_joysticks());
my $joystick = SDL::Joystick->new(0);
METHODS¶
num_joysticks¶
int SDL::Joystick::num_joysticks( void );
Counts and returns available joysticks.
name¶
string SDL::Joystick::name( index );
Get the implementation dependent name of joystick. The "index"
parameter refers to the N'th joystick on the system.
my $num_joysticks = SDL::Joystick::num_joysticks();
printf("%d joysticks found\n", $num_joysticks);
for($i = 0; $i < $num_joysticks; $i++)
{
printf("%s\n", SDL::Joystick::name($i));
}
new¶
object SDL::Joystick->new( index );
Opens a joystick for use within SDL. The "index" refers to the N'th
joystick in the system. A joystick must be opened before it can be used.
# Initialize the joystick subsystem
SDL::init_sub_system(SDL_INIT_JOYSTICK);
# Check for joystick
if(SDL::Joystick::num_joysticks() > 0)
{
# Open joystick
my $joystick = SDL::Joystick->new(0);
if($joystick)
{
printf("Opened Joystick 0\n");
printf("Name: %s\n", SDL::Joystick::name(0));
printf("Number of Axes: %d\n", SDL::Joystick::num_axes($joystick));
printf("Number of Buttons: %d\n", SDL::Joystick::num_buttons($joystick));
printf("Number of Balls: %d\n", SDL::Joystick::num_balls($joystick));
}
else
{
printf("Couldn't open Joystick 0\n");
}
# Close if opened
SDL::Joystick::close($joystick) if SDL::Joystick::opened(0);
}
opened¶
int SDL::Joystick::opened( index );
Determines whether a joystick has already been opened within the application.
"index" refers to the N'th joystick on the system.
Returns 1 if the joystick has been opened, or 0 if it has not.
index¶
int SDL::Joystick::index( object );
Returns the "index" of a given "SDL_Joystick" structure. See
SDL::Joystick::new
num_axes¶
int SDL::Joystick::num_axes( object );
Return the number of axes available from a previously opened joystick. See
SDL::Joystick::new
num_balls¶
int SDL::Joystick::num_balls( object );
Return the number of trackballs available from a previously opened joystick. See
SDL::Joystick::new
num_hats¶
int SDL::Joystick::num_hats( object );
Gets the number of joystick hats from a previously opened joystick. See
SDL::Joystick::new
int SDL::Joystick::num_buttons( object );
Gets the number of joystick buttons from a previously opened joystick. See
SDL::Joystick::new
update¶
void SDL::Joystick::update();
Updates the state(position, buttons, etc.) of all open joysticks. If joystick
events have been enabled with "SDL::Joystick::event_state" then this
is called automatically in the event loop.
get_axis¶
"get_axis" returns the current state of the given axis on the given
joystick.
On most modern joysticks the X axis is usually represented by axis 0 and the Y
axis by axis 1. The value returned by "get_axis" is a signed integer
(-32768 to 32767) representing the current position of the axis, it may be
necessary to impose certain tolerances on these values to account for jitter.
Note: Some joysticks use axes 2 and 3 for extra buttons.
Returns a 16-bit signed integer representing the current position of the axis.
my $joystick = SDL::Joystick->new(0);
my $x_move = SDL::Joystick::get_axis($joystick, 0);
my $y_move = SDL::Joystick::get_axis($joystick, 1);
get_hat¶
int SDL::Joystick::get_hat( object, int );
"get_hat" returns the current state of the given "hat" on
the given "joystick".
The current state is returned which is an OR'd combination of one or more of the
following:
- •
- "SDL_HAT_CENTERED"
- •
- "SDL_HAT_UP"
- •
- "SDL_HAT_RIGHT"
- •
- "SDL_HAT_DOWN"
- •
- "SDL_HAT_LEFT"
- •
- "SDL_HAT_RIGHTUP"
- •
- "SDL_HAT_RIGHTDOWN"
- •
- "SDL_HAT_LEFTUP"
- •
- "SDL_HAT_LEFTDOWN"
my $joystick = SDL::Joystick->new(0);
my $position = SDL::Joystick::get_hat($joystick, 0);
print("hat is in position UP\n") if $position & SDL_HAT_UP;
int SDL::Joystick::get_button( object, int );
"get_button" returns the current state of the given button on the
given joystick.
Returns 1 if the button is pressed. Otherwise, 0.
my $joystick = SDL::Joystick->new(0);
my $num_buttons = SDL::Joystick::num_buttons($joystick);
for(my $i = 0; $i < $num_buttons; $i++)
{
printf("button %d is %s\n", $i, SDL::Joystick::get_button($joystick, $i) ? 'pressed' : 'not pressed');
}
SDL::Joystick::close($joystick) if SDL::Joystick::opened(0);
get_ball¶
int SDL::Joystick::get_ball(SDL_Joystick $joystick, int $ball, int $dx, int $dy);
Get the ball axis change.
Trackballs can only return relative motion since the last call to
SDL::Joystick::get_ball, these motion deltas are placed into "dx"
and "dy".
Returns 0 on success or -1 on failure
my $delta_x = 0;
my $delta_y = 0;
my $joystick = SDL::Joystick->new(0);
SDL::Joystick::update();
printf("TrackBall Read Error!\n") if(SDL::JoystickGetBall($joystick, 0, $delta_x, $delta_y) == -1);
printf("Trackball Delta- X:%d, Y:%d\n", delta_x, delta_y);
close¶
void SDL::Joystick::close( object );
Closes a previously opened joystick. See SDL::Joystick::new
SDL::Joystick::close($joystick) if SDL::Joystick::opened(0);
AUTHORS¶
See "AUTHORS" in SDL.