NAME

       SDLx::Controller::Interface - Interface Physics and Rendering with the Controller with
       callbacks

CATEGORY

       Extension, Controller

SYNOPSIS

        use SDL;
        use SDLx::App;
        use SDLx::Controller::Interface;

        #SDLx::App is a controller
        my $app = SDLx::App->new(width => 200, height => 200 );

        my $ball = SDLx::Controller::Interface->new( x=> 10, y => 50, v_x => 10, v_y=> 20 );
        #Set the initial state of the ball's physics, this is optional

        $ball->set_acceleration(
           sub {
                     my ($time, $current_state) = @_;
                     return( 0, -10, 0 ); # Return accelerations (x,y,rotation)
               }
        );

        my $ball_render = sub {
              my $state = shift;

              $app->draw_rect( undef, 0 );
              $app->draw_rect( [$state->x, $state->y, 10,10], [255,0,0,255] );
              $app->update();
        };

        $ball->attach( $app, $ball_render, @params );

        $app->run();

        $ball->detach(); #can be called at anytime (for example when ball 'dies')

DESCRIPTION

METHODS

   set_acceleration
       Allows you to set the acceleration callback for defining the interface's behaviour in
       terms of x,y and rotation.

         $interface->set_acceleration (
             sub {
                my ($time, $current_state) = @_;

                return ( $accel_x, $accel_y, $torque );
             }
         );

       These accelerations are arbitrary and can be set to any frame of reference.  Your render
       callback will handle how to interpret it.

       The callback will receive the time and the current state as a "SDLx::Controller::State"
       element.

   attach
       Attaches the interface to a controller with a render callback

         $interface->attach( $controller, $render, @params );

       Where $render is a callback that receives the interpolated "SDLx::Controller::State".

         my $render = sub {
               my ($state, @params) = @_;
               # draw the current $state.
         };

       The @params are any extra parameters you would like to pass to the $render callback.

   current
         my $current_state = $interface->current();

       Returns the current state of the interface as a "SDLx::Controller::State".

   previous
         my $previous_state = $interface->previous();

       Returns the previous state of the interface as a "SDLx::Controller::State".

   detach
         $interface->detach();

       If $interface has been "attach()"'ed to any controller it will be detached now.

OTHER METHODS

       Don't use these unless you really really want to.

   acceleration
       Call the acceleration callback once.

   interpolate
       Interpolate the current state

   evaluate
       Evaluate the new current and previous state.

   update
       Update the states by integrating with time.

AUTHORS

       See "AUTHORS" in SDL.