exact distance for mouse, improved dashes

[perl-landing-airplanes.git] / trace-path.pl

diff --git a/trace-path.pl b/trace-path.pl
index 77a378d..c0d695d 100755 (executable)
--- a/trace-path.pl
+++ b/trace-path.pl
@@ -9,15 +9,23 @@ use SDL::Color;
 use SDL::Constants;
 use SDL::Event;
 use Math::CatmullRom;
-#use Algorithm::Line::Bresenham;
+use Algorithm::Line::Bresenham qw(line);
 
-use Carp qw/confess/;
-use Data::Dump qw/dump/;
+use Carp qw(cluck);
+use Data::Dump qw(dump);
+
+our $debug = 0;
 
 my ( $w, $h ) = ( 800, 480 );
 my $mouse_trashold = 10;
 my $max_path_length = 200;
 
+sub debug {
+       return unless $debug;
+       my ($package, $filename, $line) = caller;
+       warn '# ', dump( @_ ), " $filename +$line\n";
+}
+
 our $app = SDL::App->new(
        -width  => $w,
        -height => $h,
@@ -30,26 +38,39 @@ our $event = SDL::Event->new;
 
 our $mouse_down = 0;
 
-our $white = SDL::Color->new( 0xff, 0xff, 0xff );
-our $red   = SDL::Color->new( 0xff, 0x00, 0x00 );
-our $black = SDL::Color->new( 0x00, 0x00, 0x00 );
+our $mouse_color = SDL::Color->new( 0x00, 0x00, 0x80 );
+our $path_color  = SDL::Color->new( 0xff, 0xff, 0x80 );
+our $black       = SDL::Color->new( 0x00, 0x00, 0x00 );
 
 my ( $last_x, $last_y ) = ( 0,0 );
 
-my @path;
+our @path;
+sub reset_path { @path = () }
 
 sub curve {
-       return unless $#path > 4;
-       my $curve = Math::CatmullRom->new( splice @path, 0, $#path + $#path / 2 );
-       my @curve = $curve->curve( $mouse_trashold * $max_path_length / 2 );
-       warn "curve ", dump @curve;
+       if ( $#path < ( 4 * 2 - 1 ) ) { # less than 4 points
+               warn "path too short ", dump @path;
+               reset_path;
+               return;
+       }
+
+       my $curve = Math::CatmullRom->new( @path );
+       my $points = $#path + 1 - 4; # remove start/end points
+       my @curve = $curve->curve( $points );
+       debug 'curve' => @curve;
 
        my $i = 0;
-       while ( $i < $#curve ) {
-               my $rect = SDL::Rect->new( -x => int($curve[$i++]), -y => int($curve[$i++]), -w => 1, -h => 1 );
-               $app->fill( $rect, $red );
-               $app->update( $rect );
+       while ( $i <= $#curve - 4 ) {
+               line(
+                       int($curve[$i++]),
+                       int($curve[$i++]),
+                       int($curve[$i++]),
+                       int($curve[$i++]),
+                       sub { $app->pixel( @_, $path_color ) }
+               );
        }
+       $app->sync;
+       reset_path;
 }
 
 sub handle_events {
@@ -58,39 +79,42 @@ sub handle_events {
                my $type = $event->type();
 
                if ( $type == SDL_MOUSEBUTTONDOWN() ) {
-                       warn "mouse down ", $event->button_x, ' ', $event->button_y;
+                       debug 'mouse down', $event->button_x, $event->button_y;
                        $mouse_down = 1;
                } elsif ( $type == SDL_MOUSEBUTTONUP() ) {
-                       warn "mouse up ", $event->button_x, ' ', $event->button_y;
+                       debug 'mouse up', $event->button_x, $event->button_y;
                        $mouse_down = 0;
                        curve;
                } elsif ( $type == SDL_QUIT() ) {
                        exit;
                } elsif ( $type == SDL_KEYDOWN() ) {
                        my $key = $event->key_name;
-                       warn "key down $key\n";
+                       debug 'key down', $key;
                        exit if $key =~ m/^[xq]$/;
-                       if ( $key eq 's' ) {
+                       if ( $key eq 's' ) { # XXX draw curve
                                curve;
-                       } elsif ( $key eq 'd' ) {
-                               @path = ();
+                       } elsif ( $key eq 'backspace' ) { # XXX clean screen
+                               reset_path;
                                my $rect = SDL::Rect->new( -x => 0, -y => 0, -w => $w, -h => $h );
                                $app->fill( $rect, $black );
                                $app->update( $rect );
+                       } elsif ( $key eq 'd' ) { # XXX toggle debug
+                               $debug = ! $debug;
+                               warn "debug $debug\n";
+                       } else {
+                               warn "unknown key $key";
                        }
                } elsif ( $type == SDL_KEYUP() ) {
-                       warn "key up ", $event->key_name,$/;
+                       debug 'key up', $event->key_name;
                } elsif ( $type == SDL_MOUSEMOTION() ) {
-#                      warn "mouse ", $event->motion_xrel, ' ', $event->motion_yrel;
                        my ( $x, $y ) = ( $event->motion_x, $event->motion_y );
-                       warn "mouse $mouse_down @ $x*$y\n";
-                       my $dx = abs( $last_x - $x );
-                       my $dy = abs( $last_y - $y );
-                       if ( $mouse_down && ( $dx > $mouse_trashold || $dy > $mouse_trashold ) ) {
+                       #debug 'mouse', $mouse_down, $x, $y;
+                       my $d = sqrt( ( $x - $last_x ) ** 2 + ( $y - $last_y ) ** 2 );
+                       if ( $mouse_down && $d > $mouse_trashold ) {
                                if ( $#path < $max_path_length ) {
                                        push @path, $x, $y;
-                                       my $rect = SDL::Rect->new( -x => $event->motion_x, -y => $event->motion_y, -w => 3, -h => 3 );
-                                       $app->fill( $rect, $white );
+                                       my $rect = SDL::Rect->new( -x => $event->motion_x - 1, -y => $event->motion_y -1 , -w => 3, -h => 3 );
+                                       $app->fill( $rect, $mouse_color );
                                        $app->update( $rect );
                                        $last_x = $x;
                                        $last_y = $y;
@@ -100,7 +124,7 @@ sub handle_events {
                                }
                        }
                } else {
-                       warn "unknown $type\n";
+                       warn "unknown type $type\n";
                }
        }
 };