Pongo el código y la imagen por si no la teneis para probar:
PROGRAM Expand;
private
xS[3]; //Coordenadas de las eskinas
yS[3];
vert,select;
begin
//full_screen = false;
//graph_mode = mode_16bits;
//set_fps(0,0);
set_mode(320, 240, 32);
set_fps(60, 0);
write_int(0,0,0,0,&fps);
graph = load_png("Homer.png");
write(0,21,29,4,"1");
write(0,139,29,4,"2");
write(0,139,171,4,"3");
write(0,21,171,4,"4");
write(0,160,10,4,"Utiliza 1,2,3,4 para elegir");
write(0,160,20,4,"vértice y cursores para moverlo");
write(0,160,190,4,"Vértice elegido:");
write_int(0, 220, 190, 4, &vert);
x = 80;
y = 100;
xS[0] = xS[3] = 181;
xS[1] = xS[2] = 299;
yS[0] = yS[1] = 29;
yS[2] = yS[3] = 171;
loop
if (key(_1)) select = 0; end
if (key(_2)) select = 1; end
if (key(_3)) select = 2; end
if (key(_4)) select = 3; end
if (key(_left)) xS[select]--; end
if (key(_right)) xS[select]++; end
if (key(_up)) yS[select]--; end
if (key(_down)) yS[select]++; end
vert = select+1;
map_clear(0,0,0);
expand(file, graph, xs[0], ys[0], xs[1], ys[1], xs[2], ys[2], xs[3], ys[3], 0, 0);
if (key(_esc)) exit(0,0); end
frame;
end
end