Scrolling Text with Scrollbar

var g_timer;
var i = 0;
var interval = 20;
var tw = 0;

//--------
var weight_normal =400;
var weight_bold =800;
var italic_no =0;
var italic =1;
var uline_no =0;
var uline =1;
//--------
var align_top =0;
var align_middle=1;
var align_bottom=2;

var align_left =0;
var align_center=1;
var align_right =2;

var trim_no =0;
var trim_chara =1;
var trim_word =2;
var trim_elips_chara =3;
var trim_elips_word =4;
var trim_elips_path =5;

var flag_rtl =0x0001;
var flag_vert =0x0002;
var flag_nofit =0x0004;
var flag_dispctrl =0x0020;
var flag_nofallback =0x0400;
var flag_trailspace =0x0800;
var flag_nowrap =0x1000;
var flag_linelimit =0x2000;
var flag_noclip =0x4000;

function StrFmt(alignH,alignV,trim,flag){ return ((alignH<<28)|(alignV<<24)|(trim<<20)|flag); }
//--------
function RGB(r,g,b){ return (0xff000000|(r<<16)|(g<<8)|(b)); }
function RGBA(r,g,b,a){ return ((a<<24)|(r<<16)|(g<<8)|(b)); }
//--------
function TimeFmt(t){
var zpad = function(n){
var str = n.toString();
return (str.length<2) ? "0"+str : str;
}
var h = Math.floor(t/3600); t-=h*3600;
var m = Math.floor(t/60); t-=m*60;
var s = Math.floor(t);
if(h>0) return h.toString()+":"+zpad(m)+":"+zpad(s);
return m.toString()+":"+zpad(s);
}
//----------------------------------------------------------------------------

var g_font = gdi.Font( "bitstream vera sans mono",40);
var g_font1 = gdi.Font( "bitstream vera sans mono",40);
var g_timeFmt = fb.TitleFormat("%playback_time%[ / %length%]");
var g_titleFmt = fb.TitleFormat("%ARTIST% - %title%");
var g_fileinfo = null;

var g_drag = 0;
var g_drag_seek = 0;

var tic_ArtistAlbumText= { size:26, step:1};
var tic_SongTimeText= { size:20, step: 2};

function on_paint(gr){

var pos = 0;
var length = fb.PlaybackLength;
var songTimeText;
var artistAlbumText;
if(length > 0){
if(g_drag){
pos = window.Width * g_drag_seek;
songTimeText= "Seek " + TimeFmt(g_drag_seek * length) + " / " + TimeFmt(length);
} else{
pos = window.Width * (fb.PlaybackTime / length);
songTimeText= g_timeFmt.Eval();
artistAlbumText = g_titleFmt.Eval();
}
}

gr.FillGradRect( 0, 50, pos, wh, 90, RGB(5,150,35), RGB(5,100,35)); //green scroll
gr.FillGradRect(pos, 50, ww-pos, wh, 90, RGB(0,0,0), RGB(0,0,0)); //black background

if(songTimeText==null) songTimeText= "";
gr.DrawString(getScrolledText(songTimeText, tic_SongTimeText), g_font1, RGB(255,255,255), 0, 50, ww-20, wh-50, StrFmt(align_right, align_center, trim_no, flag_nowrap | flag_noclip));
//-----------
var g_font = gdi.font("Tahoma", 34, 0);
gr.SetTextRenderingHint(5);

var text = fb.TitleFormat("%title% - %artist% - %album%").Eval();

tw = gr.CalcTextWidth(text, g_font);

     gr.FillGradRect(0,0,ww,50, 90, RGB(5,150,35), RGB(55,200,85));

if (fb.IsPlaying) {

if (g_timer) {

    gr.GdiDrawText(text, g_font, RGB(255,255,255), ww - i, 4, ww + tw, g_font.height + 5, format = 0)

}

}
//----------


}

function getScrolledText(txt,tic) {
if(txt.length<=tic.size)
return txt;
if(tic.val>=(txt.length+tic.spacer.length))
tic.val= 0;
else
tic.val+= tic.step;
return (txt+tic.spacer+txt).substring(tic.val, tic.val+tic.size);
}



function on_size(){

ww = window.Width;
wh = window.Height;

if (i == ww + tw) i = 0;

if (i == 0 && !g_timer) g_timer = window.CreateTimerInterval(interval);
}

function on_focus(focused){
//fb.trace("focus " + focused);
}
function on_key_down(key){
//fb.trace("key " + key);
}
function on_mouse_lbtn_down(x,y){
g_drag = 1;
}
function on_mouse_lbtn_up(x,y){
if(g_drag){
g_drag = 0;
g_drag_seek = x / window.Width;
g_drag_seek = (g_drag_seek<0) ? 0 : (g_drag_seek<1) ? g_drag_seek : 1;
fb.PlaybackTime = fb.PlaybackLength * g_drag_seek;
}
}
function on_mouse_move(x,y){
if(g_drag){
g_drag_seek = x / window.Width;
g_drag_seek = (g_drag_seek<0) ? 0 : (g_drag_seek<1) ? g_drag_seek : 1;
window.Repaint();
}
}
function on_mouse_wheel(delta){
//fb.trace("wheel " + delta);
}
//--------
function on_playback_starting(cmd, paused){

}
function on_playback_new_track(info){

  i = 0;

window.Repaint();
}
function on_playback_stop(reason){

window.Repaint();
}
function on_playback_seek(time){
window.Repaint();
}
function on_playback_pause(state){
}
function on_playback_edited(){
}
function on_playback_dynamic_info(){
}
function on_playback_dynamic_info_track(){
}
function on_playback_time(time){
window.RepaintRect(0,50,ww,wh);
}
function on_volume_change(val){
}
//EOF

//================================0


function on_timer(id) {

i = i + 1 * 1;
if (i == ww + tw) i = 0;
window.RepaintRect(ww - i ,0, tw + 20, 50);

}