/*! Purpose:
 *  
 *  Scroll content in parameter "text" from right to left in peculiar Martinland fashion...
 *  
 *  History:
 *
 *  02/20/2021:	Release  
 *  02/19/2021:	Fine-tuning...
 *  02/18/2021:	Complete reimplementation in JavaScript: Java is borked now (20 years after the fact! ;-)
 *  02/17/2021:	Version 3.0
 *
 *			Now historical, original commentaries:
 *  
 *  07/21/2010:	removed deprecated (after 10 years!) code! 8-D
 *  07/21/2010:	put jitter back in...
 *  07/21/2010:	added double buffering because of annoying flicker on modern systems (10 years after! ;-)
 *  07/21/2010:	Version 2.0
 *  
 *  11/11/2000:	changed colorization
 *  11/09/2000:	added vector characters
 *  11/06/2000:	improved redraw; added comments; tightened code
 *  11/05/2000:	Version 1.0
 */

// Screen canvas and context
var sC = document.getElementById('mlCanvas');

if (sC) {	// Is there an element at all?

var sCC = sC.getContext('2d');

if (sCC) {	// Is there HTML5 support at all?

// Double buffer canvas and context
var sB = document.createElement('canvas');
sB.width=sC.width;
sB.height=sC.height;
var sBC = sB.getContext('2d');

// Click function for playing Martinland signation...
var mlSound = document.getElementById("mlSig");
function letsHearIt() { mlSound.play(); }

var sScale = sC.height / 6;		// Global scaling

var sText = "latest update may/01/2024: new joyful c64/theremin events arrived in thereminland - latest c64 tune is now part of the composer section - igor returns for all, thanks to ruffle - re-implementation of this routine 20 years after its creation, again at 3:00 am, see very end of this loong scroll text if you dare - martinland sings again for favourable browsers - three additional theremin events - five more synthesizer pieces resurrected into the media section below - cd release party vibes online, one year after the fact - one of my earliest compositions made it into the media section - adventure game _heroes_and_cowards_ finally out there - hurray, audio cd _thereminland_ has arrived: see media section below - more c-64 chiptunes and literature - welcome sam and max a la martinland - 3d-animated web experience _acousmonuments_ has been launched - found drawing, 24 years old - animation short _intersphere_ online now - thx-like intro animation plus ancient thx trailer test online now - after decades i finally completed my first german short story - found crazy old tape: in media section now - 3d animation intinahui released in theaters and on dvd, see movie palace at the right-hand side - mr.pixelpop cd cover art now in cartoon vault - dancing egg-shells are here - theremin updates - bio updates - about martinland flip books - more time-lapse retro scoring - retro computing sketches - mediabot is on the run - added five new lobert episodes - theremin updates - two ancient synthesizer pieces in the media section - sambucus nigra plant portraits - premiere of lomi rotoscope animation - retro poem audification in media section - new lobert comic strips in the vault - video game examples online now - an example of time-lapse retro scoring - a web page far, far away has been added - now featuring cropfm, the flexxxible radioshow - added _sailing island_ - cartoon-animated website abrahama sama clara - flip book w sound - about martinland - added _nachlage_ - first cartoon-animated website now hosted by trusty igor in the vault... - finally: after one year of preparations thereminland opens its gates in the media section - belated inclusion of vis-page - bio-page revamped - added new lobert strips plus _making of_ and 24 hour comic 2005 - welcome maxie, the girl of the future and tle-films - lobert now resides in cartoon vault - new blade runner music and borderline art in the media section - der kineast number 4 hits the cartoon vault - encounter with gonzo added to bio page - my second _24 hour comic_ hits the world - welcome the first _24 hour comic_ in the vault - found an old cartoon in a keyboard manual - celly now resides in the media section - der kineast 3 now in the vault - added original 8bit retro c64 musix - revamped bio page - the media-section now features the stop motion version of _auslage_ - _der kineast_ has been handed over to good ole igor in the cartoon vault - i have completed _mike special edition_ with over-the-top sound - jurassic loop special edition has arrived - let there be light special edition is online - _life on the edge_ has its premiere in the movie palace - added complete version of _18 months later_ to movie palace - welcome igor, who is taking care of the cartoon vault behind that door - electronic music for ars electronica festival - borderline art, both down in the media section - please welcome mike - i dug up more nostalgic instrumentals - _18 months later_, the first martinland film production is presented in the movie palace at the right-hand side - kali stars in _jurassic loop_ - _lara_ joined the team - vismax has entered the game - martinland, the radioshow, is on the air - added signation with flash and a smile towards john williams, plus more mp3z - find out what a yoobaa-sketch is... - _genie_ is taking flight in the media section - finally: the short _the frog that croaked too much_ gets online - big newsflash: _patrick_ has arrived - this java scroll is a monday 3:00 am job, by the way...";
var sWrap = -sScale * sText.length*2.85;		// X position after which scroll should wrap

var sX = sC.width + sScale*10;	// Current x position of scrolltext
var sY = sScale*2;			// Current y position of scrolltext
var sCX = 0;				// Current character x position
var sCY = 0;				// Current character y position

var sJF1, sJF2, sJF3, sJF4;		// Jitter factors

var sDelay = 18;				// Speed of scroll routine
var sTimeout;				// Timeout handle of scroll routine


//
// Draw transformed line in 2D-context cc from (x1,y1) to (x2,y2)
// 
// [Dimensions taken from global canvas sC]
// [Using global jitter factor sJF1 - sJF4]
// [Using global scale factor sScale and character position (sCX/sCY)]
//
function sDrwLine(cc, x1, y1, x2, y2) {
  var l1, l2, l3, l4;	// Auxiliary
  var ss1, ss2;		// Sine FX

  l1=x1*sScale + sCX + sJF1;
  l2=y1*sScale + sCY + sJF2;
  l3=x2*sScale + sCX + sJF3;
  l4=y2*sScale + sCY + sJF4;

  // Make cool sine scroll...
  ss1 = Math.sin((l1-sC.width/2)/16)*sScale/1.2 * Math.sin((l1-sC.width/2)/196)*sScale/1.2;
  ss2 = Math.sin((l3-sC.width/2)/16)*sScale/1.2 * Math.sin((l3-sC.width/2)/196)*sScale/1.2;

  if ((l1<(sC.width-16)) && (l3<(sC.width-16))) {  // Avoid right border clipping
    cc.beginPath();
    cc.moveTo(l1, l2+ss1);
    cc.lineTo(l3, l4+ss2);
    cc.stroke();
    }
  }


//
// Re-calculate jitter for character c
//
// [Using global jitter factor sJF1 - sJF4]
//
function sJitter(c) {
  if(c!='^') {	// New distortion triggered
    sJF1=(Math.random()-0.5)*2.5;
    sJF2=(Math.random()-0.5)*2.6;
    sJF3=(Math.random()-0.5)*2.5;
    sJF4=(Math.random()-0.5)*2.6;
    }
  else {		// Dampen distortion
    sJF1=sJF1*0.995;
    sJF2=sJF2*0.995;
    sJF3=sJF3*0.995;
    sJF4=sJF3*0.995;
    }
  }


//
// Draw character c in given context cc
//
// [Dimensions taken from global canvas sC]
// [Using global character position sCX]
// [Using global scale factor sScale]
//
function sDrwChar (cc, c) {
  var width = 0;		// Width of character in scaling units

  if ((sCX<1) || (sCX>sC.width+sScale*20)) {	// Nothing to draw here: Out of range!
    switch(c) {
      case 'i':
      case '1':
        width=1; break;
      case ' ':
        width=1.5; break;
      default:
        width=2; break;
      }
    sCX=sCX + (width+1)*sScale;
    return;
    }

  // Slow pace jitter
  if (Math.floor(sCX)%101==0) sJitter(c);
  else sJitter('^');

  switch (c) {
    case '0':
      sDrwLine(cc, 0, 0, 0, 2);
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 1, 2, 1, 0);
      sDrwLine(cc, 1, 0, 0, 0);
      width = 2;
      break;
    case '1':
      sDrwLine(cc, 0, 0, 0, 2);
      width = 1;
      break;
    case '2':
      sDrwLine(cc, 0, 0, 1, 0);
      sDrwLine(cc, 1, 0, 1, 1);
      sDrwLine(cc, 1, 1, 0, 1);
      sDrwLine(cc, 0, 1, 0, 2);
      sDrwLine(cc, 0, 2, 1, 2);
      width = 2;
      break;
    case '3':
      sDrwLine(cc, 0, 0, 1, 0);
      sDrwLine(cc, 1, 0, 1, 1);
      sDrwLine(cc, 1, 1, 0, 1);
      sDrwLine(cc, 1, 1, 1, 2);
      sDrwLine(cc, 0, 2, 1, 2);
      width = 2;
      break;
    case '4':
      sDrwLine(cc, 0, 0, 0 ,1);
      sDrwLine(cc, 0, 1, 1, 1);
      sDrwLine(cc, 1, 0, 1, 2);
      width = 2;
      break;
    case '5':
      sDrwLine(cc, 0, 0, 1, 0);
      sDrwLine(cc, 0, 0, 0 ,1);
      sDrwLine(cc, 0, 1, 1, 1);
      sDrwLine(cc, 1, 1, 1, 2);
      sDrwLine(cc, 1, 2, 0, 2);
      width = 2;
      break;
    case '6':
      sDrwLine(cc, 0, 0, 1, 0);
      sDrwLine(cc, 0, 0, 0 ,2);
      sDrwLine(cc, 0, 1, 1, 1);
      sDrwLine(cc, 1, 1, 1, 2);
      sDrwLine(cc, 1, 2, 0, 2);
      width = 2;
      break;
    case '7':
      sDrwLine(cc, 0, 0, 1, 0);
      sDrwLine(cc, 1, 0, 1 ,2);
      width = 2;
      break;
    case '8':
      sDrwLine(cc, 0, 0, 1, 0);
      sDrwLine(cc, 0, 0, 0 ,2);
      sDrwLine(cc, 0, 1, 1, 1);
      sDrwLine(cc, 1, 0, 1, 2);
      sDrwLine(cc, 0, 2, 1, 2);
      width = 2;
      break;
    case '9':
      sDrwLine(cc, 0, 0, 1, 0);
      sDrwLine(cc, 0, 0, 0 ,1);
      sDrwLine(cc, 0, 1, 1, 1);
      sDrwLine(cc, 1, 0, 1, 2);
      width = 2;
      break;
    case 'a':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 1.0/2.0, 1, 3.0/2.0, 1);
      sDrwLine(cc, 2, 0, 1, 2);
      width = 2;
      break;
    case 'b':
      sDrwLine(cc, 1, 0, 0, 2);
      sDrwLine(cc, 1.0/2.0, 1, 3.0/2.0, 1);
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 2, 0, 3.0/2.0, 1);
      sDrwLine(cc, 3.0/2.0, 1, 1, 2);
      width = 2;
      break;
    case 'c':
      sDrwLine(cc, 1, 0, 0, 2);
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 0, 2, 1, 2);
      width = 2;
      break;
    case 'd':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 1, 2, 3.0/2.0, 1);
      sDrwLine(cc, 3.0/2.0, 1, 1, 0);
      width = 2;
      break;
    case 'e':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 1.0/2.0, 1, 3.0/2.0, 1);
      sDrwLine(cc, 0, 2, 1, 2);
      width = 2;
      break;
    case 'f':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 1.0/2.0, 1, 3.0/2.0, 1);
      width = 2;
      break;
    case 'g':
      sDrwLine(cc, 1, 0, 0, 2);
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 1, 2, 3.0/2.0, 1);
      sDrwLine(cc, 1, 1, 3.0/2.0, 1);
      width = 2;
      break;
    case 'h':
      sDrwLine(cc, 1, 0, 0, 2);
      sDrwLine(cc, 1, 2, 2, 0);
      sDrwLine(cc, 1.0/2.0, 1, 3.0/2.0, 1);
      width = 2;
      break;
    case 'i':
      sDrwLine(cc, 1, 0, 0, 2);
      width = 1;
      break;
    case 'j':
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 1, 2, 2, 0);
      width = 2;
      break;
    case 'k':
      sDrwLine(cc, 1, 0, 0, 2);
      sDrwLine(cc, 1.0/2.0, 1, 2, 0);
      sDrwLine(cc, 1.0/2.0, 1, 1, 2);
      width = 2;
      break;
    case 'l':
      sDrwLine(cc, 1, 0, 0, 2);
      sDrwLine(cc, 0, 2, 1, 2);
      width = 2;
      break;
    case 'm':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 1, 0, 1, 1);
      sDrwLine(cc, 1, 1, 2, 0);
      sDrwLine(cc, 2, 0, 1, 2);
      width = 2;
      break;
    case 'n':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 1, 0, 1, 2);
      sDrwLine(cc, 1, 2, 2, 0);
      width = 2;
      break;
    case 'o':
      sDrwLine(cc, 1, 0, 0, 2);
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 1, 2, 2, 0);
      sDrwLine(cc, 2, 0, 1, 0);
      width = 2;
      break;
    case 'p':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 1.0/2.0, 1, 3.0/2.0, 1);
      sDrwLine(cc, 2, 0, 3.0/2.0, 1);
      width = 2;
      break;
    case 'q':
      sDrwLine(cc, 1, 0, 0, 2);
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 1, 2, 2, 0);
      sDrwLine(cc, 2, 0, 1, 0);
      sDrwLine(cc, 1, 2, 1, 1);
      width = 2;
      break;
    case 'r':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 1.0/2.0, 1, 3.0/2.0, 1);
      sDrwLine(cc, 1.0/2.0, 1, 1, 2);
      sDrwLine(cc, 2, 0, 3.0/2.0, 1);
      width = 2;
      break;
    case 's':
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 1, 2, 1, 0);
      sDrwLine(cc, 1, 0, 2, 0);
      width = 2;
      break;
    case 't':
      sDrwLine(cc, 3.0/2.0, 0, 1.0/2.0, 2);
      sDrwLine(cc, 1, 0, 2, 0);
      width = 2;
      break;
    case 'u':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 0, 2, 1, 2);
      sDrwLine(cc, 1, 2, 2, 0);
      width = 2;
      break;
    case 'v':
      sDrwLine(cc, 1.0/2.0, 2, 1, 0);
      sDrwLine(cc, 1.0/2.0, 2, 2, 0);
      width = 2;
      break;
    case 'w':
      sDrwLine(cc, 0, 2, 1, 0);
      sDrwLine(cc, 0, 2, 1, 1);
      sDrwLine(cc, 1, 1, 1, 2);
      sDrwLine(cc, 2, 0, 1, 2);
      width = 2;
      break;
    case 'x':
      sDrwLine(cc, 0, 2, 2, 0);
      sDrwLine(cc, 1, 0, 1, 2);
      width = 2;
      break;
    case 'y':
      sDrwLine(cc, 1.0/2.0, 2, 1, 1);
      sDrwLine(cc, 1, 1, 1, 0);
      sDrwLine(cc, 1, 1, 2, 0);
      width = 2;
      break;
    case 'z':
      sDrwLine(cc, 1, 0, 2, 0);
      sDrwLine(cc, 2, 0, 0, 2);
      sDrwLine(cc, 0, 2, 1, 2);
      width = 2;
      break;
    case ' ':
      width = 1.5;
      break;
    case '-':
      sDrwLine(cc, 0, 1, 1, 1);
      width = 2;
      break;
    case '/':
      sDrwLine(cc, 0, 2, 1, 0);
      width = 2;
      break;
    case '.':
      sDrwLine(cc, 0, 2, 0, 2);
      width = 2;
      break;
    case ',':
      sDrwLine(cc, 0, 2, 0, 3);
      width = 2;
      break;
    case '_':
      sDrwLine(cc, 0, 2, 1, 2);
      width = 2;
      break;
    case ':':
      sDrwLine(cc, 1.0/2.0, 1.0/2.0, 1.0/2.0+0.33, 1.0/2.0+0.1);
      sDrwLine(cc, 1.0/2.0, 3.0/2.0, 1.0/2.0+0.33, 3.0/2.0+0.1);
      width = 2;
      break;
      }

  // Advance character position
  sCX = sCX + (width+1)*sScale;
  } 


//
// Draw string s in given context cc
//
// [Using global character and scroll positions (sCX/sCY), (sX/sY)]
// 
function sDrwString(cc, s) {
  var i = 0;

  sCX=sX;
  sCY=sY;

  for (i=0; i<s.length; i++) {
    sDrwChar(cc, s.substr(i,1));
    }
  }


//
// Main scroll loop
//
// Draw scrolltext into double buffer and copy to screen canvas every (global) sDelay milliseconds
//
// [Using global screen canvas sC and context sCC, double buffer context sBC, scroll position sX]
// [Using global wrap marker sWrap and global handle sTimeout as well as timing variable sDelay]
// [Using global scroll text variable sText]
//
function sDrwScroll() {
  var cf = Math.floor(Math.random()*64);	// Colour fluctuations...

  clearTimeout(sTimeout);

  // Clear double buffer
  sBC.fillRect(0, 0, sC.width, sC.height);

  // Scroll one unit to left
  sX-=1;

  // Wrap?
  if (sX<sWrap) sX = sC.width+16;

  // Slowly change colour
  if (Math.floor(sX)%11==0) sBC.strokeStyle = "rgb("+(120+cf)+","+(120+cf)+","+(160+cf)+")";

  // Draw text into double buffer
  sDrwString(sBC, sText);

  // Copy buffer to screen
  sCC.drawImage(sB, 0, 0);

  sTimeout = setTimeout("sDrwScroll()", sDelay);
  }


// Initialise backgrounds, line/fill colour and width
sBC.strokeStyle = "rgb(120,120,160)";
sBC.fillStyle = "rgb(255,255,255)";
sC.style.background = "#FFFFFF";
sB.style.background = "#FFFFFF";
sBC.lineWidth = 1.22;

// Start scrolling
sTimeout = setTimeout("sDrwScroll()", sDelay); 

} // end HTML5 support

else { function letsHearIt() { document.mlMainAni.src="./MAIN_ANI.GIF"; } }	// Dummy function for older browsers

} // end element support