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Here are some 3D graphics made with just JavaScript, let teach yourself by this advance JavaScript code & tutorial. We have a TIE fighter rotating, and moving left and right; we may change axises, drawing modes, viewing styles and scenes.

Label: 3D graphics, TIE fighter, 3D Graphics Animation, 3D Animation in JavaScript

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<script type="text/javascript" from="JavaScriptBank.com">
/*
     This script downloaded from www.JavaScriptBank.com
     Come to view and download over 2000+ free javascript at www.JavaScriptBank.com
*/
/*************************************
 * Copyright 2006 Christopher Thomas *
 * You are free to redistribute this *
 *  code, in modified or unmodified  *
 * form, so long as you retain this  *
 *          copyright notice.        *
 *************************************/

/******************************************************************************
 * Due to the performance issues of painting pixels, I had to create a custom *
 * z-buffering algorithm that works on pixel ranges rather than individual    *
 * pixels to reduce the number of canvas draw calls.  It might be             *
 * patentable... though I doubt it is worth anything nowadays due to the      *
 * relative costs of operations of modern hardware (and even most software    *
 * framebuffers).                                                             *
 ******************************************************************************/

var canvas;
var ctx;

var FULL_WIDTH = 800;
var FULL_HEIGHT = 600;

var WIDTH = 800;
var HEIGHT = 600;

var avgRenderTime = 0;

// x, y, z

var vert1 = [[-1,-1,-1,1], [-1,1,-1,1], [1,1,-1,1], [1, -1, -1,1],
	    [-1,-1,1,1], [-1,1,1,1], [1,1,1,1], [1, -1, 1,1]];
var tri1 = [[0, 1, 2, "rgb(255,0,0)"], [2, 3, 0, "rgb(255,0,0)"],
	   [4, 6, 5, "rgb(0,255,0)"], [6, 4, 7, "rgb(0,255,0)"],
	   [0, 5, 1, "rgb(0,0,255)"], [0, 4, 5, "rgb(0,0,255)"],
	   [3, 2, 7, "rgb(0,255,255)"], [2, 6, 7, "rgb(0,255,255)"],
	   [0, 3, 4, "rgb(255,255,0)"], [3, 7, 4, "rgb(255,255,0)"],
	   [1, 6, 2, "rgb(255,0,255)"], [1, 5, 6, "rgb(255,0,255)"]];

var vert2 = [[-1, -1.5, .51, 1], [-1, 1.5, -.51, 1], [0, -1.5, .51, 1],
	    [-1, .5, .51, 1], [2, 1.5, -.2, 1], [-2, 1.5, .51, 1],
	    [1, 1.5, .51, 1], [2, 1.5, .51, 1], [-1, -1.5, -.51, 1]];

var tri2 = [[0, 1, 2, "rgb(255,0,0)"],
	    [3, 5, 4, "rgb(0,255,0)"],
	    [6, 7, 8, "rgb(0,0,255)"]];

var vert3 = [[.866, 0, .5, 1], [.5, .866, .5, 1], [0, 0, .5, 1],
	     [.5, .866, .5, 1], [-.5, .866, .5, 1], [0, 0, .5, 1],
	     [-.5, .866, .5, 1], [-.866, 0, .5, 1], [0, 0, .5, 1],
	     [-.866, .5, .5, 1], [-.866, -.5, .5, 1], [0, 0, .5, 1],
	     [-.866, 0, .5, 1], [-.5, -.866, .5, 1], [0, 0, .5, 1],
	     [-.5, -.866, .5, 1], [.5, -.866, .5, 1], [0, 0, .5, 1],
	     [.5, -.866, .5, 1], [.866, 0, .5, 1], [0, 0, .5, 1],
	     [.866, -.5, .5, 1], [.866, .5, .5, 1], [0, 0, .5, 1],

	     [.866, 0, -.5, 1], [.5, .866, -.5, 1], [0, 0, -.5, 1],
	     [.5, .866, -.5, 1], [-.5, .866, -.5, 1], [0, 0, -.5, 1],
	     [-.5, .866, -.5, 1], [-.866, 0, -.5, 1], [0, 0, -.5, 1],
	     [-.866, .5, -.5, 1], [-.866, -.5, -.5, 1], [0, 0, -.5, 1],
	     [-.866, 0, -.5, 1], [-.5, -.866, -.5, 1], [0, 0, -.5, 1],
	     [-.5, -.866, -.5, 1], [.5, -.866, -.5, 1], [0, 0, -.5, 1],
	     [.5, -.866, -.5, 1], [.866, 0, -.5, 1], [0, 0, -.5, 1],
	     [.866, -.5, -.5, 1], [.866, .5, -.5, 1], [0, 0, -.5, 1],

	     [.25, 0, 0, 1], [0, .25, 0, 1], [.0, 0, -.5, 1],
	     [.25, 0, 0, 1], [0, -.25, 0, 1], [.0, 0, -.5, 1],
	     [-.25, 0, 0, 1], [0, .25, 0, 1], [.0, 0, -.5, 1],
	     [-.25, 0, 0, 1], [0, -.25, 0, 1], [.0, 0, -.5, 1],

	     [.25, 0, 0, 1], [0, .25, 0, 1], [.0, 0, .5, 1],
	     [.25, 0, 0, 1], [0, -.25, 0, 1], [.0, 0, .5, 1],
	     [-.25, 0, 0, 1], [0, .25, 0, 1], [.0, 0, .5, 1],
	     [-.25, 0, 0, 1], [0, -.25, 0, 1], [.0, 0, .5, 1],

];
// I did not properly order some of these triangles, so they're facing the wrong way
var tri3 = [[0, 1, 2, "rgb(64, 64, 64)"],
	    [3, 4, 5, "rgb(64, 64, 64)"],
	    [6, 7, 8, "rgb(64, 64, 64)"],
	    //	    [9, 10, 11, "rgb(64, 64, 64)"],
	    [12, 13, 14, "rgb(64, 64, 64)"],
	    [15, 16, 17, "rgb(64, 64, 64)"],
	    [18, 19, 20, "rgb(64, 64, 64)"],
	    //	    [21, 22, 23, "rgb(64, 64, 64)"],

	    [24, 25, 26, "rgb(64, 64, 64)"],
	    [27, 28, 29, "rgb(64, 64, 64)"],
	    [30, 31, 32, "rgb(64, 64, 64)"],
	    //	    [33, 34, 35, "rgb(64, 64, 64)"],
	    [36, 37, 38, "rgb(64, 64, 64)"],
	    [39, 40, 41, "rgb(64, 64, 64)"],
	    [42, 43, 44, "rgb(64, 64, 64)"],
	    //	    [45, 46, 47, "rgb(64, 64, 64)"],

	    [48, 49, 50, "rgb(128, 128, 128)"],
	    [51, 52, 53, "rgb(128, 128, 128)"],
	    [54, 55, 56, "rgb(128, 128, 128)"],
	    [57, 58, 59, "rgb(128, 128, 128)"],

	    [60, 61, 62, "rgb(128, 128, 128)"],
	    [63, 64, 65, "rgb(128, 128, 128)"],
	    [66, 67, 68, "rgb(128, 128, 128)"],
	    [69, 70, 71, "rgb(128, 128, 128)"]
];

var vert = vert3;
var tri = tri3;

var twosided = true;

var angle = 47.4;
var axis = "X";
var mode = "lines";

var lastPoint = null;
var fastLines = true;
var fill = false;
var scanLineInfo;
var zbuff;
var drawInterval;
var dumpZ = false;

function changeQuality(direction) {
  if (direction == "better" && WIDTH < FULL_WIDTH) {
    WIDTH *= 2; HEIGHT *= 2;
  }
  else if (direction == "worse" && FULL_WIDTH/WIDTH < 16){
    WIDTH /= 2; HEIGHT /= 2;
  }
  if (WIDTH < FULL_WIDTH) {
    document.getElementById("qUpButton").disabled = false;
  }
  else
    document.getElementById("qUpButton").disabled = true;
  if (FULL_WIDTH / WIDTH >= 16) {
    document.getElementById("qDownButton").disabled = true;
  }
  else
    document.getElementById("qDownButton").disabled = false;

  document.getElementById("qualitySpan").innerHTML = (WIDTH / FULL_WIDTH)*100 + "%";
}

function init() {
  canvas = document.getElementById("theCanvas");
  var error = false;
  try {
    ctx = canvas.getContext("2d");
  } catch(e) {
    document.getElementById("errorMsg").style.display="block"; error = true;
  };
  
  if (!error)
    drawInterval = setInterval(plot, 10);
}

function dist(a, b) {
  var da; var db; var dc;
  da = a[0] - b[0];
  db = a[1] - b[1];
  dc = a[2] - b[2];
  return Math.sqrt(da*da + db*db + dc*dc)
}

function min(a, b) {
  return (a < b) ? a : b;
}

function max(a, b) {
  return (a > b) ? a : b;
}

function bresenham(x2, y2, z2) {
  if (!lastPoint) {
    lastPoint = [x2, y2, z2];
    return; // first point, just set up start point
  }
  var x1 = lastPoint[0];
  var y1 = lastPoint[1];
  var z1 = lastPoint[2];
  lastPoint = [x2,y2,z2];
  var steep;
  var temp;
  steep = Math.abs(y2-y1) > Math.abs(x2-x1);
  if (steep) {
    temp = x1;
    x1 = y1;
    y1 = temp;
    temp = x2;
    x2 = y2;
    y2 = temp;
  }
  if (x1 > x2) {
    temp = x1;
    x1 = x2;
    x2 = temp;

    temp = y1;
    y1 = y2;
    y2 = temp;

    temp = z1;
    z1 = z2;
    z2 = temp;
  }
  var dx = x2 - x1;
  var dy = Math.abs(y2 - y1);
  var error = 0;
  var derror = dy / dx;
  var y = y1;
  var ystep;
  if (y1 < y2)
    ystep = 1;
  else
    ystep = -1;

  var x;
  var minx, maxx;
  var zA;
  var zB;
  for (x=x1; x<=x2; x++) {
    var dx = max(x2 - x1, .01);
    if (steep) {
      plotPixel(y, x);
      if (fill && x >= 0 && x < HEIGHT) {
	if (scanLineInfo[x]) {
	  minx = scanLineInfo[x][0];
	  maxx = scanLineInfo[x][1];
	  zA = scanLineInfo[x][2];
	  zB = scanLineInfo[x][3];
	}
	else {
	  minx = y;
	  maxx = y;
	  zA = (x-x1)/dx * (z2-z1) + z1;
	  zB = (x-x1)/dx * (z2-z1) + z1;
	}
	if (y < minx) {
	  minx = y;
	  zA = (x-x1)/dx * (z2-z1) + z1;
	}
	if (y > maxx) {
	  maxx = y;
	  zB = (x-x1)/dx * (z2-z1) + z1;
	}
	if (isNaN(zA) || isNaN(zB)) {
	  alert(x + " " + x1 + " " + dx + " " + z2 + " " + z1);
	  null[5] = 0;
	}
	scanLineInfo[x] = [minx, maxx, zA, zB];
      }
    }
    else {
      plotPixel(x, y);
      if (fill && y >= 0 && y < HEIGHT) {
	if (scanLineInfo[y]) {
	  minx = scanLineInfo[y][0];
	  maxx = scanLineInfo[y][1];
	  zA = scanLineInfo[y][2];
	  zB = scanLineInfo[y][3];
	}
	else {
	  minx = x;
	  maxx = x;
	  zA = (x-x1)/dx * (z2-z1) + z1;
	  zB = (x-x1)/dx * (z2-z1) + z1;
	}
	if (x < minx) {
	  minx = x;
	  zA = (x-x1)/dx * (z2-z1) + z1;
	}
	if (x > maxx) {
	  maxx = x;
	  zB = (x-x1)/dx * (z2-z1) + z1;
	}

	scanLineInfo[y] = [minx, maxx, zA, zB];
      }
    }
    error += derror;
    if (error > .5) {
      y += ystep;
      error--;
    }
  }
}

function plotPixel(x, y) {
  if (fill)
    return;
  ctx.fillRect(x, y, 1, 1);
}

function doVert(v, d, first) {
  var y1 = (v[1]*d) / (d + v[2]);
  var x1 = (v[0]*d) / (d + v[2]);
  var z1 = v[2];
  // center 0,0 on the screen
  y1 *= HEIGHT;
  x1 *= HEIGHT;
  y1 += HEIGHT/2;
  x1 += WIDTH/2;

  if (mode == "lines") {
    if (fastLines) {
      if (first)
	ctx.moveTo(x1, y1);
      else
	ctx.lineTo(x1, y1);
    }
    else {
      //bresenham(parseInt(x1), parseInt(y1), parseInt(z1));
      bresenham(parseInt(x1), parseInt(y1), z1);
    }
  }
  else  if (mode == "points") {
    ctx.fillRect(x1-1, y1-1, 2, 2);
  }
}

function transform(v, m) {
  var x2 = v[0] * m[0][0] + v[1]*m[0][1] + v[2]*m[0][2] + v[3]*m[0][3];
  var y2 = v[0] * m[1][0] + v[1]*m[1][1] + v[2]*m[1][2] + v[3]*m[1][3];
  var z2 = v[0] * m[2][0] + v[1]*m[2][1] + v[2]*m[2][2] + v[3]*m[2][3];
  var w2 = v[0] * m[3][0] + v[1]*m[3][1] + v[2]*m[3][2] + v[3]*m[3][3];
  var rv = [x2, y2, z2, w2];
  return rv;
}

function plot() {
  var start; var stop;
  try { // safari compatibility
    start = Date.now();
  } catch (e) {}
  angle += .05;
  //angle = 94.148; axis = "Y"; fastLines = false; fill = true; dumpZ = true;clearInterval(drawInterval);
  //angle = 94.149; axis = "Y"; fastLines = false; fill = true; dumpZ = true;clearInterval(drawInterval);
  //angle = 56.7; axis = "Y"; fastLines = false; fill = true; dumpZ = true;clearInterval(drawInterval);
  var xposition = 1.5 * Math.cos(1.05*angle);
  var yposition = 0;//Math.sin(2*angle);
  var aboutZ = (axis == "Z");
  var aboutX = (axis == "X");
  var i; var j;
  var matrix;
  ctx.save();
  ctx.scale(FULL_WIDTH/WIDTH, FULL_HEIGHT/HEIGHT);
  zbuff = []; // clear z buffer
  ctx.clearRect(0, 0, WIDTH, HEIGHT); // clear screen

  if (aboutZ) {
    matrix = [[Math.cos(angle), -Math.sin(angle), 0, xposition],
	      [Math.sin(angle),  Math.cos(angle), 0, yposition],
	      [0,                0,               1, +5],
	      [0,                0,               0, 1]];
  }
  else if (aboutX) {
    matrix = [[1,                0,                0,               xposition],
	      [0,                Math.cos(angle),  Math.sin(angle), yposition],
	      [0,                -Math.sin(angle), Math.cos(angle), +5],
	      [0,                0,                0,               1]];
  }
  else {
    matrix = [[Math.cos(angle), 0,                 -Math.sin(angle), xposition],
	      [0,               1,                 0,                yposition],
	      [Math.sin(angle), 0,                 Math.cos(angle), +5],
	      [0,               0,                 0,               1]];
  }
  for (i=0; i<tri.length; i++) {
    doTri(tri[i], matrix);
  }
  if (!fastLines && mode == "lines" && fill)
    drawFromZBuff();
  try { // safari compatibility
    stop = Date.now();
    avgRenderTime = (.9 * avgRenderTime) + (.1 * (stop - start));
    window.status = "Frame render took " + (stop-start) + " ms (frame rate: " + parseInt(100000/avgRenderTime)/100 + " fps)";
  } catch (e) { }
  ctx.restore();
}

function zForPoint(x, range, reason) {
  var x1; var x2;
  var z1; var z2;
  x1 = range[0];
  x2 = range[1];
  z1 = range[2];
  z2 = range[3];
  var dx = x2-x1;
  dx = max(dx, .001);
  var fraction = (x-x1) / dx;

  var rv = fraction * (z2-z1) + z1;
  if (isNaN(rv)) {
    clearInterval(drawInterval);
    alert("x: " + x + " from range " + range + "\n" +
	  "dx was " + dx + " with fraction " + fraction + "\n" +
	  "z1: " + z1 + " z2: " + z2 + "\n" + 
	  "requested by " + reason);
    null[5] = 0;
  }
  return rv;
}

function horizOverlap(z, scan) {
  var zx1; var zx2;
  var sx1; var sx2;
  zx1 = z[0]; zx2 = z[1];
  sx1 = scan[0]; sx2 = scan[1];
  if (zx1 >= sx2 || zx2 <= sx1)
    return false; // no overlap
  var minx, maxx, overlap;
  if (zx1 <= sx1 && zx2 >= sx2) {
    // we're smaller than zbuff
    overlap = "newSmaller";
  }
  else if (sx1 <= zx1 && sx2 >= zx2) {
    // we cover entire range
    overlap = "newBigger";
  }
  else
    overlap = "partial";

  minx = max(zx1, sx1);
  maxx = min(zx2, sx2);

  if (minx == maxx)
    return false; // they touch, or it's 0 width or something, so reject this

  return [minx, maxx, overlap];
}

function cross(n1, n2) {
  var x, y, z;
  x = n1[1]*n2[2] - n1[2]*n2[1];
  y = n1[2]*n2[0] - n1[0]*n2[2];
  z = n1[0]*n2[1] - n1[1]*n2[0];
  var w = 0;
  return [x, y, z, w];
}

function dot(v1, v2) {
  return v1[0]*v2[0] + v1[1]*v2[1] + v1[2]*v2[2];
}

function normalize(v) {
  var l = Math.sqrt(v[0]*v[0]+v[1]*v[1]+v[2]*v[2]+v[3]*v[3]);
  return [v[0]/l, v[1]/l, v[2]/l, v[3]/l];
}

function doTri(poly, matrix) {
  scanLineInfo = [];
  lastPoint = null;
  if (mode == "lines" && fastLines) {
    ctx.beginPath();
    ctx.lineJoin = "bevel";
    ctx.strokeStyle = "rgb(0,0,0)";
  }

  var str;
  if (dumpZ)
    str = document.getElementById("statusText2").innerHTML;
  for (j=0; j<3; j++) {
    var d = 1;
    var v = transform(vert[poly[j]], matrix);
    //clearInterval(2);
    //alert(v);
    doVert(v, d, j == 0);
    if (dumpZ)
      str += v.join(", ") + "<br>";
  }
  str += "&nbsp;<br>";
  if (dumpZ)
    document.getElementById("statusText2").innerHTML = str;

  doVert(transform(vert[poly[0]], matrix), d, false);
  if (mode == "lines" && fastLines)
    ctx.stroke();
  if (mode == "lines" && fill) {
    var v1 = vert[poly[0]];
    var v2 = vert[poly[1]];
    var v3 = vert[poly[2]];
    var n1 = [v2[0]-v1[0], v2[1]-v1[1], v2[2]-v1[2], 0];
    var n2 = [v3[0]-v1[0], v3[1]-v1[1], v3[2]-v1[2], 0];
    n1 = normalize(n1);
    n2 = normalize(n2);
    var norm = cross(n1, n2);
    norm = normalize(norm);
    norm = transform(norm, matrix);
    // don't show backfacing
    if (!twosided && dot(norm, [0, 0, -1]) < -.1)
      return;

    // lighting
    var lightVec = normalize([.25, -.2, -1, 0]);
    var scaleFactor = Math.abs(dot(norm, lightVec));
    var newColor = poly[3];
    
    newColor = newColor.replace(/.*\(/, "");
    newColor = newColor.replace(/\)/, "");
    newColor = newColor.split(/,/);
    scaleFactor = max(scaleFactor, .3);
    newColor = "rgb(" + parseInt(newColor[0]*scaleFactor) + "," +
                        parseInt(newColor[1]*scaleFactor) + "," +
                        parseInt(newColor[2]*scaleFactor) + ")";
    

    for (var i=0; i<HEIGHT; i++) {
      if (i == 563563)
	alert("Scanline " + i + "\n" + 
	      "before: " + zbuff[i]);
      // was there anything drawn to this row?
      if (scanLineInfo[i]) {
	// pull out the zbuffer array for this row
	var zbrow = zbuff[i];
	if (!zbrow) {
	  zbrow = [[0, WIDTH, 9999, 9999, "rgb(255,255,255)"]];
	}
	for (var j=0; j<zbrow.length; j++) {
	  if (i == 563563) {
	    alert("for poly " + poly + "\n" + 
		  "zbrow item " + j + "\n" +
		  "before: " + zbuff[i])
	  }
	    // is there horizontal overlap?
	  var range = horizOverlap(zbrow[j], scanLineInfo[i]);
	  if (range) {
	    var zbz1; var zbz2;
	    var mz1; var mz2;
	    zbz1 = zForPoint(range[0], zbrow[j], "z1");
	    zbz2 = zForPoint(range[1], zbrow[j], "z2");
	    mz1 = zForPoint(range[0], scanLineInfo[i], "s1");
	    mz2 = zForPoint(range[1], scanLineInfo[i], "s2");

	    if (zbz1 >= mz1 && zbz2 >= mz2)
	      {
		// over the entire overlap range, we're closer
		// set our material for this overlap range
		if (range[2] == "newSmaller") {
		  // split the range up into 3 pieces {z, us, z}
		  var newx1, newx2, newx3, newx4;
		  newx1 = zbrow[j][0];
		  newx2 = scanLineInfo[i][0];
		  newx3 = scanLineInfo[i][1];
		  newx4 = zbrow[j][1];
		  var oldMat = zbrow[j][4];
		  var oldz1 = zbrow[j][2];
		  var oldz2 = zbrow[j][3];

		  var addedCount = 0;
		  if (newx1 != newx2) {
		    zbrow.splice(j+1+addedCount, 0, [newx1, newx2, oldz1, zbz1, oldMat]);
		    addedCount++;
		  }
		  if (newx2 != newx3) {
		    zbrow.splice(j+1+addedCount, 0, [newx2, newx3, mz1, mz2, newColor]);
		    addedCount++;
		  }
		  if (newx3 != newx4) {
		    zbrow.splice(j+1+addedCount, 0, [newx3, newx4, zbz2, oldz2, oldMat]);
		    addedCount++;
		  }
		  zbrow.splice(j, 1);

		  j += 2; // skip the 2 we added
		}
		else if (range[2] == "newBigger") {
		  // leave the full range, but set it to our material and update the z values
		  zbrow[j][2] = mz1;
		  zbrow[j][3] = mz2;
		  zbrow[j][4] = newColor;
		}
		else {
		  // split the range into pieces, since we're not completely
		  // contained within the range or larger than it
		  if (zbrow[j][0] >= scanLineInfo[i][0]) {
		    // this poly is in the left half of the interval
		    // insert it, and move the start of original region right
		    if (i == 563563) {
		      var blahstr = "";
		      for (var blah = 0; blah < zbuff[i].length; blah++)
			blahstr += zbuff[i][blah] + "\n";
		      alert("left before\n" +
			    "j: " + j + "\n" + 
			    "zbrow[j]: " + zbrow[j] + "\n" + 
			    "scanLineInfo[i]: " + scanLineInfo[i] + "\n" +
			    "poly: " + poly + "\n" + 
			    "range: " + range + "\n" + 
			    "zbrow: " + blahstr);
		    }
		    zbrow[j][2] = zForPoint(scanLineInfo[i][1], zbrow[j], "lateCut");
		    zbrow[j][0] = range[1];//scanLineInfo[i][1];
		    if (i == 563563) alert("left mid: " + zbrow[j]);
		    var cutCount = (zbrow[j][0] == zbrow[j][1]) ? 1 : 0;
		    if (i == 563563 && cutCount == 1) alert("CUT!");
		    zbrow.splice(j, cutCount, [range[0], scanLineInfo[i][1], mz1, mz2, newColor]);
		    //if (confirm(zbrow))
		    //  null[5] = 0;
		    j++;
		    if (i == 563563) {
		      var blahstr = "";
		      for (var blah = 0; blah < zbuff[i].length; blah++)
			blahstr += zbuff[i][blah] + "\n";
		      alert("left after\n" +
			    "j: " + j + "\n" + 
			    "zbrow[j]: " + zbrow[j] + "\n" + 
			    "scanLineInfo[i]: " + scanLineInfo[i] + "\n" +
			    "range: " + range + "\n" +
			    "poly: " + poly + "\n" + 
			    "zbrow: " + blahstr);
		    }
		  }
		  // i don' understand why this test is <= instead of >=
		  else if (zbrow[j][1] <= scanLineInfo[i][1]) {
		    // this poly is in the right half of the interval
		    // make original region end early and add the poly after it
		    if (i == 563563) {
		      var blahstr = "";
		      for (var blah = 0; blah < zbuff[i].length; blah++)
			blahstr += zbuff[i][blah] + "\n";
		      alert("right before\n" +
			    "j: " + j + "\n" + 
			    "zbrow[j]: " + zbrow[j] + "\n" + 
			    "scanLineInfo[i]: " + scanLineInfo[i] + "\n" +
			    "poly: " + poly + "\n" + 
			    "range: " + range + "\n" +
			    "zbrow: " + blahstr);
		    }
		    // TODO can this be zbz1?
		    zbrow[j][3] = zForPoint(scanLineInfo[i][0], zbrow[j], "earlyCut");
		    zbrow[j][1] = range[0];
		    var cutCount = (zbrow[j][0] == zbrow[j][1]) ? 1 : 0;
		    zbrow.splice(j+1, cutCount,
				 [range[0], range[1], mz1, mz2, newColor]);
		    //if (confirm(zbrow))
		    //  null[5] = 0;
		    j++; // skip over new range	
		    if (i == 563563) {
		      var blahstr = "";
		      for (var blah = 0; blah < zbuff[i].length; blah++)
			blahstr += zbuff[i][blah] + "\n";
		      alert("right after\n" +
			    "j: " + j + "\n" + 
			    "cutCount: " + cutCount + "\n" +
			    "zbrow[j]: " + zbrow[j] + "\n" + 
			    "scanLineInfo[i]: " + scanLineInfo[i] + "\n" +
			    "range: " + range + "\n" +
			    "zbrow: " + blahstr);
		    }
		  }
		  else if (range[0] == range[1]) {
		    // HACK TODO FIXME!!!
		    // this range is 0px wide, so ignore it?
		    window.status = "ignored!";
		    if (i == 563563) alert("ignored");
		  }
		  else {
		    // wtf?
		    
		    clearInterval(drawInterval);
		    alert("wtf?");
		    alert("need to split :-(\n" + 
			  "range of overlap: " + range + "\n" + 
			  "z: " + zbrow[j] + "\n" + 
			  "poly: " + scanLineInfo[i] + "\n" +
			  "zbrow: " + zbrow);
		    null[5] = 0;
		  }
		}
	      }
	    else if (zbz1 <= mz1 && zbz2 <= mz2)
	      {
		// already something closer... do nothing
		if (i == 563563) alert("already something closer");
	      }
	    else
	      {
		// partially in front, partially behind
		var isect = findIntersection(range, mz1, mz2, zbz1, zbz2);
		if (i == 563563) {
		  alert("partially in front, partially behind - doing intersect!\n" +
			"range: " + range + "\n" + 
			"poly: " + scanLineInfo[i] + "\n" +
			"zb: " + zbrow[j] + "\n" + 
			"isect: " + isect + "\n" + 
			"j: " + j);
		}
		isect = parseInt(isect);
		var die = true;
		if (mz1 <= zbz1) {
		  // we're on the left of the range, so end result should be
		  // [existing] {[us] [existing]}
		  // where { } indicates range of overlap
		  if (i == 563563) {
		    var blahstr = "";
		    for (var blah = 0; blah < zbuff[i].length; blah++)
		      blahstr += zbuff[i][blah] + "\n";
		    alert("Partial Left Before: " + blahstr);
		  }

		  var newx1; var newx2; var newx3; var newx4;
		  newx1 = zbrow[j][0];
		  newx2 = range[0];
		  newx3 = isect;
		  newx4 = zbrow[j][1];

		  var oldz1 = zbrow[j][2];
		  var oldz2 = zbrow[j][3];
		  var oldMat = zbrow[j][4];

		  var addedCount = 0;
		  if (newx1 != newx2) {
		    zbrow.splice(j+1+addedCount, 0, [newx1, newx2, oldz1, zbz1, oldMat]);
		    addedCount++;
		  }
		  if (newx2 != newx3) {
		    zbrow.splice(j+1+addedCount, 0, [newx2, newx3, mz1, zForPoint(newx3, [range[0], range[1], mz1, mz2], "splitRegion"), newColor]);
		    addedCount++;
		  }
		  if (newx3 != newx4) {
		    zbrow.splice(j+1+addedCount, 0, [newx3, newx4, zForPoint(newx3, [range[0], range[1], zbz1, zbz2], "splitRegion"), oldz2, oldMat]);
		    addedCount++;
		  }
		  zbrow.splice(j, 1); // cut the existing one
		  die = false;
		}
		else if (mz2 <= zbz2) {
		  if (i == 563563) {
		    var blahstr = "";
		    for (var blah = 0; blah < zbrow.length; blah++)
		      blahstr += zbrow[blah] + "\n";
		    alert("Partial Right Before: " + blahstr + "\n" + 
			  "scanLine: " + scanLineInfo[i] + "\n" +
			  "zb: " + zbrow[j] + "\n" + 
			  "range: " + range + "\n");
		  }

		  var newx1, newx2, newx3, newx4;
		  newx1 = zbrow[j][0];
		  newx2 = isect;
		  newx3 = range[1];
		  newx4 = zbrow[j][1];
		  if (i == 563563) alert(newx1 + " " + newx2 + " " + newx3 + " " + newx4);

		  var oldz1 = zbrow[j][2];
		  var oldz2 = zbrow[j][3];
		  var oldMat = zbrow[j][4];

		  var addedCount = 0;
		  if (newx1 != newx2) {
		    zbrow.splice(j+1+addedCount, 0, [newx1, newx2, oldz1, zForPoint(isect, [range[0], range[1], zbz1, zbz2], "splitRegion"), oldMat]);
		    addedCount++;
		  }
		  if (newx2 != newx3) {
		    zbrow.splice(j+1+addedCount, 0, [newx2, newx3, zForPoint(isect, [range[0], range[1], mz1, mz2], "splitRegion"), mz2, newColor]);
		    addedCount++;
		  }
		  if (newx3 != newx4) {
		    zbrow.splice(j+1+addedCount, 0, [newx3, newx4, zbz2, oldz1, oldMat]);
		    addedCount++;
		  }
		  zbrow.splice(j, 1); // cut the existing one

		  if (i == 563563) {
		    var blahstr = "";
		    for (var blah = 0; blah < zbrow.length; blah++)
		      blahstr += zbrow[blah] + "\n";
		    alert("Partial Right After: " + blahstr);
		  }
		  die = false;
		}
		else {
		  alert("partial, strange!");
		}
		if (die) {
		  alert("partial :-(");
		  alert("range: " + range + "\n" +
			"zbrow: " + zbrow[j] + "\n" + 
			"poly: " + scanLineInfo[i] + "\n");
		  //			zbz1 + "->" + zbz2 + " vs " + mz1 + "->" + mz2);
		  clearInterval(drawInterval);
		  null[5] = 0;
		}
	      }
	  }
	  if (i == 563563 && zbuff[i]) {
	    var blahstr = "";
	    for (var blah = 0; blah < zbuff[i].length; blah++)
	      blahstr += zbuff[i][blah] + "\n";
	    alert("for poly " + poly + "\n" + 
		  "after item " + j + ": " + blahstr);
	  }
	}
	zbuff[i] = zbrow;

	if (i == 563563) {
	  var blahstr = "";
	  for (var blah = 0; blah < zbuff[i].length; blah++)
	    blahstr += zbuff[i][blah] + "\n";
	  alert("after: " + blahstr);
	}
      }
    }
  }
}

// return x coordinate of intersection point
function findIntersection(range, za1, za2, zb1, zb2) {
  var dx = range[1] - range[0];
  var dza = za2 - za1;
  var dzb = zb2 - zb1;
  var slopea = dza / dx;
  var slopeb = dzb / dx;
  var offseta = zForPoint(0, [range[0], range[1], za1, za2], "findIntersection");
  var offsetb = zForPoint(0, [range[0], range[1], zb1, zb2], "findIntersection");
  var rv = (offseta - offsetb) / (slopeb - slopea);
  return rv;
}

function drawFromZBuff() {
  var str;
  if (dumpZ)
    str = "<table>";
  var j;
  for (j=0; j<HEIGHT; j++) {
    var zbrow = zbuff[j];
    if (zbrow) {
      if (dumpZ)
	str += "<tr><td>"+j+"</td>";
      var i;
      for (i=0; i<zbrow.length; i++) {
	if (!dumpZ)
	  if (zbrow[i][4] == "rgb(255,255,255)") {
	    continue; // don't bother drawing white
	  }
	ctx.beginPath();
	ctx.strokeStyle = zbrow[i][4];
	ctx.moveTo(zbrow[i][0], j+.5);
	ctx.lineTo(zbrow[i][1], j+.5);
	ctx.stroke();

	if (dumpZ)
	  str += "<td>" + zbrow[i] + "</td>";
      }
      if (dumpZ)
	str += "</tr>";
    }
  }
  if (dumpZ) {
    str += "</table>";
    document.getElementById("statusText").innerHTML = str;
  }  
}
window.onload = init;
</script>

Copy All x2

<p>Rotation axis: <input name="axis" value="Z" onclick="axis='Z'" type="radio"> Z
      <input name="axis" value="Y" onclick="axis='Y';" type="radio"> Y
      <input name="axis" value="X" onclick="axis='X';" checked="checked" type="radio"> X</p>

    <p>Draw mode: <input name="drawStyle" value="lines" onclick="mode='lines'" checked="checked" type="radio"> Lines / Polygons
      <input name="drawStyle" value="points" onclick="mode='points'" type="radio"> Points</p>
    <p>View style: <input name="fastLines" value="fast" onclick="fastLines=true;fill=false;" checked="checked" type="radio"> Built in lines (fast) <input name="fastLines" value="slow" onclick="fastLines=false;fill=false;" type="radio"> Manual Bresenham <input name="fastLines" value="true2" onclick="fill=true; fastLines=false;" type="radio"> <b>Filled polygons</b></p>
    <p>Scene: <input name="scene" value="square" onclick="vert=vert1;tri=tri1;twosided=false;" type="radio"> Cube <input name="scene" value="tris" onclick="vert=vert2;tri=tri2;twosided=true;" type="radio"> Mutually-overlapping triangles <input name="scene" value="tie" onclick="vert=vert3;tri=tri3;twosided=true;" checked="checked" type="radio"> <b>TIE fighter</b></p>

    <p>Quality: <input id="qDownButton" value="Worse (faster)" onclick="changeQuality('worse')" type="button"> <input id="qUpButton" disabled="DISABLED" value="Better (slower)" onclick="changeQuality('better')" type="button"> <span id="qualitySpan">100%</span>
    </p><div id="errorMsg" style="border: 5px solid red; display: none; font-size: 14pt;">Your browser doesn't support a required feature (the <a href="http://www.google.com/search?q=html+canvas+tag&amp;start=0&amp;start=0&amp;ie=utf-8&amp;oe=utf-8&amp;client=mozilla&amp;rls=org.mozilla:en-US:unofficial">HTML Canvas tag</a>).  You could get a <a href="http://www.mozilla.org/projects/seamonkey">better browser</a> (or <a href="http://www.mozilla.com/">this one</a>, or, if you're on a Mac, Safari).</div>
    <canvas id="theCanvas" width="800" height="600" onmousemove="return;var y = event.clientY - document.getBoxObjectFor(document.getElementById('theCanvas')).y + document.body.scrollTop; var x = event.clientX - document.getBoxObjectFor(document.getElementById('theCanvas')).x + document.body.scrollLeft; window.status=x+', '+y;"></canvas>

    <div id="statusText2"></div>
    <div id="statusText"></div>

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11/06/2013
Christopher Thomas [more]
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Simple 3D Graphics Animation in JavaScript

0/5 0 votes / 4,796 previews / 0 comment 11/06/2013 Here are some 3D graphics made with just JavaScript, let teach yourself by this ...Simple 3D Graphics Animation in JavaScript - Simple 3D Graphics Animation in JavaScript

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