torque/examples/contour.html
2015-08-26 17:37:16 +02:00

315 lines
10 KiB
HTML

<!DOCTYPE html>
<meta charset="utf-8">
<body>
<canvas id = "sample" width = "600" height = "600"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
<script type="text/javascript">
var tile = {"x":[96,64,160,64,48,192,16,80,112,16,64,176,80,64,32,176,16,144,176,176,112,128,224,16,16,176,16,0,64,160,128,160,208,80,192,0,80,16,192,128,208,160,128,192,32,112,144,112,80,32,80,112,32,80,112,80,32,144,112,144,32,80,32,176,112,208,32,96,192,144,160,144,208,144,0,112,224,160,16,0,208,128,48,0,176,96,96,48,48,64,96,48,96,48,96],"y":[176,192,208,160,176,208,224,32,48,64,144,224,208,128,96,240,112,208,160,192,208,208,240,192,240,144,80,160,208,160,176,192,240,128,240,240,144,48,192,224,192,240,16,160,176,16,224,224,240,224,192,176,16,160,240,224,160,240,160,192,80,176,240,208,192,224,112,208,224,128,176,144,176,112,224,144,208,224,176,208,208,96,64,32,176,112,144,144,112,176,192,160,160,240,240],"z":6,"coord":{"x":18,"y":24,"z":6},"timeCount":[95],"timeIndex":[0],"renderDataPos":[0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94],"renderData":[3,4,3,3,3,4,2,1,1,1,1,5,2,3,1,11,2,5,2,6,2,4,4,5,1,1,1,1,1,1,2,1,8,7,15,1,8,1,1,4,3,6,1,1,1,2,2,1,5,2,4,1,1,2,2,1,1,5,2,4,1,1,2,2,2,5,2,6,8,1,2,1,1,2,1,1,1,2,3,1,4,1,2,1,3,1,4,1,1,2,1,2,2,4,2],"maxDate":0};
var grid = gridData(tile);
var canvas = document.getElementById("sample");
var ctx = canvas.getContext("2d");
for (var y = 0; y < grid.length; y++){
for (var x = 0; x < grid[0].length; x++){
ctx.beginPath();
ctx.arc(20 + x*20, 20 + y*20, 3, 0, 2 * Math.PI, false);
var value = grid[y][x];
ctx.fillStyle = "rgb("+0+", "+value * 50+", "+value * 50+")";
if(value === 0) ctx.fillStyle = "red";
ctx.fill();
}
}
var cellsX = grid[0].length-1;
var cellsY = grid.length-1;
var contourValues = [0];
var lines = [];
for(var c = 0; c < contourValues.length; c++){
var pointsTraveled = new Set();
var pointerX = 0, pointerY = 0, x = 0, y = 0;
var line = [];
var xy = march(0,0);
while(xy){
xy = march(xy.x, xy.y);
}
function march(x,y){
if(x >= grid[0].length){
pointerX = 0;
pointerY++;
return {x: pointerX, y: pointerY };
}
if (pointerX === 0 && y > grid.length-2) return;
if (pointsTraveled.has(x+":"+y) && line.length === 0){
pointerX ++;
return {x: pointerX, y: pointerY };
}
else{
pointsTraveled.add(x+":"+y);
var NW = grid[y][x],
NE = grid[y][x+1],
SE = grid[y+1]? grid[y+1][x+1]: 0,
SW = grid[y+1]? grid[y+1][x]: 0
var cornerValues = [NW, NE, SE, SW];
var currentPos = {x: x, y: y};
var previousPos = line.length > 0? {x: line[line.length-1].coord.x, y: line[line.length-1].coord.y}: null;
var next = getNext(currentPos, previousPos, cornerValues, contourValues[c]);
if (next){
if (line.length > 0 && (line[0].coord.x === x && line[0].coord.y === y)){
lines.push(line);
line = [];
pointerX ++;
return {x: pointerX, y: pointerY };
}
else{
line.push({coord: {x: x, y: y, interpolation: next.interpolation}, values: cornerValues});
return next;
}
}
else {
pointerX ++;
return {x: pointerX, y: pointerY };
}
}
}
}
ctx.strokeStyle = "black"
for (var l = 0; l < lines.length; l++){
var line = cardinalSpline(lines[l]);
ctx.beginPath();
ctx.moveTo(line[0][0], line[0][1]);
for (var p = 2; p < line.length; p+=2){
ctx.lineTo(line[p], line[p+1]);
}
ctx.closePath();
ctx.stroke();
}
function cardinalSpline(line){
var plainArray = [];
for (var p = 0; p < line.length; p++){
var interpolation = line[p].coord.interpolation || {x: 0.5, y: 0.5};
plainArray.push(20 + 20*line[p].coord.x + 20 * interpolation.x);
plainArray.push(20 + 20*line[p].coord.y + 20 * interpolation.y);
}
return cSpline(plainArray, 0.5, 25, true);
}
function gridData(tile){
var res = 16;
var grid = new Array(256/res);
for(var i =0; i<grid.length; i ++){
grid[i] = new Array(256/res);
for(var j =0; j < grid[i].length; j++){
grid[i][j] = 0;
}
}
for(var i =0; i < tile.renderData.length; i++){
var x = tile.x[i], y = tile.y[i];
grid[y/res][x/res] = tile.renderData[i];
}
return grid;
}
function getNext(currentPos, previousPos, cornerValues, contourValue){
var binaryCell = cornerValues.map(function(cornerValue){
if (cornerValue > contourValue){
return "1";
}
return "0";
}).join("");
var type = parseInt(binaryCell, 2);
var N = [0, -1],
S = [0, 1],
E = [1, 0],
W = [-1, 0];
var next, interpolation;
if (type === 0 || type === 15) return null;
else if (type === 1 || type === 14){
next = [S,W];
interpolation = {
x: lerp(cornerValues[2], cornerValues[3], contourValue),
y: lerp(cornerValues[0], cornerValues[3], contourValue)
};
}
else if (type === 2 || type === 13){
next = [E,S];
interpolation = {
x: lerp(cornerValues[3], cornerValues[2], contourValue),
y: lerp(cornerValues[1], cornerValues[2], contourValue)
};
}
else if (type === 3 || type === 12) {
next = [E,W];
interpolation = {
x: 0.5,
y: 0.5
};
}
else if (type === 4 || type === 11){
next = [N,E];
interpolation = {
x: lerp(cornerValues[0], cornerValues[1], contourValue),
y: lerp(cornerValues[2], cornerValues[1], contourValue)
};
}
else if (type === 6 || type === 9) {
next = [N,S];
interpolation = {
x: 0.5,
y: 0.5
};
}
else if (type === 7 || type === 8) {
next = [N,W];
interpolation = {
x: lerp(cornerValues[1], cornerValues[0], contourValue),
y: lerp(cornerValues[3], cornerValues[0], contourValue)
};
}
else if (type === 5 || type === 10) {
var diff = [previousPos.x - currentPos.x, previousPos.y - currentPos.y];
if (diff[0] === -1){
return {
x: currentPos.x,
y: currentPos.y - 1,
interpolation: {
x: lerp(cornerValues[1], cornerValues[0], contourValue),
y: lerp(cornerValues[3], cornerValues[0], contourValue)
}
};
} else if (diff[0] === 1){
return {
x: currentPos.x,
y: currentPos.y + 1,
interpolation: {
x: lerp(cornerValues[3], cornerValues[2], contourValue),
y: lerp(cornerValues[1], cornerValues[2], contourValue)
}
};
} else if (diff[1] === -1){
return {
x: currentPos.x + 1,
y: currentPos.y,
interpolation: {
x: lerp(cornerValues[1], cornerValues[0], contourValue),
y: lerp(cornerValues[3], cornerValues[0], contourValue)
}
};
} else if (diff[1] === 1){
return {
x: currentPos.x - 1,
y: currentPos.y,
interpolation: {
x: lerp(cornerValues[3], cornerValues[2], contourValue),
y: lerp(cornerValues[1], cornerValues[2], contourValue)
}
};
}
}
if (!previousPos || (currentPos.x + next[0][0] === previousPos.x && currentPos.y + next[0][1] === previousPos.y)){
return {x: currentPos.x + next[1][0], y: currentPos.y + next[1][1], interpolation};
}
else return {x: currentPos.x + next[0][0], y: currentPos.y + next[0][1], interpolation};
}
// Linear interpolation
function lerp(valueA, valueB, contourValue){
return Math.max(Math.min(1 + (-0.5) * (contourValue - valueA) / (valueB - valueA), 0.8), 0.2);
}
function cSpline(points, tension, numOfSeg, close) {
tension = (typeof tension === 'number') ? tension : 0.5;
numOfSeg = numOfSeg ? numOfSeg : 25;
var pts; // for cloning point array
var i = 1;
var l = points.length;
var rPos = 0;
var rLen = (l - 2) * numOfSeg + 2 + (close ? 2 * numOfSeg : 0);
var res = new Float32Array(rLen);
var cache = new Float32Array((numOfSeg + 2) * 4);
var cachePtr = 4;
var st, st2, st3, st23, st32, parse;
pts = points.slice(0);
if (close) {
pts.unshift(points[l - 1]); // insert end point as first point
pts.unshift(points[l - 2]);
pts.push(points[0], points[1]); // first point as last point
} else {
pts.unshift(points[1]); // copy 1. point and insert at beginning
pts.unshift(points[0]);
pts.push(points[l - 2], points[l - 1]); // duplicate end-points
}
// cache inner-loop calculations as they are based on t alone
cache[0] = 1; // 1,0,0,0
for (; i < numOfSeg; i++) {
st = i / numOfSeg;
st2 = st * st;
st3 = st2 * st;
st23 = st3 * 2;
st32 = st2 * 3;
cache[cachePtr++] = st23 - st32 + 1; // c1
cache[cachePtr++] = st32 - st23; // c2
cache[cachePtr++] = st3 - 2 * st2 + st; // c3
cache[cachePtr++] = st3 - st2; // c4
}
cache[++cachePtr] = 1; // 0,1,0,0
parse = function (pts, cache, l) {
var i = 2;
var t, pt1, pt2, pt3, pt4, t1x, t1y, t2x, t2y, c, c1, c2, c3, c4;
for (i; i < l; i += 2) {
pt1 = pts[i];
pt2 = pts[i + 1];
pt3 = pts[i + 2];
pt4 = pts[i + 3];
t1x = (pt3 - pts[i - 2]) * tension;
t1y = (pt4 - pts[i - 1]) * tension;
t2x = (pts[i + 4] - pt1) * tension;
t2y = (pts[i + 5] - pt2) * tension;
for (t = 0; t < numOfSeg; t++) {
//t * 4;
c = t << 2; //jshint ignore: line
c1 = cache[c];
c2 = cache[c + 1];
c3 = cache[c + 2];
c4 = cache[c + 3];
res[rPos++] = c1 * pt1 + c2 * pt3 + c3 * t1x + c4 * t2x;
res[rPos++] = c1 * pt2 + c2 * pt4 + c3 * t1y + c4 * t2y;
}
}
};
// calc. points
parse(pts, cache, l);
if (close) {
//l = points.length;
pts = [];
pts.push(points[l - 4], points[l - 3], points[l - 2], points[l - 1]); // second last and last
pts.push(points[0], points[1], points[2], points[3]); // first and second
parse(pts, cache, 4);
}
// add last point
l = close ? 0 : points.length - 2;
res[rPos++] = points[l];
res[rPos] = points[l + 1];
return res;
};
</script>