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2d-noise.js
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2d-noise.js
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function setupTriangleStrips()
{
var color = 4;
myObjects = [], triPoints = [];
for(var y=0; y<usableGridInt -1; y++)
{
for(var x=0; x<usableGridInt- 1; x++)
{
triPoints[0] = calculatedValues[x][y];
triPoints[1] = calculatedValues[x][y+1];
triPoints[2] = calculatedValues[x+1][y]
myObjects.push(new Triangle(triPoints, color));
triPoints[0] = calculatedValues[x+1][y];
triPoints[1] = calculatedValues[x][y+1]
triPoints[2] = calculatedValues[x+1][y+1];
myObjects.push(new Triangle(triPoints, color));
}
}
}
function perlinInit()
{
var vv =0;
for(y=0; y<gridSize; y++)
for(x=0; x<gridSize; x++)
{
if(rndInt(0,2)==1)
vv = rndFloat();
else
vv = 0;
gridOfValues[x][y] = rotateGradientVector( new Vector_2D(0,vv), rndInt(0, 359) );
}
perlinGrid();
}
var maxFrequency = 1, amplitude = 1;
function perlinGrid()
{
var xCount =0, yCount = 0;
//calculatedValues =[ ];
var pn, newX = moverPoint.x / objectScale, newY = moverPoint.y / objectScale ;
var newX =0, newY = 0;
for(var v=newY; v<newY+usableGrid ; v+=detail)
{
for(var u=newX; u<newX+usableGrid ; u+=detail)
{
pn=0;
for(var frequency=1; frequency<=maxFrequency; frequency*=2)
{
//pn = perlinNoise(u,v);
pn += perlinNoise(u*frequency, v *frequency) * (amplitude/frequency);
}
if(pn <=0) pn = 0;
calculatedValues[xCount][yCount] = new Point(parseFloat(u.toFixed(3)), parseFloat(pn.toFixed(5)), parseFloat(v.toFixed(3)));
xCount++;
}
xCount=0;
yCount++;
}
}
function perlinGridBasic()
{
calculatedValues =[];
var point, pn;
for(var v=0; v<gridSize -1 ; v+=detail)
for(var u=0; u<gridSize -1 ; u+=detail)
{
pn = perlinNoise(u, v);
if(pn <=0)
pn = 0;
point = new Point(u, pn, v, pn);
calculatedValues.push(point);
}
}
function colorAssigner(value)
{
var color =0;
//value /= objectScale;
//console.log(value);
if(value>.9 )
color = 7; //"white";
if(value>.7 && value<=.9)
color = 4;//"#DEB887"; // blurly wood
if(value>=.3 && value<=.7)
color = 2 ; // "green";
if(value>0 && value<.3)
color = 2; // "#FFD700"; // gold
if(value<=0)
color = 1; //"#00008B";
return color;
}
function perlinNoise(x, y)
{
var grad =[], direct = [], dot =[];
var X = Math.floor(x), Y = Math.floor(y) , x10, x20, P0 ;
var u = x-X, v = y-Y;
grad[0] = gridOfValues[X][Y];
grad[1] = gridOfValues[X+1][Y];
grad[2] = gridOfValues[X][Y+1];
grad[3] = gridOfValues[X+1][Y+1];
direct[0] = new Vector_2D(u*mag, v*mag);
direct[1] = new Vector_2D((u-1)*mag, v*mag);
direct[2] = new Vector_2D(u*mag, (v-1)*mag, );
direct[3] = new Vector_2D((u-1)*mag, (v-1)*mag);
for(a=0; a<4; a++)
{
// console.log(a); grad[a].show(); direct[a].show();
dot[a] = dotProduct_2D(grad[a], direct[a]);
}
fu = fade5t(u), fv = fade5t(v) ;
x10 = lerp2(dot[0], dot[1], fu);
x20 = lerp2(dot[2], dot[3], fu);
P0 = lerp2(x10, x20, fv);
return P0 / 2 + 0.5;
}