情人节专属纯js脚本1k大小的3D玫瑰效果_javascript技巧

with(m=Math)C=cos,S=sin,P=pow,R=random;c.width=c.height=f=500;h=-250;function p(a,b,c){if(c>60)return[S(a*7)*(13+5/(.2+P(b*4,4)))-S(b)*50,b*f+50,625+C(a*7)*(13+5/(.2+P(b*4,4)))+b*400,a*1-b/2,a];A=a*2-1;B=b*2-1;if(A*A+B*B<1){if(c>37){n=(j=c&1)?6:4;o=.5/(a+.01)+C(b*125)*3-a*300;w=b*h;return[o*C(n)+w*S(n)+j*610-390,o*S(n)-w*C(n)+550-j*350,1180+C(B+A)*99-j*300,.4-a*.1+P(1-B*B,-h*6)*.15-a*b*.4+C(a+b)/5+P(C((o*(a+1)+(B>0?w:-w))/25),30)*.1*(1-B*B),o/1e3+.7-o*w*3e-6]}if(c>32){c=c*1.16-.15;o=a*45-20;w=b*b*h;z=o*S(c)+w*C(c)+620;return[o*C(c)-w*S(c),28+C(B*.5)*99-b*b*b*60-z/2-h,z,(b*b*.3+P((1-(A*A)),7)*.15+.3)*b,b*.7]}o=A*(2-b)*(80-c*2);w=99-C(A)*120-C(b)*(-h-c*4.9)+C(P(1-b,7))*50+c*2;z=o*S(c)+w*C(c)+700;return[o*C(c)-w*S(c),B*99-C(P(b, 7))*50-c/3-z/1.35+450,z,(1-b/1.2)*.9+a*.1, P((1-b),20)/4+.05]}}setInterval('for(i=0;i<1e4;i++)if(s=p(R(),R(),i%46/.74)){z=s[2];x=~~(s[0]*f/z-h);y=~~(s[1]*f/z-h);if(!m[q=y*f+x]|m[q]>z)m[q]=z,a.fillStyle="rgb("+~(s[3]*h)+","+~(s[4]*h)+","+~(s[3]*s[3]*-80)+")",a.fillRect(x,y,1,1)}',0)

function surface(a, b) { // I'm using a and b as parameters ranging from 0 to 1.

return {

x: a*50,

y: b*50

};

// this surface will be a square of 50x50 units of size

}

var canvas = document.body.appendChild(document.createElement("canvas")),

cOntext= canvas.getContext("2d"),

a, b, position;

// Now I'm going to sample the surface at .1 intervals for a and b parameters:

for (a = 0; a <1; a += .1) {

for (b = 0; b <1; b += .1) {

position = surface(a, b);

context.fillRect(position.x, position.y, 1, 1);

}

}

function surface(a, b) {

var x = a * 100,

y = b * 100,

radius = 50,

x0 = 50,

y0 = 50;

if ((x - x0) * (x - x0) + (y - y0) * (y - y0)

// inside the circle

return {

x: x,

y: y

};

} else {

// outside the circle

return null;

}

}

if (position = surface(a, b)) {

context.fillRect(position.x, position.y, 1, 1);

}

function surface(a, b) {

// Circle using polar coordinates

var angle = a * Math.PI * 2,

radius = 50,

x0 = 50,

y0 = 50;

return {

x: Math.cos(angle) * radius * b + x0,

y: Math.sin(angle) * radius * b + y0

};

}

function surface(a, b) {

var x = a * 100,

y = b * 100,

radius = 50,

x0 = 50,

y0 = 50;

if ((x - x0) * (x - x0) + (y - y0) * (y - y0)

return {

x: x,

y: y * (1 + b) / 2 // deformation

};

} else {

return null;

}

}

function surface(a, b) {

var x = a * 100,

y = b * 100,

radius = 50,

x0 = 50,

y0 = 50;

if ((x - x0) * (x - x0) + (y - y0) * (y - y0)

return {

x: x,

y: y * (1 + b) / 2,

r: 100 + Math.floor((1 - b) * 155), // this will add a gradient

g: 50,

b: 50

};

} else {

return null;

}

}

for (a = 0; a <1; a += .01) {

for (b = 0; b <1; b += .001) {

if (point = surface(a, b)) {

context.fillStyle = "rgb(" + point.r + "," + point.g + "," + point.b + ")";

context.fillRect(point.x, point.y, 1, 1);

}

}

}

function surface(a, b) {

var angle = a * Math.PI * 2,

radius = 100,

length = 400;

return {

x: Math.cos(angle) * radius,

y: Math.sin(angle) * radius,

z: b * length - length / 2, // by subtracting length/2 I have centered the tube at (0, 0, 0)

r: 0,

g: Math.floor(b * 255),

b: 0

};

}

var pX, pY, // projected on canvas x and y coordinates

perspective = 350,

halfHeight = canvas.height / 2,

halfWidth = canvas.width / 2,

cameraZ = -700;

for (a = 0; a <1; a += .001) {

for (b = 0; b <1; b += .01) {

if (point = surface(a, b)) {

pX = (point.x * perspective) / (point.z - cameraZ) + halfWidth;

pY = (point.y * perspective) / (point.z - cameraZ) + halfHeight;

context.fillStyle = "rgb(" + point.r + "," + point.g + "," + point.b + ")";

context.fillRect(pX, pY, 1, 1);

}

}

}

var zBuffer = [],

zBufferIndex;

for (a = 0; a <1; a += .001) {

for (b = 0; b <1; b += .01) {

if (point = surface(a, b)) {

pX = Math.floor((point.x * perspective) / (point.z - cameraZ) + halfWidth);

pY = Math.floor((point.y * perspective) / (point.z - cameraZ) + halfHeight);

zBufferIndex = pY * canvas.width + pX;

if ((typeof zBuffer[zBufferIndex] === "undefined") || (point.z

zBuffer[zBufferIndex] = point.z;

context.fillStyle = "rgb(" + point.r + "," + point.g + "," + point.b + ")";

context.fillRect(pX, pY, 1, 1);

}

}

}

}

function surface(a, b) {

var angle = a * Math.PI * 2,

radius = 100,

length = 400,

x = Math.cos(angle) * radius,

y = Math.sin(angle) * radius,

z = b * length - length / 2,

yAxisRotatiOnAngle= -.4, // in radians!

rotatedX = x * Math.cos(yAxisRotationAngle) + z * Math.sin(yAxisRotationAngle),

rotatedZ = x * -Math.sin(yAxisRotationAngle) + z * Math.cos(yAxisRotationAngle);

return {

x: rotatedX,

y: y,

z: rotatedZ,

r: 0,

g: Math.floor(b * 255),

b: 0

};

}

var i;

window.setInterval(function () {

for (i = 0; i <10000; i++) {

if (point = surface(Math.random(), Math.random())) {

pX = Math.floor((point.x * perspective) / (point.z - cameraZ) + halfWidth);

pY = Math.floor((point.y * perspective) / (point.z - cameraZ) + halfHeight);

zBufferIndex = pY * canvas.width + pX;

if ((typeof zBuffer[zBufferIndex] === "undefined") || (point.z

zBuffer[zBufferIndex] = point.z;

context.fillStyle = "rgb(" + point.r + "," + point.g + "," + point.b + ")";

context.fillRect(pX, pY, 1, 1);

}

}

}

}, 0);