30、转载樱花飘落代码,无需添加图片,个人觉得很漂亮,收藏一下![通俗易懂]

30、转载樱花飘落代码,无需添加图片,个人觉得很漂亮,收藏一下![通俗易懂]<!DOCTYPEHTMLPUBLIC”-//W3C//DTDHTML4.0Transitional//EN”><HTML><HEAD><TITLE>NewDocument</TITLE><METANAME=”Generator”CONTENT=”EditPlus”><MET…

大家好,又见面了,我是你们的朋友全栈君。

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
<style>body {
padding:0;
margin:0;
overflow:hidden;
height: 600px;
}
canvas {
padding:0;
margin:0;
}
div.btnbg {
position:fixed;
left:0;
top:0;
}</style>
</HEAD>
<BODY>
<canvas id="sakura"></canvas>
<div class="btnbg">
</div>
<!-- sakura shader -->
<script id="sakura_point_vsh" type="x-shader/x_vertex">
uniform mat4 uProjection;
uniform mat4 uModelview;
uniform vec3 uResolution;
uniform vec3 uOffset;
uniform vec3 uDOF;  //x:focus distance, y:focus radius, z:max radius
uniform vec3 uFade; //x:start distance, y:half distance, z:near fade start
attribute vec3 aPosition;
attribute vec3 aEuler;
attribute vec2 aMisc; //x:size, y:fade
varying vec3 pposition;
varying float psize;
varying float palpha;
varying float pdist;
//varying mat3 rotMat;
varying vec3 normX;
varying vec3 normY;
varying vec3 normZ;
varying vec3 normal;
varying float diffuse;
varying float specular;
varying float rstop;
varying float distancefade;
void main(void) {
// Projection is based on vertical angle
vec4 pos = uModelview * vec4(aPosition + uOffset, 1.0);
gl_Position = uProjection * pos;
gl_PointSize = aMisc.x * uProjection[1][1] / -pos.z * uResolution.y * 0.5;
pposition = pos.xyz;
psize = aMisc.x;
pdist = length(pos.xyz);
palpha = smoothstep(0.0, 1.0, (pdist - 0.1) / uFade.z);
vec3 elrsn = sin(aEuler);
vec3 elrcs = cos(aEuler);
mat3 rotx = mat3(
1.0, 0.0, 0.0,
0.0, elrcs.x, elrsn.x,
0.0, -elrsn.x, elrcs.x
);
mat3 roty = mat3(
elrcs.y, 0.0, -elrsn.y,
0.0, 1.0, 0.0,
elrsn.y, 0.0, elrcs.y
);
mat3 rotz = mat3(
elrcs.z, elrsn.z, 0.0, 
-elrsn.z, elrcs.z, 0.0,
0.0, 0.0, 1.0
);
mat3 rotmat = rotx * roty * rotz;
normal = rotmat[2];
mat3 trrotm = mat3(
rotmat[0][0], rotmat[1][0], rotmat[2][0],
rotmat[0][1], rotmat[1][1], rotmat[2][1],
rotmat[0][2], rotmat[1][2], rotmat[2][2]
);
normX = trrotm[0];
normY = trrotm[1];
normZ = trrotm[2];
const vec3 lit = vec3(0.6917144638660746, 0.6917144638660746, -0.20751433915982237);
float tmpdfs = dot(lit, normal);
if(tmpdfs < 0.0) {
normal = -normal;
tmpdfs = dot(lit, normal);
}
diffuse = 0.4 + tmpdfs;
vec3 eyev = normalize(-pos.xyz);
if(dot(eyev, normal) > 0.0) {
vec3 hv = normalize(eyev + lit);
specular = pow(max(dot(hv, normal), 0.0), 20.0);
}
else {
specular = 0.0;
}
rstop = clamp((abs(pdist - uDOF.x) - uDOF.y) / uDOF.z, 0.0, 1.0);
rstop = pow(rstop, 0.5);
//-0.69315 = ln(0.5)
distancefade = min(1.0, exp((uFade.x - pdist) * 0.69315 / uFade.y));
}
</script>
<script id="sakura_point_fsh" type="x-shader/x_fragment">
#ifdef GL_ES
//precision mediump float;
precision highp float;
#endif
uniform vec3 uDOF;  //x:focus distance, y:focus radius, z:max radius
uniform vec3 uFade; //x:start distance, y:half distance, z:near fade start
const vec3 fadeCol = vec3(0.08, 0.03, 0.06);
varying vec3 pposition;
varying float psize;
varying float palpha;
varying float pdist;
//varying mat3 rotMat;
varying vec3 normX;
varying vec3 normY;
varying vec3 normZ;
varying vec3 normal;
varying float diffuse;
varying float specular;
varying float rstop;
varying float distancefade;
float ellipse(vec2 p, vec2 o, vec2 r) {
vec2 lp = (p - o) / r;
return length(lp) - 1.0;
}
void main(void) {
vec3 p = vec3(gl_PointCoord - vec2(0.5, 0.5), 0.0) * 2.0;
vec3 d = vec3(0.0, 0.0, -1.0);
float nd = normZ.z; //dot(-normZ, d);
if(abs(nd) < 0.0001) discard;
float np = dot(normZ, p);
vec3 tp = p + d * np / nd;
vec2 coord = vec2(dot(normX, tp), dot(normY, tp));
//angle = 15 degree
const float flwrsn = 0.258819045102521;
const float flwrcs = 0.965925826289068;
mat2 flwrm = mat2(flwrcs, -flwrsn, flwrsn, flwrcs);
vec2 flwrp = vec2(abs(coord.x), coord.y) * flwrm;
float r;
if(flwrp.x < 0.0) {
r = ellipse(flwrp, vec2(0.065, 0.024) * 0.5, vec2(0.36, 0.96) * 0.5);
}
else {
r = ellipse(flwrp, vec2(0.065, 0.024) * 0.5, vec2(0.58, 0.96) * 0.5);
}
if(r > rstop) discard;
vec3 col = mix(vec3(1.0, 0.8, 0.75), vec3(1.0, 0.9, 0.87), r);
float grady = mix(0.0, 1.0, pow(coord.y * 0.5 + 0.5, 0.35));
col *= vec3(1.0, grady, grady);
col *= mix(0.8, 1.0, pow(abs(coord.x), 0.3));
col = col * diffuse + specular;
col = mix(fadeCol, col, distancefade);
float alpha = (rstop > 0.001)? (0.5 - r / (rstop * 2.0)) : 1.0;
alpha = smoothstep(0.0, 1.0, alpha) * palpha;
gl_FragColor = vec4(col * 0.5, alpha);
}
</script>
<!-- effects -->
<script id="fx_common_vsh" type="x-shader/x_vertex">
uniform vec3 uResolution;
attribute vec2 aPosition;
varying vec2 texCoord;
varying vec2 screenCoord;
void main(void) {
gl_Position = vec4(aPosition, 0.0, 1.0);
texCoord = aPosition.xy * 0.5 + vec2(0.5, 0.5);
screenCoord = aPosition.xy * vec2(uResolution.z, 1.0);
}
</script>
<script id="bg_fsh" type="x-shader/x_fragment">
#ifdef GL_ES
//precision mediump float;
precision highp float;
#endif
uniform vec2 uTimes;
varying vec2 texCoord;
varying vec2 screenCoord;
void main(void) {
vec3 col;
float c;
vec2 tmpv = texCoord * vec2(0.8, 1.0) - vec2(0.95, 1.0);
c = exp(-pow(length(tmpv) * 1.8, 2.0));
col = mix(vec3(0.02, 0.0, 0.03), vec3(0.96, 0.98, 1.0) * 1.5, c);
gl_FragColor = vec4(col * 0.5, 1.0);
}
</script>
<script id="fx_brightbuf_fsh" type="x-shader/x_fragment">
#ifdef GL_ES
//precision mediump float;
precision highp float;
#endif
uniform sampler2D uSrc;
uniform vec2 uDelta;
varying vec2 texCoord;
varying vec2 screenCoord;
void main(void) {
vec4 col = texture2D(uSrc, texCoord);
gl_FragColor = vec4(col.rgb * 2.0 - vec3(0.5), 1.0);
}
</script>
<script id="fx_dirblur_r4_fsh" type="x-shader/x_fragment">
#ifdef GL_ES
//precision mediump float;
precision highp float;
#endif
uniform sampler2D uSrc;
uniform vec2 uDelta;
uniform vec4 uBlurDir; //dir(x, y), stride(z, w)
varying vec2 texCoord;
varying vec2 screenCoord;
void main(void) {
vec4 col = texture2D(uSrc, texCoord);
col = col + texture2D(uSrc, texCoord + uBlurDir.xy * uDelta);
col = col + texture2D(uSrc, texCoord - uBlurDir.xy * uDelta);
col = col + texture2D(uSrc, texCoord + (uBlurDir.xy + uBlurDir.zw) * uDelta);
col = col + texture2D(uSrc, texCoord - (uBlurDir.xy + uBlurDir.zw) * uDelta);
gl_FragColor = col / 5.0;
}
</script>
<!-- effect fragment shader template -->
<script id="fx_common_fsh" type="x-shader/x_fragment">
#ifdef GL_ES
//precision mediump float;
precision highp float;
#endif
uniform sampler2D uSrc;
uniform vec2 uDelta;
varying vec2 texCoord;
varying vec2 screenCoord;
void main(void) {
gl_FragColor = texture2D(uSrc, texCoord);
}
</script>
<!-- post processing -->
<script id="pp_final_vsh" type="x-shader/x_vertex">
uniform vec3 uResolution;
attribute vec2 aPosition;
varying vec2 texCoord;
varying vec2 screenCoord;
void main(void) {
gl_Position = vec4(aPosition, 0.0, 1.0);
texCoord = aPosition.xy * 0.5 + vec2(0.5, 0.5);
screenCoord = aPosition.xy * vec2(uResolution.z, 1.0);
}
</script>
<script id="pp_final_fsh" type="x-shader/x_fragment">
#ifdef GL_ES
//precision mediump float;
precision highp float;
#endif
uniform sampler2D uSrc;
uniform sampler2D uBloom;
uniform vec2 uDelta;
varying vec2 texCoord;
varying vec2 screenCoord;
void main(void) {
vec4 srccol = texture2D(uSrc, texCoord) * 2.0;
vec4 bloomcol = texture2D(uBloom, texCoord);
vec4 col;
col = srccol + bloomcol * (vec4(1.0) + srccol);
col *= smoothstep(1.0, 0.0, pow(length((texCoord - vec2(0.5)) * 2.0), 1.2) * 0.5);
col = pow(col, vec4(0.45454545454545)); //(1.0 / 2.2)
gl_FragColor = vec4(col.rgb, 1.0);
gl_FragColor.a = 1.0;
}
</script>
<script>
// Utilities
var Vector3 = {};
var Matrix44 = {};
Vector3.create = function(x, y, z) {
return {'x':x, 'y':y, 'z':z};
};
Vector3.dot = function (v0, v1) {
return v0.x * v1.x + v0.y * v1.y + v0.z * v1.z;
};
Vector3.cross = function (v, v0, v1) {
v.x = v0.y * v1.z - v0.z * v1.y;
v.y = v0.z * v1.x - v0.x * v1.z;
v.z = v0.x * v1.y - v0.y * v1.x;
};
Vector3.normalize = function (v) {
var l = v.x * v.x + v.y * v.y + v.z * v.z;
if(l > 0.00001) {
l = 1.0 / Math.sqrt(l);
v.x *= l;
v.y *= l;
v.z *= l;
}
};
Vector3.arrayForm = function(v) {
if(v.array) {
v.array[0] = v.x;
v.array[1] = v.y;
v.array[2] = v.z;
}
else {
v.array = new Float32Array([v.x, v.y, v.z]);
}
return v.array;
};
Matrix44.createIdentity = function () {
return new Float32Array([1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0]);
};
Matrix44.loadProjection = function (m, aspect, vdeg, near, far) {
var h = near * Math.tan(vdeg * Math.PI / 180.0 * 0.5) * 2.0;
var w = h * aspect;
m[0] = 2.0 * near / w;
m[1] = 0.0;
m[2] = 0.0;
m[3] = 0.0;
m[4] = 0.0;
m[5] = 2.0 * near / h;
m[6] = 0.0;
m[7] = 0.0;
m[8] = 0.0;
m[9] = 0.0;
m[10] = -(far + near) / (far - near);
m[11] = -1.0;
m[12] = 0.0;
m[13] = 0.0;
m[14] = -2.0 * far * near / (far - near);
m[15] = 0.0;
};
Matrix44.loadLookAt = function (m, vpos, vlook, vup) {
var frontv = Vector3.create(vpos.x - vlook.x, vpos.y - vlook.y, vpos.z - vlook.z);
Vector3.normalize(frontv);
var sidev = Vector3.create(1.0, 0.0, 0.0);
Vector3.cross(sidev, vup, frontv);
Vector3.normalize(sidev);
var topv = Vector3.create(1.0, 0.0, 0.0);
Vector3.cross(topv, frontv, sidev);
Vector3.normalize(topv);
m[0] = sidev.x;
m[1] = topv.x;
m[2] = frontv.x;
m[3] = 0.0;
m[4] = sidev.y;
m[5] = topv.y;
m[6] = frontv.y;
m[7] = 0.0;
m[8] = sidev.z;
m[9] = topv.z;
m[10] = frontv.z;
m[11] = 0.0;
m[12] = -(vpos.x * m[0] + vpos.y * m[4] + vpos.z * m[8]);
m[13] = -(vpos.x * m[1] + vpos.y * m[5] + vpos.z * m[9]);
m[14] = -(vpos.x * m[2] + vpos.y * m[6] + vpos.z * m[10]);
m[15] = 1.0;
};
//
var timeInfo = {
'start':0, 'prev':0, // Date
'delta':0, 'elapsed':0 // Number(sec)
};
//
var gl;
var renderSpec = {
'width':0,
'height':0,
'aspect':1,
'array':new Float32Array(3),
'halfWidth':0,
'halfHeight':0,
'halfArray':new Float32Array(3)
// and some render targets. see setViewport()
};
renderSpec.setSize = function(w, h) {
renderSpec.width = w;
renderSpec.height = h;
renderSpec.aspect = renderSpec.width / renderSpec.height;
renderSpec.array[0] = renderSpec.width;
renderSpec.array[1] = renderSpec.height;
renderSpec.array[2] = renderSpec.aspect;
renderSpec.halfWidth = Math.floor(w / 2);
renderSpec.halfHeight = Math.floor(h / 2);
renderSpec.halfArray[0] = renderSpec.halfWidth;
renderSpec.halfArray[1] = renderSpec.halfHeight;
renderSpec.halfArray[2] = renderSpec.halfWidth / renderSpec.halfHeight;
};
function deleteRenderTarget(rt) {
gl.deleteFramebuffer(rt.frameBuffer);
gl.deleteRenderbuffer(rt.renderBuffer);
gl.deleteTexture(rt.texture);
}
function createRenderTarget(w, h) {
var ret = {
'width':w,
'height':h,
'sizeArray':new Float32Array([w, h, w / h]),
'dtxArray':new Float32Array([1.0 / w, 1.0 / h])
};
ret.frameBuffer = gl.createFramebuffer();
ret.renderBuffer = gl.createRenderbuffer();
ret.texture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, ret.texture);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, w, h, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);
gl.bindFramebuffer(gl.FRAMEBUFFER, ret.frameBuffer);
gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, ret.texture, 0);
gl.bindRenderbuffer(gl.RENDERBUFFER, ret.renderBuffer);
gl.renderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_COMPONENT16, w, h);
gl.framebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT, gl.RENDERBUFFER, ret.renderBuffer);
gl.bindTexture(gl.TEXTURE_2D, null);
gl.bindRenderbuffer(gl.RENDERBUFFER, null);
gl.bindFramebuffer(gl.FRAMEBUFFER, null);
return ret;
}
function compileShader(shtype, shsrc) {
var retsh = gl.createShader(shtype);
gl.shaderSource(retsh, shsrc);
gl.compileShader(retsh);
if(!gl.getShaderParameter(retsh, gl.COMPILE_STATUS)) {
var errlog = gl.getShaderInfoLog(retsh);
gl.deleteShader(retsh);
console.error(errlog);
return null;
}
return retsh;
}
function createShader(vtxsrc, frgsrc, uniformlist, attrlist) {
var vsh = compileShader(gl.VERTEX_SHADER, vtxsrc);
var fsh = compileShader(gl.FRAGMENT_SHADER, frgsrc);
if(vsh == null || fsh == null) {
return null;
}
var prog = gl.createProgram();
gl.attachShader(prog, vsh);
gl.attachShader(prog, fsh);
gl.deleteShader(vsh);
gl.deleteShader(fsh);
gl.linkProgram(prog);
if (!gl.getProgramParameter(prog, gl.LINK_STATUS)) {
var errlog = gl.getProgramInfoLog(prog);
console.error(errlog);
return null;
}
if(uniformlist) {
prog.uniforms = {};
for(var i = 0; i < uniformlist.length; i++) {
prog.uniforms[uniformlist[i]] = gl.getUniformLocation(prog, uniformlist[i]);
}
}
if(attrlist) {
prog.attributes = {};
for(var i = 0; i < attrlist.length; i++) {
var attr = attrlist[i];
prog.attributes[attr] = gl.getAttribLocation(prog, attr);
}
}
return prog;
}
function useShader(prog) {
gl.useProgram(prog);
for(var attr in prog.attributes) {
gl.enableVertexAttribArray(prog.attributes[attr]);;
}
}
function unuseShader(prog) {
for(var attr in prog.attributes) {
gl.disableVertexAttribArray(prog.attributes[attr]);;
}
gl.useProgram(null);
}
var projection = {
'angle':60,
'nearfar':new Float32Array([0.1, 100.0]),
'matrix':Matrix44.createIdentity()
};
var camera = {
'position':Vector3.create(0, 0, 100),
'lookat':Vector3.create(0, 0, 0),
'up':Vector3.create(0, 1, 0),
'dof':Vector3.create(10.0, 4.0, 8.0),
'matrix':Matrix44.createIdentity()
};
var pointFlower = {};
var meshFlower = {};
var sceneStandBy = false;
var BlossomParticle = function () {
this.velocity = new Array(3);
this.rotation = new Array(3);
this.position = new Array(3);
this.euler = new Array(3);
this.size = 1.0;
this.alpha = 1.0;
this.zkey = 0.0;
};
BlossomParticle.prototype.setVelocity = function (vx, vy, vz) {
this.velocity[0] = vx;
this.velocity[1] = vy;
this.velocity[2] = vz;
};
BlossomParticle.prototype.setRotation = function (rx, ry, rz) {
this.rotation[0] = rx;
this.rotation[1] = ry;
this.rotation[2] = rz;
};
BlossomParticle.prototype.setPosition = function (nx, ny, nz) {
this.position[0] = nx;
this.position[1] = ny;
this.position[2] = nz;
};
BlossomParticle.prototype.setEulerAngles = function (rx, ry, rz) {
this.euler[0] = rx;
this.euler[1] = ry;
this.euler[2] = rz;
};
BlossomParticle.prototype.setSize = function (s) {
this.size = s;
};
BlossomParticle.prototype.update = function (dt, et) {
this.position[0] += this.velocity[0] * dt;
this.position[1] += this.velocity[1] * dt;
this.position[2] += this.velocity[2] * dt;
this.euler[0] += this.rotation[0] * dt;
this.euler[1] += this.rotation[1] * dt;
this.euler[2] += this.rotation[2] * dt;
};
function createPointFlowers() {
// get point sizes
var prm = gl.getParameter(gl.ALIASED_POINT_SIZE_RANGE);
renderSpec.pointSize = {'min':prm[0], 'max':prm[1]};
var vtxsrc = document.getElementById("sakura_point_vsh").textContent;
var frgsrc = document.getElementById("sakura_point_fsh").textContent;
pointFlower.program = createShader(
vtxsrc, frgsrc,
['uProjection', 'uModelview', 'uResolution', 'uOffset', 'uDOF', 'uFade'],
['aPosition', 'aEuler', 'aMisc']
);
useShader(pointFlower.program);
pointFlower.offset = new Float32Array([0.0, 0.0, 0.0]);
pointFlower.fader = Vector3.create(0.0, 10.0, 0.0);
// paramerters: velocity[3], rotate[3]
pointFlower.numFlowers = 1600;
pointFlower.particles = new Array(pointFlower.numFlowers);
// vertex attributes {position[3], euler_xyz[3], size[1]}
pointFlower.dataArray = new Float32Array(pointFlower.numFlowers * (3 + 3 + 2));
pointFlower.positionArrayOffset = 0;
pointFlower.eulerArrayOffset = pointFlower.numFlowers * 3;
pointFlower.miscArrayOffset = pointFlower.numFlowers * 6;
pointFlower.buffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, pointFlower.buffer);
gl.bufferData(gl.ARRAY_BUFFER, pointFlower.dataArray, gl.DYNAMIC_DRAW);
gl.bindBuffer(gl.ARRAY_BUFFER, null);
unuseShader(pointFlower.program);
for(var i = 0; i < pointFlower.numFlowers; i++) {
pointFlower.particles[i] = new BlossomParticle();
}
}
function initPointFlowers() {
//area
pointFlower.area = Vector3.create(20.0, 20.0, 20.0);
pointFlower.area.x = pointFlower.area.y * renderSpec.aspect;
pointFlower.fader.x = 10.0; //env fade start
pointFlower.fader.y = pointFlower.area.z; //env fade half
pointFlower.fader.z = 0.1;  //near fade start
//particles
var PI2 = Math.PI * 2.0;
var tmpv3 = Vector3.create(0, 0, 0);
var tmpv = 0;
var symmetryrand = function() {return (Math.random() * 2.0 - 1.0);};
for(var i = 0; i < pointFlower.numFlowers; i++) {
var tmpprtcl = pointFlower.particles[i];
//velocity
tmpv3.x = symmetryrand() * 0.3 + 0.8;
tmpv3.y = symmetryrand() * 0.2 - 1.0;
tmpv3.z = symmetryrand() * 0.3 + 0.5;
Vector3.normalize(tmpv3);
tmpv = 2.0 + Math.random() * 1.0;
tmpprtcl.setVelocity(tmpv3.x * tmpv, tmpv3.y * tmpv, tmpv3.z * tmpv);
//rotation
tmpprtcl.setRotation(
symmetryrand() * PI2 * 0.5,
symmetryrand() * PI2 * 0.5,
symmetryrand() * PI2 * 0.5
);
//position
tmpprtcl.setPosition(
symmetryrand() * pointFlower.area.x,
symmetryrand() * pointFlower.area.y,
symmetryrand() * pointFlower.area.z
);
//euler
tmpprtcl.setEulerAngles(
Math.random() * Math.PI * 2.0,
Math.random() * Math.PI * 2.0,
Math.random() * Math.PI * 2.0
);
//size
tmpprtcl.setSize(0.9 + Math.random() * 0.1);
}
}
function renderPointFlowers() {
//update
var PI2 = Math.PI * 2.0;
var limit = [pointFlower.area.x, pointFlower.area.y, pointFlower.area.z];
var repeatPos = function (prt, cmp, limit) {
if(Math.abs(prt.position[cmp]) - prt.size * 0.5 > limit) {
//out of area
if(prt.position[cmp] > 0) {
prt.position[cmp] -= limit * 2.0;
}
else {
prt.position[cmp] += limit * 2.0;
}
}
};
var repeatEuler = function (prt, cmp) {
prt.euler[cmp] = prt.euler[cmp] % PI2;
if(prt.euler[cmp] < 0.0) {
prt.euler[cmp] += PI2;
}
};
for(var i = 0; i < pointFlower.numFlowers; i++) {
var prtcl = pointFlower.particles[i];
prtcl.update(timeInfo.delta, timeInfo.elapsed);
repeatPos(prtcl, 0, pointFlower.area.x);
repeatPos(prtcl, 1, pointFlower.area.y);
repeatPos(prtcl, 2, pointFlower.area.z);
repeatEuler(prtcl, 0);
repeatEuler(prtcl, 1);
repeatEuler(prtcl, 2);
prtcl.alpha = 1.0;//(pointFlower.area.z - prtcl.position[2]) * 0.5;
prtcl.zkey = (camera.matrix[2] * prtcl.position[0]
+ camera.matrix[6] * prtcl.position[1]
+ camera.matrix[10] * prtcl.position[2]
+ camera.matrix[14]);
}
// sort
pointFlower.particles.sort(function(p0, p1){return p0.zkey - p1.zkey;});
// update data
var ipos = pointFlower.positionArrayOffset;
var ieuler = pointFlower.eulerArrayOffset;
var imisc = pointFlower.miscArrayOffset;
for(var i = 0; i < pointFlower.numFlowers; i++) {
var prtcl = pointFlower.particles[i];
pointFlower.dataArray[ipos] = prtcl.position[0];
pointFlower.dataArray[ipos + 1] = prtcl.position[1];
pointFlower.dataArray[ipos + 2] = prtcl.position[2];
ipos += 3;
pointFlower.dataArray[ieuler] = prtcl.euler[0];
pointFlower.dataArray[ieuler + 1] = prtcl.euler[1];
pointFlower.dataArray[ieuler + 2] = prtcl.euler[2];
ieuler += 3;
pointFlower.dataArray[imisc] = prtcl.size;
pointFlower.dataArray[imisc + 1] = prtcl.alpha;
imisc += 2;
}
//draw
gl.enable(gl.BLEND);
//gl.disable(gl.DEPTH_TEST);
gl.blendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA);
var prog = pointFlower.program;
useShader(prog);
gl.uniformMatrix4fv(prog.uniforms.uProjection, false, projection.matrix);
gl.uniformMatrix4fv(prog.uniforms.uModelview, false, camera.matrix);
gl.uniform3fv(prog.uniforms.uResolution, renderSpec.array);
gl.uniform3fv(prog.uniforms.uDOF, Vector3.arrayForm(camera.dof));
gl.uniform3fv(prog.uniforms.uFade, Vector3.arrayForm(pointFlower.fader));
gl.bindBuffer(gl.ARRAY_BUFFER, pointFlower.buffer);
gl.bufferData(gl.ARRAY_BUFFER, pointFlower.dataArray, gl.DYNAMIC_DRAW);
gl.vertexAttribPointer(prog.attributes.aPosition, 3, gl.FLOAT, false, 0, pointFlower.positionArrayOffset * Float32Array.BYTES_PER_ELEMENT);
gl.vertexAttribPointer(prog.attributes.aEuler, 3, gl.FLOAT, false, 0, pointFlower.eulerArrayOffset * Float32Array.BYTES_PER_ELEMENT);
gl.vertexAttribPointer(prog.attributes.aMisc, 2, gl.FLOAT, false, 0, pointFlower.miscArrayOffset * Float32Array.BYTES_PER_ELEMENT);
// doubler
for(var i = 1; i < 2; i++) {
var zpos = i * -2.0;
pointFlower.offset[0] = pointFlower.area.x * -1.0;
pointFlower.offset[1] = pointFlower.area.y * -1.0;
pointFlower.offset[2] = pointFlower.area.z * zpos;
gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);
pointFlower.offset[0] = pointFlower.area.x * -1.0;
pointFlower.offset[1] = pointFlower.area.y *  1.0;
pointFlower.offset[2] = pointFlower.area.z * zpos;
gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);
pointFlower.offset[0] = pointFlower.area.x *  1.0;
pointFlower.offset[1] = pointFlower.area.y * -1.0;
pointFlower.offset[2] = pointFlower.area.z * zpos;
gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);
pointFlower.offset[0] = pointFlower.area.x *  1.0;
pointFlower.offset[1] = pointFlower.area.y *  1.0;
pointFlower.offset[2] = pointFlower.area.z * zpos;
gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);
}
//main
pointFlower.offset[0] = 0.0;
pointFlower.offset[1] = 0.0;
pointFlower.offset[2] = 0.0;
gl.uniform3fv(prog.uniforms.uOffset, pointFlower.offset);
gl.drawArrays(gl.POINT, 0, pointFlower.numFlowers);
gl.bindBuffer(gl.ARRAY_BUFFER, null);
unuseShader(prog);
gl.enable(gl.DEPTH_TEST);
gl.disable(gl.BLEND);
}
// effects
//common util
function createEffectProgram(vtxsrc, frgsrc, exunifs, exattrs) {
var ret = {};
var unifs = ['uResolution', 'uSrc', 'uDelta'];
if(exunifs) {
unifs = unifs.concat(exunifs);
}
var attrs = ['aPosition'];
if(exattrs) {
attrs = attrs.concat(exattrs);
}
ret.program = createShader(vtxsrc, frgsrc, unifs, attrs);
useShader(ret.program);
ret.dataArray = new Float32Array([
-1.0, -1.0,
1.0, -1.0,
-1.0,  1.0,
1.0,  1.0
]);
ret.buffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, ret.buffer);
gl.bufferData(gl.ARRAY_BUFFER, ret.dataArray, gl.STATIC_DRAW);
gl.bindBuffer(gl.ARRAY_BUFFER, null);
unuseShader(ret.program);
return ret;
}
// basic usage
// useEffect(prog, srctex({'texture':texid, 'dtxArray':(f32)[dtx, dty]})); //basic initialize
// gl.uniform**(...); //additional uniforms
// drawEffect()
// unuseEffect(prog)
// TEXTURE0 makes src
function useEffect(fxobj, srctex) {
var prog = fxobj.program;
useShader(prog);
gl.uniform3fv(prog.uniforms.uResolution, renderSpec.array);
if(srctex != null) {
gl.uniform2fv(prog.uniforms.uDelta, srctex.dtxArray);
gl.uniform1i(prog.uniforms.uSrc, 0);
gl.activeTexture(gl.TEXTURE0);
gl.bindTexture(gl.TEXTURE_2D, srctex.texture);
}
}
function drawEffect(fxobj) {
gl.bindBuffer(gl.ARRAY_BUFFER, fxobj.buffer);
gl.vertexAttribPointer(fxobj.program.attributes.aPosition, 2, gl.FLOAT, false, 0, 0);
gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
}
function unuseEffect(fxobj) {
unuseShader(fxobj.program);
}
var effectLib = {};
function createEffectLib() {
var vtxsrc, frgsrc;
//common
var cmnvtxsrc = document.getElementById("fx_common_vsh").textContent;
//background
frgsrc = document.getElementById("bg_fsh").textContent;
effectLib.sceneBg = createEffectProgram(cmnvtxsrc, frgsrc, ['uTimes'], null);
// make brightpixels buffer
frgsrc = document.getElementById("fx_brightbuf_fsh").textContent;
effectLib.mkBrightBuf = createEffectProgram(cmnvtxsrc, frgsrc, null, null);
// direction blur
frgsrc = document.getElementById("fx_dirblur_r4_fsh").textContent;
effectLib.dirBlur = createEffectProgram(cmnvtxsrc, frgsrc, ['uBlurDir'], null);
//final composite
vtxsrc = document.getElementById("pp_final_vsh").textContent;
frgsrc = document.getElementById("pp_final_fsh").textContent;
effectLib.finalComp = createEffectProgram(vtxsrc, frgsrc, ['uBloom'], null);
}
// background
function createBackground() {
//console.log("create background");
}
function initBackground() {
//console.log("init background");
}
function renderBackground() {
gl.disable(gl.DEPTH_TEST);
useEffect(effectLib.sceneBg, null);
gl.uniform2f(effectLib.sceneBg.program.uniforms.uTimes, timeInfo.elapsed, timeInfo.delta);
drawEffect(effectLib.sceneBg);
unuseEffect(effectLib.sceneBg);
gl.enable(gl.DEPTH_TEST);
}
// post process
var postProcess = {};
function createPostProcess() {
//console.log("create post process");
}
function initPostProcess() {
//console.log("init post process");
}
function renderPostProcess() {
gl.enable(gl.TEXTURE_2D);
gl.disable(gl.DEPTH_TEST);
var bindRT = function (rt, isclear) {
gl.bindFramebuffer(gl.FRAMEBUFFER, rt.frameBuffer);
gl.viewport(0, 0, rt.width, rt.height);
if(isclear) {
gl.clearColor(0, 0, 0, 0);
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
}
};
//make bright buff
bindRT(renderSpec.wHalfRT0, true);
useEffect(effectLib.mkBrightBuf, renderSpec.mainRT);
drawEffect(effectLib.mkBrightBuf);
unuseEffect(effectLib.mkBrightBuf);
// make bloom
for(var i = 0; i < 2; i++) {
var p = 1.5 + 1 * i;
var s = 2.0 + 1 * i;
bindRT(renderSpec.wHalfRT1, true);
useEffect(effectLib.dirBlur, renderSpec.wHalfRT0);
gl.uniform4f(effectLib.dirBlur.program.uniforms.uBlurDir, p, 0.0, s, 0.0);
drawEffect(effectLib.dirBlur);
unuseEffect(effectLib.dirBlur);
bindRT(renderSpec.wHalfRT0, true);
useEffect(effectLib.dirBlur, renderSpec.wHalfRT1);
gl.uniform4f(effectLib.dirBlur.program.uniforms.uBlurDir, 0.0, p, 0.0, s);
drawEffect(effectLib.dirBlur);
unuseEffect(effectLib.dirBlur);
}
//display
gl.bindFramebuffer(gl.FRAMEBUFFER, null);
gl.viewport(0, 0, renderSpec.width, renderSpec.height);
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
useEffect(effectLib.finalComp, renderSpec.mainRT);
gl.uniform1i(effectLib.finalComp.program.uniforms.uBloom, 1);
gl.activeTexture(gl.TEXTURE1);
gl.bindTexture(gl.TEXTURE_2D, renderSpec.wHalfRT0.texture);
drawEffect(effectLib.finalComp);
unuseEffect(effectLib.finalComp);
gl.enable(gl.DEPTH_TEST);
}
var SceneEnv = {};
function createScene() {
createEffectLib();
createBackground();
createPointFlowers();
createPostProcess();
sceneStandBy = true;
}
function initScene() {
initBackground();
initPointFlowers();
initPostProcess();
//camera.position.z = 17.320508;
camera.position.z = pointFlower.area.z + projection.nearfar[0];
projection.angle = Math.atan2(pointFlower.area.y, camera.position.z + pointFlower.area.z) * 180.0 / Math.PI * 2.0;
Matrix44.loadProjection(projection.matrix, renderSpec.aspect, projection.angle, projection.nearfar[0], projection.nearfar[1]);
}
function renderScene() {
//draw
Matrix44.loadLookAt(camera.matrix, camera.position, camera.lookat, camera.up);
gl.enable(gl.DEPTH_TEST);
//gl.bindFramebuffer(gl.FRAMEBUFFER, null);
gl.bindFramebuffer(gl.FRAMEBUFFER, renderSpec.mainRT.frameBuffer);
gl.viewport(0, 0, renderSpec.mainRT.width, renderSpec.mainRT.height);
gl.clearColor(0.005, 0, 0.05, 0);
gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
renderBackground();
renderPointFlowers();
renderPostProcess();
}
function onResize(e) {
makeCanvasFullScreen(document.getElementById("sakura"));
setViewports();
if(sceneStandBy) {
initScene();
}
}
function setViewports() {
renderSpec.setSize(gl.canvas.width, gl.canvas.height);
gl.clearColor(0.2, 0.2, 0.5, 1.0);
gl.viewport(0, 0, renderSpec.width, renderSpec.height);
var rtfunc = function (rtname, rtw, rth) {
var rt = renderSpec[rtname];
if(rt) deleteRenderTarget(rt);
renderSpec[rtname] = createRenderTarget(rtw, rth);
};
rtfunc('mainRT', renderSpec.width, renderSpec.height);
rtfunc('wFullRT0', renderSpec.width, renderSpec.height);
rtfunc('wFullRT1', renderSpec.width, renderSpec.height);
rtfunc('wHalfRT0', renderSpec.halfWidth, renderSpec.halfHeight);
rtfunc('wHalfRT1', renderSpec.halfWidth, renderSpec.halfHeight);
}
function render() {
renderScene();
}
var animating = true;
function toggleAnimation(elm) {
animating ^= true;
if(animating) animate();
if(elm) {
elm.innerHTML = animating? "Stop":"Start";
}
}
function stepAnimation() {
if(!animating) animate();
}
function animate() {
var curdate = new Date();
timeInfo.elapsed = (curdate - timeInfo.start) / 1000.0;
timeInfo.delta = (curdate - timeInfo.prev) / 1000.0;
timeInfo.prev = curdate;
if(animating) requestAnimationFrame(animate);
render();
}
function makeCanvasFullScreen(canvas) {
var b = document.body;
var d = document.documentElement;
fullw = Math.max(b.clientWidth , b.scrollWidth, d.scrollWidth, d.clientWidth);
fullh = Math.max(b.clientHeight , b.scrollHeight, d.scrollHeight, d.clientHeight);
canvas.width = fullw;
canvas.height = fullh;
}
window.addEventListener('load', function(e) {
var canvas = document.getElementById("sakura");
try {
makeCanvasFullScreen(canvas);
gl = canvas.getContext('experimental-webgl');
} catch(e) {
alert("WebGL not supported." + e);
console.error(e);
return;
}
window.addEventListener('resize', onResize);
setViewports();
createScene();
initScene();
timeInfo.start = new Date();
timeInfo.prev = timeInfo.start;
animate();
});
//set window.requestAnimationFrame
(function (w, r) {
w['r'+r] = w['r'+r] || w['webkitR'+r] || w['mozR'+r] || w['msR'+r] || w['oR'+r] || function(c){ w.setTimeout(c, 1000 / 60); };
})(window, 'equestAnimationFrame');
</script>
</BODY>
</HTML>

由于有不少网友们问我关于如何运行的问题,我在这里提供一个快捷的方法:
只要复制代码放到https://www.runoob.com/runcode粘贴上去运行就可以了的!
效果图如下:
在这里插入图片描述
喜欢的小伙伴记得点赞加收藏哈!!!!在这里插入图片描述
若是上面的没有出效果,试一下下面的

升级版樱花飘落

https://blog.csdn.net/qq_44739706/article/details/109460353

版权声明:本文内容由互联网用户自发贡献,该文观点仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 举报,一经查实,本站将立刻删除。

发布者:全栈程序员-用户IM,转载请注明出处:https://javaforall.cn/161660.html原文链接:https://javaforall.cn

【正版授权,激活自己账号】: Jetbrains全家桶Ide使用,1年售后保障,每天仅需1毛

【官方授权 正版激活】: 官方授权 正版激活 支持Jetbrains家族下所有IDE 使用个人JB账号...

(0)
blank

相关推荐

发表回复

您的电子邮箱地址不会被公开。

关注全栈程序员社区公众号