樱花效果

FOR YOU GIRL 以梦为马,不负韶华 LOVE YOU FOREVER

HTML樱花飘落

实现代码

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    <title>落花纷飞</title>
    <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>
    <div
      style="
        position: absolute;
        top: 30%;
        left: 18%;
        z-index: 1;
        width: 430px;
        height: 400px;
        font-size: 30px;
        color: #ff826c;
        font-family: 等线;
      "
    >
      <div style="margin-left: 10px; margin-bottom: 20px">FOR YOU:Girl&nbsp;</div>
      <div style="margin-left: 68px; margin-bottom: 20px">
        以梦为马 不负韶华
      </div>
      <div style="margin-left: 180px; font-size: 24px">LOVE YOU FROEVER</div>
    </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>
    <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>
    <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>
    <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>
      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, 
        delta: 0,
        elapsed: 0, 
      };
      var gl;
      var renderSpec = {
        width: 0,
        height: 0,
        aspect: 1,
        array: new Float32Array(3),
        halfWidth: 0,
        halfHeight: 0,
        halfArray: new Float32Array(3),
      };
      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() {
        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);
        pointFlower.numFlowers = 1600;
        pointFlower.particles = new Array(pointFlower.numFlowers);
        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() {
        pointFlower.area = Vector3.create(20.0, 20.0, 20.0);
        pointFlower.area.x = pointFlower.area.y * renderSpec.aspect;
        pointFlower.fader.x = 10.0; 
        pointFlower.fader.y = pointFlower.area.z; 
        pointFlower.fader.z = 0.1; 
        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];
          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);
          tmpprtcl.setRotation(
            symmetryrand() * PI2 * 0.5,
            symmetryrand() * PI2 * 0.5,
            symmetryrand() * PI2 * 0.5
          );
          tmpprtcl.setPosition(
            symmetryrand() * pointFlower.area.x,
            symmetryrand() * pointFlower.area.y,
            symmetryrand() * pointFlower.area.z
          );
          tmpprtcl.setEulerAngles(
            Math.random() * Math.PI * 2.0,
            Math.random() * Math.PI * 2.0,
            Math.random() * Math.PI * 2.0
          );
          tmpprtcl.setSize(0.9 + Math.random() * 0.1);
        }
      }
      function renderPointFlowers() {
        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) {
            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;
          prtcl.zkey =
            camera.matrix[2] * prtcl.position[0] +
            camera.matrix[6] * prtcl.position[1] +
            camera.matrix[10] * prtcl.position[2] +
            camera.matrix[14];
        }
        pointFlower.particles.sort(function (p0, p1) {
          return p0.zkey - p1.zkey;
        });
        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;
        }
        gl.enable(gl.BLEND);
        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
        );
        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);
        }
        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);
      }
      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;
      }
      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;
        var cmnvtxsrc = document.getElementById("fx_common_vsh").textContent;
        frgsrc = document.getElementById("bg_fsh").textContent;
        effectLib.sceneBg = createEffectProgram(
          cmnvtxsrc,
          frgsrc,
          ["uTimes"],
          null
        );
        frgsrc = document.getElementById("fx_brightbuf_fsh").textContent;
        effectLib.mkBrightBuf = createEffectProgram(
          cmnvtxsrc,
          frgsrc,
          null,
          null
        );
        frgsrc = document.getElementById("fx_dirblur_r4_fsh").textContent;
        effectLib.dirBlur = createEffectProgram(
          cmnvtxsrc,
          frgsrc,
          ["uBlurDir"],
          null
        );
        vtxsrc = document.getElementById("pp_final_vsh").textContent;
        frgsrc = document.getElementById("pp_final_fsh").textContent;
        effectLib.finalComp = createEffectProgram(
          vtxsrc,
          frgsrc,
          ["uBloom"],
          null
        );
      }
      function createBackground() {
      }
      function initBackground() {
      }
      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);
      }
      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);
          }
        };
        bindRT(renderSpec.wHalfRT0, true);
        useEffect(effectLib.mkBrightBuf, renderSpec.mainRT);
        drawEffect(effectLib.mkBrightBuf);
        unuseEffect(effectLib.mkBrightBuf);
        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);
        }
        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 = 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() {
        Matrix44.loadLookAt(
          camera.matrix,
          camera.position,
          camera.lookat,
          camera.up
        );
        gl.enable(gl.DEPTH_TEST);
        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();
      });
      (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>

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