3D樱花飘落特效

樱花特效

这是一款基于HTML5实现唯美的3D花瓣飘落效果源码。在明亮的背景下呈现出大量花瓣不规则飘落的视觉效果，且花瓣飘落中呈现出3D立体翻转的效果。是一款非常经典的HTML5动画特效代码。建议使用支持HTML5与css3效果较好的火狐(Firefox)或谷歌(Chrome)等浏览器预览本源码。

源码部分

以下为 html 和 html 以及javascript部分代码 完整代码可 查看 樱花特效

<canvas id="sakura">canvas>

<style>
    body {
        padding: 0;
        margin: 0;
        overflow: hidden;
        height: 600px;
    }

    canvas {
        padding: 0;
        margin: 0;
    }
style>

<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>