bk.Line3D = function (points,colors){this.points = points;this.colors = colors;
}bk.Line3D.prototype.computeData = function() {var len = this.points.length;var count = len * 3 * 2;    var position = new Float32Array(count);var positionPrev =  new Float32Array(count);var positionNext = new Float32Array(count);var color = new Float32Array(count);var offset = new Float32Array(len * 2);var indicesCount = 3 * 2 * (len - 1);var indices = new Uint16Array(indicesCount);var triangleOffset = 0,vertexOffset = 0;for(var i = 0; i < len; i ++){var i3 = i * 3 * 2;var point = this.points[i];position[i3 + 0] = point.x;position[i3 + 1] = point.y;position[i3 + 2] = point.z;position[i3 + 3] = point.x;position[i3 + 4] = point.y;position[i3 + 5] = point.z;var r = (i + 1) / len;var g = Math.random();var b = Math.random();g = r;b = 0;r =  1- r;color[i3 + 0] = r;color[i3 + 1] = g;color[i3 + 2] = b;color[i3 + 3] = r;color[i3 + 4] = g;color[i3 + 5] = b;if (i < count - 1) {var i3p = i3 + 6;positionNext[i3p + 0] = point.x;positionNext[i3p + 1] = point.y;positionNext[i3p + 2] = point.z;positionNext[i3p + 3] = point.x;positionNext[i3p + 4] = point.y;positionNext[i3p + 5] = point.z;}if (i > 0) {var i3n = i3 - 6;positionPrev[i3n + 0] = point.x;positionPrev[i3n + 1] = point.y;positionPrev[i3n + 2] = point.z;positionPrev[i3n + 3] = point.x;positionPrev[i3n + 4] = point.y;positionPrev[i3n + 5] = point.z;}var idx = 3 * i;var i2 = i * 2;offset[i2 + 0]  = 5;offset[i2 + 1]  = -5;}var end = count - 1;for(i = 0;i < 6 ;i ++){positionNext[i] = positionNext[i + 6];positionPrev[end - i] = positionPrev[end - i - 6];}for(i = 0;i < indicesCount ;i ++){if(i % 2 == 0){indices[triangleOffset ++] = i;indices[triangleOffset ++] = i + 1;indices[triangleOffset ++] = i + 2;}else{indices[triangleOffset ++] = i + 1;indices[triangleOffset ++] = i;indices[triangleOffset ++] = i + 2;}}this.position  = position;this.positionNext  = positionNext;this.positionPrev = positionPrev;this.color = color;this.offset = offset;this.indices = indices;
};

var lineVS = `attribute vec3 aPosition;attribute vec3 aPositionPre;attribute vec3 aPositionNext;attribute float aOffset;attribute vec3 aColor;varying  vec3  vColor;uniform mat4 uWorldViewProjection;uniform vec4 uViewport;uniform float uNear;uniform mat4 uViewMatrix;uniform mat4 uProjectMatrix;vec4 clipNear(vec4 p1,vec4 p2){float n = (p1.w - uNear) / (p1.w - p2.w);return vec4(mix(p1.xy,p2.xy,n),-uNear,uNear);}void main(){vec4 prevProj = uWorldViewProjection * vec4(aPositionPre, 1.0);vec4 currProj = uWorldViewProjection * vec4(aPosition, 1.0);vec4 nextProj = uWorldViewProjection * vec4(aPositionNext, 1.0);if (currProj.w < 0.0) {if (prevProj.w < 0.0) {currProj = clipNear(currProj, nextProj);}else {currProj = clipNear(currProj, prevProj);}}vec2 prevScreen = (prevProj.xy / abs(prevProj.w) + 1.0) * 0.5 * uViewport.zw;vec2 currScreen = (currProj.xy / abs(currProj.w) + 1.0) * 0.5 * uViewport.zw;vec2 nextScreen = (nextProj.xy / abs(nextProj.w) + 1.0) * 0.5 * uViewport.zw;vec2 dir;float len = aOffset;if(aPosition == aPositionPre){dir = normalize(nextScreen - currScreen);}else if(aPosition == aPositionNext){dir = normalize(currScreen - prevScreen);}else {vec2 dirA = normalize(currScreen - prevScreen);vec2 dirB = normalize(nextScreen - currScreen);vec2 tanget = normalize(dirA + dirB);float miter = 1.0 / max(dot(tanget,dirA),0.5);len *= miter;dir = tanget;}dir = vec2(-dir.y,dir.x) * len;currScreen += dir;currProj.xy = (currScreen / uViewport.zw - 0.5) * 2.0 * abs(currProj.w);vec4 pos = uProjectMatrix * uViewMatrix *  vec4(aPosition,1.0);vColor = aColor;gl_Position = currProj;}
`;