'use strict';

function _iterableToArrayLimit(arr, i) {
  var _i = null == arr ? null : "undefined" != typeof Symbol && arr[Symbol.iterator] || arr["@@iterator"];
  if (null != _i) {
    var _s,
      _e,
      _x,
      _r,
      _arr = [],
      _n = !0,
      _d = !1;
    try {
      if (_x = (_i = _i.call(arr)).next, 0 === i) {
        if (Object(_i) !== _i) return;
        _n = !1;
      } else for (; !(_n = (_s = _x.call(_i)).done) && (_arr.push(_s.value), _arr.length !== i); _n = !0);
    } catch (err) {
      _d = !0, _e = err;
    } finally {
      try {
        if (!_n && null != _i.return && (_r = _i.return(), Object(_r) !== _r)) return;
      } finally {
        if (_d) throw _e;
      }
    }
    return _arr;
  }
}
function _slicedToArray(arr, i) {
  return _arrayWithHoles(arr) || _iterableToArrayLimit(arr, i) || _unsupportedIterableToArray(arr, i) || _nonIterableRest();
}
function _toConsumableArray(arr) {
  return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _unsupportedIterableToArray(arr) || _nonIterableSpread();
}
function _arrayWithoutHoles(arr) {
  if (Array.isArray(arr)) return _arrayLikeToArray(arr);
}
function _arrayWithHoles(arr) {
  if (Array.isArray(arr)) return arr;
}
function _iterableToArray(iter) {
  if (typeof Symbol !== "undefined" && iter[Symbol.iterator] != null || iter["@@iterator"] != null) return Array.from(iter);
}
function _unsupportedIterableToArray(o, minLen) {
  if (!o) return;
  if (typeof o === "string") return _arrayLikeToArray(o, minLen);
  var n = Object.prototype.toString.call(o).slice(8, -1);
  if (n === "Object" && o.constructor) n = o.constructor.name;
  if (n === "Map" || n === "Set") return Array.from(o);
  if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen);
}
function _arrayLikeToArray(arr, len) {
  if (len == null || len > arr.length) len = arr.length;
  for (var i = 0, arr2 = new Array(len); i < len; i++) arr2[i] = arr[i];
  return arr2;
}
function _nonIterableSpread() {
  throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
}
function _nonIterableRest() {
  throw new TypeError("Invalid attempt to destructure non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
}

var rgba = require('color-normalize');
var getBounds = require('array-bounds');
var colorId = require('color-id');
var cluster = require('@plotly/point-cluster');
var extend = require('object-assign');
var glslify = require('glslify');
var pick = require('pick-by-alias');
var updateDiff = require('update-diff');
var flatten = require('flatten-vertex-data');
var ie = require('is-iexplorer');
var f32 = require('to-float32');
var parseRect = require('parse-rect');
var scatter = Scatter;
function Scatter(regl, options) {
  var _this = this;
  if (!(this instanceof Scatter)) return new Scatter(regl, options);
  if (typeof regl === 'function') {
    if (!options) options = {};
    options.regl = regl;
  } else {
    options = regl;
    regl = null;
  }
  if (options && options.length) options.positions = options;
  regl = options.regl;

  // persistent variables
  var gl = regl._gl,
    paletteTexture,
    palette = [],
    paletteIds = {},
    // state
    groups = [],
    // textures for marker keys
    markerTextures = [null],
    markerCache = [null];
  var maxColors = 255,
    maxSize = 100;

  // direct color buffer mode
  // IE does not support palette anyways
  this.tooManyColors = ie;

  // texture with color palette
  paletteTexture = regl.texture({
    data: new Uint8Array(maxColors * 4),
    width: maxColors,
    height: 1,
    type: 'uint8',
    format: 'rgba',
    wrapS: 'clamp',
    wrapT: 'clamp',
    mag: 'nearest',
    min: 'nearest'
  });
  extend(this, {
    regl: regl,
    gl: gl,
    groups: groups,
    markerCache: markerCache,
    markerTextures: markerTextures,
    palette: palette,
    paletteIds: paletteIds,
    paletteTexture: paletteTexture,
    maxColors: maxColors,
    maxSize: maxSize,
    canvas: gl.canvas
  });
  this.update(options);

  // common shader options
  var shaderOptions = {
    uniforms: {
      constPointSize: !!options.constPointSize,
      opacity: regl.prop('opacity'),
      paletteSize: function paletteSize(ctx, prop) {
        return [_this.tooManyColors ? 0 : maxColors, paletteTexture.height];
      },
      pixelRatio: regl.context('pixelRatio'),
      scale: regl.prop('scale'),
      scaleFract: regl.prop('scaleFract'),
      translate: regl.prop('translate'),
      translateFract: regl.prop('translateFract'),
      markerTexture: regl.prop('markerTexture'),
      paletteTexture: paletteTexture
    },
    attributes: {
      // FIXME: optimize these parts
      x: function x(ctx, prop) {
        return prop.xAttr || {
          buffer: prop.positionBuffer,
          stride: 8,
          offset: 0
        };
      },
      y: function y(ctx, prop) {
        return prop.yAttr || {
          buffer: prop.positionBuffer,
          stride: 8,
          offset: 4
        };
      },
      xFract: function xFract(ctx, prop) {
        return prop.xAttr ? {
          constant: [0, 0]
        } : {
          buffer: prop.positionFractBuffer,
          stride: 8,
          offset: 0
        };
      },
      yFract: function yFract(ctx, prop) {
        return prop.yAttr ? {
          constant: [0, 0]
        } : {
          buffer: prop.positionFractBuffer,
          stride: 8,
          offset: 4
        };
      },
      size: function size(ctx, prop) {
        return prop.size.length ? {
          buffer: prop.sizeBuffer,
          stride: 2,
          offset: 0
        } : {
          constant: [Math.round(prop.size * 255 / _this.maxSize)]
        };
      },
      borderSize: function borderSize(ctx, prop) {
        return prop.borderSize.length ? {
          buffer: prop.sizeBuffer,
          stride: 2,
          offset: 1
        } : {
          constant: [Math.round(prop.borderSize * 255 / _this.maxSize)]
        };
      },
      colorId: function colorId(ctx, prop) {
        return prop.color.length ? {
          buffer: prop.colorBuffer,
          stride: _this.tooManyColors ? 8 : 4,
          offset: 0
        } : {
          constant: _this.tooManyColors ? palette.slice(prop.color * 4, prop.color * 4 + 4) : [prop.color]
        };
      },
      borderColorId: function borderColorId(ctx, prop) {
        return prop.borderColor.length ? {
          buffer: prop.colorBuffer,
          stride: _this.tooManyColors ? 8 : 4,
          offset: _this.tooManyColors ? 4 : 2
        } : {
          constant: _this.tooManyColors ? palette.slice(prop.borderColor * 4, prop.borderColor * 4 + 4) : [prop.borderColor]
        };
      },
      isActive: function isActive(ctx, prop) {
        return prop.activation === true ? {
          constant: [1]
        } : prop.activation ? prop.activation : {
          constant: [0]
        };
      }
    },
    blend: {
      enable: true,
      color: [0, 0, 0, 1],
      // photoshop blending
      func: {
        srcRGB: 'src alpha',
        dstRGB: 'one minus src alpha',
        srcAlpha: 'one minus dst alpha',
        dstAlpha: 'one'
      }
    },
    scissor: {
      enable: true,
      box: regl.prop('viewport')
    },
    viewport: regl.prop('viewport'),
    stencil: {
      enable: false
    },
    depth: {
      enable: false
    },
    elements: regl.prop('elements'),
    count: regl.prop('count'),
    offset: regl.prop('offset'),
    primitive: 'points'
  };

  // draw sdf-marker
  var markerOptions = extend({}, shaderOptions);
  markerOptions.frag = glslify(["precision highp float;\n#define GLSLIFY 1\n\nuniform float opacity;\nuniform sampler2D markerTexture;\n\nvarying vec4 fragColor, fragBorderColor;\nvarying float fragWidth, fragBorderColorLevel, fragColorLevel;\n\nfloat smoothStep(float x, float y) {\n  return 1.0 / (1.0 + exp(50.0*(x - y)));\n}\n\nvoid main() {\n  float dist = texture2D(markerTexture, gl_PointCoord).r, delta = fragWidth;\n\n  // max-distance alpha\n  if (dist < 0.003) discard;\n\n  // null-border case\n  if (fragBorderColorLevel == fragColorLevel || fragBorderColor.a == 0.) {\n    float colorAmt = smoothstep(.5 - delta, .5 + delta, dist);\n    gl_FragColor = vec4(fragColor.rgb, colorAmt * fragColor.a * opacity);\n  }\n  else {\n    float borderColorAmt = smoothstep(fragBorderColorLevel - delta, fragBorderColorLevel + delta, dist);\n    float colorAmt = smoothstep(fragColorLevel - delta, fragColorLevel + delta, dist);\n\n    vec4 color = fragBorderColor;\n    color.a *= borderColorAmt;\n    color = mix(color, fragColor, colorAmt);\n    color.a *= opacity;\n\n    gl_FragColor = color;\n  }\n\n}\n"]);
  markerOptions.vert = glslify(["precision highp float;\n#define GLSLIFY 1\n\nattribute float x, y, xFract, yFract;\nattribute float size, borderSize;\nattribute vec4 colorId, borderColorId;\nattribute float isActive;\n\n// `invariant` effectively turns off optimizations for the position.\n// We need this because -fast-math on M1 Macs is re-ordering\n// floating point operations in a way that causes floating point\n// precision limits to put points in the wrong locations.\ninvariant gl_Position;\n\nuniform bool constPointSize;\nuniform float pixelRatio;\nuniform vec2 scale, scaleFract, translate, translateFract, paletteSize;\nuniform sampler2D paletteTexture;\n\nconst float maxSize = 100.;\nconst float borderLevel = .5;\n\nvarying vec4 fragColor, fragBorderColor;\nvarying float fragPointSize, fragBorderRadius, fragWidth, fragBorderColorLevel, fragColorLevel;\n\nfloat pointSizeScale = (constPointSize) ? 2. : pixelRatio;\n\nbool isDirect = (paletteSize.x < 1.);\n\nvec4 getColor(vec4 id) {\n  return isDirect ? id / 255. : texture2D(paletteTexture,\n    vec2(\n      (id.x + .5) / paletteSize.x,\n      (id.y + .5) / paletteSize.y\n    )\n  );\n}\n\nvoid main() {\n  // ignore inactive points\n  if (isActive == 0.) return;\n\n  vec2 position = vec2(x, y);\n  vec2 positionFract = vec2(xFract, yFract);\n\n  vec4 color = getColor(colorId);\n  vec4 borderColor = getColor(borderColorId);\n\n  float size = size * maxSize / 255.;\n  float borderSize = borderSize * maxSize / 255.;\n\n  gl_PointSize = 2. * size * pointSizeScale;\n  fragPointSize = size * pixelRatio;\n\n  vec2 pos = (position + translate) * scale\n      + (positionFract + translateFract) * scale\n      + (position + translate) * scaleFract\n      + (positionFract + translateFract) * scaleFract;\n\n  gl_Position = vec4(pos * 2. - 1., 0., 1.);\n\n  fragColor = color;\n  fragBorderColor = borderColor;\n  fragWidth = 1. / gl_PointSize;\n\n  fragBorderColorLevel = clamp(borderLevel - borderLevel * borderSize / size, 0., 1.);\n  fragColorLevel = clamp(borderLevel + (1. - borderLevel) * borderSize / size, 0., 1.);\n}\n"]);
  this.drawMarker = regl(markerOptions);

  // draw circle
  var circleOptions = extend({}, shaderOptions);
  circleOptions.frag = glslify(["precision highp float;\n#define GLSLIFY 1\n\nvarying vec4 fragColor, fragBorderColor;\nvarying float fragBorderRadius, fragWidth;\n\nuniform float opacity;\n\nfloat smoothStep(float edge0, float edge1, float x) {\n\tfloat t;\n\tt = clamp((x - edge0) / (edge1 - edge0), 0.0, 1.0);\n\treturn t * t * (3.0 - 2.0 * t);\n}\n\nvoid main() {\n\tfloat radius, alpha = 1.0, delta = fragWidth;\n\n\tradius = length(2.0 * gl_PointCoord.xy - 1.0);\n\n\tif (radius > 1.0 + delta) {\n\t\tdiscard;\n\t}\n\n\talpha -= smoothstep(1.0 - delta, 1.0 + delta, radius);\n\n\tfloat borderRadius = fragBorderRadius;\n\tfloat ratio = smoothstep(borderRadius - delta, borderRadius + delta, radius);\n\tvec4 color = mix(fragColor, fragBorderColor, ratio);\n\tcolor.a *= alpha * opacity;\n\tgl_FragColor = color;\n}\n"]);
  circleOptions.vert = glslify(["precision highp float;\n#define GLSLIFY 1\n\nattribute float x, y, xFract, yFract;\nattribute float size, borderSize;\nattribute vec4 colorId, borderColorId;\nattribute float isActive;\n\n// `invariant` effectively turns off optimizations for the position.\n// We need this because -fast-math on M1 Macs is re-ordering\n// floating point operations in a way that causes floating point\n// precision limits to put points in the wrong locations.\ninvariant gl_Position;\n\nuniform bool constPointSize;\nuniform float pixelRatio;\nuniform vec2 paletteSize, scale, scaleFract, translate, translateFract;\nuniform sampler2D paletteTexture;\n\nconst float maxSize = 100.;\n\nvarying vec4 fragColor, fragBorderColor;\nvarying float fragBorderRadius, fragWidth;\n\nfloat pointSizeScale = (constPointSize) ? 2. : pixelRatio;\n\nbool isDirect = (paletteSize.x < 1.);\n\nvec4 getColor(vec4 id) {\n  return isDirect ? id / 255. : texture2D(paletteTexture,\n    vec2(\n      (id.x + .5) / paletteSize.x,\n      (id.y + .5) / paletteSize.y\n    )\n  );\n}\n\nvoid main() {\n  // ignore inactive points\n  if (isActive == 0.) return;\n\n  vec2 position = vec2(x, y);\n  vec2 positionFract = vec2(xFract, yFract);\n\n  vec4 color = getColor(colorId);\n  vec4 borderColor = getColor(borderColorId);\n\n  float size = size * maxSize / 255.;\n  float borderSize = borderSize * maxSize / 255.;\n\n  gl_PointSize = (size + borderSize) * pointSizeScale;\n\n  vec2 pos = (position + translate) * scale\n      + (positionFract + translateFract) * scale\n      + (position + translate) * scaleFract\n      + (positionFract + translateFract) * scaleFract;\n\n  gl_Position = vec4(pos * 2. - 1., 0., 1.);\n\n  fragBorderRadius = 1. - 2. * borderSize / (size + borderSize);\n  fragColor = color;\n  fragBorderColor = borderColor.a == 0. || borderSize == 0. ? vec4(color.rgb, 0.) : borderColor;\n  fragWidth = 1. / gl_PointSize;\n}\n"]);

  // polyfill IE
  if (ie) {
    circleOptions.frag = circleOptions.frag.replace('smoothstep', 'smoothStep');
    markerOptions.frag = markerOptions.frag.replace('smoothstep', 'smoothStep');
  }
  this.drawCircle = regl(circleOptions);
}

// single pass defaults
Scatter.defaults = {
  color: 'black',
  borderColor: 'transparent',
  borderSize: 0,
  size: 12,
  opacity: 1,
  marker: undefined,
  viewport: null,
  range: null,
  pixelSize: null,
  count: 0,
  offset: 0,
  bounds: null,
  positions: [],
  snap: 1e4
};

// update & redraw
Scatter.prototype.render = function () {
  if (arguments.length) {
    this.update.apply(this, arguments);
  }
  this.draw();
  return this;
};

// draw all groups or only indicated ones
Scatter.prototype.draw = function () {
  var _this2 = this;
  for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
    args[_key] = arguments[_key];
  }
  var groups = this.groups;

  // if directly array passed - treat as passes
  if (args.length === 1 && Array.isArray(args[0]) && (args[0][0] === null || Array.isArray(args[0][0]))) {
    args = args[0];
  }

  // FIXME: remove once https://github.com/regl-project/regl/issues/474 resolved
  this.regl._refresh();
  if (args.length) {
    for (var i = 0; i < args.length; i++) {
      this.drawItem(i, args[i]);
    }
  }
  // draw all passes
  else {
    groups.forEach(function (group, i) {
      _this2.drawItem(i);
    });
  }
  return this;
};

// draw specific scatter group
Scatter.prototype.drawItem = function (id, els) {
  var groups = this.groups;
  var group = groups[id];

  // debug viewport
  // let { viewport } = group
  // gl.enable(gl.SCISSOR_TEST);
  // gl.scissor(viewport.x, viewport.y, viewport.width, viewport.height);
  // gl.clearColor(0, 0, 0, .5);
  // gl.clear(gl.COLOR_BUFFER_BIT);

  if (typeof els === 'number') {
    id = els;
    group = groups[els];
    els = null;
  }
  if (!(group && group.count && group.opacity)) return;

  // draw circles
  if (group.activation[0]) {
    // TODO: optimize this performance by making groups and regl.this props
    this.drawCircle(this.getMarkerDrawOptions(0, group, els));
  }

  // draw all other available markers
  var batch = [];
  for (var i = 1; i < group.activation.length; i++) {
    if (!group.activation[i] || group.activation[i] !== true && !group.activation[i].data.length) continue;
    batch.push.apply(batch, _toConsumableArray(this.getMarkerDrawOptions(i, group, els)));
  }
  if (batch.length) {
    this.drawMarker(batch);
  }
};

// get options for the marker ids
Scatter.prototype.getMarkerDrawOptions = function (markerId, group, elements) {
  var range = group.range,
    tree = group.tree,
    viewport = group.viewport,
    activation = group.activation,
    selectionBuffer = group.selectionBuffer,
    count = group.count;
  var regl = this.regl;

  // direct points
  if (!tree) {
    // if elements array - draw unclustered points
    if (elements) {
      return [extend({}, group, {
        markerTexture: this.markerTextures[markerId],
        activation: activation[markerId],
        count: elements.length,
        elements: elements,
        offset: 0
      })];
    }
    return [extend({}, group, {
      markerTexture: this.markerTextures[markerId],
      activation: activation[markerId],
      offset: 0
    })];
  }

  // clustered points
  var batch = [];
  var lod = tree.range(range, {
    lod: true,
    px: [(range[2] - range[0]) / viewport.width, (range[3] - range[1]) / viewport.height]
  });

  // enable elements by using selection buffer
  if (elements) {
    var markerActivation = activation[markerId];
    var mask = markerActivation.data;
    var data = new Uint8Array(count);
    for (var i = 0; i < elements.length; i++) {
      var id = elements[i];
      data[id] = mask ? mask[id] : 1;
    }
    selectionBuffer.subdata(data);
  }
  for (var l = lod.length; l--;) {
    var _lod$l = _slicedToArray(lod[l], 2),
      from = _lod$l[0],
      to = _lod$l[1];
    batch.push(extend({}, group, {
      markerTexture: this.markerTextures[markerId],
      activation: elements ? selectionBuffer : activation[markerId],
      offset: from,
      count: to - from
    }));
  }
  return batch;
};

// update groups options
Scatter.prototype.update = function () {
  var _this3 = this;
  for (var _len2 = arguments.length, args = new Array(_len2), _key2 = 0; _key2 < _len2; _key2++) {
    args[_key2] = arguments[_key2];
  }
  if (!args.length) return;

  // passes are as single array
  if (args.length === 1 && Array.isArray(args[0])) args = args[0];
  var groups = this.groups,
    gl = this.gl,
    regl = this.regl,
    maxSize = this.maxSize,
    maxColors = this.maxColors,
    palette = this.palette;
  this.groups = groups = args.map(function (options, i) {
    var group = groups[i];
    if (options === undefined) return group;
    if (options === null) options = {
      positions: null
    };else if (typeof options === 'function') options = {
      ondraw: options
    };else if (typeof options[0] === 'number') options = {
      positions: options
    };

    // copy options to avoid mutation & handle aliases
    options = pick(options, {
      positions: 'positions data points',
      snap: 'snap cluster lod tree',
      size: 'sizes size radius',
      borderSize: 'borderSizes borderSize border-size bordersize borderWidth borderWidths border-width borderwidth stroke-width strokeWidth strokewidth outline',
      color: 'colors color fill fill-color fillColor',
      borderColor: 'borderColors borderColor stroke stroke-color strokeColor',
      marker: 'markers marker shape',
      range: 'range dataBox databox',
      viewport: 'viewport viewPort viewBox viewbox',
      opacity: 'opacity alpha transparency',
      bounds: 'bound bounds boundaries limits',
      tooManyColors: 'tooManyColors palette paletteMode optimizePalette enablePalette'
    });
    if (options.positions === null) options.positions = [];
    if (options.tooManyColors != null) _this3.tooManyColors = options.tooManyColors;
    if (!group) {
      groups[i] = group = {
        id: i,
        scale: null,
        translate: null,
        scaleFract: null,
        translateFract: null,
        // buffers for active markers
        activation: [],
        // buffer for filtered markers
        selectionBuffer: regl.buffer({
          data: new Uint8Array(0),
          usage: 'stream',
          type: 'uint8'
        }),
        // buffers with data: it is faster to switch them per-pass
        // than provide one congregate buffer
        sizeBuffer: regl.buffer({
          data: new Uint8Array(0),
          usage: 'dynamic',
          type: 'uint8'
        }),
        colorBuffer: regl.buffer({
          data: new Uint8Array(0),
          usage: 'dynamic',
          type: 'uint8'
        }),
        positionBuffer: regl.buffer({
          data: new Uint8Array(0),
          usage: 'dynamic',
          type: 'float'
        }),
        positionFractBuffer: regl.buffer({
          data: new Uint8Array(0),
          usage: 'dynamic',
          type: 'float'
        })
      };
      options = extend({}, Scatter.defaults, options);
    }

    // force update triggers
    if (options.positions && !('marker' in options)) {
      options.marker = group.marker;
      delete group.marker;
    }

    // updating markers cause recalculating snapping
    if (options.marker && !('positions' in options)) {
      options.positions = group.positions;
      delete group.positions;
    }

    // global count of points
    var hasSize = 0,
      hasColor = 0;
    updateDiff(group, options, [{
      snap: true,
      size: function size(s, group) {
        if (s == null) s = Scatter.defaults.size;
        hasSize += s && s.length ? 1 : 0;
        return s;
      },
      borderSize: function borderSize(s, group) {
        if (s == null) s = Scatter.defaults.borderSize;
        hasSize += s && s.length ? 1 : 0;
        return s;
      },
      opacity: parseFloat,
      // add colors to palette, save references
      color: function color(c, group) {
        if (c == null) c = Scatter.defaults.color;
        c = _this3.updateColor(c);
        hasColor++;
        return c;
      },
      borderColor: function borderColor(c, group) {
        if (c == null) c = Scatter.defaults.borderColor;
        c = _this3.updateColor(c);
        hasColor++;
        return c;
      },
      bounds: function bounds(_bounds, group, options) {
        if (!('range' in options)) options.range = null;
        return _bounds;
      },
      positions: function positions(_positions, group, options) {
        var snap = group.snap;
        var positionBuffer = group.positionBuffer,
          positionFractBuffer = group.positionFractBuffer,
          selectionBuffer = group.selectionBuffer;

        // separate buffers for x/y coordinates
        if (_positions.x || _positions.y) {
          if (_positions.x.length) {
            group.xAttr = {
              buffer: regl.buffer(_positions.x),
              offset: 0,
              stride: 4,
              count: _positions.x.length
            };
          } else {
            group.xAttr = {
              buffer: _positions.x.buffer,
              offset: _positions.x.offset * 4 || 0,
              stride: (_positions.x.stride || 1) * 4,
              count: _positions.x.count
            };
          }
          if (_positions.y.length) {
            group.yAttr = {
              buffer: regl.buffer(_positions.y),
              offset: 0,
              stride: 4,
              count: _positions.y.length
            };
          } else {
            group.yAttr = {
              buffer: _positions.y.buffer,
              offset: _positions.y.offset * 4 || 0,
              stride: (_positions.y.stride || 1) * 4,
              count: _positions.y.count
            };
          }
          group.count = Math.max(group.xAttr.count, group.yAttr.count);
          return _positions;
        }
        _positions = flatten(_positions, 'float64');
        var count = group.count = Math.floor(_positions.length / 2);
        var bounds = group.bounds = count ? getBounds(_positions, 2) : null;

        // if range is not provided updated - recalc it
        if (!options.range && !group.range) {
          delete group.range;
          options.range = bounds;
        }

        // reset marker
        if (!options.marker && !group.marker) {
          delete group.marker;
          options.marker = null;
        }

        // build cluster tree if required
        if (snap && (snap === true || count > snap)) {
          group.tree = cluster(_positions, {
            bounds: bounds
          });
        }
        // existing tree instance
        else if (snap && snap.length) {
          group.tree = snap;
        }
        if (group.tree) {
          var opts = {
            primitive: 'points',
            usage: 'static',
            data: group.tree,
            type: 'uint32'
          };
          if (group.elements) group.elements(opts);else group.elements = regl.elements(opts);
        }

        // update position buffers
        var float_data = f32.float32(_positions);
        positionBuffer({
          data: float_data,
          usage: 'dynamic'
        });
        var frac_data = f32.fract32(_positions, float_data);
        positionFractBuffer({
          data: frac_data,
          usage: 'dynamic'
        });

        // expand selectionBuffer
        selectionBuffer({
          data: new Uint8Array(count),
          type: 'uint8',
          usage: 'stream'
        });
        return _positions;
      }
    }, {
      // create marker ids corresponding to known marker textures
      marker: function marker(markers, group, options) {
        var activation = group.activation;

        // reset marker elements
        activation.forEach(function (buffer) {
          return buffer && buffer.destroy && buffer.destroy();
        });
        activation.length = 0;

        // single sdf marker
        if (!markers || typeof markers[0] === 'number') {
          var id = _this3.addMarker(markers);
          activation[id] = true;
        }

        // per-point markers use mask buffers to enable markers in vert shader
        else {
          var markerMasks = [];
          for (var _i = 0, l = Math.min(markers.length, group.count); _i < l; _i++) {
            var _id = _this3.addMarker(markers[_i]);
            if (!markerMasks[_id]) markerMasks[_id] = new Uint8Array(group.count);

            // enable marker by default
            markerMasks[_id][_i] = 1;
          }
          for (var _id2 = 0; _id2 < markerMasks.length; _id2++) {
            if (!markerMasks[_id2]) continue;
            var opts = {
              data: markerMasks[_id2],
              type: 'uint8',
              usage: 'static'
            };
            if (!activation[_id2]) {
              activation[_id2] = regl.buffer(opts);
            } else {
              activation[_id2](opts);
            }
            activation[_id2].data = markerMasks[_id2];
          }
        }
        return markers;
      },
      range: function range(_range, group, options) {
        var bounds = group.bounds;

        // FIXME: why do we need this?
        if (!bounds) return;
        if (!_range) _range = bounds;
        group.scale = [1 / (_range[2] - _range[0]), 1 / (_range[3] - _range[1])];
        group.translate = [-_range[0], -_range[1]];
        group.scaleFract = f32.fract(group.scale);
        group.translateFract = f32.fract(group.translate);
        return _range;
      },
      viewport: function viewport(vp) {
        var rect = parseRect(vp || [gl.drawingBufferWidth, gl.drawingBufferHeight]);

        // normalize viewport to the canvas coordinates
        // rect.y = gl.drawingBufferHeight - rect.height - rect.y

        return rect;
      }
    }]);

    // update size buffer, if needed
    if (hasSize) {
      var _group = group,
        count = _group.count,
        size = _group.size,
        borderSize = _group.borderSize,
        sizeBuffer = _group.sizeBuffer;
      var sizes = new Uint8Array(count * 2);
      if (size.length || borderSize.length) {
        for (var _i2 = 0; _i2 < count; _i2++) {
          // we downscale size to allow for fractions
          sizes[_i2 * 2] = Math.round((size[_i2] == null ? size : size[_i2]) * 255 / maxSize);
          sizes[_i2 * 2 + 1] = Math.round((borderSize[_i2] == null ? borderSize : borderSize[_i2]) * 255 / maxSize);
        }
      }
      sizeBuffer({
        data: sizes,
        usage: 'dynamic'
      });
    }

    // update color buffer if needed
    if (hasColor) {
      var _group2 = group,
        _count = _group2.count,
        color = _group2.color,
        borderColor = _group2.borderColor,
        colorBuffer = _group2.colorBuffer;
      var colors;

      // if too many colors - put colors to buffer directly
      if (_this3.tooManyColors) {
        if (color.length || borderColor.length) {
          colors = new Uint8Array(_count * 8);
          for (var _i3 = 0; _i3 < _count; _i3++) {
            var _colorId = color[_i3];
            colors[_i3 * 8] = palette[_colorId * 4];
            colors[_i3 * 8 + 1] = palette[_colorId * 4 + 1];
            colors[_i3 * 8 + 2] = palette[_colorId * 4 + 2];
            colors[_i3 * 8 + 3] = palette[_colorId * 4 + 3];
            var borderColorId = borderColor[_i3];
            colors[_i3 * 8 + 4] = palette[borderColorId * 4];
            colors[_i3 * 8 + 5] = palette[borderColorId * 4 + 1];
            colors[_i3 * 8 + 6] = palette[borderColorId * 4 + 2];
            colors[_i3 * 8 + 7] = palette[borderColorId * 4 + 3];
          }
        }
      }

      // if limited amount of colors - keep palette color picking
      // that saves significant memory
      else {
        if (color.length || borderColor.length) {
          // we need slight data increase by 2 due to vec4 borderId in shader
          colors = new Uint8Array(_count * 4 + 2);
          for (var _i4 = 0; _i4 < _count; _i4++) {
            // put color coords in palette texture
            if (color[_i4] != null) {
              colors[_i4 * 4] = color[_i4] % maxColors;
              colors[_i4 * 4 + 1] = Math.floor(color[_i4] / maxColors);
            }
            if (borderColor[_i4] != null) {
              colors[_i4 * 4 + 2] = borderColor[_i4] % maxColors;
              colors[_i4 * 4 + 3] = Math.floor(borderColor[_i4] / maxColors);
            }
          }
        }
      }
      colorBuffer({
        data: colors || new Uint8Array(0),
        type: 'uint8',
        usage: 'dynamic'
      });
    }
    return group;
  });
};

// get (and create) marker texture id
Scatter.prototype.addMarker = function (sdf) {
  var markerTextures = this.markerTextures,
    regl = this.regl,
    markerCache = this.markerCache;
  var pos = sdf == null ? 0 : markerCache.indexOf(sdf);
  if (pos >= 0) return pos;

  // convert sdf to 0..255 range
  var distArr;
  if (sdf instanceof Uint8Array || sdf instanceof Uint8ClampedArray) {
    distArr = sdf;
  } else {
    distArr = new Uint8Array(sdf.length);
    for (var i = 0, l = sdf.length; i < l; i++) {
      distArr[i] = sdf[i] * 255;
    }
  }
  var radius = Math.floor(Math.sqrt(distArr.length));
  pos = markerTextures.length;
  markerCache.push(sdf);
  markerTextures.push(regl.texture({
    channels: 1,
    data: distArr,
    radius: radius,
    mag: 'linear',
    min: 'linear'
  }));
  return pos;
};

// register color to palette, return it's index or list of indexes
Scatter.prototype.updateColor = function (colors) {
  var paletteIds = this.paletteIds,
    palette = this.palette,
    maxColors = this.maxColors;
  if (!Array.isArray(colors)) {
    colors = [colors];
  }
  var idx = [];

  // if color groups - flatten them
  if (typeof colors[0] === 'number') {
    var grouped = [];
    if (Array.isArray(colors)) {
      for (var i = 0; i < colors.length; i += 4) {
        grouped.push(colors.slice(i, i + 4));
      }
    } else {
      for (var _i5 = 0; _i5 < colors.length; _i5 += 4) {
        grouped.push(colors.subarray(_i5, _i5 + 4));
      }
    }
    colors = grouped;
  }
  for (var _i6 = 0; _i6 < colors.length; _i6++) {
    var color = colors[_i6];
    color = rgba(color, 'uint8');
    var id = colorId(color, false);

    // if new color - save it
    if (paletteIds[id] == null) {
      var pos = palette.length;
      paletteIds[id] = Math.floor(pos / 4);
      palette[pos] = color[0];
      palette[pos + 1] = color[1];
      palette[pos + 2] = color[2];
      palette[pos + 3] = color[3];
    }
    idx[_i6] = paletteIds[id];
  }

  // detect if too many colors in palette
  if (!this.tooManyColors && palette.length > maxColors * 4) this.tooManyColors = true;

  // limit max color
  this.updatePalette(palette);

  // keep static index for single-color property
  return idx.length === 1 ? idx[0] : idx;
};
Scatter.prototype.updatePalette = function (palette) {
  if (this.tooManyColors) return;
  var maxColors = this.maxColors,
    paletteTexture = this.paletteTexture;
  var requiredHeight = Math.ceil(palette.length * .25 / maxColors);

  // pad data
  if (requiredHeight > 1) {
    palette = palette.slice();
    for (var i = palette.length * .25 % maxColors; i < requiredHeight * maxColors; i++) {
      palette.push(0, 0, 0, 0);
    }
  }

  // ensure height
  if (paletteTexture.height < requiredHeight) {
    paletteTexture.resize(maxColors, requiredHeight);
  }

  // update full data
  paletteTexture.subimage({
    width: Math.min(palette.length * .25, maxColors),
    height: requiredHeight,
    data: palette
  }, 0, 0);
};

// remove unused stuff
Scatter.prototype.destroy = function () {
  this.groups.forEach(function (group) {
    group.sizeBuffer.destroy();
    group.positionBuffer.destroy();
    group.positionFractBuffer.destroy();
    group.colorBuffer.destroy();
    group.activation.forEach(function (b) {
      return b && b.destroy && b.destroy();
    });
    group.selectionBuffer.destroy();
    if (group.elements) group.elements.destroy();
  });
  this.groups.length = 0;
  this.paletteTexture.destroy();
  this.markerTextures.forEach(function (txt) {
    return txt && txt.destroy && txt.destroy();
  });
  return this;
};

var extend$1 = require('object-assign');
var reglScatter2d = function reglScatter2d(regl, options) {
  var scatter$1 = new scatter(regl, options);
  var render = scatter$1.render.bind(scatter$1);

  // expose API
  extend$1(render, {
    render: render,
    update: scatter$1.update.bind(scatter$1),
    draw: scatter$1.draw.bind(scatter$1),
    destroy: scatter$1.destroy.bind(scatter$1),
    regl: scatter$1.regl,
    gl: scatter$1.gl,
    canvas: scatter$1.gl.canvas,
    groups: scatter$1.groups,
    markers: scatter$1.markerCache,
    palette: scatter$1.palette
  });
  return render;
};

module.exports = reglScatter2d;