michael@0: /* -*- Mode: javascript; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: "use strict";
michael@0: 
michael@0: /**
michael@0:  * Given the initialization data (sizes and information about
michael@0:  * each DOM node) this worker sends back the arrays representing
michael@0:  * vertices, texture coords, colors, indices and all the needed data for
michael@0:  * rendering the DOM visualization mesh.
michael@0:  *
michael@0:  * Used in the TiltVisualization.Presenter object.
michael@0:  */
michael@0: self.onmessage = function TWC_onMessage(event)
michael@0: {
michael@0:   let data = event.data;
michael@0:   let maxGroupNodes = parseInt(data.maxGroupNodes);
michael@0:   let style = data.style;
michael@0:   let texWidth = data.texWidth;
michael@0:   let texHeight = data.texHeight;
michael@0:   let nodesInfo = data.nodesInfo;
michael@0: 
michael@0:   let mesh = {
michael@0:     allVertices: [],
michael@0:     groups: [],
michael@0:     width: 0,
michael@0:     height: 0
michael@0:   };
michael@0: 
michael@0:   let vertices;
michael@0:   let texCoord;
michael@0:   let color;
michael@0:   let stacksIndices;
michael@0:   let wireframeIndices;
michael@0:   let index;
michael@0: 
michael@0:   // seed the random function to get the same values each time
michael@0:   // we're doing this to avoid ugly z-fighting with overlapping nodes
michael@0:   self.random.seed(0);
michael@0: 
michael@0:   // go through all the dom nodes and compute the verts, texcoord etc.
michael@0:   for (let n = 0, len = nodesInfo.length; n < len; n++) {
michael@0: 
michael@0:     // check if we need to start creating a new group
michael@0:     if (n % maxGroupNodes === 0) {
michael@0:       vertices = []; // recreate the arrays used to construct the 3D mesh data
michael@0:       texCoord = [];
michael@0:       color = [];
michael@0:       stacksIndices = [];
michael@0:       wireframeIndices = [];
michael@0:       index = 0;
michael@0:     }
michael@0: 
michael@0:     let info = nodesInfo[n];
michael@0:     let coord = info.coord;
michael@0: 
michael@0:     // calculate the stack x, y, z, width and height coordinates
michael@0:     let z = coord.depth + coord.thickness;
michael@0:     let y = coord.top;
michael@0:     let x = coord.left;
michael@0:     let w = coord.width;
michael@0:     let h = coord.height;
michael@0: 
michael@0:     // the maximum texture size slices the visualization mesh where needed
michael@0:     if (x + w > texWidth) {
michael@0:       w = texWidth - x;
michael@0:     }
michael@0:     if (y + h > texHeight) {
michael@0:       h = texHeight - y;
michael@0:     }
michael@0: 
michael@0:     x += self.random.next();
michael@0:     y += self.random.next();
michael@0:     w -= self.random.next() * 0.1;
michael@0:     h -= self.random.next() * 0.1;
michael@0: 
michael@0:     let xpw = x + w;
michael@0:     let yph = y + h;
michael@0:     let zmt = coord.depth;
michael@0: 
michael@0:     let xotw = x / texWidth;
michael@0:     let yoth = y / texHeight;
michael@0:     let xpwotw = xpw / texWidth;
michael@0:     let yphoth = yph / texHeight;
michael@0: 
michael@0:     // calculate the margin fill color
michael@0:     let fill = style[info.name] || style.highlight.defaultFill;
michael@0: 
michael@0:     let r = fill[0];
michael@0:     let g = fill[1];
michael@0:     let b = fill[2];
michael@0:     let g10 = r * 1.1;
michael@0:     let g11 = g * 1.1;
michael@0:     let g12 = b * 1.1;
michael@0:     let g20 = r * 0.6;
michael@0:     let g21 = g * 0.6;
michael@0:     let g22 = b * 0.6;
michael@0: 
michael@0:     // compute the vertices
michael@0:     vertices.push(x,   y,   z,                                /* front */ // 0
michael@0:                   x,   yph, z,                                            // 1
michael@0:                   xpw, yph, z,                                            // 2
michael@0:                   xpw, y,   z,                                            // 3
michael@0:     // we don't duplicate vertices for the left and right faces, because
michael@0:     // they can be reused from the bottom and top faces; we do, however,
michael@0:     // duplicate some vertices from front face, because it has custom
michael@0:     // texture coordinates which are not shared by the other faces
michael@0:                   x,   y,   z,                                /* front */ // 4
michael@0:                   x,   yph, z,                                            // 5
michael@0:                   xpw, yph, z,                                            // 6
michael@0:                   xpw, y,   z,                                            // 7
michael@0:                   x,   y,   zmt,                              /* back */  // 8
michael@0:                   x,   yph, zmt,                                          // 9
michael@0:                   xpw, yph, zmt,                                          // 10
michael@0:                   xpw, y,   zmt);                                         // 11
michael@0: 
michael@0:     // compute the texture coordinates
michael@0:     texCoord.push(xotw,   yoth,
michael@0:                   xotw,   yphoth,
michael@0:                   xpwotw, yphoth,
michael@0:                   xpwotw, yoth,
michael@0:                   -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0);
michael@0: 
michael@0:     // compute the colors for each vertex in the mesh
michael@0:     color.push(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
michael@0:                g10, g11, g12,
michael@0:                g10, g11, g12,
michael@0:                g10, g11, g12,
michael@0:                g10, g11, g12,
michael@0:                g20, g21, g22,
michael@0:                g20, g21, g22,
michael@0:                g20, g21, g22,
michael@0:                g20, g21, g22);
michael@0: 
michael@0:     let i = index; // number of vertex points, used to create the indices array
michael@0:     let ip1 = i + 1;
michael@0:     let ip2 = ip1 + 1;
michael@0:     let ip3 = ip2 + 1;
michael@0:     let ip4 = ip3 + 1;
michael@0:     let ip5 = ip4 + 1;
michael@0:     let ip6 = ip5 + 1;
michael@0:     let ip7 = ip6 + 1;
michael@0:     let ip8 = ip7 + 1;
michael@0:     let ip9 = ip8 + 1;
michael@0:     let ip10 = ip9 + 1;
michael@0:     let ip11 = ip10 + 1;
michael@0: 
michael@0:     // compute the stack indices
michael@0:     stacksIndices.unshift(i,    ip1,  ip2,  i,    ip2,  ip3,
michael@0:                           ip8,  ip9,  ip5,  ip8,  ip5,  ip4,
michael@0:                           ip7,  ip6,  ip10, ip7,  ip10, ip11,
michael@0:                           ip8,  ip4,  ip7,  ip8,  ip7,  ip11,
michael@0:                           ip5,  ip9,  ip10, ip5,  ip10, ip6);
michael@0: 
michael@0:     // compute the wireframe indices
michael@0:     if (coord.thickness !== 0) {
michael@0:       wireframeIndices.unshift(i,    ip1, ip1,  ip2,
michael@0:                                ip2,  ip3, ip3,  i,
michael@0:                                ip8,  i,   ip9,  ip1,
michael@0:                                ip11, ip3, ip10, ip2);
michael@0:     }
michael@0: 
michael@0:     // there are 12 vertices in a stack representing a node
michael@0:     index += 12;
michael@0: 
michael@0:     // set the maximum mesh width and height to calculate the center offset
michael@0:     mesh.width = Math.max(w, mesh.width);
michael@0:     mesh.height = Math.max(h, mesh.height);
michael@0: 
michael@0:     // check if we need to save the currently active group; this happens after
michael@0:     // we filled all the "slots" in a group or there aren't any remaining nodes
michael@0:     if (((n + 1) % maxGroupNodes === 0) || (n === len - 1)) {
michael@0:       mesh.groups.push({
michael@0:         vertices: vertices,
michael@0:         texCoord: texCoord,
michael@0:         color: color,
michael@0:         stacksIndices: stacksIndices,
michael@0:         wireframeIndices: wireframeIndices
michael@0:       });
michael@0:       mesh.allVertices = mesh.allVertices.concat(vertices);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   self.postMessage(mesh);
michael@0:   close();
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * Utility functions for generating random numbers using the Alea algorithm.
michael@0:  */
michael@0: self.random = {
michael@0: 
michael@0:   /**
michael@0:    * The generator function, automatically created with seed 0.
michael@0:    */
michael@0:   _generator: null,
michael@0: 
michael@0:   /**
michael@0:    * Returns a new random number between [0..1)
michael@0:    */
michael@0:   next: function RNG_next()
michael@0:   {
michael@0:     return this._generator();
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * From http://baagoe.com/en/RandomMusings/javascript
michael@0:    * Johannes Baagoe <baagoe@baagoe.com>, 2010
michael@0:    *
michael@0:    * Seeds a random generator function with a set of passed arguments.
michael@0:    */
michael@0:   seed: function RNG_seed()
michael@0:   {
michael@0:     let s0 = 0;
michael@0:     let s1 = 0;
michael@0:     let s2 = 0;
michael@0:     let c = 1;
michael@0: 
michael@0:     if (arguments.length === 0) {
michael@0:       return this.seed(+new Date());
michael@0:     } else {
michael@0:       s0 = this.mash(" ");
michael@0:       s1 = this.mash(" ");
michael@0:       s2 = this.mash(" ");
michael@0: 
michael@0:       for (let i = 0, len = arguments.length; i < len; i++) {
michael@0:         s0 -= this.mash(arguments[i]);
michael@0:         if (s0 < 0) {
michael@0:           s0 += 1;
michael@0:         }
michael@0:         s1 -= this.mash(arguments[i]);
michael@0:         if (s1 < 0) {
michael@0:           s1 += 1;
michael@0:         }
michael@0:         s2 -= this.mash(arguments[i]);
michael@0:         if (s2 < 0) {
michael@0:           s2 += 1;
michael@0:         }
michael@0:       }
michael@0: 
michael@0:       let random = function() {
michael@0:         let t = 2091639 * s0 + c * 2.3283064365386963e-10; // 2^-32
michael@0:         s0 = s1;
michael@0:         s1 = s2;
michael@0:         return (s2 = t - (c = t | 0));
michael@0:       };
michael@0:       random.uint32 = function() {
michael@0:         return random() * 0x100000000; // 2^32
michael@0:       };
michael@0:       random.fract53 = function() {
michael@0:         return random() +
michael@0:               (random() * 0x200000 | 0) * 1.1102230246251565e-16; // 2^-53
michael@0:       };
michael@0:       return (this._generator = random);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * From http://baagoe.com/en/RandomMusings/javascript
michael@0:    * Johannes Baagoe <baagoe@baagoe.com>, 2010
michael@0:    */
michael@0:   mash: function RNG_mash(data)
michael@0:   {
michael@0:     let h, n = 0xefc8249d;
michael@0: 
michael@0:     for (let i = 0, data = data.toString(), len = data.length; i < len; i++) {
michael@0:       n += data.charCodeAt(i);
michael@0:       h = 0.02519603282416938 * n;
michael@0:       n = h >>> 0;
michael@0:       h -= n;
michael@0:       h *= n;
michael@0:       n = h >>> 0;
michael@0:       h -= n;
michael@0:       n += h * 0x100000000; // 2^32
michael@0:     }
michael@0:     return (n >>> 0) * 2.3283064365386963e-10; // 2^-32
michael@0:   }
michael@0: };