| 1 | /* ***** BEGIN LICENSE BLOCK ***** |
| 2 | * Version: MPL 1.1/GPL 2.0/LGPL 2.1 |
| 3 | * |
| 4 | * The contents of this file are subject to the Mozilla Public License Version |
| 5 | * 1.1 (the "License"); you may not use this file except in compliance with |
| 6 | * the License. You may obtain a copy of the License at |
| 7 | * http://www.mozilla.org/MPL/ |
| 8 | * |
| 9 | * Software distributed under the License is distributed on an "AS IS" basis, |
| 10 | * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License |
| 11 | * for the specific language governing rights and limitations under the |
| 12 | * License. |
| 13 | * |
| 14 | * The Original Code is Lantea mapping/tracking web app. |
| 15 | * |
| 16 | * The Initial Developer of the Original Code is |
| 17 | * Robert Kaiser <kairo@kairo.at>. |
| 18 | * Portions created by the Initial Developer are Copyright (C) 2011 |
| 19 | * the Initial Developer. All Rights Reserved. |
| 20 | * |
| 21 | * Contributor(s): |
| 22 | * Robert Kaiser <kairo@kairo.at> |
| 23 | * |
| 24 | * Alternatively, the contents of this file may be used under the terms of |
| 25 | * either the GNU General Public License Version 2 or later (the "GPL"), or |
| 26 | * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), |
| 27 | * in which case the provisions of the GPL or the LGPL are applicable instead |
| 28 | * of those above. If you wish to allow use of your version of this file only |
| 29 | * under the terms of either the GPL or the LGPL, and not to allow others to |
| 30 | * use your version of this file under the terms of the MPL, indicate your |
| 31 | * decision by deleting the provisions above and replace them with the notice |
| 32 | * and other provisions required by the GPL or the LGPL. If you do not delete |
| 33 | * the provisions above, a recipient may use your version of this file under |
| 34 | * the terms of any one of the MPL, the GPL or the LGPL. |
| 35 | * |
| 36 | * ***** END LICENSE BLOCK ***** */ |
| 37 | |
| 38 | var gCanvas, gContext; |
| 39 | |
| 40 | var gTileSize = 256; |
| 41 | var gMaxZoom = 18; // The minimum is 0. |
| 42 | |
| 43 | //drawMap(); |
| 44 | |
| 45 | var gPos = {x: 35630000.0, // Current position in the map in pixels at the maximum zoom level (18) |
| 46 | y: 23670000.0, // The range is 0-67108864 (2^gMaxZoom * gTileSize) |
| 47 | z: 5.0}; // This can be fractional if we are between zoom levels. |
| 48 | |
| 49 | var gLastMouseX = 0; |
| 50 | var gLastMouseY = 0; |
| 51 | |
| 52 | // Used as an assiciative array. They keys have to be strings, ours will be "xindex,yindex,zindex" e.g. "13,245,12". |
| 53 | var gTiles = {}; |
| 54 | |
| 55 | var gDragging = false; |
| 56 | var gZoomTouchID; |
| 57 | |
| 58 | window.onload = function() { |
| 59 | gCanvas = document.getElementById("map"); |
| 60 | gContext = gCanvas.getContext("2d"); |
| 61 | |
| 62 | gCanvas.addEventListener("mouseup", mapEvHandler, false); |
| 63 | gCanvas.addEventListener("mousemove", mapEvHandler, false); |
| 64 | gCanvas.addEventListener("mousedown", mapEvHandler, false); |
| 65 | gCanvas.addEventListener("mouseout", mapEvHandler, false); |
| 66 | |
| 67 | gCanvas.addEventListener("touchstart", mapEvHandler, false); |
| 68 | gCanvas.addEventListener("touchmove", mapEvHandler, false); |
| 69 | gCanvas.addEventListener("touchend", mapEvHandler, false); |
| 70 | gCanvas.addEventListener("touchcancel", mapEvHandler, false); |
| 71 | gCanvas.addEventListener("touchleave", mapEvHandler, false); |
| 72 | |
| 73 | gCanvas.addEventListener("DOMMouseScroll", mapEvHandler, false); |
| 74 | gCanvas.addEventListener("mousewheel", mapEvHandler, false); |
| 75 | |
| 76 | resizeAndDraw(); |
| 77 | } |
| 78 | |
| 79 | window.onresize = function() { |
| 80 | resizeAndDraw(); |
| 81 | } |
| 82 | |
| 83 | function resizeAndDraw() { |
| 84 | var viewportWidth = window.innerWidth; |
| 85 | var viewportHeight = window.innerHeight; |
| 86 | |
| 87 | var canvasWidth = viewportWidth * 0.98; |
| 88 | var canvasHeight = (viewportHeight-110) * 0.98; |
| 89 | gCanvas.style.position = "fixed"; |
| 90 | gCanvas.width = canvasWidth; |
| 91 | gCanvas.height = canvasHeight; |
| 92 | drawMap(); |
| 93 | } |
| 94 | |
| 95 | function zoomIn() { |
| 96 | if (gPos.z < gMaxZoom) { |
| 97 | gPos.z++; |
| 98 | drawMap(); |
| 99 | } |
| 100 | } |
| 101 | |
| 102 | function zoomOut() { |
| 103 | if (gPos.z > 0) { |
| 104 | gPos.z--; |
| 105 | drawMap(); |
| 106 | } |
| 107 | } |
| 108 | |
| 109 | // A sane mod function that works for negative numbers. |
| 110 | // Returns a % b. |
| 111 | function mod(a, b) { |
| 112 | return ((a % b) + b) % b; |
| 113 | } |
| 114 | |
| 115 | function normaliseIndices(x, y, z) { |
| 116 | return {x: mod(x, Math.pow(2, z)), |
| 117 | y: mod(y, Math.pow(2, z)), |
| 118 | z: z}; |
| 119 | } |
| 120 | |
| 121 | function tileURL(x, y, z) { |
| 122 | var norm = normaliseIndices(x, y, z); |
| 123 | var url = "http://tile.openstreetmap.org/" + norm.z + "/" + norm.x + "/" + norm.y + ".png"; |
| 124 | return url; |
| 125 | } |
| 126 | |
| 127 | // Returns true if the tile is outside the current view. |
| 128 | function isOutsideWindow(t) { |
| 129 | var pos = decodeIndex(t); |
| 130 | var x = pos[0]; |
| 131 | var y = pos[1]; |
| 132 | var z = pos[2]; |
| 133 | |
| 134 | var wid = gCanvas.width * Math.pow(2, gMaxZoom - z); |
| 135 | var ht = gCanvas.height * Math.pow(2, gMaxZoom - z); |
| 136 | |
| 137 | x *= Math.pow(2, gMaxZoom - z); |
| 138 | y *= Math.pow(2, gMaxZoom - z); |
| 139 | |
| 140 | var sz = gTileSize * Math.pow(2, gMaxZoom - z); |
| 141 | if (x > gPos.x + wid / 2 || y > gPos.y + ht / 2 || |
| 142 | x + sz < gPos.x - wid / 2 || y - sz < gPos.y - ht / 2) |
| 143 | return true; |
| 144 | return false; |
| 145 | } |
| 146 | |
| 147 | function encodeIndex(x, y, z) { |
| 148 | var norm = normaliseIndices(x, y, z); |
| 149 | return norm.x + "," + norm.y + "," + norm.z; |
| 150 | } |
| 151 | |
| 152 | function decodeIndex(encodedIdx) { |
| 153 | return encodedIdx.split(",", 3); |
| 154 | } |
| 155 | |
| 156 | function drawMap() { |
| 157 | // Go through all the currently loaded tiles. If we don't want any of them remove them. |
| 158 | // for (t in gTiles) { |
| 159 | // if (isOutsideWindow(t)) |
| 160 | // delete gTiles[t]; |
| 161 | // } |
| 162 | var z = Math.round(gPos.z); |
| 163 | var wid = gCanvas.width * Math.pow(2, gMaxZoom - z); // Width in level 18 pixels. |
| 164 | var ht = gCanvas.height * Math.pow(2, gMaxZoom - z); // Height in level 18 pixels. |
| 165 | var sz = gTileSize * Math.pow(2, gMaxZoom - z); // Tile size in level 18 pixels. |
| 166 | |
| 167 | var xMin = gPos.x - wid / 2; // Corners of the window in level 18 pixels. |
| 168 | var yMin = gPos.y - ht / 2; |
| 169 | var xMax = gPos.x + wid / 2; |
| 170 | var yMax = gPos.y + ht / 2; |
| 171 | |
| 172 | // Go through all the tiles we want. If any of them aren't loaded or being loaded, do so. |
| 173 | for (var x = Math.floor(xMin / sz); x < Math.ceil(xMax / sz); ++x) { |
| 174 | for (var y = Math.floor(yMin / sz); y < Math.ceil(yMax / sz); ++y) { |
| 175 | var xoff = (x * sz - xMin) / Math.pow(2, gMaxZoom - z); |
| 176 | var yoff = (y * sz - yMin) / Math.pow(2, gMaxZoom - z); |
| 177 | var tileKey = encodeIndex(x, y, z); |
| 178 | if (gTiles[tileKey] && gTiles[tileKey].complete) { |
| 179 | // Round here is **CRUICIAL** otherwise the images are filtered and the performance sucks (more than expected). |
| 180 | gContext.drawImage(gTiles[tileKey], Math.round(xoff), Math.round(yoff)); |
| 181 | } |
| 182 | else { |
| 183 | if (!gTiles[tileKey]) { |
| 184 | gTiles[tileKey] = new Image(); |
| 185 | gTiles[tileKey].src = tileURL(x, y, gPos.z); |
| 186 | gTiles[tileKey].onload = function() { |
| 187 | // TODO: Just render this tile where it should be. |
| 188 | // context.drawImage(gTiles[tileKey], Math.round(xoff), Math.round(yoff)); // Doesn't work for some reason. |
| 189 | drawMap(); |
| 190 | } |
| 191 | } |
| 192 | gContext.fillStyle = "#ffffff"; |
| 193 | gContext.fillRect(Math.round(xoff), Math.round(yoff), gTileSize, gTileSize); |
| 194 | } |
| 195 | } |
| 196 | } |
| 197 | } |
| 198 | |
| 199 | var mapEvHandler = { |
| 200 | handleEvent: function(aEvent) { |
| 201 | var touchEvent = aEvent.type.indexOf('touch') != -1; |
| 202 | |
| 203 | // Bail out on unwanted map moves, but not mousewheel events. |
| 204 | if (aEvent.type != "DOMMouseScroll" && aEvent.type != "mousewheel") { |
| 205 | // Bail out if this is neither a touch nor left-click. |
| 206 | if (!touchEvent && aEvent.button != 0) |
| 207 | return; |
| 208 | |
| 209 | // Bail out if the started touch can't be found. |
| 210 | if (touchEvent && zoomstart && |
| 211 | !aEvent.changedTouches.identifiedTouch(gZoomTouchID)) |
| 212 | return; |
| 213 | } |
| 214 | |
| 215 | var coordObj = touchEvent ? |
| 216 | aEvent.changedTouches.identifiedTouch(gZoomTouchID) : |
| 217 | aEvent; |
| 218 | |
| 219 | switch (aEvent.type) { |
| 220 | case "mousedown": |
| 221 | case "touchstart": |
| 222 | if (touchEvent) { |
| 223 | zoomTouchID = aEvent.changedTouches.item(0).identifier; |
| 224 | coordObj = aEvent.changedTouches.identifiedTouch(gZoomTouchID); |
| 225 | } |
| 226 | var x = coordObj.clientX - gCanvas.offsetLeft; |
| 227 | var y = coordObj.clientY - gCanvas.offsetTop; |
| 228 | if (touchEvent || aEvent.button === 0) { |
| 229 | gDragging = true; |
| 230 | } |
| 231 | gLastMouseX = x; |
| 232 | gLastMouseY = y; |
| 233 | break; |
| 234 | case "mousemove": |
| 235 | case "touchmove": |
| 236 | var x = coordObj.clientX - gCanvas.offsetLeft; |
| 237 | var y = coordObj.clientY - gCanvas.offsetTop; |
| 238 | if (gDragging === true) { |
| 239 | var dX = x - gLastMouseX; |
| 240 | var dY = y - gLastMouseY; |
| 241 | gPos.x -= dX * Math.pow(2, gMaxZoom - gPos.z); |
| 242 | gPos.y -= dY * Math.pow(2, gMaxZoom - gPos.z); |
| 243 | drawMap(); |
| 244 | } |
| 245 | gLastMouseX = x; |
| 246 | gLastMouseY = y; |
| 247 | break; |
| 248 | case "mouseup": |
| 249 | case "touchend": |
| 250 | gDragging = false; |
| 251 | break; |
| 252 | case "mouseout": |
| 253 | case "touchcancel": |
| 254 | case "touchleave": |
| 255 | //gDragging = false; |
| 256 | break; |
| 257 | case "DOMMouseScroll": |
| 258 | case "mousewheel": |
| 259 | var delta = 0; |
| 260 | if (aEvent.wheelDelta) { |
| 261 | delta = aEvent.wheelDelta / 120; |
| 262 | if (window.opera) |
| 263 | delta = -delta; |
| 264 | } |
| 265 | else if (aEvent.detail) { |
| 266 | delta = -aEvent.detail / 3; |
| 267 | } |
| 268 | |
| 269 | if (delta > 0) |
| 270 | zoomIn(); |
| 271 | else if (delta < 0) |
| 272 | zoomOut(); |
| 273 | break; |
| 274 | } |
| 275 | } |
| 276 | }; |