1 | /* Copyright (c) 2006-2010 by OpenLayers Contributors (see authors.txt for |
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2 | * full list of contributors). Published under the Clear BSD license. |
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3 | * See http://svn.openlayers.org/trunk/openlayers/license.txt for the |
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4 | * full text of the license. */ |
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5 | |
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6 | |
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7 | /** |
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8 | * @requires OpenLayers/Map.js |
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9 | * @requires OpenLayers/Projection.js |
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10 | */ |
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11 | |
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12 | /** |
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13 | * Class: OpenLayers.Layer |
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14 | */ |
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15 | OpenLayers.Layer = OpenLayers.Class({ |
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16 | |
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17 | /** |
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18 | * APIProperty: id |
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19 | * {String} |
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20 | */ |
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21 | id: null, |
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22 | |
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23 | /** |
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24 | * APIProperty: name |
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25 | * {String} |
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26 | */ |
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27 | name: null, |
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28 | |
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29 | /** |
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30 | * APIProperty: div |
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31 | * {DOMElement} |
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32 | */ |
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33 | div: null, |
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34 | |
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35 | /** |
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36 | * Property: opacity |
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37 | * {Float} The layer's opacity. Float number between 0.0 and 1.0. |
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38 | */ |
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39 | opacity: null, |
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40 | |
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41 | /** |
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42 | * APIProperty: alwaysInRange |
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43 | * {Boolean} If a layer's display should not be scale-based, this should |
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44 | * be set to true. This will cause the layer, as an overlay, to always |
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45 | * be 'active', by always returning true from the calculateInRange() |
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46 | * function. |
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47 | * |
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48 | * If not explicitly specified for a layer, its value will be |
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49 | * determined on startup in initResolutions() based on whether or not |
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50 | * any scale-specific properties have been set as options on the |
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51 | * layer. If no scale-specific options have been set on the layer, we |
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52 | * assume that it should always be in range. |
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53 | * |
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54 | * See #987 for more info. |
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55 | */ |
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56 | alwaysInRange: null, |
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57 | |
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58 | /** |
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59 | * Constant: EVENT_TYPES |
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60 | * {Array(String)} Supported application event types. Register a listener |
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61 | * for a particular event with the following syntax: |
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62 | * (code) |
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63 | * layer.events.register(type, obj, listener); |
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64 | * (end) |
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65 | * |
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66 | * Listeners will be called with a reference to an event object. The |
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67 | * properties of this event depends on exactly what happened. |
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68 | * |
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69 | * All event objects have at least the following properties: |
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70 | * object - {Object} A reference to layer.events.object. |
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71 | * element - {DOMElement} A reference to layer.events.element. |
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72 | * |
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73 | * Supported map event types: |
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74 | * loadstart - Triggered when layer loading starts. |
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75 | * loadend - Triggered when layer loading ends. |
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76 | * loadcancel - Triggered when layer loading is canceled. |
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77 | * visibilitychanged - Triggered when layer visibility is changed. |
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78 | * move - Triggered when layer moves (triggered with every mousemove |
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79 | * during a drag). |
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80 | * moveend - Triggered when layer is done moving, object passed as |
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81 | * argument has a zoomChanged boolean property which tells that the |
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82 | * zoom has changed. |
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83 | */ |
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84 | EVENT_TYPES: ["loadstart", "loadend", "loadcancel", "visibilitychanged", |
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85 | "move", "moveend"], |
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86 | |
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87 | /** |
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88 | * Constant: RESOLUTION_PROPERTIES |
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89 | * {Array} The properties that are used for calculating resolutions |
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90 | * information. |
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91 | */ |
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92 | RESOLUTION_PROPERTIES: [ |
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93 | 'scales', 'resolutions', |
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94 | 'maxScale', 'minScale', |
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95 | 'maxResolution', 'minResolution', |
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96 | 'numZoomLevels', 'maxZoomLevel' |
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97 | ], |
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98 | |
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99 | /** |
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100 | * APIProperty: events |
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101 | * {<OpenLayers.Events>} |
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102 | */ |
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103 | events: null, |
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104 | |
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105 | /** |
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106 | * APIProperty: map |
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107 | * {<OpenLayers.Map>} This variable is set when the layer is added to |
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108 | * the map, via the accessor function setMap(). |
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109 | */ |
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110 | map: null, |
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111 | |
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112 | /** |
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113 | * APIProperty: isBaseLayer |
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114 | * {Boolean} Whether or not the layer is a base layer. This should be set |
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115 | * individually by all subclasses. Default is false |
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116 | */ |
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117 | isBaseLayer: false, |
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118 | |
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119 | /** |
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120 | * Property: alpha |
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121 | * {Boolean} The layer's images have an alpha channel. Default is false. |
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122 | */ |
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123 | alpha: false, |
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124 | |
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125 | /** |
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126 | * APIProperty: displayInLayerSwitcher |
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127 | * {Boolean} Display the layer's name in the layer switcher. Default is |
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128 | * true. |
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129 | */ |
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130 | displayInLayerSwitcher: true, |
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131 | |
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132 | /** |
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133 | * APIProperty: visibility |
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134 | * {Boolean} The layer should be displayed in the map. Default is true. |
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135 | */ |
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136 | visibility: true, |
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137 | |
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138 | /** |
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139 | * APIProperty: attribution |
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140 | * {String} Attribution string, displayed when an |
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141 | * <OpenLayers.Control.Attribution> has been added to the map. |
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142 | */ |
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143 | attribution: null, |
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144 | |
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145 | /** |
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146 | * Property: inRange |
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147 | * {Boolean} The current map resolution is within the layer's min/max |
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148 | * range. This is set in <OpenLayers.Map.setCenter> whenever the zoom |
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149 | * changes. |
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150 | */ |
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151 | inRange: false, |
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152 | |
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153 | /** |
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154 | * Propery: imageSize |
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155 | * {<OpenLayers.Size>} For layers with a gutter, the image is larger than |
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156 | * the tile by twice the gutter in each dimension. |
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157 | */ |
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158 | imageSize: null, |
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159 | |
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160 | /** |
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161 | * Property: imageOffset |
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162 | * {<OpenLayers.Pixel>} For layers with a gutter, the image offset |
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163 | * represents displacement due to the gutter. |
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164 | */ |
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165 | imageOffset: null, |
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166 | |
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167 | // OPTIONS |
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168 | |
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169 | /** |
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170 | * Property: options |
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171 | * {Object} An optional object whose properties will be set on the layer. |
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172 | * Any of the layer properties can be set as a property of the options |
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173 | * object and sent to the constructor when the layer is created. |
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174 | */ |
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175 | options: null, |
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176 | |
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177 | /** |
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178 | * APIProperty: eventListeners |
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179 | * {Object} If set as an option at construction, the eventListeners |
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180 | * object will be registered with <OpenLayers.Events.on>. Object |
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181 | * structure must be a listeners object as shown in the example for |
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182 | * the events.on method. |
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183 | */ |
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184 | eventListeners: null, |
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185 | |
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186 | /** |
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187 | * APIProperty: gutter |
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188 | * {Integer} Determines the width (in pixels) of the gutter around image |
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189 | * tiles to ignore. By setting this property to a non-zero value, |
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190 | * images will be requested that are wider and taller than the tile |
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191 | * size by a value of 2 x gutter. This allows artifacts of rendering |
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192 | * at tile edges to be ignored. Set a gutter value that is equal to |
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193 | * half the size of the widest symbol that needs to be displayed. |
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194 | * Defaults to zero. Non-tiled layers always have zero gutter. |
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195 | */ |
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196 | gutter: 0, |
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197 | |
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198 | /** |
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199 | * APIProperty: projection |
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200 | * {<OpenLayers.Projection>} or {<String>} Set in the layer options to |
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201 | * override the default projection string this layer - also set maxExtent, |
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202 | * maxResolution, and units if appropriate. Can be either a string or |
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203 | * an <OpenLayers.Projection> object when created -- will be converted |
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204 | * to an object when setMap is called if a string is passed. |
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205 | */ |
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206 | projection: null, |
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207 | |
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208 | /** |
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209 | * APIProperty: units |
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210 | * {String} The layer map units. Defaults to 'degrees'. Possible values |
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211 | * are 'degrees' (or 'dd'), 'm', 'ft', 'km', 'mi', 'inches'. |
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212 | */ |
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213 | units: null, |
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214 | |
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215 | /** |
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216 | * APIProperty: scales |
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217 | * {Array} An array of map scales in descending order. The values in the |
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218 | * array correspond to the map scale denominator. Note that these |
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219 | * values only make sense if the display (monitor) resolution of the |
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220 | * client is correctly guessed by whomever is configuring the |
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221 | * application. In addition, the units property must also be set. |
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222 | * Use <resolutions> instead wherever possible. |
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223 | */ |
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224 | scales: null, |
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225 | |
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226 | /** |
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227 | * APIProperty: resolutions |
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228 | * {Array} A list of map resolutions (map units per pixel) in descending |
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229 | * order. If this is not set in the layer constructor, it will be set |
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230 | * based on other resolution related properties (maxExtent, |
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231 | * maxResolution, maxScale, etc.). |
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232 | */ |
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233 | resolutions: null, |
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234 | |
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235 | /** |
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236 | * APIProperty: maxExtent |
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237 | * {<OpenLayers.Bounds>} The center of these bounds will not stray outside |
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238 | * of the viewport extent during panning. In addition, if |
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239 | * <displayOutsideMaxExtent> is set to false, data will not be |
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240 | * requested that falls completely outside of these bounds. |
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241 | */ |
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242 | maxExtent: null, |
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243 | |
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244 | /** |
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245 | * APIProperty: minExtent |
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246 | * {<OpenLayers.Bounds>} |
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247 | */ |
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248 | minExtent: null, |
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249 | |
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250 | /** |
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251 | * APIProperty: maxResolution |
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252 | * {Float} Default max is 360 deg / 256 px, which corresponds to |
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253 | * zoom level 0 on gmaps. Specify a different value in the layer |
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254 | * options if you are not using a geographic projection and |
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255 | * displaying the whole world. |
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256 | */ |
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257 | maxResolution: null, |
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258 | |
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259 | /** |
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260 | * APIProperty: minResolution |
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261 | * {Float} |
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262 | */ |
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263 | minResolution: null, |
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264 | |
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265 | /** |
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266 | * APIProperty: numZoomLevels |
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267 | * {Integer} |
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268 | */ |
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269 | numZoomLevels: null, |
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270 | |
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271 | /** |
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272 | * APIProperty: minScale |
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273 | * {Float} |
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274 | */ |
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275 | minScale: null, |
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276 | |
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277 | /** |
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278 | * APIProperty: maxScale |
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279 | * {Float} |
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280 | */ |
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281 | maxScale: null, |
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282 | |
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283 | /** |
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284 | * APIProperty: displayOutsideMaxExtent |
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285 | * {Boolean} Request map tiles that are completely outside of the max |
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286 | * extent for this layer. Defaults to false. |
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287 | */ |
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288 | displayOutsideMaxExtent: false, |
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289 | |
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290 | /** |
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291 | * APIProperty: wrapDateLine |
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292 | * {Boolean} #487 for more info. |
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293 | */ |
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294 | wrapDateLine: false, |
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295 | |
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296 | /** |
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297 | * APIProperty: transitionEffect |
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298 | * {String} The transition effect to use when the map is panned or |
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299 | * zoomed. |
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300 | * |
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301 | * There are currently two supported values: |
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302 | * - *null* No transition effect (the default). |
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303 | * - *resize* Existing tiles are resized on zoom to provide a visual |
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304 | * effect of the zoom having taken place immediately. As the |
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305 | * new tiles become available, they are drawn over top of the |
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306 | * resized tiles. |
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307 | */ |
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308 | transitionEffect: null, |
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309 | |
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310 | /** |
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311 | * Property: SUPPORTED_TRANSITIONS |
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312 | * {Array} An immutable (that means don't change it!) list of supported |
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313 | * transitionEffect values. |
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314 | */ |
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315 | SUPPORTED_TRANSITIONS: ['resize'], |
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316 | |
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317 | /** |
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318 | * Property: metadata |
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319 | * {Object} This object can be used to store additional information on a |
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320 | * layer object. |
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321 | */ |
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322 | metadata: {}, |
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323 | |
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324 | /** |
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325 | * Constructor: OpenLayers.Layer |
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326 | * |
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327 | * Parameters: |
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328 | * name - {String} The layer name |
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329 | * options - {Object} Hashtable of extra options to tag onto the layer |
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330 | */ |
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331 | initialize: function(name, options) { |
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332 | |
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333 | this.addOptions(options); |
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334 | |
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335 | this.name = name; |
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336 | |
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337 | if (this.id == null) { |
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338 | |
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339 | this.id = OpenLayers.Util.createUniqueID(this.CLASS_NAME + "_"); |
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340 | |
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341 | this.div = OpenLayers.Util.createDiv(this.id); |
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342 | this.div.style.width = "100%"; |
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343 | this.div.style.height = "100%"; |
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344 | this.div.dir = "ltr"; |
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345 | |
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346 | this.events = new OpenLayers.Events(this, this.div, |
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347 | this.EVENT_TYPES); |
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348 | if(this.eventListeners instanceof Object) { |
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349 | this.events.on(this.eventListeners); |
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350 | } |
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351 | |
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352 | } |
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353 | |
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354 | if (this.wrapDateLine) { |
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355 | this.displayOutsideMaxExtent = true; |
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356 | } |
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357 | }, |
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358 | |
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359 | /** |
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360 | * Method: destroy |
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361 | * Destroy is a destructor: this is to alleviate cyclic references which |
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362 | * the Javascript garbage cleaner can not take care of on its own. |
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363 | * |
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364 | * Parameters: |
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365 | * setNewBaseLayer - {Boolean} Set a new base layer when this layer has |
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366 | * been destroyed. Default is true. |
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367 | */ |
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368 | destroy: function(setNewBaseLayer) { |
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369 | if (setNewBaseLayer == null) { |
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370 | setNewBaseLayer = true; |
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371 | } |
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372 | if (this.map != null) { |
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373 | this.map.removeLayer(this, setNewBaseLayer); |
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374 | } |
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375 | this.projection = null; |
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376 | this.map = null; |
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377 | this.name = null; |
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378 | this.div = null; |
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379 | this.options = null; |
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380 | |
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381 | if (this.events) { |
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382 | if(this.eventListeners) { |
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383 | this.events.un(this.eventListeners); |
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384 | } |
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385 | this.events.destroy(); |
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386 | } |
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387 | this.eventListeners = null; |
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388 | this.events = null; |
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389 | }, |
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390 | |
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391 | /** |
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392 | * Method: clone |
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393 | * |
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394 | * Parameters: |
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395 | * obj - {<OpenLayers.Layer>} The layer to be cloned |
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396 | * |
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397 | * Returns: |
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398 | * {<OpenLayers.Layer>} An exact clone of this <OpenLayers.Layer> |
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399 | */ |
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400 | clone: function (obj) { |
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401 | |
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402 | if (obj == null) { |
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403 | obj = new OpenLayers.Layer(this.name, this.getOptions()); |
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404 | } |
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405 | |
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406 | // catch any randomly tagged-on properties |
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407 | OpenLayers.Util.applyDefaults(obj, this); |
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408 | |
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409 | // a cloned layer should never have its map property set |
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410 | // because it has not been added to a map yet. |
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411 | obj.map = null; |
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412 | |
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413 | return obj; |
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414 | }, |
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415 | |
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416 | /** |
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417 | * Method: getOptions |
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418 | * Extracts an object from the layer with the properties that were set as |
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419 | * options, but updates them with the values currently set on the |
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420 | * instance. |
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421 | * |
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422 | * Returns: |
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423 | * {Object} the <options> of the layer, representing the current state. |
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424 | */ |
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425 | getOptions: function() { |
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426 | var options = {}; |
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427 | for(var o in this.options) { |
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428 | options[o] = this[o]; |
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429 | } |
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430 | return options; |
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431 | }, |
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432 | |
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433 | /** |
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434 | * APIMethod: setName |
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435 | * Sets the new layer name for this layer. Can trigger a changelayer event |
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436 | * on the map. |
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437 | * |
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438 | * Parameters: |
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439 | * newName - {String} The new name. |
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440 | */ |
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441 | setName: function(newName) { |
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442 | if (newName != this.name) { |
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443 | this.name = newName; |
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444 | if (this.map != null) { |
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445 | this.map.events.triggerEvent("changelayer", { |
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446 | layer: this, |
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447 | property: "name" |
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448 | }); |
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449 | } |
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450 | } |
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451 | }, |
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452 | |
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453 | /** |
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454 | * APIMethod: addOptions |
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455 | * |
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456 | * Parameters: |
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457 | * newOptions - {Object} |
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458 | */ |
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459 | addOptions: function (newOptions) { |
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460 | |
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461 | if (this.options == null) { |
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462 | this.options = {}; |
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463 | } |
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464 | |
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465 | // update our copy for clone |
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466 | OpenLayers.Util.extend(this.options, newOptions); |
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467 | |
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468 | // add new options to this |
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469 | OpenLayers.Util.extend(this, newOptions); |
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470 | |
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471 | // make sure this.projection references a projection object |
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472 | if(typeof this.projection == "string") { |
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473 | this.projection = new OpenLayers.Projection(this.projection); |
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474 | } |
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475 | |
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476 | // get the units from the projection, if we have a projection |
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477 | // and it it has units |
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478 | if(this.projection && this.projection.getUnits()) { |
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479 | this.units = this.projection.getUnits(); |
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480 | } |
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481 | |
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482 | // re-initialize resolutions if necessary, i.e. if any of the |
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483 | // properties of the "properties" array defined below is set |
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484 | // in the new options |
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485 | if(this.map) { |
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486 | var properties = this.RESOLUTION_PROPERTIES.concat( |
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487 | ["projection", "units", "minExtent", "maxExtent"] |
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488 | ); |
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489 | for(var o in newOptions) { |
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490 | if(newOptions.hasOwnProperty(o) && |
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491 | OpenLayers.Util.indexOf(properties, o) >= 0) { |
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492 | |
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493 | this.initResolutions(); |
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494 | break; |
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495 | } |
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496 | } |
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497 | } |
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498 | }, |
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499 | |
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500 | /** |
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501 | * APIMethod: onMapResize |
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502 | * This function can be implemented by subclasses |
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503 | */ |
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504 | onMapResize: function() { |
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505 | //this function can be implemented by subclasses |
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506 | }, |
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507 | |
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508 | /** |
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509 | * APIMethod: redraw |
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510 | * Redraws the layer. Returns true if the layer was redrawn, false if not. |
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511 | * |
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512 | * Returns: |
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513 | * {Boolean} The layer was redrawn. |
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514 | */ |
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515 | redraw: function() { |
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516 | var redrawn = false; |
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517 | if (this.map) { |
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518 | |
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519 | // min/max Range may have changed |
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520 | this.inRange = this.calculateInRange(); |
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521 | |
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522 | // map's center might not yet be set |
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523 | var extent = this.getExtent(); |
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524 | |
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525 | if (extent && this.inRange && this.visibility) { |
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526 | var zoomChanged = true; |
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527 | this.moveTo(extent, zoomChanged, false); |
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528 | this.events.triggerEvent("moveend", |
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529 | {"zoomChanged": zoomChanged}); |
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530 | redrawn = true; |
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531 | } |
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532 | } |
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533 | return redrawn; |
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534 | }, |
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535 | |
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536 | /** |
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537 | * Method: moveTo |
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538 | * |
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539 | * Parameters: |
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540 | * bound - {<OpenLayers.Bounds>} |
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541 | * zoomChanged - {Boolean} Tells when zoom has changed, as layers have to |
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542 | * do some init work in that case. |
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543 | * dragging - {Boolean} |
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544 | */ |
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545 | moveTo:function(bounds, zoomChanged, dragging) { |
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546 | var display = this.visibility; |
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547 | if (!this.isBaseLayer) { |
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548 | display = display && this.inRange; |
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549 | } |
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550 | this.display(display); |
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551 | }, |
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552 | |
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553 | /** |
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554 | * Method: setMap |
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555 | * Set the map property for the layer. This is done through an accessor |
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556 | * so that subclasses can override this and take special action once |
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557 | * they have their map variable set. |
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558 | * |
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559 | * Here we take care to bring over any of the necessary default |
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560 | * properties from the map. |
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561 | * |
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562 | * Parameters: |
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563 | * map - {<OpenLayers.Map>} |
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564 | */ |
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565 | setMap: function(map) { |
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566 | if (this.map == null) { |
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567 | |
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568 | this.map = map; |
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569 | |
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570 | // grab some essential layer data from the map if it hasn't already |
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571 | // been set |
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572 | this.maxExtent = this.maxExtent || this.map.maxExtent; |
---|
573 | this.minExtent = this.minExtent || this.map.minExtent; |
---|
574 | |
---|
575 | this.projection = this.projection || this.map.projection; |
---|
576 | if (typeof this.projection == "string") { |
---|
577 | this.projection = new OpenLayers.Projection(this.projection); |
---|
578 | } |
---|
579 | |
---|
580 | // Check the projection to see if we can get units -- if not, refer |
---|
581 | // to properties. |
---|
582 | this.units = this.projection.getUnits() || |
---|
583 | this.units || this.map.units; |
---|
584 | |
---|
585 | this.initResolutions(); |
---|
586 | |
---|
587 | if (!this.isBaseLayer) { |
---|
588 | this.inRange = this.calculateInRange(); |
---|
589 | var show = ((this.visibility) && (this.inRange)); |
---|
590 | this.div.style.display = show ? "" : "none"; |
---|
591 | } |
---|
592 | |
---|
593 | // deal with gutters |
---|
594 | this.setTileSize(); |
---|
595 | } |
---|
596 | }, |
---|
597 | |
---|
598 | /** |
---|
599 | * Method: afterAdd |
---|
600 | * Called at the end of the map.addLayer sequence. At this point, the map |
---|
601 | * will have a base layer. To be overridden by subclasses. |
---|
602 | */ |
---|
603 | afterAdd: function() { |
---|
604 | }, |
---|
605 | |
---|
606 | /** |
---|
607 | * APIMethod: removeMap |
---|
608 | * Just as setMap() allows each layer the possibility to take a |
---|
609 | * personalized action on being added to the map, removeMap() allows |
---|
610 | * each layer to take a personalized action on being removed from it. |
---|
611 | * For now, this will be mostly unused, except for the EventPane layer, |
---|
612 | * which needs this hook so that it can remove the special invisible |
---|
613 | * pane. |
---|
614 | * |
---|
615 | * Parameters: |
---|
616 | * map - {<OpenLayers.Map>} |
---|
617 | */ |
---|
618 | removeMap: function(map) { |
---|
619 | //to be overridden by subclasses |
---|
620 | }, |
---|
621 | |
---|
622 | /** |
---|
623 | * APIMethod: getImageSize |
---|
624 | * |
---|
625 | * Parameters: |
---|
626 | * bounds - {<OpenLayers.Bounds>} optional tile bounds, can be used |
---|
627 | * by subclasses that have to deal with different tile sizes at the |
---|
628 | * layer extent edges (e.g. Zoomify) |
---|
629 | * |
---|
630 | * Returns: |
---|
631 | * {<OpenLayers.Size>} The size that the image should be, taking into |
---|
632 | * account gutters. |
---|
633 | */ |
---|
634 | getImageSize: function(bounds) { |
---|
635 | return (this.imageSize || this.tileSize); |
---|
636 | }, |
---|
637 | |
---|
638 | /** |
---|
639 | * APIMethod: setTileSize |
---|
640 | * Set the tile size based on the map size. This also sets layer.imageSize |
---|
641 | * and layer.imageOffset for use by Tile.Image. |
---|
642 | * |
---|
643 | * Parameters: |
---|
644 | * size - {<OpenLayers.Size>} |
---|
645 | */ |
---|
646 | setTileSize: function(size) { |
---|
647 | var tileSize = (size) ? size : |
---|
648 | ((this.tileSize) ? this.tileSize : |
---|
649 | this.map.getTileSize()); |
---|
650 | this.tileSize = tileSize; |
---|
651 | if(this.gutter) { |
---|
652 | // layers with gutters need non-null tile sizes |
---|
653 | //if(tileSize == null) { |
---|
654 | // OpenLayers.console.error("Error in layer.setMap() for " + |
---|
655 | // this.name + ": layers with " + |
---|
656 | // "gutters need non-null tile sizes"); |
---|
657 | //} |
---|
658 | this.imageOffset = new OpenLayers.Pixel(-this.gutter, |
---|
659 | -this.gutter); |
---|
660 | this.imageSize = new OpenLayers.Size(tileSize.w + (2*this.gutter), |
---|
661 | tileSize.h + (2*this.gutter)); |
---|
662 | } |
---|
663 | }, |
---|
664 | |
---|
665 | /** |
---|
666 | * APIMethod: getVisibility |
---|
667 | * |
---|
668 | * Returns: |
---|
669 | * {Boolean} The layer should be displayed (if in range). |
---|
670 | */ |
---|
671 | getVisibility: function() { |
---|
672 | return this.visibility; |
---|
673 | }, |
---|
674 | |
---|
675 | /** |
---|
676 | * APIMethod: setVisibility |
---|
677 | * Set the visibility flag for the layer and hide/show & redraw |
---|
678 | * accordingly. Fire event unless otherwise specified |
---|
679 | * |
---|
680 | * Note that visibility is no longer simply whether or not the layer's |
---|
681 | * style.display is set to "block". Now we store a 'visibility' state |
---|
682 | * property on the layer class, this allows us to remember whether or |
---|
683 | * not we *desire* for a layer to be visible. In the case where the |
---|
684 | * map's resolution is out of the layer's range, this desire may be |
---|
685 | * subverted. |
---|
686 | * |
---|
687 | * Parameters: |
---|
688 | * visible - {Boolean} Whether or not to display the layer (if in range) |
---|
689 | */ |
---|
690 | setVisibility: function(visibility) { |
---|
691 | if (visibility != this.visibility) { |
---|
692 | this.visibility = visibility; |
---|
693 | this.display(visibility); |
---|
694 | this.redraw(); |
---|
695 | if (this.map != null) { |
---|
696 | this.map.events.triggerEvent("changelayer", { |
---|
697 | layer: this, |
---|
698 | property: "visibility" |
---|
699 | }); |
---|
700 | } |
---|
701 | this.events.triggerEvent("visibilitychanged"); |
---|
702 | } |
---|
703 | }, |
---|
704 | |
---|
705 | /** |
---|
706 | * APIMethod: display |
---|
707 | * Hide or show the Layer |
---|
708 | * |
---|
709 | * Parameters: |
---|
710 | * display - {Boolean} |
---|
711 | */ |
---|
712 | display: function(display) { |
---|
713 | if (display != (this.div.style.display != "none")) { |
---|
714 | this.div.style.display = (display && this.calculateInRange()) ? "block" : "none"; |
---|
715 | } |
---|
716 | }, |
---|
717 | |
---|
718 | /** |
---|
719 | * APIMethod: calculateInRange |
---|
720 | * |
---|
721 | * Returns: |
---|
722 | * {Boolean} The layer is displayable at the current map's current |
---|
723 | * resolution. Note that if 'alwaysInRange' is true for the layer, |
---|
724 | * this function will always return true. |
---|
725 | */ |
---|
726 | calculateInRange: function() { |
---|
727 | var inRange = false; |
---|
728 | |
---|
729 | if (this.alwaysInRange) { |
---|
730 | inRange = true; |
---|
731 | } else { |
---|
732 | if (this.map) { |
---|
733 | var resolution = this.map.getResolution(); |
---|
734 | inRange = ( (resolution >= this.minResolution) && |
---|
735 | (resolution <= this.maxResolution) ); |
---|
736 | } |
---|
737 | } |
---|
738 | return inRange; |
---|
739 | }, |
---|
740 | |
---|
741 | /** |
---|
742 | * APIMethod: setIsBaseLayer |
---|
743 | * |
---|
744 | * Parameters: |
---|
745 | * isBaseLayer - {Boolean} |
---|
746 | */ |
---|
747 | setIsBaseLayer: function(isBaseLayer) { |
---|
748 | if (isBaseLayer != this.isBaseLayer) { |
---|
749 | this.isBaseLayer = isBaseLayer; |
---|
750 | if (this.map != null) { |
---|
751 | this.map.events.triggerEvent("changebaselayer", { |
---|
752 | layer: this |
---|
753 | }); |
---|
754 | } |
---|
755 | } |
---|
756 | }, |
---|
757 | |
---|
758 | /********************************************************/ |
---|
759 | /* */ |
---|
760 | /* Baselayer Functions */ |
---|
761 | /* */ |
---|
762 | /********************************************************/ |
---|
763 | |
---|
764 | /** |
---|
765 | * Method: initResolutions |
---|
766 | * This method's responsibility is to set up the 'resolutions' array |
---|
767 | * for the layer -- this array is what the layer will use to interface |
---|
768 | * between the zoom levels of the map and the resolution display |
---|
769 | * of the layer. |
---|
770 | * |
---|
771 | * The user has several options that determine how the array is set up. |
---|
772 | * |
---|
773 | * For a detailed explanation, see the following wiki from the |
---|
774 | * openlayers.org homepage: |
---|
775 | * http://trac.openlayers.org/wiki/SettingZoomLevels |
---|
776 | */ |
---|
777 | initResolutions: function() { |
---|
778 | |
---|
779 | // ok we want resolutions, here's our strategy: |
---|
780 | // |
---|
781 | // 1. if resolutions are defined in the layer config, use them |
---|
782 | // 2. else, if scales are defined in the layer config then derive |
---|
783 | // resolutions from these scales |
---|
784 | // 3. else, attempt to calculate resolutions from maxResolution, |
---|
785 | // minResolution, numZoomLevels, maxZoomLevel set in the |
---|
786 | // layer config |
---|
787 | // 4. if we still don't have resolutions, and if resolutions |
---|
788 | // are defined in the same, use them |
---|
789 | // 5. else, if scales are defined in the map then derive |
---|
790 | // resolutions from these scales |
---|
791 | // 6. else, attempt to calculate resolutions from maxResolution, |
---|
792 | // minResolution, numZoomLevels, maxZoomLevel set in the |
---|
793 | // map |
---|
794 | // 7. hope for the best! |
---|
795 | |
---|
796 | var i, len; |
---|
797 | var props = {}, alwaysInRange = true; |
---|
798 | |
---|
799 | // get resolution data from layer config |
---|
800 | // (we also set alwaysInRange in the layer as appropriate) |
---|
801 | for(i=0, len=this.RESOLUTION_PROPERTIES.length; i<len; i++) { |
---|
802 | var p = this.RESOLUTION_PROPERTIES[i]; |
---|
803 | props[p] = this.options[p]; |
---|
804 | if(alwaysInRange && this.options[p]) { |
---|
805 | alwaysInRange = false; |
---|
806 | } |
---|
807 | } |
---|
808 | if(this.alwaysInRange == null) { |
---|
809 | this.alwaysInRange = alwaysInRange; |
---|
810 | } |
---|
811 | |
---|
812 | // if we don't have resolutions then attempt to derive them from scales |
---|
813 | if(props.resolutions == null) { |
---|
814 | props.resolutions = this.resolutionsFromScales(props.scales); |
---|
815 | } |
---|
816 | |
---|
817 | // if we still don't have resolutions then attempt to calculate them |
---|
818 | if(props.resolutions == null) { |
---|
819 | props.resolutions = this.calculateResolutions(props); |
---|
820 | } |
---|
821 | |
---|
822 | // if we couldn't calculate resolutions then we look at we have |
---|
823 | // in the map |
---|
824 | if(props.resolutions == null) { |
---|
825 | for(i=0, len=this.RESOLUTION_PROPERTIES.length; i<len; i++) { |
---|
826 | var p = this.RESOLUTION_PROPERTIES[i]; |
---|
827 | props[p] = this.options[p] != null ? |
---|
828 | this.options[p] : this.map[p]; |
---|
829 | } |
---|
830 | if(props.resolutions == null) { |
---|
831 | props.resolutions = this.resolutionsFromScales(props.scales); |
---|
832 | } |
---|
833 | if(props.resolutions == null) { |
---|
834 | props.resolutions = this.calculateResolutions(props); |
---|
835 | } |
---|
836 | } |
---|
837 | |
---|
838 | // ok, we new need to set properties in the instance |
---|
839 | |
---|
840 | // get maxResolution from the config if it's defined there |
---|
841 | var maxResolution; |
---|
842 | if(this.options.maxResolution && |
---|
843 | this.options.maxResolution !== "auto") { |
---|
844 | maxResolution = this.options.maxResolution; |
---|
845 | } |
---|
846 | if(this.options.minScale) { |
---|
847 | maxResolution = OpenLayers.Util.getResolutionFromScale( |
---|
848 | this.options.minScale, this.units); |
---|
849 | } |
---|
850 | |
---|
851 | // get minResolution from the config if it's defined there |
---|
852 | var minResolution; |
---|
853 | if(this.options.minResolution && |
---|
854 | this.options.minResolution !== "auto") { |
---|
855 | minResolution = this.options.minResolution; |
---|
856 | } |
---|
857 | if(this.options.maxScale) { |
---|
858 | minResolution = OpenLayers.Util.getResolutionFromScale( |
---|
859 | this.options.maxScale, this.units); |
---|
860 | } |
---|
861 | |
---|
862 | if(props.resolutions) { |
---|
863 | |
---|
864 | //sort resolutions array descendingly |
---|
865 | props.resolutions.sort(function(a, b) { |
---|
866 | return (b - a); |
---|
867 | }); |
---|
868 | |
---|
869 | // if we still don't have a maxResolution get it from the |
---|
870 | // resolutions array |
---|
871 | if(!maxResolution) { |
---|
872 | maxResolution = props.resolutions[0]; |
---|
873 | } |
---|
874 | |
---|
875 | // if we still don't have a minResolution get it from the |
---|
876 | // resolutions array |
---|
877 | if(!minResolution) { |
---|
878 | var lastIdx = props.resolutions.length - 1; |
---|
879 | minResolution = props.resolutions[lastIdx]; |
---|
880 | } |
---|
881 | } |
---|
882 | |
---|
883 | this.resolutions = props.resolutions; |
---|
884 | if(this.resolutions) { |
---|
885 | len = this.resolutions.length; |
---|
886 | this.scales = new Array(len); |
---|
887 | for(i=0; i<len; i++) { |
---|
888 | this.scales[i] = OpenLayers.Util.getScaleFromResolution( |
---|
889 | this.resolutions[i], this.units); |
---|
890 | } |
---|
891 | this.numZoomLevels = len; |
---|
892 | } |
---|
893 | this.minResolution = minResolution; |
---|
894 | if(minResolution) { |
---|
895 | this.maxScale = OpenLayers.Util.getScaleFromResolution( |
---|
896 | minResolution, this.units); |
---|
897 | } |
---|
898 | this.maxResolution = maxResolution; |
---|
899 | if(maxResolution) { |
---|
900 | this.minScale = OpenLayers.Util.getScaleFromResolution( |
---|
901 | maxResolution, this.units); |
---|
902 | } |
---|
903 | }, |
---|
904 | |
---|
905 | /** |
---|
906 | * Method: resolutionsFromScales |
---|
907 | * Derive resolutions from scales. |
---|
908 | * |
---|
909 | * Parameters: |
---|
910 | * scales - {Array(Number)} Scales |
---|
911 | * |
---|
912 | * Returns |
---|
913 | * {Array(Number)} Resolutions |
---|
914 | */ |
---|
915 | resolutionsFromScales: function(scales) { |
---|
916 | if(scales == null) { |
---|
917 | return; |
---|
918 | } |
---|
919 | var resolutions, i, len; |
---|
920 | len = scales.length; |
---|
921 | resolutions = new Array(len); |
---|
922 | for(i=0; i<len; i++) { |
---|
923 | resolutions[i] = OpenLayers.Util.getResolutionFromScale( |
---|
924 | scales[i], this.units); |
---|
925 | } |
---|
926 | return resolutions; |
---|
927 | }, |
---|
928 | |
---|
929 | /** |
---|
930 | * Method: calculateResolutions |
---|
931 | * Calculate resolutions based on the provided properties. |
---|
932 | * |
---|
933 | * Parameters: |
---|
934 | * props - {Object} Properties |
---|
935 | * |
---|
936 | * Return: |
---|
937 | * {Array({Number})} Array of resolutions. |
---|
938 | */ |
---|
939 | calculateResolutions: function(props) { |
---|
940 | |
---|
941 | // determine maxResolution |
---|
942 | var maxResolution = props.maxResolution; |
---|
943 | if(props.minScale != null) { |
---|
944 | maxResolution = |
---|
945 | OpenLayers.Util.getResolutionFromScale(props.minScale, |
---|
946 | this.units); |
---|
947 | } else if(maxResolution == "auto" && this.maxExtent != null) { |
---|
948 | var viewSize = this.map.getSize(); |
---|
949 | var wRes = this.maxExtent.getWidth() / viewSize.w; |
---|
950 | var hRes = this.maxExtent.getHeight() / viewSize.h; |
---|
951 | maxResolution = Math.max(wRes, hRes); |
---|
952 | } |
---|
953 | |
---|
954 | // determine minResolution |
---|
955 | var minResolution = props.minResolution; |
---|
956 | if(props.maxScale != null) { |
---|
957 | minResolution = |
---|
958 | OpenLayers.Util.getResolutionFromScale(props.maxScale, |
---|
959 | this.units); |
---|
960 | } else if(props.minResolution == "auto" && this.minExtent != null) { |
---|
961 | var viewSize = this.map.getSize(); |
---|
962 | var wRes = this.minExtent.getWidth() / viewSize.w; |
---|
963 | var hRes = this.minExtent.getHeight()/ viewSize.h; |
---|
964 | minResolution = Math.max(wRes, hRes); |
---|
965 | } |
---|
966 | |
---|
967 | // determine numZoomLevels |
---|
968 | var maxZoomLevel = props.maxZoomLevel; |
---|
969 | var numZoomLevels = props.numZoomLevels; |
---|
970 | if(typeof minResolution === "number" && |
---|
971 | typeof maxResolution === "number" && numZoomLevels === undefined) { |
---|
972 | var ratio = maxResolution / minResolution; |
---|
973 | numZoomLevels = Math.floor(Math.log(ratio) / Math.log(2)) + 1; |
---|
974 | } else if(numZoomLevels === undefined && maxZoomLevel != null) { |
---|
975 | numZoomLevels = maxZoomLevel + 1; |
---|
976 | } |
---|
977 | |
---|
978 | // are we able to calculate resolutions? |
---|
979 | if(typeof numZoomLevels !== "number" || numZoomLevels <= 0 || |
---|
980 | (typeof maxResolution !== "number" && |
---|
981 | typeof minResolution !== "number")) { |
---|
982 | return; |
---|
983 | } |
---|
984 | |
---|
985 | // now we have numZoomLevels and at least one of maxResolution |
---|
986 | // or minResolution, we can populate the resolutions array |
---|
987 | |
---|
988 | var resolutions = new Array(numZoomLevels); |
---|
989 | var base = 2; |
---|
990 | if(typeof minResolution == "number" && |
---|
991 | typeof maxResolution == "number") { |
---|
992 | // if maxResolution and minResolution are set, we calculate |
---|
993 | // the base for exponential scaling that starts at |
---|
994 | // maxResolution and ends at minResolution in numZoomLevels |
---|
995 | // steps. |
---|
996 | base = Math.pow( |
---|
997 | (maxResolution / minResolution), |
---|
998 | (1 / (numZoomLevels - 1)) |
---|
999 | ); |
---|
1000 | } |
---|
1001 | |
---|
1002 | var i; |
---|
1003 | if(typeof maxResolution === "number") { |
---|
1004 | for(i=0; i<numZoomLevels; i++) { |
---|
1005 | resolutions[i] = maxResolution / Math.pow(base, i); |
---|
1006 | } |
---|
1007 | } else { |
---|
1008 | for(i=0; i<numZoomLevels; i++) { |
---|
1009 | resolutions[numZoomLevels - 1 - i] = |
---|
1010 | minResolution * Math.pow(base, i); |
---|
1011 | } |
---|
1012 | } |
---|
1013 | |
---|
1014 | return resolutions; |
---|
1015 | }, |
---|
1016 | |
---|
1017 | /** |
---|
1018 | * APIMethod: getResolution |
---|
1019 | * |
---|
1020 | * Returns: |
---|
1021 | * {Float} The currently selected resolution of the map, taken from the |
---|
1022 | * resolutions array, indexed by current zoom level. |
---|
1023 | */ |
---|
1024 | getResolution: function() { |
---|
1025 | var zoom = this.map.getZoom(); |
---|
1026 | return this.getResolutionForZoom(zoom); |
---|
1027 | }, |
---|
1028 | |
---|
1029 | /** |
---|
1030 | * APIMethod: getExtent |
---|
1031 | * |
---|
1032 | * Returns: |
---|
1033 | * {<OpenLayers.Bounds>} A Bounds object which represents the lon/lat |
---|
1034 | * bounds of the current viewPort. |
---|
1035 | */ |
---|
1036 | getExtent: function() { |
---|
1037 | // just use stock map calculateBounds function -- passing no arguments |
---|
1038 | // means it will user map's current center & resolution |
---|
1039 | // |
---|
1040 | return this.map.calculateBounds(); |
---|
1041 | }, |
---|
1042 | |
---|
1043 | /** |
---|
1044 | * APIMethod: getZoomForExtent |
---|
1045 | * |
---|
1046 | * Parameters: |
---|
1047 | * bounds - {<OpenLayers.Bounds>} |
---|
1048 | * closest - {Boolean} Find the zoom level that most closely fits the |
---|
1049 | * specified bounds. Note that this may result in a zoom that does |
---|
1050 | * not exactly contain the entire extent. |
---|
1051 | * Default is false. |
---|
1052 | * |
---|
1053 | * Returns: |
---|
1054 | * {Integer} The index of the zoomLevel (entry in the resolutions array) |
---|
1055 | * for the passed-in extent. We do this by calculating the ideal |
---|
1056 | * resolution for the given extent (based on the map size) and then |
---|
1057 | * calling getZoomForResolution(), passing along the 'closest' |
---|
1058 | * parameter. |
---|
1059 | */ |
---|
1060 | getZoomForExtent: function(extent, closest) { |
---|
1061 | var viewSize = this.map.getSize(); |
---|
1062 | var idealResolution = Math.max( extent.getWidth() / viewSize.w, |
---|
1063 | extent.getHeight() / viewSize.h ); |
---|
1064 | |
---|
1065 | return this.getZoomForResolution(idealResolution, closest); |
---|
1066 | }, |
---|
1067 | |
---|
1068 | /** |
---|
1069 | * Method: getDataExtent |
---|
1070 | * Calculates the max extent which includes all of the data for the layer. |
---|
1071 | * This function is to be implemented by subclasses. |
---|
1072 | * |
---|
1073 | * Returns: |
---|
1074 | * {<OpenLayers.Bounds>} |
---|
1075 | */ |
---|
1076 | getDataExtent: function () { |
---|
1077 | //to be implemented by subclasses |
---|
1078 | }, |
---|
1079 | |
---|
1080 | /** |
---|
1081 | * APIMethod: getResolutionForZoom |
---|
1082 | * |
---|
1083 | * Parameter: |
---|
1084 | * zoom - {Float} |
---|
1085 | * |
---|
1086 | * Returns: |
---|
1087 | * {Float} A suitable resolution for the specified zoom. |
---|
1088 | */ |
---|
1089 | getResolutionForZoom: function(zoom) { |
---|
1090 | zoom = Math.max(0, Math.min(zoom, this.resolutions.length - 1)); |
---|
1091 | var resolution; |
---|
1092 | if(this.map.fractionalZoom) { |
---|
1093 | var low = Math.floor(zoom); |
---|
1094 | var high = Math.ceil(zoom); |
---|
1095 | resolution = this.resolutions[low] - |
---|
1096 | ((zoom-low) * (this.resolutions[low]-this.resolutions[high])); |
---|
1097 | } else { |
---|
1098 | resolution = this.resolutions[Math.round(zoom)]; |
---|
1099 | } |
---|
1100 | return resolution; |
---|
1101 | }, |
---|
1102 | |
---|
1103 | /** |
---|
1104 | * APIMethod: getZoomForResolution |
---|
1105 | * |
---|
1106 | * Parameters: |
---|
1107 | * resolution - {Float} |
---|
1108 | * closest - {Boolean} Find the zoom level that corresponds to the absolute |
---|
1109 | * closest resolution, which may result in a zoom whose corresponding |
---|
1110 | * resolution is actually smaller than we would have desired (if this |
---|
1111 | * is being called from a getZoomForExtent() call, then this means that |
---|
1112 | * the returned zoom index might not actually contain the entire |
---|
1113 | * extent specified... but it'll be close). |
---|
1114 | * Default is false. |
---|
1115 | * |
---|
1116 | * Returns: |
---|
1117 | * {Integer} The index of the zoomLevel (entry in the resolutions array) |
---|
1118 | * that corresponds to the best fit resolution given the passed in |
---|
1119 | * value and the 'closest' specification. |
---|
1120 | */ |
---|
1121 | getZoomForResolution: function(resolution, closest) { |
---|
1122 | var zoom; |
---|
1123 | if(this.map.fractionalZoom) { |
---|
1124 | var lowZoom = 0; |
---|
1125 | var highZoom = this.resolutions.length - 1; |
---|
1126 | var highRes = this.resolutions[lowZoom]; |
---|
1127 | var lowRes = this.resolutions[highZoom]; |
---|
1128 | var res; |
---|
1129 | for(var i=0, len=this.resolutions.length; i<len; ++i) { |
---|
1130 | res = this.resolutions[i]; |
---|
1131 | if(res >= resolution) { |
---|
1132 | highRes = res; |
---|
1133 | lowZoom = i; |
---|
1134 | } |
---|
1135 | if(res <= resolution) { |
---|
1136 | lowRes = res; |
---|
1137 | highZoom = i; |
---|
1138 | break; |
---|
1139 | } |
---|
1140 | } |
---|
1141 | var dRes = highRes - lowRes; |
---|
1142 | if(dRes > 0) { |
---|
1143 | zoom = lowZoom + ((highRes - resolution) / dRes); |
---|
1144 | } else { |
---|
1145 | zoom = lowZoom; |
---|
1146 | } |
---|
1147 | } else { |
---|
1148 | var diff; |
---|
1149 | var minDiff = Number.POSITIVE_INFINITY; |
---|
1150 | for(var i=0, len=this.resolutions.length; i<len; i++) { |
---|
1151 | if (closest) { |
---|
1152 | diff = Math.abs(this.resolutions[i] - resolution); |
---|
1153 | if (diff > minDiff) { |
---|
1154 | break; |
---|
1155 | } |
---|
1156 | minDiff = diff; |
---|
1157 | } else { |
---|
1158 | if (this.resolutions[i] < resolution) { |
---|
1159 | break; |
---|
1160 | } |
---|
1161 | } |
---|
1162 | } |
---|
1163 | zoom = Math.max(0, i-1); |
---|
1164 | } |
---|
1165 | return zoom; |
---|
1166 | }, |
---|
1167 | |
---|
1168 | /** |
---|
1169 | * APIMethod: getLonLatFromViewPortPx |
---|
1170 | * |
---|
1171 | * Parameters: |
---|
1172 | * viewPortPx - {<OpenLayers.Pixel>} |
---|
1173 | * |
---|
1174 | * Returns: |
---|
1175 | * {<OpenLayers.LonLat>} An OpenLayers.LonLat which is the passed-in |
---|
1176 | * view port <OpenLayers.Pixel>, translated into lon/lat by the layer. |
---|
1177 | */ |
---|
1178 | getLonLatFromViewPortPx: function (viewPortPx) { |
---|
1179 | var lonlat = null; |
---|
1180 | if (viewPortPx != null) { |
---|
1181 | var size = this.map.getSize(); |
---|
1182 | var center = this.map.getCenter(); |
---|
1183 | if (center) { |
---|
1184 | var res = this.map.getResolution(); |
---|
1185 | |
---|
1186 | var delta_x = viewPortPx.x - (size.w / 2); |
---|
1187 | var delta_y = viewPortPx.y - (size.h / 2); |
---|
1188 | |
---|
1189 | lonlat = new OpenLayers.LonLat(center.lon + delta_x * res , |
---|
1190 | center.lat - delta_y * res); |
---|
1191 | |
---|
1192 | if (this.wrapDateLine) { |
---|
1193 | lonlat = lonlat.wrapDateLine(this.maxExtent); |
---|
1194 | } |
---|
1195 | } // else { DEBUG STATEMENT } |
---|
1196 | } |
---|
1197 | return lonlat; |
---|
1198 | }, |
---|
1199 | |
---|
1200 | /** |
---|
1201 | * APIMethod: getViewPortPxFromLonLat |
---|
1202 | * Returns a pixel location given a map location. This method will return |
---|
1203 | * fractional pixel values. |
---|
1204 | * |
---|
1205 | * Parameters: |
---|
1206 | * lonlat - {<OpenLayers.LonLat>} |
---|
1207 | * |
---|
1208 | * Returns: |
---|
1209 | * {<OpenLayers.Pixel>} An <OpenLayers.Pixel> which is the passed-in |
---|
1210 | * <OpenLayers.LonLat>,translated into view port pixels. |
---|
1211 | */ |
---|
1212 | getViewPortPxFromLonLat: function (lonlat) { |
---|
1213 | var px = null; |
---|
1214 | if (lonlat != null) { |
---|
1215 | var resolution = this.map.getResolution(); |
---|
1216 | var extent = this.map.getExtent(); |
---|
1217 | px = new OpenLayers.Pixel( |
---|
1218 | (1/resolution * (lonlat.lon - extent.left)), |
---|
1219 | (1/resolution * (extent.top - lonlat.lat)) |
---|
1220 | ); |
---|
1221 | } |
---|
1222 | return px; |
---|
1223 | }, |
---|
1224 | |
---|
1225 | /** |
---|
1226 | * APIMethod: setOpacity |
---|
1227 | * Sets the opacity for the entire layer (all images) |
---|
1228 | * |
---|
1229 | * Parameter: |
---|
1230 | * opacity - {Float} |
---|
1231 | */ |
---|
1232 | setOpacity: function(opacity) { |
---|
1233 | if (opacity != this.opacity) { |
---|
1234 | this.opacity = opacity; |
---|
1235 | for(var i=0, len=this.div.childNodes.length; i<len; ++i) { |
---|
1236 | var element = this.div.childNodes[i].firstChild; |
---|
1237 | OpenLayers.Util.modifyDOMElement(element, null, null, null, |
---|
1238 | null, null, null, opacity); |
---|
1239 | } |
---|
1240 | if (this.map != null) { |
---|
1241 | this.map.events.triggerEvent("changelayer", { |
---|
1242 | layer: this, |
---|
1243 | property: "opacity" |
---|
1244 | }); |
---|
1245 | } |
---|
1246 | } |
---|
1247 | }, |
---|
1248 | |
---|
1249 | /** |
---|
1250 | * Method: getZIndex |
---|
1251 | * |
---|
1252 | * Returns: |
---|
1253 | * {Integer} the z-index of this layer |
---|
1254 | */ |
---|
1255 | getZIndex: function () { |
---|
1256 | return this.div.style.zIndex; |
---|
1257 | }, |
---|
1258 | |
---|
1259 | /** |
---|
1260 | * Method: setZIndex |
---|
1261 | * |
---|
1262 | * Parameters: |
---|
1263 | * zIndex - {Integer} |
---|
1264 | */ |
---|
1265 | setZIndex: function (zIndex) { |
---|
1266 | this.div.style.zIndex = zIndex; |
---|
1267 | }, |
---|
1268 | |
---|
1269 | /** |
---|
1270 | * Method: adjustBounds |
---|
1271 | * This function will take a bounds, and if wrapDateLine option is set |
---|
1272 | * on the layer, it will return a bounds which is wrapped around the |
---|
1273 | * world. We do not wrap for bounds which *cross* the |
---|
1274 | * maxExtent.left/right, only bounds which are entirely to the left |
---|
1275 | * or entirely to the right. |
---|
1276 | * |
---|
1277 | * Parameters: |
---|
1278 | * bounds - {<OpenLayers.Bounds>} |
---|
1279 | */ |
---|
1280 | adjustBounds: function (bounds) { |
---|
1281 | |
---|
1282 | if (this.gutter) { |
---|
1283 | // Adjust the extent of a bounds in map units by the |
---|
1284 | // layer's gutter in pixels. |
---|
1285 | var mapGutter = this.gutter * this.map.getResolution(); |
---|
1286 | bounds = new OpenLayers.Bounds(bounds.left - mapGutter, |
---|
1287 | bounds.bottom - mapGutter, |
---|
1288 | bounds.right + mapGutter, |
---|
1289 | bounds.top + mapGutter); |
---|
1290 | } |
---|
1291 | |
---|
1292 | if (this.wrapDateLine) { |
---|
1293 | // wrap around the date line, within the limits of rounding error |
---|
1294 | var wrappingOptions = { |
---|
1295 | 'rightTolerance':this.getResolution() |
---|
1296 | }; |
---|
1297 | bounds = bounds.wrapDateLine(this.maxExtent, wrappingOptions); |
---|
1298 | |
---|
1299 | } |
---|
1300 | return bounds; |
---|
1301 | }, |
---|
1302 | |
---|
1303 | CLASS_NAME: "OpenLayers.Layer" |
---|
1304 | }); |
---|