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Merge pull request #2079 from tschaub/view-options

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Support zoom and resolution constrained views.
This commit is contained in:
Tim Schaub
2014-05-16 11:26:09 -06:00
parent 6185005c3f 3793f33acf
commit e17c8c79f9
6 changed files with 429 additions and 34 deletions
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8
src/ol/ol.js
View File

@@ -16,11 +16,19 @@ ol.BUFFER_REPLACE_UNUSED_ENTRIES_WITH_NANS = goog.DEBUG;
/**
* TODO: rename this to something having to do with tile grids
* see https://github.com/openlayers/ol3/issues/2076
* @define {number} Default maximum zoom for default tile grids.
*/
ol.DEFAULT_MAX_ZOOM = 42;
/**
* @define {number} Default min zoom level for the map view. Default is `0`.
*/
ol.DEFAULT_MIN_ZOOM = 0;
/**
* @define {number} Default high water mark.
*/

94
src/ol/view2d.js
View File

@@ -116,6 +116,12 @@ ol.View2D = function(opt_options) {
*/
this.minResolution_ = resolutionConstraintInfo.minResolution;
/**
* @private
* @type {number}
*/
this.minZoom_ = resolutionConstraintInfo.minZoom;
var centerConstraint = ol.View2D.createCenterConstraint_(options);
var resolutionConstraint = resolutionConstraintInfo.constraint;
var rotationConstraint = ol.View2D.createRotationConstraint_(options);
@@ -131,7 +137,7 @@ ol.View2D = function(opt_options) {
values[ol.View2DProperty.RESOLUTION] = options.resolution;
} else if (goog.isDef(options.zoom)) {
values[ol.View2DProperty.RESOLUTION] = this.constrainResolution(
this.maxResolution_, options.zoom);
this.maxResolution_, options.zoom - this.minZoom_);
}
values[ol.View2DProperty.ROTATION] =
goog.isDef(options.rotation) ? options.rotation : 0;
@@ -396,7 +402,7 @@ ol.View2D.prototype.getView3D = function() {
* @todo api
*/
ol.View2D.prototype.getZoom = function() {
var zoom;
var offset;
var resolution = this.getResolution();
if (goog.isDef(resolution)) {
@@ -404,14 +410,14 @@ ol.View2D.prototype.getZoom = function() {
do {
res = this.constrainResolution(this.maxResolution_, z);
if (res == resolution) {
zoom = z;
offset = z;
break;
}
++z;
} while (res > this.minResolution_);
}
return zoom;
return goog.isDef(offset) ? this.minZoom_ + offset : offset;
};
@@ -621,7 +627,8 @@ goog.exportProperty(
* @todo api
*/
ol.View2D.prototype.setZoom = function(zoom) {
var resolution = this.constrainResolution(this.maxResolution_, zoom, 0);
var resolution = this.constrainResolution(
this.maxResolution_, zoom - this.minZoom_, 0);
this.setResolution(resolution);
};
@@ -650,6 +657,21 @@ ol.View2D.createResolutionConstraint_ = function(options) {
var resolutionConstraint;
var maxResolution;
var minResolution;
// TODO: move these to be ol constants
// see https://github.com/openlayers/ol3/issues/2076
var defaultMaxZoom = 28;
var defaultZoomFactor = 2;
var minZoom = goog.isDef(options.minZoom) ?
options.minZoom : ol.DEFAULT_MIN_ZOOM;
var maxZoom = goog.isDef(options.maxZoom) ?
options.maxZoom : defaultMaxZoom;
var zoomFactor = goog.isDef(options.zoomFactor) ?
options.zoomFactor : defaultZoomFactor;
if (goog.isDef(options.resolutions)) {
var resolutions = options.resolutions;
maxResolution = resolutions[0];
@@ -657,33 +679,53 @@ ol.View2D.createResolutionConstraint_ = function(options) {
resolutionConstraint = ol.ResolutionConstraint.createSnapToResolutions(
resolutions);
} else {
// calculate the default min and max resolution
var projection = options.projection;
var extent = ol.proj.createProjection(projection, 'EPSG:3857').getExtent();
var size = goog.isNull(extent) ?
// use an extent that can fit the whole world if need be
360 * ol.proj.METERS_PER_UNIT[ol.proj.Units.DEGREES] /
ol.proj.METERS_PER_UNIT[projection.getUnits()] :
Math.max(ol.extent.getWidth(extent), ol.extent.getHeight(extent));
var defaultMaxResolution = size / ol.DEFAULT_TILE_SIZE / Math.pow(
defaultZoomFactor, ol.DEFAULT_MIN_ZOOM);
var defaultMinResolution = defaultMaxResolution / Math.pow(
defaultZoomFactor, defaultMaxZoom - ol.DEFAULT_MIN_ZOOM);
// user provided maxResolution takes precedence
maxResolution = options.maxResolution;
if (!goog.isDef(maxResolution)) {
var projection = options.projection;
var projectionExtent = ol.proj.createProjection(projection, 'EPSG:3857')
.getExtent();
var size = goog.isNull(projectionExtent) ?
// use an extent that can fit the whole world if need be
360 * ol.proj.METERS_PER_UNIT[ol.proj.Units.DEGREES] /
ol.proj.METERS_PER_UNIT[projection.getUnits()] :
Math.max(projectionExtent[2] - projectionExtent[0],
projectionExtent[3] - projectionExtent[1]);
maxResolution = size / ol.DEFAULT_TILE_SIZE;
if (goog.isDef(maxResolution)) {
minZoom = 0;
} else {
maxResolution = defaultMaxResolution / Math.pow(zoomFactor, minZoom);
}
var maxZoom = options.maxZoom;
if (!goog.isDef(maxZoom)) {
maxZoom = 28;
// user provided minResolution takes precedence
minResolution = options.minResolution;
if (!goog.isDef(minResolution)) {
if (goog.isDef(options.maxZoom)) {
if (goog.isDef(options.maxResolution)) {
minResolution = maxResolution / Math.pow(zoomFactor, maxZoom);
} else {
minResolution = defaultMaxResolution / Math.pow(zoomFactor, maxZoom);
}
} else {
minResolution = defaultMinResolution;
}
}
var zoomFactor = options.zoomFactor;
if (!goog.isDef(zoomFactor)) {
zoomFactor = 2;
}
minResolution = maxResolution / Math.pow(zoomFactor, maxZoom);
// given discrete zoom levels, minResolution may be different than provided
maxZoom = minZoom + Math.floor(
Math.log(maxResolution / minResolution) / Math.log(zoomFactor));
minResolution = maxResolution / Math.pow(zoomFactor, maxZoom - minZoom);
resolutionConstraint = ol.ResolutionConstraint.createSnapToPower(
zoomFactor, maxResolution, maxZoom);
zoomFactor, maxResolution, maxZoom - minZoom);
}
return {constraint: resolutionConstraint, maxResolution: maxResolution,
minResolution: minResolution};
minResolution: minResolution, minZoom: minZoom};
};