Ok thanks Tim, I had some trouble at first trying to use minResolution/maxResolution... But quickly found out that when you want a layer only visible at a certain "reach", you must choose either scale OR resolution to work with, not both. I was setting maxResolution to 3.527775872778806 but at some point it was given a new value of 35.27775872778806 ( the maxResolution of the baseLayer... ) because I used scales:[xx,xx,xx].
Using resolutions[xx,xx,xx] solved this problem. But, in the end it didn't help with my cluster strategy problem. I still have to hack Cluster.js to make it work properly. Well, in the end I don't understand what I'm doing wrong. Sorry. Alexandre Tim Schaub wrote: > Hey- > > Alexandre Dube wrote: > >> Hi Eric, >> >> Ok, I understand what you mean. But I already set specific scales to >> the vector layer that are supposed to give the same resolutions I need. >> I mean : >> >> Base layer (map) has scales in its options: [ 100000, 50000, 25000, >> 10000, 5000, 2500, 1000, 500, 250, 100] >> Vector layer has scales in its options: [10000, 5000, 2500, 1000, 500, >> 250, 100] >> >> So I expect the vector layer to have the good corresponding >> resolutions, but it hasn't. Maybe that is the issue. Any thoughts ? >> > > Only the resolutions in your base layer are respected. Individual > resolution values on all overlay layers are ignored. When your map > changes resolution, layer.calculateInRange is called for each overlay > layer. If this returns false, the layer is not displayed. > > The layer.calculateInRange method checks layer.minResolution and > layer.maxResolution. If map.getResolution returns a value that is > between the min/max for the layer (inclusive), calculateInRange returns > true. (The exception to this is when layer.alwaysInRange is true.) > > If you are encountering a situation where calculateInRange does not > return the appropriate value, or if you think the precision in the scale > to resolution conversion is not consistent, please start a new thread > (this has nothing to do with vector layers or the cluster strategy). > > Tim > > >> Alexandre >> >> Eric Lemoine wrote: >> >>> Hi Alexandre >>> >>> If you want your vector layer to be visible only for a subset of the >>> base layer's resolutions you should set maxResolution and/or >>> minResolution in your vector layer options. >>> >>> If you pass an array of resolutions to the vector layer, you can end >>> up with vectorlayer.resolutions[i] != baselayer.resolutions[i], where >>> i is any index of the vector layer's resolutions array. >>> >>> And I think you are hitting the above case, which is making the >>> cluster strategy doesn't behave as you expect it to. >>> >>> So I don't see anything wrong with the cluster strategy relying on >>> this.layer.getResolution. >>> >>> I'd really like to hear what others think about that. >>> >>> Cheers, >>> >>> Eric >>> >>> 2008/11/7, Alexandre Dube <[EMAIL PROTECTED]>: >>> >>> >>>> Hi devs, >>>> >>>> I got a problem using the cluster strategy. At first, it didn't >>>> seemed to work at all. I always got the same number of feature with or >>>> without the cluster strategy applied. After a few search, I found out >>>> the problem was at line 143 : *var* resolution = >>>> *this*.layer.getResolution(); >>>> >>>> I just replaced the line for : *var* resolution = >>>> *this*.layer.map.getResolution(); and it worked. >>>> >>>> The reason is : >>>> >>>> My base layer has 10 fixed scales ( which gives 10 resolutions), from >>>> 0 to 9. My vector layer has only 7, which represents resolutions 3 to 9 >>>> of the base layer's scales, but the vector layer itself has his own >>>> scales array from 0 to 6. So, the line 143 which called resolution 3 >>>> from the base layer calls resolution 3 from the vector layer, which is >>>> wrong ! >>>> >>>> Anyone else noticed this ? >>>> >>>> -- >>>> Alexandre Dubé >>>> Mapgears >>>> www.mapgears.com >>>> >>>> _______________________________________________ >>>> Dev mailing list >>>> Dev@openlayers.org >>>> http://openlayers.org/mailman/listinfo/dev >>>> >>>> >>>> >> > > > -- Alexandre Dubé Mapgears www.mapgears.com _______________________________________________ Dev mailing list Dev@openlayers.org http://openlayers.org/mailman/listinfo/dev
