![]() |
MapGazer – Using map tools | |
Using marks:
|
Every map has one or more zoom levels, or layers, which can present a view of the map at a different scale. Zoom level 0 is the least detailed (it can show most of the globe as one small image) whereas (for example) 1:25,000 topographical maps are typically presented at zoom level 15 or 16. The scale at a given zoom level differs from the one above or below it by a factor of two. MapGazer provides several Map tools to help you manipulate map layers (for example, to copy maps from different sources to make new composite maps). You can access these map tools either from the main menu (Map→Map tools) or by right-clicking on the map and selecting Map tools from the pop-up menu. Selecting a map tool starts an operation that works in the background. A Progress dialog showing the progress of the operation (with the opportunity to cancel) will be shown. Since these operations might involve Gigabytes of data they cannot be undone – and if cancelled, they might leave partial (but consistent and usable) results. Before using these tools take backups, as appropriate. Maps are generally written using JPEG tiles, but if a source map uses PNG tiles then the target will be written with PNG tiles to preserve transparency (e.g., in Spanish Geological maps). The following tools are available; to avoid conflicts only one can be used at a time:
Note that there is an another tool that can be useful for creating new maps: you can define an Area and then create a subset map that includes the tiles within that Area, at all levels available; for more details, see Using areas. A subset map can then be used as a source or target for any of the operations described above. |
MapGazer and these web pages were written by Mike Cowlishaw; Please send me any corrections, suggestions, etc. | |
All content Copyright © Mike Cowlishaw,
2014–2019, except where marked otherwise. All rights reserved.
The pages here, and the MapGazer program, are for non-commercial
use only.
Privacy policy: the Speleotrove website
records no personal information and sets no ‘cookies’.
However, statistics, etc. might be recorded by the web hosting
service.
This page was last updated on 2019-10-07 by mfc. |