Using WMS with OpenLayers - Revision history

DerekEllis: Update WMS services and OpenLayers usages

2021-09-30T23:48:48Z

Update WMS services and OpenLayers usages

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Scottpage at 05:05, 23 December 2013

2013-12-23T05:05:29Z

Scottpage at 05:02, 23 December 2013

2013-12-23T05:02:44Z

Scottpage: /* Access to Testing Example */

2013-12-23T05:02:26Z

Access to Testing Example

Scottpage at 05:01, 23 December 2013

2013-12-23T05:01:37Z

Scottpage at 04:01, 23 December 2013

2013-12-23T04:01:40Z

Scottpage: /* References */

2013-12-23T04:01:21Z

References

Scottpage: /* Resulting Maps */

2013-12-23T03:59:18Z

Resulting Maps

Scottpage at 03:57, 23 December 2013

2013-12-23T03:57:58Z

Scottpage at 03:55, 23 December 2013

2013-12-23T03:55:43Z

← Older revision		Revision as of 05:05, 23 December 2013
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	This tutorial contains a brief outline of WMS layers and OpenLayers, and then descriptions of the methods used to create the maps displayed in Section 4. This includes discussion of the important aspects of the HTML code that generated the resulting maps, as well as projection transformations and the computing of bounding boxes using [http://trac.osgeo.org/proj/ PROJ.4].		This tutorial contains a brief outline of WMS layers and OpenLayers, and then descriptions of the methods used to create the maps displayed in Section 4. This includes discussion of the important aspects of the HTML code that generated the resulting maps, as well as projection transformations and the computing of bounding boxes using [http://trac.osgeo.org/proj/ PROJ.4].


	== Data and Mapping Tools ==		== Data and Mapping Tools ==

← Older revision		Revision as of 05:02, 23 December 2013
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	The OpenLayers WMS example used in this tutorial is available to download [http://dges.carleton.ca/courses/GEOM4008/Student/scottpage/OpenLayersTutorialTest.zip here].		The OpenLayers WMS example used in this tutorial is available to download [http://dges.carleton.ca/courses/GEOM4008/Student/scottpage/OpenLayersTutorialTest.zip here].


	== References ==		== References ==

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 == Access to Testing Example ==
-The OpenLayers WMS testing example used in this tutorial is available to download [http://dges.carleton.ca/courses/GEOM4008/Student/scottpage/OpenLayersTutorialTest.zip here].
+The OpenLayers WMS example used in this tutorial is available to download [http://dges.carleton.ca/courses/GEOM4008/Student/scottpage/OpenLayersTutorialTest.zip here].
 == References ==

@@ Line 248: / Line 248: @@
 ''Figure 3. Displaying the OpenLayers map window of the same area as Figure 2, but at a lesser zoom level.''
+== Access to Testing Example ==
+The OpenLayers WMS testing example used in this tutorial is available to download [http://dges.carleton.ca/courses/GEOM4008/Student/scottpage/OpenLayersTutorialTest.zip here].

← Older revision		Revision as of 04:01, 23 December 2013
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	''Figure 3. Displaying the OpenLayers map window of the same area as Figure 2, but at a lesser zoom level.''		''Figure 3. Displaying the OpenLayers map window of the same area as Figure 2, but at a lesser zoom level.''


	== References ==		== References ==

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 == References ==
-OGC WMS Standards [http://www.opengeospatial.org/standards/wms]
+OGC WMS Standards [http://www.opengeospatial.org/standards/wms http://www.opengeospatial.org/standards/wms]
-OGP Geomatics Committee [http://www.epsg.org/]
+OGP Geomatics Committee [http://www.epsg.org http://www.epsg.org]

← Older revision		Revision as of 03:59, 23 December 2013
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	Figure 2 is the result of the HTML code in Section 3.3. It shows the land cover ~~makeup~~ of the Ottawa area. As this image is rather zoomed in, the land cover, water and roads layers are visible. Figure 3 is included because it shows the Ottawa area at a lower zoom level. From this level, all of the overlay layers are visible, including the populated places layer. This is useful for those who do not know the coordinates of the location they may want to view, or if they want to browse the area surrounding their desired location.		Figure 2 is the result of the HTML code in Section 3.3. It shows the land cover make-up of the Ottawa area. As this image is rather zoomed in, the land cover, water and roads layers are visible. Figure 3 is included because it shows the Ottawa area at a lower zoom level. From this level, all of the overlay layers are visible, including the populated places layer. This is useful for those who do not know the coordinates of the location they may want to view, or if they want to browse the area surrounding their desired location.

← Older revision		Revision as of 03:57, 23 December 2013
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	In order, the numbers refer to: (left limit, bottom limit, right limit, top limit). The left limit and bottom limit numbers give you the (x,y) coordinates of the bottom left corner, and the right limit and top limit give you the (x,y) coordinates of the top right corner. For each of these points, you can use PROJ.4 to computer inverse projections from those coordinates. This will give you new bounding box numbers in unprojected lat/long angular coordinates. If you then want to transform back to a projected coordinate system, you can complete a forward projection transformation, once again generating new bounding box numbers that are new rectangular coordinates. Full documentation regarding how this is done with PROJ.4 can be found at [ftp://ftp.remotesensing.org/proj/proj.4.3.pdf/ ftp://ftp.remotesensing.org/proj/proj.4.3.pdf]		In order, the numbers refer to: (left limit, bottom limit, right limit, top limit). The left limit and bottom limit numbers give you the (x,y) coordinates of the bottom left corner, and the right limit and top limit give you the (x,y) coordinates of the top right corner. For each of these points, you can use PROJ.4 to computer inverse projections from those coordinates. This will give you new bounding box numbers in unprojected lat/long angular coordinates. If you then want to transform back to a projected coordinate system, you can complete a forward projection transformation, once again generating new bounding box numbers that are new rectangular coordinates. Full documentation regarding how this is done with PROJ.4 can be found at [ftp://ftp.remotesensing.org/proj/proj.4.3.pdf/ ftp://ftp.remotesensing.org/proj/proj.4.3.pdf]


	== Resulting Maps ==		== Resulting Maps ==

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   </body>
  </html>
 === Projections ===
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 In order to complete transformations, [http://trac.osgeo.org/proj/ PROJ.4] can be used. It is a Free and Open Source Software (FOSS) library that allows users to perform conversions between cartographic projections. However, it should be noted that the software only transforms from either projected coordinates to unprojected lat/long coordinates, or from unprojected lat/long coordinates to projected coordinates. Thus if you want to transform the data from one projected coordinate system to another, you must undertake a two-step process where you first transform to unprojected lat/long, then transform again to the desired coordinate system.
 === Computing Bounding Boxes ===