In today’s Web project, we learn how to extend ScaleBarAdornmentLayer to create a custom scale bar that is based on a projection of choice instead of the projection of the map. This can be useful when the displayed projection of the map has highly distortable distances especially at high latitudes such as Spherical Mercator (used by Google Map, Virtual Earth, Yahoo maps etc). Using a scale bar based on distance geometry of the Geodetic (WGS84) projection will give a more accurate result. Note that the CustomScaleBar class is based on MapSuiteCore and can be used in any other versions of MapSuite such as Desktop.

This sample shows how you can suppress and draw exceptions in desktop overlays instead of throwing them. There is a little-known feature in the Map Suite Desktop Edition Overlay class that allows you to draw an exception in the event an exception is thrown during the drawing process. We have a default image we draw in this case; however, you can override this using the DrawExceptionCore method and draw whatever you want. By default we always throw expections, but to start drawing them you can use the Overlay.DrawExceptionMode property.

This project is an introduction on how to handle some basic principles of caching the map in the Desktop edition. Cache has the advantage of reusing existing images of the map when revising areas of the map that have already have been drawn. When in Snap Up mode for Zoom level snapping, cache is very handy. But it is a recommendable practice to not use it when the Zoom Level snapping mode is set to none because it can have the unintended consequence of generating an almost unlimited number of tiles. This project will be followed by other ones showing more advanced features of caching.

This week, we decided to publish in the Code Community the project for Map Suite Explorer. You are already familiar with that free Desktop tool that comes with any edition of Map Suite. It is a basic GIS tool that allows you to view your geographic data and its tabular information. It also allows doing some basic manipulation on your date such as building the spatial index. With the source code at your disposition, you can cut time developing your own application by having at your disposal the code for doing common tasks such as loading, unloading layers, building spatial index, changing styles etc. You will also find interesting the legend and see how you can add, remove, move up and down the different layers. It is by far the most comprehensive project in the Code Community to that date. You will need the reference for MapSuiteDesktop.dll and MapSuiteCore.dll (full or evaluation) to run it.

In today’s project, we show how to have the WinformsMap control in a MDI form. Using an MDI form with a map background can represent a challenge. You will see in this project the technique to display properly a child form on top of the map. You can also notice how the map is accessed from the child form by plotting points on it from the child form.

Starting with version 6.0.113.0, Map Suite includes topology validation capabilities. This Topology Validator sample application makes it simple to visualize and test topology rules. You simply select the case you want to test, use our drawing tools to create the shapes necessary, and then hit the play button to run the test. The error cases are highlighted on the screen and saved to the test, and their Well-Known Text (WKT) is copied to your clipboard. At any time, you can view or edit the WKT which makes up the case. We save our test cases as XML files that contain not only the test case features but also the errors. This makes it a snap for you to share your cases with us or other colleagues.

For more details including a list of topology cases that you can test, see this article or watch the video overview

This sample shows you how to improve drawing accuracy. When drawing a shape on the map it allows you to snap to the closest grid item based on a specified tolerance.

This project demonstrates how to create a web-based map using Microsoft ASP.NET MVC 1.0 and Map Suite Web Edition. To meet the requirements of MVC, we inherit the interface IMapInitializer in the controller, which has a function InitializeMap that is overridden in the controller. We then implement the class “MapInitializerHelper” to initialize the map instance.

This sample shows how you can track zoom in. this sample restrict the track zoom shape when press “Shift Key”. The restricted shape is same resolution (width/height) with map. When set the map’s snapping mode to none, the map zooms to specific zoom level without snapping Select the display area with mouse and shift.