Re: [UMN_MAPSERVER-USERS] write coordinates into SQL Server

[David Lowther]

William,   Correct me if I am wrong, but what you are after here is how to translate an image click into map coordinates, right?  I suspect that the actual creation of rows in SQL Server with the x, y coordinate values is straightforward.   In order to get the map coordinate from the image click you have to do a bit of legwork since there is no direct method call for this in mapscript (that I am aware of). You are using mapscript_csharp, right? Here’s a bit of code that may help you given that you have a mapextent, image width and height, and image x, y click location:   Public Shared Function ConvertImageToGeo(ByVal imgExtent As GISExtent, ByVal targExtent As GISExtent, ByVal imgPoint As GISPoint) As GISPoint             '//images have 0,0 in upper left corner - effectively switching the orientation of the axis             Dim targPoint As New GISPoint               '//make sure imgpoint is inside imgextent             If Not imgPoint.x <= imgExtent.xMax Or Not imgPoint.x >= imgExtent.xMin Or _                 Not imgPoint.y <= imgExtent.yMax Or Not imgPoint.y >= imgExtent.yMin Then                 Return Nothing             End If               '//precentage along the x and y axis             Dim xPercent, yPercent As Double             xPercent = (imgPoint.x - imgExtent.xMin) / imgExtent.Width             yPercent = (imgPoint.y - imgExtent.yMin) / imgExtent.Height               '//since y axisorientation is backwards - take inverse proportion of yfactor             yPercent = 1 - yPercent               '//calculate offset             Dim targXOffset, targYOffset As Double             targXOffset = targExtent.Width * xPercent             targYOffset = targExtent.Height * yPercent               '//calculate point             targPoint.x = targExtent.xMin + targXOffset             targPoint.y = targExtent.yMin + targYOffset               Return targPoint           End Function     If you are on the client side (_javascript_) you can use this if you populate ImgW, ImgH, MapULX and MapULY beforehand.   function SetMapLoc(imgX, imgY){     var pX = imgX / ImgW;     var pY = imgY / ImgH;       var mapXAdd = MapW * pX;     var mapYAdd = MapH * pY;       MapX = MapULX + mapXAdd;     MapY = MapULY - mapYAdd;         MapX = MapX.toPrecision(8);     MapY = MapY.toPrecision(8); }   Note that neither of these methods is very precise so if you are looking for precision, you’ll need something more sophisticated.   Hope that helps,   David Lowther   Coordinate Solutions, Inc. 501 N.E. 15th Street Oklahoma City, OK 73104 405.246.9396 (Voice) 405.227.0781 (Fax) www.coordinatesolutions.com   From: william paul [mailto:[EMAIL PROTECTED] Sent: Wednesday, November 08, 2006 2:26 PM Subject: write coordinates into SQL Server   Hi:   I would like to create point data by clicking on the map and write the coordinates into SQl Server 2005. It's the opposite of OVF file for creating points from 2 columns from a DBMS (like Sql Server, MySql)   When I click on the map I would like to take automatically the coordinates and record them together with other attributes into a table (Sql Server|) with 2 columns for x and y coordinates   Is it possible to do it?   I am using mapserver 4.10, dBox on IIS server and ASPX with Sql Server 2005     Thank you in advance   William   Sponsored Link For just $24.99/mo., Vonage offers unlimited local and long- distance calling. Sign up now.