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  • How to compensate the flipped coordinate system of core graphics for easy drawing?

    - by mystify
    It's really a pain, but always when I draw an UIImage in -drawRect:, it's upside-down. When I flip the coordinates, the image draws correctly, but at the cost of all other CG functions drawing "wrong" (flipped). What's your strategy when you have to draw images and other things? Is there any rule of thumb how to not get stuck in this problem over and over again? Also, one nasty thing when I flip the y-axis is, that my CGRect from the UIImageView frame is wrong. Instead of the origin appearing at 10,10 upper left as expected, it appears at the bottom. But at the same time, all those normal line drawing functions of CGContext take correct coordinates. drawing a line in -drawRect with origin 10,10 upper left, will really start at upper left. But at the same time that's strange, because core graphics actually has a flipped coordinate system with y 0 at the bottom. So it seems like something is really inconsistent there. Drawing with CGContext functions takes coordinates as "expected" (cmon, nobody thinks in coordinates starting from bottom left, that's silly), while drawing any kind of image still works the "wrong" way. Do you use helper methods to draw images? Or is there anything useful that makes image drawing not a pain in the butt?

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  • How to get the xy coordinate of an image=(0,0) from in the Big box(div)

    - by Farah fathiah
    I have a problem..I'm using visual studio 2008... I want to ask, how to get the xy coordinate of an image=(0,0) from in the Big box(div)??? because when the image is drag to the end of the box it will give me x=8 and y=8...instead of x=0 and y=0... Please help me!!! Tq... Here is the code: $('#dragThis').draggable({ cursor: 'move', // sets the cursor apperance containment: '#box', drag: function() { var offset = $(this).offset(); var xPos = Math.abs(offset.left); var yPos = Math.abs(offset.top); $('#posX').text('x: ' + xPos); $('#posY').text('y: ' + yPos); }, stop: function(event, ui) { // Show dropped position. var Stoppos = $(this).position(); var left = Math.abs(Stoppos.left); var top = Math.abs(Stoppos.top); $('#posX').text('left: ' + left); $('#posY').text('top: ' + top); } }); http://jsfiddle.net/qx5K7/

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  • SQL SERVER – Finding Shortest Distance between Two Shapes using Spatial Data Classes – Ramsetu or Adam’s Bridge

    - by pinaldave
    Recently I was reading excellent blog post by Lenni Lobel on Spatial Database. He has written very interesting function ShortestLineTo in Spatial Data Classes. I really loved this new feature of the finding shortest distance between two shapes in SQL Server. Following is the example which is same as Lenni talk on his blog article . DECLARE @Shape1 geometry = 'POLYGON ((-20 -30, -3 -26, 14 -28, 20 -40, -20 -30))' DECLARE @Shape2 geometry = 'POLYGON ((-18 -20, 0 -10, 4 -12, 10 -20, 2 -22, -18 -20))' SELECT @Shape1 UNION ALL SELECT @Shape2 UNION ALL SELECT @Shape1.ShortestLineTo(@Shape2).STBuffer(.25) GO When you run this script SQL Server finds out the shortest distance between two shapes and draws the line. We are using STBuffer so we can see the connecting line clearly. Now let us modify one of the object and then we see how the connecting shortest line works. DECLARE @Shape1 geometry = 'POLYGON ((-20 -30, -3 -30, 14 -28, 20 -40, -20 -30))' DECLARE @Shape2 geometry = 'POLYGON ((-18 -20, 0 -10, 4 -12, 10 -20, 2 -22, -18 -20))' SELECT @Shape1 UNION ALL SELECT @Shape2 UNION ALL SELECT @Shape1.ShortestLineTo(@Shape2).STBuffer(.25) GO Now once again let us modify one of the script and see how the shortest line to works. DECLARE @Shape1 geometry = 'POLYGON ((-20 -30, -3 -30, 14 -28, 20 -40, -20 -30))' DECLARE @Shape2 geometry = 'POLYGON ((-18 -20, 0 -10, 4 -12, 10 -20, 2 -18, -18 -20))' SELECT @Shape1 UNION ALL SELECT @Shape2 UNION ALL SELECT @Shape1.ShortestLineTo(@Shape2).STBuffer(.25) SELECT @Shape1.STDistance(@Shape2) GO You can see as the objects are changing the shortest lines are moving at appropriate place. I think even though this is very small feature this is really cool know. While I was working on this example, I suddenly thought about distance between Sri Lanka and India. The distance is very short infect it is less than 30 km by sea. I decided to map India and Sri Lanka using spatial data classes. To my surprise the plotted shortest line is the same as Adam’s Bridge or Ramsetu. Adam’s Bridge starts as chain of shoals from the Dhanushkodi tip of India’s Pamban Island and ends at Sri Lanka’s Mannar Island. Geological evidence suggests that this bridge is a former land connection between India and Sri Lanka. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Function, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Spatial Database, SQL Spatial

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  • Coordinates on the top left corner or center of the tile

    - by soimon
    I'm setting up a tile system where every tile has x and y coordinates. Right now I assume that the top left corner of the tile is positioned on it's coordinate on the screen, x = tileX * tileWidth and y = tileY x tileWidth. However, it seems strange that the tile with coordinate (0, 0) is completely drawn in the 'positive' side of the coordinate system as opposed to in the center of the origin. Is it common practice to assume that a coordinate lays in the center of a tile or at the top left corner of a tile? So basically x = tileX x tileWidth or x = tileX x tilewidth - ( tileWidth / 2 )?

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  • SQL SERVER – Validating Spatial Object with IsValidDetailed Function

    - by pinaldave
    What do you prefer – error or warning indicating error may happen with the reason for the error. While writing the previous statement I remember the movie “Minory Report”. This blog post is not about minority report but I will still cover the concept in a single statement “Let us predict the future and prevent the crime which is about to happen in future”. (Please feel free to correct me if I am wrong about the movie concept, I really do not want to hurt your sentiment if you are dedicated fan). Let us switch to the SQL Server world. Spatial data types are interesting concepts. I love writing about spatial data types because it allows me to be creative with shapes (just like toddlers). When working with Spatial Datatypes it is all good when the spatial object works fine. However, when the spatial object has issue or it is created with invalid coordinates it used to give a simple error that there is an issue with the object but did not provide much information. This made it very difficult to debug. If this spatial object was used in the big procedure and while this big procedural error out because of the invalid spatial object, it is indeed very difficult to debug it. I always wished that the more information provided regarding what is the problem with spatial datatype. SQL Server 2012 has introduced the new function IsValidDetailed(). This function has made my life very easy. In simple words this function will check if the spatial object passed is valid or not. If it is valid it will give information that it is valid. If the spatial object is not valid it will return the answer that it is not valid and the reason for the same. This makes it very easy to debug the issue and make the necessary correction. DECLARE @p GEOMETRY = 'Polygon((2 2, 6 6, 4 2, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'Polygon((2 2, 3 3, 4 4, 5 5, 6 6, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'Polygon((2 2, 4 4, 4 2, 2 3, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'CIRCULARSTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'CIRCULARSTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'LINESTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO Here is the resultset of the above query. You can see any valid query and some invalid query. If the query is invalid it also demonstrates the reason along with the error message. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Spatial Database, SQL Spatial

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  • Data Transformation Pipeline

    - by davenewza
    I have create some kind of data pipeline to transform coordinate data into more useful information. Here is the shell of pipeline: public class PositionPipeline { protected List<IPipelineComponent> components; public PositionPipeline() { components = new List<IPipelineComponent>(); } public PositionPipelineEntity Process(Position position) { foreach (var component in components) { position = component.Execute(position); } return position; } public PositionPipeline RegisterComponent(IPipelineComponent component) { components.Add(component); return this; } } Every IPipelineComponent accepts and returns the same type - a PositionPipelineEntity. Code: public interface IPipelineComponent { PositionPipelineEntity Execute(PositionPipelineEntity position); } The PositionPipelineEntity needs to have many properties, many which are unused in certain components and required in others. Some properties will also have become redundant at the end of the pipeline. For example, these components could be executed: TransformCoordinatesComponent: Parse the raw coordinate data into a Coordinate type. DetermineCountryComponent: Determine and stores country code. DetermineOnRoadComponent: Determine and store whether coordinate is on a road. Code: pipeline .RegisterComponent(new TransformCoordinatesComponent()) .RegisterComponent(new DetermineCountryComponent()) .RegisterComponent(new DetermineOnRoadComponent()); pipeline.Process(positionPipelineEntity); The PositionPipelineEntity type: public class PositionPipelineEntity { // Only relevant to the TransformCoordinatesComponent public decimal RawCoordinateLatitude { get; set; } // Only relevant to the TransformCoordinatesComponent public decimal RawCoordinateLongitude { get; set; } // Required by all components after TransformCoordinatesComponent public Coordinate CoordinateLatitude { get; set; } // Required by all components after TransformCoordinatesComponent public Coordinate CoordinateLongitude { get; set; } // Set in DetermineCountryComponent, not required anywhere. // Requires CoordinateLatitude and CoordinateLongitude (TransformCoordinatesComponent) public string CountryCode { get; set; } // Set in DetermineOnRoadComponent, not required anywhere. // Requires CoordinateLatitude and CoordinateLongitude (TransformCoordinatesComponent) public bool OnRoad { get; set; } } Problems: I'm very concerned about the dependency that a component has on properties. The way to solve this would be to create specific types for each component. The problem then is that I cannot chain them together like this. The other problem is the order of components in the pipeline matters. There is some dependency. The current structure does not provide any static or runtime checking for such a thing. Any feedback would be appreciated.

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  • Interpolation between two 3D points?

    - by meds
    I'm working with some splines which define a path a character follows (you can see a gameplay video here to get a better understanding of what's going on: http://www.youtube.com/watch?v=BndobjOiZ6g). Basically the characters 'forward' look direction is set to the 'forward' direction of the spline and when players tilt their phone left and right the character is strafed along its 'right' coordinate. The issue with this is (rather obviously) in performance, interpolating over a spline to find the nearest position and tangent relative to the player is an incredibly costly operation. To get by this I cache a finite number of positions in what I call 'SplineDetails', the class is as follows: public class SplineDetails { public SplineDetails() { Forward = Vector3.forward; Position = Vector3.one * float.MaxValue; Alpha = -1; } public float Alpha; // [0,1] measured along length of spline where 0 is the initial point and 1 is the end point of the spline public Vector3 Position; // the point of the spline at this alpha public Vector3 Forward; // the forward tangent of the spline at this alpha } I populate this with say 30 coordinates and I can give a rough estimate of a coordinate and 'forward' based on a position past in. It's not as accurate but it's much faster. But now I'd like to make the system work better by estimating positions and 'forward' directions by interpolating between two of the cached points though I'm stuck trying to figure out some logic. My first problem is, how can I determine between which two points the object is? Given each point can be placed at different intervals along the spline it could mean that two points in front or behind the object can be closer to the object. The other problem is to figure out the proportion between the two paths it's between, i.e. if there is a point a at coordinate (0,0,0) and point b at coordinate (1,0,0) if the object is at position (0.5,0,0) then the result it should give is '0.5' (as it is equal distance away from point a and point b). That's a simple example, but what if the object is at coordinate (0.5,3,0) for example?

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  • SDL libraries are missing

    - by user287570
    ~/vidmodel/wvsn-model-omnetpp-v4/geometry/Triangle.o ~/vidmodel/wvsn-model-omnetpp-v4/geometry/Polygon.o ~/vidmodel/wvsn-model-omnetpp-v4/geometry/triangulation.o -Wl,--no-as-needed -Wl,--whole-archive -lSDL -lpng -ljpeg -lz -lSDL_image -Wl,--no-whole-archive -L"/home/sreeram/omnetpp-4.2.2/lib/gcc" -L"/home/sreeram/omnetpp-4.2.2/lib" -loppmain -u _cmdenv_lib -Wl,--no-as-needed -loppcmdenv -loppenvir -loppsim -ldl -lstdc++ /usr/bin/ld: cannot find -lSDL /usr/bin/ld: cannot find -lpng /usr/bin/ld: cannot find -ljpeg /usr/bin/ld: cannot find -lSDL_image collect2: ld returned 1 exit can any one please help me

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  • The rightCalloutAccessory button is not shown

    - by Luca
    I try to manage annotations, and to display an info button on the right of the view when a PIN get selected, my relevant code is this: - (MKAnnotationView *)mapView:(MKMapView *)map viewForAnnotation:(id <MKAnnotation>)annotation { MKPinAnnotationView *newAnnotation = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"greenPin"]; if ([annotation isKindOfClass:[ManageAnnotations class]]) { static NSString* identifier = @"ManageAnnotations"; MKPinAnnotationView *newAnnotation = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier]; if (newAnnotation==nil) { newAnnotation=[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier]; }else { newAnnotation.annotation=annotation; } newAnnotation.pinColor = MKPinAnnotationColorGreen; newAnnotation.animatesDrop = YES; newAnnotation.canShowCallout = YES; newAnnotation.rightCalloutAccessoryView=[UIButton buttonWithType:UIButtonTypeInfoLight]; return newAnnotation; }else { newAnnotation.pinColor = MKPinAnnotationColorGreen; newAnnotation.animatesDrop = YES; newAnnotation.canShowCallout = YES; return newAnnotation; } ManageAnnotations.m : @implementation ManageAnnotations @synthesize pinColor; @synthesize storeName=_storeName; @synthesize storeAdress=_storeAdress; @synthesize coordinate=_coordinate; -(id)initWithTitle:(NSString*)storeName adress:(NSString*)storeAdress coordinate:(CLLocationCoordinate2D)coordinate{ if((self=[super init])){ _storeName=[storeName copy]; _storeAdress=[storeAdress copy]; _coordinate=coordinate; } return self; } -(NSString*)title{ return _storeName; } -(NSString*)subtitle{ return _storeAdress; } ManageAnnotations.h @interface ManageAnnotations : NSObject<MKAnnotation>{ NSString *_storeName; NSString *_storeAdress; CLLocationCoordinate2D _coordinate; } // @property(nonatomic,assign)MKPinAnnotationColor pinColor; @property(nonatomic, readonly, copy)NSString *storeName; @property(nonatomic, readonly, copy)NSString *storeAdress; @property(nonatomic,readonly)CLLocationCoordinate2D coordinate; // -(id)initWithTitle:(NSString*)storeName adress:(NSString*)storeAdress coordinate:(CLLocationCoordinate2D)coordinate; // The PINS are shown correctly on the Map, but without the info button on the right of the view. Am i missing something?

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  • Java HashMap containsKey always false

    - by Dennis
    I have the funny situation, that I store a Coordinate into a HashMap<Coordinate, GUIGameField>. Now, the strange thing about it is, that I have a fragment of code, which should guard, that no coordinate should be used twice. But if I debug this code: if (mapForLevel.containsKey(coord)) { throw new IllegalStateException("This coordinate is already used!"); } else { ...do stuff... } ... the containsKey always returns false, although I stored a coordinate with a hashcode of 9731 into the map and the current coord also has the hashcode 9731. After that, the mapForLevel.entrySet() looks like: (java.util.HashMap$EntrySet) [(270,90)=gui.GUIGameField@29e357, (270,90)=gui.GUIGameField@ca470] What could I have possibly done wrong? I ran out of ideas. Thanks for any help! public class Coordinate { int xCoord; int yCoord; public Coordinate(int x, int y) { ...store params in attributes... } ...getters & setters... @Override public int hashCode() { int hash = 1; hash = hash * 41 + this.xCoord; hash = hash * 31 + this.yCoord; return hash; } }

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  • Get latlng and draw a polyline between that two latlng

    - by anup sharma
    I have some issue in my code in that first I want to get latlng of my given address/city name from two text boxes after that i converts it to from position's latlng and to position's latlng and at last i want to draw a polyline between these point and markers on both point also, But now i am trying to draw a line between these points. But still not working this code also no any error in console also. code is here for your help. function getRoute(){ var from_text = document.getElementById("travelFrom").value; var to_text = document.getElementById("travelTo").value; if(from_text == ""){ alert("Enter travel from field") document.getElementById("travelFrom").focus(); } else if(to_text == ""){ alert("Enter travel to field"); document.getElementById("travelTo").focus(); } else{ //google.maps.event.addListener(map, "", function (e) { var myLatLng = new google.maps.LatLng(28.6667, 77.2167); var mapOptions = { zoom: 3, center: myLatLng, mapTypeId: google.maps.MapTypeId.TERRAIN }; var map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions); var geocoder = new google.maps.Geocoder(); var address1 = from_text; var address2 = to_text; var from_latlng,to_latlng; //var prepath = path; //if(prepath){ // prepath.setMap(null); //} geocoder.geocode( { 'address': address1}, function(results, status) { if (status == google.maps.GeocoderStatus.OK) { // do something with the geocoded result // alert(results[0].geometry.location); from_latlng = results[0].geometry.location; // from_lat = results[0].geometry.location.latitude; // from_lng = results[0].geometry.location.longitude; // alert(from_latlng); } }); geocoder.geocode( { 'address': address2}, function(results, status) { if (status == google.maps.GeocoderStatus.OK) { // do something with the geocoded result to_latlng = results[0].geometry.location; // to_lat = results[0].geometry.location.latitude; // to_lng = results[0].geometry.location.longitude; // results[0].geometry.location.longitude // alert(to_latlng) } }); setTimeout(function(){ var flightPlanCoordinates = [ new google.maps.LatLng(from_latlng), new google.maps.LatLng(to_latlng) ]; //alert("123") var polyline; polyline = new google.maps.Polyline({ path: flightPlanCoordinates, strokeColor: "#FF0000", strokeOpacity: 1.0, strokeWeight: 2 }); polyline.setMap(map); // assign to global var path // path = polyline; },4000); // }); } }

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  • reload an iFrame with the scrollbar set to a specific coordinate.

    - by Luis Armando
    I was wondering how could I reload any website using javascript and set it in a way that when it reloads the scrollbar is looking scrolled down to a certain position. I'm unsure as to how to look for this in Google honestly so I haven't digged up much =/. I think it has to be somewhere in the instruction to reload it and so far I have: document.getElementById('life').contentWindow.scroll(0,0); //doesn't work document.getElementById('life').contentWindow.location.reload(); although the first one gets me: Permission denied to get property Window.scroll of http://www.google.com.

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  • Flex - How do I get the absolute X and Y coordinate including HTML offset?

    - by Mauricio
    Hey everyone, I am calling a JS function through the ExternalInterface using Flex which requires the absolute X and Y coordinates to create a pop-up menu. The Flex application is displayed on the center of an HTML page, therefore there is an HTML X and Y offset to consider. I have tried using the LocalToGlobal and ContentToGlobal functions, but these are just giving me the X and Y coordinates relative to the Flex application, it is not considering the HTML X and Y offset of having the Flex app in the center of the page or varying different screen resolutions. Is the best approach to retrieve the HTML X and Y offset using JavaScript? Is there a Flex function I can use that provides the absolute X and Y coordinates based on the HTML page? Thanks!

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  • How to zoom image on mouseover at some XY coordinate in JSF?

    - by Paul
    This is the code I use to display images. <t:dataList var="item" value="#{occasionBean.messageInfo}" layout="simple"> <h:commandLink action="#{occasionBean.selectedImage}" > <h:graphicImage styleClass="thumbnail" width="100" height="100" url="#{item.imageSnapUrl}" onclick="return setMsgId(this.id,#{item.img_id},'#{item.imageUrl}');" id="test" onmouseover="" onmouseout=""> </h:graphicImage> </h:commandLink> </t:dataList> Please give some solution.

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  • How to change the coordinate of a point that is inside a GraphicsPath?

    - by Ben
    Is there anyway to change the coordinates of some of the points within a GraphicsPath object while leaving the other points where they are? The GraphicsPath object that gets passed into my method will contain a mixture of polygons and lines. My method would want to look something like: void UpdateGraphicsPath(GraphicsPath gPath, RectangleF regionToBeChanged, PointF delta) { // Find the points in gPath that are inside regionToBeChanged // and move them by delta. // gPath.PathPoints[i].X += delta.X; // Compiles but doesn't work } GraphicsPath.PathPoints seems to be readonly, so does GraphicsPath.PathData.Points. So I am wondering if this is even possible. Perhaps generating a new GraphicsPath object with an updated set of points? How can I know if a point is part of a line or a polygon? If anyone has any suggestions then I would be grateful.

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  • How can I plot an iteration coordinate(x,y) data with only label in GNUplot?

    - by Mojiiz Alamode
    I have the set of data like this 0 268 195 1 353 199 2 318 209 3 268 232 4 370 238 5 326 253 6 246 265 7 372 284 8 313 290 9 258 297 0 268 196 1 353 199 2 318 209 3 268 233 4 370 238 5 325 253 6 246 265 7 372 284 8 313 290 9 258 297 I would like to use first column for label and second and third for (x,y) plot, however, I would like to plot only one time label without iteration. How should I do? Thank you for help.

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  • Expand / Collapse Swimlane (Domain Specific Language) C#

    - by Tejas
    I have multiple swimlanes on the surface, Is it possible to have expand / collapse functionality to these swimlanes?. My swimlanes are going to contain different shapes (Image Shapes), Geometry shape etc. I have tried the nesting of a geometry shpes but it only contains the geometry shapes not image shapes i.e. I have already created a Geometry shape with it's type as a RectangleD and by writing its partial class I have overridden the Expand() and Collapse() methods but to no avail because this particular Shape (Container) going to contain only Geometry shapes and not the Image shapes. Now I am trying to expand / collapse the swimlanes itself. Please let me know if anyone has done this before.

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  • Google maps spatial reference system

    - by JavaRocky
    What is Google map's spatial reference system using when you enter a lat, long into the maps search bar? I've found hints that it might be WGS84 but after converting to that coordinate system, nothing shows up when i paste the coordinates into the google maps search box. I am converting from GDA MGA 56. Sample: Input MGA56 coords: 336301, 6253363 Expected WGS86 coords: -33.8473340793201, 151.230631835944 I get: 16834916.928327594 -4008321.1020318186 Spatial coord systems: EPSG:28356 for MGA56 EPSG:900913 for WGS86 (google maps) I am using geotools to do the transform: CoordinateReferenceSystem crsMga56 = CRS.parseWKT(mga56); CoordinateReferenceSystem crsGmaps = CRS.parseWKT(gmaps); Coordinate coordinate = new Coordinate(336301, 6253363); Point point = new GeometryFactory().createPoint(coordinate); MathTransform transform = CRS.findMathTransform(crsMga56, crsGmaps); Geometry geometry = JTS.transform(point, transform); I know the transform is not correct, as when i use an online tool it gives me the correct coords. http://www.environment.gov.au/cgi-bin/transform/mga2geo%5Fgda.pl?east=336301&north=6253363&zone=56

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  • How to reproject a shapefile from WGS 84 to Spherical/Web Mercator projection.

    - by samkea
    Definitions: You will need to know the meaning of these terms below. I have given a small description to the acronyms but you can google and know more about them. #1:WGS-84- World Geodetic Systems (1984)- is a standard reference coordinate system used for Cartography, Geodesy and Navigation. #2: EPGS-European Petroleum Survey Group-was a scientific organization with ties to the European petroleum industry consisting of specialists working in applied geodesy, surveying, and cartography related to oil exploration. EPSG::4326 is a common coordinate reference system that refers to WGS84 as (latitude, longitude) pair coordinates in degrees with Greenwich as the central meridian. Any degree representation (e.g., decimal or DMSH: degrees minutes seconds hemisphere) may be used. Which degree representation is used must be declared for the user by the supplier of data. So, the Spherical/Web Mercator projection is referred to as EPGS::3785 which is renamed to EPSG:900913 by google for use in googlemaps. The associated CRS(Coordinate Reference System) for this is the "Popular Visualisation CRS / Mercator ". This is the kind of projection that is used by GoogleMaps, BingMaps,OSM,Virtual Earth, Deep Earth excetra...to show interactive maps over the web with thier nearly precise coordinates.  Reprojection: After reading alot about reprojecting my coordinates from the deepearth project on Codeplex, i still could not do it. After some help from a colleague, i got my ball rolling.This is how i did it. #1 You need to download and open your shapefile using Q-GIS; its the one with the biggest number of coordinate reference systems/ projections. #2 Use the plugins menu, and enable ftools and the WFS plugin. #3 Use the Vector menu--> Data Management Tools and choose define current projection. Enable, use predefined reference system and choose WGS 84 coodinate system. I am personally in zone 36, so i chose WGS84-UTM Zone 36N under ( Projected Coordinate Systems--> Universal Transverse Mercator) and click ok. #4 Now use the Vector menu--> Data Management Tools and choose export to new projection. The same dialog will pop-up. Now choose WGS 84 EPGS::4326 under Geodetic Coordinate Systems. My Input user Defined Spatial Reference System should looks like this: +proj=tmerc +lat_0=0 +lon_0=33 +k=0.9996 +x_0=500000 +y_0=200000 +ellps=WGS84 +datum=WGS84 +units=m +no_defs Your Output user Defined Spatial Reference System should look like this: +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs Browse for the place where the shapefile is going to be and give the shapefile a name(like origna_reprojected). If it prompts you to add the projected layer to the TOC, accept. There, you have your re-projected map with latitude and longitude pair of coordinates. #5 Now, this is not the actual Spherical/Web Mercator projection, but dont worry, this is where you have to stop. All the other custom web-mapping portals will pick this projection and transform it into EPGS::3785 or EPSG:900913 but the coordinates will still remain as the LatLon pair of the projected shapefile. If you want to test, a particular know point, Q-GIS has a lot of room for that. Go ahead and test it.

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  • Can get coordinates from iPhone simulator, but can't get coordinates from iPhone device

    - by iPhoneARguy
    Hi everyone, I've run into something of a mysterious bug (to me). I have some code to pick out the user's current location on the iPhone SDK. It works fine on the iPhone simulator, but when I try to run it on the actual device, I get a weird error. Here is the code (I am using ASIFormDataRequest to create a POST request): ASIFormDataRequest * request = [ASIFormDataRequest requestWithURL:url]; [request setPostValue:@"testauthor" forKey:@"author"]; [request setPostValue:[[NSNumber numberWithDouble:datum.location.coordinate.latitude] stringValue] forKey:@"latitude"]; NSLog(@"%f", datum.location.coordinate.latitude); NSLog(@"%f", datum.location.coordinate.longitude); [request setPostValue:[[NSNumber numberWithDouble:datum.location.coordinate.longitude] stringValue] forKey:@"longitude"]; [request setPostValue:datum.comment forKey:@"comment"]; On the simulator, NSLog does log both the latitude and longitude, but on the iPhone, it does not. Even stranger, when I go through with the debugger on the device, I try "po datum.location", I get <+###, -###> +/- 223.10m (speed 0.00 mps / course -1.00) @ 2010-05-02 22:18:37 -0400 (### replaced by my location) but when I do "(gdb) po datum.location.coordinate" I get: There is no member named coordinate. Do you guys have any idea why this might happen? Thanks in advance for your help!

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