zIndex helps in managing the stack order of layers. When you add multiple layers in OpenLayers web application, all layers are stored as stack data structure. The layer which is added first, will be at the bottom of stack and layer which is added recently or last, will be on top of stack as shown …
An event is some thing a browser does or a user does. An event can be a mouse click on button or a right click, double click etc. Map Events in OpenLayers are specific to map. These events can help the developers to achieve a particular task. For example, opening a feature information popup of …
Hello Everyone, Welcome to next tutorial of open layers in which we will learn to create feature information tool on map click in OpenLayers. So what is Feature Information in GIS ? Feature information is Non-GIS information associated with GIS data. For complete source code of this tutorial, click here Check the Live Feature Information …
Create Feature Information Popup tool in OpenLayers on map click Read More »
In this tutorial, we are going to create a dynamic measurement tool in OpenLayers version 6.5. We will create a Line and Area measurement tool to show measurements on labels that follow changing geometry like area, length or cursor position as shown in the above GIF image Download the complete code of Dynamic Measurement from …
OpenLayers is a great open source GIS library which is used to develop a rich featured GIS web applications. But sometime you need to implement advanced spatial/geometrical operations. For example, union of two geometry, creating buffers, creating hole in polygon, dividing a polygon in two parts by a line as shown in following images. But, …
Perform complex spatial operations in OpenLayers using JSTS Read More »
For Part-1, Click here ol.View, ol.layer and ol.source are one of the foundations of OpenLayers application. You can not move ahead without understanding them. Let’s understand them with the help of following code. ol.View: It is used to set the view of map. At line number 25 in above code snippet, our map object(defined at …
In this post, we will merge two polygons in OpenLayers(polygons that intersect each other) into one polygon as shown in the above GIF image. The merging of two polygons is also known as the union of two polygons. In the last tutorial, we demonstrated how we can split a polygon by a line into two …
Projections or Map Projections are attempts to portray the 3D surface of the earth or a portion of the earth on flat surface like flat surface or XY plane or Cartesian Plane. The method by which 3D earth surface or curved surface is laid flat to a flat surface or XY plane is known as …
What is GIS ? GIS stands for Geographical Information System(GIS). It is a system for gathering, storing and analysing GIS data. A GIS data is a data which has some location information associated with it. A very simple and popular example is GPS on your smart phone. Through GPS and Satellite, we gather our live location …
Prerequisite: You need to have beginner level knowledge of QGIS and PostGIS to understand this post. QGIS and PostGIS are one of the most famous open source GIS tools in GIS community. QGIS is used for the visualisation and processing of GIS data where as PostGIS is an extension to PostgreSQL database to store GIS …
