on January 25, 2023

OpenLayers only keeps the first drawn feature

Geographic Information Systems

How do you draw lines in OpenLayers?

Select a geometry type from the dropdown above to start drawing. To finish drawing, click the last point. To activate freehand drawing for lines, polygons, and circles, hold the Shift key. To remove the last point of a line or polygon, press “Undo”.

How do OpenLayers work?

OpenLayers allows you to build entire mapping applications from the ground up, with the ability to customize every aspect of your map—layers, controls, events, etc. You can use a multitude of different map server backends together, including a powerful vector layer. It makes creating map ‘mashups’ extremely easy.

How do you create a simple map with a marker in OpenLayers?

How to create a simple map (with a marker) using OpenLayers ?

  1. Put a element where you want your map to be.
  2. Now you can add a
  1. Step 1: Enter edit mode by.
  2. Step 2: Select on the right side Draw a line.
  3. Step 3: Move the cursor to the first point and click. Continue for subsequents vertices of the line.
  4. Step 4: Click once more on the last vertex to indicate that the line is ready.

 

How do I draw a line in OpenGL?

I want to draw a line in OpenGL. glBegin(GL_LINES); glVertex2f(.



With OpenGL2 :

  1. Divide x through by the window width, w , to get the point in the range from 0 to 1.
  2. Multiply it by 2 to get the range from 0 to 2.
  3. Subtract 1 to get the desired -1 to 1 range.
  4. Repeat for y value and windows height , h .