On Demand or On fly tiles Render

Hey All. Today I want to discuss the concept of tiles rendering.

There are two types of rendering the tiles.

  1. Rendering on demand- The tiles are render when you zoom or go to that location.
  2. Rendering on the fly- Pre-render the tiles without zooming it again and again.

The command to render the list of map tiles by sending the request to rendering daemon. It will pre-render the tiles.

$ render_list -m default -a -z 0 -Z 10

Output

debug: init_storage_backend: initialising file storage backend at: /var/lib/mod_tile
Rendering client
Starting 1 rendering threads
Rendering all tiles from zoom 0 to zoom 10
Rendering all tiles for zoom 0 from (0, 0) to (0, 0)
Rendering all tiles for zoom 1 from (0, 0) to (1, 1)
Rendering all tiles for zoom 2 from (0, 0) to (3, 3)
Rendering all tiles for zoom 3 from (0, 0) to (7, 7)
Rendering all tiles for zoom 4 from (0, 0) to (15, 15)
Rendering all tiles for zoom 5 from (0, 0) to (31, 31)
Rendering all tiles for zoom 6 from (0, 0) to (63, 63)
Rendering all tiles for zoom 7 from (0, 0) to (127, 127)
Rendering all tiles for zoom 8 from (0, 0) to (255, 255)

Here, the flag -m means long prompt. This command takes some time. While the command was executing, I got to know the maths behind the tiles at a particular level.

Assume zoom level is x then the tiles are render from (0,0) to
((2^x-1),(2^x-1))

Screenshot from 2017-06-19 20-36-47.png

This picture clearly shows what above explained.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s