Detecting priority areas for mapping turn lanes

[planemad]

From #144 we need a smart way to focus turn lane mapping at decision points on the road where it is most important:

• High traffic roads
• High speed roads
• Complex intersections
• Roads with high number of lanes

@pratikyadav as a first step can you write a simple overpass query and make a map of important junctions in the Bay Area that we can use? Tags to lookout for include highway=motorway_junction highway=traffic_signals highway=motorway highway=trunk

cc @lxbarth @ramyaragupathy

[pratikyadav]

Made a quick map to show major intersections in SF bay area.

The map shows following intersections -

• Black is Motorway vs Primary
• Red is Trunk vs Primary
• Blue is Motorway vs Trunk
• Green is Motorway_link vs Trunk
• Orange is Motorway_link vs Primary
• Black line color for highway=motorway

[planemad]

@pratikyadav this is looking good already. Minor additions:

• Intersections between motorway_link, trunk_link, primary_link
• motorway and motorway_link vs secondary, tertiary, unclassified
• highway=motorway_junction
• Simplify the style: Use color only to differentiate intersections vs highway=motorway_junction. Use size to represent importance of road.

[pratikyadav]

@planemad

Taking motorway as the top priority, here is the division of intersections-

Priority 1 [Motorway] vs [trunk and primary] size 12x12 pixel

with trunk

• motorway vs trunk
• motorway_link vs trunk_link
• motorway vs trunk_link
• motorway_link vs trunk

with primary

• motorway vs primary
• motorway_link vs primary_link
• motorway vs primary_link
• motorway_link vs primary

also highway=motorway_junctions as Red dots

Priority 2 [Motorway] vs [Secondary, tertiary and unclassified] size 8x8 pixel

• motorway vs secondary
• motorway_link vs secondary
• motorway vs tertiary
• motorway_link vs tertiary
• motorway vs unclassified
• motorway_link vs unclassifed

Priority 3 [Trunk] vs [Primary] size 4x4 pixel

• trunk vs primary
• trunk_link vs primary_link
• trunk_link vs primary
• trunk vs primary_link

Priority 4 [All others] not displayed in maps

Here is the map-> https://api.mapbox.com/v4/pratikyadav.0b8d1ee3/page.html?access_token=pk.eyJ1IjoicHJhdGlreWFkYXYiLCJhIjoiMTA2YWUxNjRkNmFmZGQ4YzAxZWFiNDk0NDM1YjE1YjAifQ.4P6N5dNmA_WQXd3BsJvu5w#11/37.4250/-121.9558

The transprent version of this layer can be used in JOSM using this tms layer-> tms[99]:https://api.mapbox.com/v4/pratikyadav.9cfd807b/{zoom}/{x}/{y}.png?access_token=pk.eyJ1IjoicHJhdGlreWFkYXYiLCJhIjoiMTA2YWUxNjRkNmFmZGQ4YzAxZWFiNDk0NDM1YjE1YjAifQ.4P6N5dNmA_WQXd3BsJvu5w

Black line are already mapped turn lanes

The overpass query used to extract these intersections is

[bbox:{{bbox}}];
way[highway=motorway];node(w)->.n1;
way[highway=trunk];node(w)->.n2;
node.n1.n2;

out meta;

How to knock these out?

Privious TM task boundary made it a little bit difficult to spot the exact places for mapping turn lanes. The next task can be made using buffer of 250m around the intersection points.

cc @lxbarth

[planemad]

@pratikyadav amazing! A 50m buffer around the points should be enough, can you share what such a buffer looks like?

We can do a trial run for the existing task with this overlay as a reference to see if this works better.

[pratikyadav]

Task based on highway=motorway_junctions for SF bay area @planemad

[planemad]

@pratikyadav looks great for now.

The important intersection missing in priority 3 is trunkvstrunk and primaryvs`primary. Can you check on IRC on how to extract that using overpass.

[pratikyadav]

@planemad had a talk about this on IRC. Looks like it is not possible using overpassturbo.
We might need some other tools to get trunk vs trunk(or motorway vs motorway) intersections.

[planemad]

Lets line up a task with this that we can jump on once SF buildings are done:

• @pratikyadav draft a project with instructions on US TM

[pratikyadav]

#153
Moved here^