Add 3-d option for choropleth extrusion; support pitch and bearing arguments for MapViz

[akacarlyann]

Addresses #4, #15; closes #83

[ryanbaumann]

Hehe, this is awesome @akacarlyann. Nice work!

Notes:

• Tooltips: if the same measure is used for both height and color, do not put the same property in the tooltip twice.
• Legend: if a different measure is used for color and height, we should mention the measure in the legend and indicate what color vs. height represents.

Unrelated note on performance:

• We're tracking a data-join performance regression here in GL JS Data-Join method performance regression between 0.42.0 and 0.44.1 mapbox-gl-js#6367. Once it's addressed in a future GL JS release, the data-join technique should work well even for 100k unique features to join in the browser.

[ryanbaumann]

@akacarlyann no rush here yet, but wondering if you've had a chance for to take a pass on any of the feedback above or are ready for a final PR review.

[akacarlyann]

@ryanbaumann funny timing - I'm heading to the coffee shop to work on this today! It's my first chance in a couple weeks. For the SF population graphic, there is an updating scale 3d height in the legend. Is there any public source code you can think of that might implement something similar? Otherwise I'll just handle it similarly to the way we do color v radius for the graduated circle viz.

[ryanbaumann]

@akacarlyann the legend in www.mapbox.com/bites/00273 is pretty custom CSS and HTML - I'd have to search around to see if there are any modularized components for size extruded / 3D data visualizations

[akacarlyann]

@ryanbaumann Got it. Removed duplicate add to tooltip if height_property equals color_property and added note to legend title if height based on different property from color. Ready for you to take a look.

[ryanbaumann]

Nice work @akacarlyann. A few updates to tests for coverage of the new utils function height_map and I think we're ready to merge.

[lucasvw]

Hi guys, really cool feature! One thing though, you currently dont check the height_default parameter to set self.extrude to true.

[ryanbaumann]

Thanks @lucasvw - could you open a quick issue ticket or PR for the change or bug? This PR is old. Thank you!