Follow the approach from mapbox-gl-js for enabling opaque pass for background layer (same as for fill layer).
Fix combinations/heatmap-translucent--background-opaque render test.
This fixes following issues:
* Fix some false passing combinations/fill-extrusion-translucent--XXXX tests
* Fix and enable other, failing but ignored, combinations/fill-extrusion-translucent--XXXX tests
* Fix rendering of layers that are on top of fill-extrusion layers
state.getProjMatrix(nearClippedProjMatrix, 100) caused that tests with size 64x64 were not
rendering fill extrusions: far plane calculated as 96.9 and near plane set to 100 was the cause.
near plane is changed from hardcoded 100 to depend on state.getCameraToCenterDistance() - producing
similar value but one that follows max zoom.
This caused that e.g. combinations/fill-extrusion-translucent--fill-opaque was falsely passing as
only fill-opaque layer got rendered.
combinations/fill-extrusion-translucent--XXXX tests expose regression https://github.com/mapbox/mapbox-gl-native/issues/14844#issuecomment-503600034 in #14844, #14779.
Fix (opaquePassCutoff, is3D) is ported from https://github.com/mapbox/mapbox-gl-js/pull/7821Fixes: #14844, #14779, #15039
In order to test the conversion from function to expressions using the
legacy tests in the expression test suite, parse function objects into
expressions in NodeExpression::Parse.
v2: Coding style fixes.
Refactor out HeadlessFrontend and HeadlessBackend gl independent code to gfx.
Define gl::HeadlessBackend as subclass, instantiated by gfx::HeadlessBackend static factory method.
GL dependent tests are still using gl::HeadlessBackend directly (not through gfx).
- Do not carry it over everywhere as parameter, it is a shared
instance anyway and the lifecycle is pretty much the app lifecycle
from the moment we instantiate a map.
- Rename to BackgroundScheduler because it is a Scheduler that will
do tasks in the background, we don't make assumptions if it is a
thread pool or a single thread.
- Most importantly, remove the dependency from `core` on `platform`.
Using different exception pointers to specify the loading failure makes
an awkward API. Most users rethrow the exception only to figure out what
type of error happened so it can be reported properly. So replace the
exception pointer with a enum an string description of the failure.
Instead of having individual APIs for setting axonometric
and skew options, create ProjectionMode struct that holds
all the relevant options for Axonometric rendering and
introduce setter/getter on the Map for those options.
