* Always return image metrics exclusive of padding
* Work with integer coordinates whenever possible
* Eliminate redundant SpriteAtlasElement members
* Fix asymmetric re-padding in getIconQuad when pixelRatio != 1
* Add explanatory comments
ported from -js: ef5582dd3bc5c15a3112e875ed66494dab8e9d0b
Project the extrusion and compare it's projected pixel length with the
actual pixel length and adjust antialiasing accordingly.
The previous approach calculated the adjustment much more indirectly and
had no intuitive explanation.
ported from -js: eb6c6596c6a7a61363d30356674e0002153b1d19
`altitude` was a terribly-named variable that was used to indirectly
control the fov. This should eliminate some confusion.
`altitude` was equivalent to `cameraToCenterDistance / height`
This converts the style property classes (CirclePaintProperties and so on) to the same tuple-based approach as gl::Attribute and gl::Uniform. The approach is outlined in https://github.com/mapbox/cpp/blob/master/C%2B%2B%20Structural%20Metaprogramming.md.
The main advantage of this approach is it allows writing algorithms that work on sets of style properties, without resorting to code generation or manually repetitive code. This lets us iterate on approaches to data-driven properties more easily.
Another advantage is that the cascading, unevaluated, and evaluated states of a set of properties exist as independent structures, instead of individual properties holding their own state. This is a more functional approach that makes data flow clearer and reduces state.
* [core] update shaders for line property functions
update deps, define device pixel ratio for all shaders
[core] create ShaderParameter struct to store pixel ratio and overdraw param
repair rebase errs
update shaders to include pixel ratio
make sure collision_box never overdraws
update test suite, move shaders to Painter::render so the correct pixel ratio is applied
move shader compiling back to the Painter constructor
rebase from shader --> program refactor
re-factor parameters for collisionBox and debug programs
remove unused vars from line-program, move blur math to shader
update core files
remove unecessary files
update shaders PR, remove comments
bump test suite sha
fix formatting, incorporate feedback
refactor program.hpp
* [core] remove line transformations that were moved to the shaders, bump shader sha
* [core] shorten ProgramParameter instantiation
* [core] bump shader+test suite shas
