[core] Use gl::Program to resolve some rough edges in the GL binding types

* Extract `ignore` util to separate header.
* `Segment` now tracks offset and length of indices, rather than primitives. This is more natural.
* Introduce `VertexVector` and `IndexVector` types. These types carry information about the intended draw mode (`Triangles`, `LineStrip`, etc.), and ensure that elements are always appended in a group size appropriate for that draw mode, for both indexed and unindexed rendering.
* `Program`, rather than `Drawable`, is now the unifying object for draw calls. `Program` is the best place to type check the draw call, because it is typed to carry information about the intended primitive, vertex type, attributes, and uniforms.
* Use the debug shaders for debug tile rendering, like gl-js.
* Fix the draw mode for background. It was drawing triangle strips with a triangles array. Surprised this didn’t cause issues. Now it’s type checked.

1 files changed, 5 insertions, 5 deletions

diff --git a/src/mbgl/renderer/fill_bucket.hpp b/src/mbgl/renderer/fill_bucket.hpp
index b2c549a758..4ea558b629 100644
--- a/src/mbgl/renderer/fill_bucket.hpp
+++ b/src/mbgl/renderer/fill_bucket.hpp
@@ -19,15 +19,15 @@ public:
 
     void addGeometry(const GeometryCollection&);
 
-    std::vector<FillVertex> vertices;
-    std::vector<gl::Line> lines;
-    std::vector<gl::Triangle> triangles;
+    gl::VertexVector<FillVertex> vertices;
+    gl::IndexVector<gl::Lines> lines;
+    gl::IndexVector<gl::Triangles> triangles;
     std::vector<gl::Segment> lineSegments;
     std::vector<gl::Segment> triangleSegments;
 
     optional<gl::VertexBuffer<FillVertex>> vertexBuffer;
-    optional<gl::IndexBuffer<gl::Line>> lineIndexBuffer;
-    optional<gl::IndexBuffer<gl::Triangle>> triangleIndexBuffer;
+    optional<gl::IndexBuffer<gl::Lines>> lineIndexBuffer;
+    optional<gl::IndexBuffer<gl::Triangles>> triangleIndexBuffer;
 };
 
 } // namespace mbgl