TODO

Framework

Drop quads, add support for generalized indexed triangle strips/fans instead
Add materials support; store vertex buffers per-material, render correspondingly; use PolygonOffset for ordering; lines are `material' too
Add texture coordinate support (enhances materials)
Add shadows (stencil?) (requires materials and landuse polygons)
- To begin with, use preprojected polygonal shadows (needs polygon merger)
Tweak lines so they don't fill (ortho) map on low zoom levels
Completely switch to new-world OpenGL
- glBegin/end/color -> glUniform
- Fixed pipeline -> shaders
- gl*Pointer, glClient* -> glVertexAttribPointer
Support for billboards (for POIs)
Support for street names

Implement tagdict for efficient tag storage
Add support for tagged nodes
Add support for osm-diff loading (data may be added, changed and removed)
Add support for working in replication mode without having to hold planet (or some fixed region) in memory; database support is needed, maybe with external utilities

Add generic `polygon' primitive to represent general and multi-polygons
Support landuse=* and natural=* polygons (needs materials)
Add point feature support
- For starters, power=tower and amenity=bench
Fix road turns (curves instead of sharp spike)
Add proper support for street intersections
Render lanes
Multipolygon support
Basic CSG - don't draw edges on flat joined walls
Automatic edger - takes geometry, creates edges for it, automatically removes duplicate edges and edges for flat surfaces
Automatic merger for flat polygons (roads)
Straight skeleton implementation for arbitrary hipped roofs
Less restrictions on building shapes for other roof types (done for pyramidal/conical)

Some-tree indexing of points
Render lines as well
BBox support
Multiple LODs implemented in a same way as interlaced png's, e.g. each 8 (contig.) track points will be distributed into 4 levels as follows: L1 will 0th, L2 will hold 4th, L3 will hold 2nd, 6th and L3 will hold 1st, 3rd, 5th and 7th. By rendering L1, L1+L2, L1+L2+L3 or L1+L2+L3+L4 one can achieve desired point density.

Proper handling of absent SRTM files - don't just die
Add support in other layers
- Buildings should just be risen to appear on the ground
- Flat objects should be split, preferably into indexed strips as well
LODs should be implemented (as simple as 2^-n * x grid downscaling)

OsmDatasource should have iterator-based interface with postgres schema in mind (are things like way-by-node possible? - required for geomgen)
All external interfaces (especially Viewers) should have double "human unit" (lot/lan/height/angle) interface, not obscure internal fixed points
Split geomgen into topic files (Roofs, Walls, Roads etc.)

XML parsing takes most of time: finish libfastosm (my very fast XML parser specially for OSM) and use it
In geometry generation optimization focus should be optimal tags processing (std::string ops take quite a lot of time) and TranslatePoints optimization
Add pprof (google-perf-tools) profiling support to cmake

Render multiple tiles in one go (e.g. 16x16)
Optionally, symlink empty tiles
Use multiple threads for png saving
getopt_long interface
Ability to render single image of arbitrary size
Need 16x multisampling for proper eyecandy, while hardware only provides 4x. Can think of accum buffer (it's very slow, but rendering likely won't be a bottleneck anyway) or render to texture with following downscaling
Add jpeg saving support (more useful than png when texture support is added)
Support rendering over existing tiles (allows to add more regions to existing tileset)

Qt viewer
Mobile viewer (likely Qt as well)
Geometry generator (like tiler, but for geometry)
Persistent app for continuous database change watching and geometry tile updating - can be a base for other services (usable client, tile rendering infrastructure)