kuya

you're probably already aware of this, but there is some US legislation trying to open up commercial data to gov't entities:

https://www.congress.gov/bill/114th-congress/house-bill/1561...

there's some stuff being written this year as well for the side that i work (space). with all the upcoming sensor gaps, they're looking at alternative ways to cover.

for anyone interested, this paper has a nice background on numerical weather prediction

http://www.elsevierscitech.com/emails/physics/climate/the_or...

ah, thanks, that's fascinating.

"It also learns every time you actively report to the community on sky conditions and hazards, translating this information into weather predictions."

does sunshine actively run a numerical weather prediction model like WRF?

it'd be great to assimilate all these extra sensors into the NWP centre's models, but i imagine things like cal/val and WMO agreements to share data might make things difficult for commercial companies?

just curious, do you have references to smartphone sensors being utilized in numerical weather prediction?

i'd been browsing through some WMO reports and other associated NWP lit recently and i'd seen stuff on GPS-RO, but nothing on anyone assimilating "smart" devices.

if you check out the CGAL library, they have code that solves surface parameterization problems. the least squares conformal mapping is pretty nice for creating uv maps.

http://doc.cgal.org/latest/Surface_mesh_parameterization/gro...

http://doc.cgal.org/latest/Surface_mesh_parameterization/Sur...

not so coincidentally, human conversation protocols (at a high level) look a lot like some communication protocols:

https://en.wikipedia.org/wiki/Carrier_sense_multiple_access_...

Stupid phone: secular-specular

Ray tracing is a more generic term that covers rendering techniques which trace rays between a camera and a scene. Back in the day everyone used Whitted style ray tracers to render shiny metal blobs because secular reflections are trivially handled with ray tracing. Unfortunately other physical aspects of light like diffuse reflections were not handled by early ray tracing algorithms.

Kajiya introduced the rendering equation, a mathematical formulation of global illumination (takes diffuse, secular into account). It's a multidimensional integral equation. Unidirectional path tracing is an algorithm he introduced to solve the rendering equation. It uses several rays traced from pixels in the camera bouncing randomly through the scene. It's a Monte Carlo integration algorithm for solving the nasty integrals.

Photon mapping involves a pass algorithm tracing light from light sources into the scene, then a pass (like path tracing) gathering that light back at the camera. It better handles more complex light effects like caustics.

i built an interactive virtual globe using open gl (like nasa worldwind/google earth, but with real time satellite imagery). it's super fun.

when you're dealing with things like constellations of satellites, it's often useful to have a map alternative, since you can only (continuously) see half the earth at once with a globe.

conformality and area are preserved on globes, both physical and virtual (like in google earth). as a kid, i remember thinking africa was huge from the globes that teachers had in classrooms.

in ~2007 or so, i actually tried to buy a physical globe for my desk. i went into a couple office supply stores and the high school age employees had never even heard of a globe. it was the strangest thing trying to explain what a globe was: "it's like a ball with a map on it".