Velocity

Example

#include <fstream>

#include "nlohmann/json.hpp"

#include "xleaflet/xmap.hpp"
#include "xleaflet/xvelocity.hpp"

auto map = xlf::map::initialize()
    .center({0, 0})
    .zoom(1)
    .finalize();

auto base_layer = xlf::basemap({"CartoDB", "DarkMatter"});
map.add_layer(base_layer);

std::ifstream file("velocity_data.json");
nlohmann::json data;
file >> data;

auto velocity = xlf::velocity::initialize()
    .data(data)
    .velocity_scale(0.01)
    .max_velocity(20)
    .display_options(R"({
        "velocityType": "Global Wind",
        "displayPosition": "bottomleft",
        "displayEmptyString": "No wind data"
    })")
    .finalize();

map.add_layer(velocity);

map

Attributes

Attribute	Default Value	Doc
data	Null JSON objectdataset	Underlying dataset
units	None	Units
display_values	True	Display velocity data on mouse hover
display_options	{}	Display options
min_velocity	0.0	Used to align color scale
max_velocity	10.0	Used to align color scale
velocity_scale	0.005	Modifier for particle animations
color_scale	Empty std::vector of html colors	Array of hex/rgb colors for user-specified color scale.