⛰️ Rocky

Rocky is a C++ SDK for rendering maps and globes.

Rocky will render an accurate 3D or 2D map with real geospatial imagery and elevation data. It supports thousands of map projections and many popular geodata sources including GeoTIFF, TMS, OpenStreetMap, WMTS, WMS, and Azure Maps. Rocky's data model is inspired by the osgEarth SDK, a 3D GIS toolkit created in 2008 and still in wide use today.

This project is in its early stages so expect a lot of API and architectural changes before version 1.0.

• Getting started
  • Build the SDK
    • Dependencies
  • Run the Demo
• Development
  • Hello, world
    • main.cpp
    • CMakeLists.txt
  • Rocky and Qt
  • Rocky and VulkanSceneGraph
  • Working with Maps
  • Drawing Annotations

---

Getting started

Build the SDK

Rocky uses CMake, and we maintain the build on Windows and Linux. Rocky comes with a handy Windows batch file to automatically configure the project using vcpkg:

bootstrap-vcpkg.bat

That will download and build all the dependencies (takes a while) and generate your CMake project and Visual Studio solution file.

If you would rather not use vcpkg, you can build and install the dependencies yourself, or use your favorite package manager (like apt on Linux).

Dependencies

Thanks to these excellent open source projects!

• cpp-httplib
• entt
• GDAL (optional)
• glm
• ImGui (optional)
• nlohmann-json
• openssl (optional)
• proj
• spdlog
• sqlite3 (optional)
• vsgXchange (optional)
• VulkanSceneGraph
• weejobs (embedded)

Run the Demo

Rocky is pretty good at finding its data files, but you might need so up a couple environment variables to help:

set ROCKY_FILE_PATH=%rocky_install_dir%/share/rocky
set ROCKY_DEFAULT_FONT=C:/windows/fonts/arialbd.ttf
set PROJ_DATA=%proj_install_dir%/share/proj

If you built with vcpkg you will also need to add the dependencies folder to your path; this will normally be found in vcpkg_installed/x64-windows (or whatever platform you are using).

Now we're ready:

rocky_demo

There are some JSON map files in the data folder. Load one with the --map option:

rocky_demo --map data\openstreetmap.map.json

Development

Hello, world

The easiest way to write a turnkey Rocky app is to use the rocky::Application object. It will create a viewer, a default map, and a scene graph to store everything you want to visualize.

main.cpp

#include <rocky/vsg/Application.h>
#include <rocky/TMSImageLayer.h>

int main(int argc, char** argv)
{
    rocky::Application app(argc, argv);

    auto imagery = rocky::TMSImageLayer::create();
    imagery->uri = "https://readymap.org/readymap/tiles/1.0.0/7/";
    app.mapNode->map->add(imagery);

    return app.run();
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.10)
project(myApp VERSION 0.1.0 LANGUAGES CXX C)
find_package(rocky CONFIG REQUIRED)
add_executable(myApp main.cpp)
target_link_libraries(myApp PRIVATE rocky::rocky)
install(TARGETS myApp RUNTIME DESTINATION bin)

Rocky and Qt

You can embed Rocky in a Qt widget. See the rocky_demo_qt example for details.

Rocky and VulkanSceneGraph

If you're already using VSG in your application and want to add a MapNode to a view, do this:

// Your VSG viewer:
auto viewer = vsg::Viewer::create();

// Make a runtime context for the viewer:
auto context = rocky::VSGContextFactory::create(viewer);

// Make a map node to render your map data:
auto mapNode = rocky::MapNode::create(context);

// optional - add one or more maps to your map:
auto layer = rocky::TMSImageLayer::create();
layer->uri = "https://[abc].tile.openstreetmap.org/{z}/{x}/{y}.png";
layer->setProfile(rocky::Profile::SPHERICAL_MERCATOR);
layer->setAttribution(rocky::Hyperlink{ "\u00a9 OpenStreetMap contributors", "https://openstreetmap.org/copyright" });
mapNode->map->add(layer);
...
scene->addChild(mapNode);
...
// Run your main loop as usual
while (viewer->advanceToNextFrame())
{        
    viewer->handleEvents();
    viewer->update();
    viewer->recordAndSubmit();
    viewer->present();
}

You'll probably also want to add the MapManipulator to that view to control the map:

viewer->addEventHandler(rocky::MapManipulator::create(mapNode, window, camera, context));

Working with Maps

Coming soon.

Drawing Annotations

Rocky has a set of building blocks for creating map annotations like labels, icons, and geometry. Rocky uses an ECS (entity component system) based on EnTT to store these primitives. Coming soon.

---