Creating Routes
Unigine has a built-in pathfinding system that includes navigation areas, obstacles and functions of the PathRoute class that are used to calculate the optimal routes among obstacles within navigation areas.
Via UnigineEditor, you can only add a navigation area (a sector or a mesh) to the scene and place obstacles. The 2D or 3D route that is calculated within the navigation area should be created from the code.
Creating a Route within Navigation Area#
To create a route within a navigation area, in which no obstacles are placed, you can use the following:
// create a new route
PathRoutePtr route = PathRoute::create();
// set a radius for the point which will move along the route
route->setRadius(2.0f);
// declare points between which the route should be calculated
Vec3 p0 = Vec3(-60.0f,-60.0f,5.0f);
Vec3 p1 = Vec3( 60.0f, 60.0f,5.0f);
// create a 3D route
route->create3D(p0,p1);
To visualize the calculated route, call the renderVisualizer() function of the PathRoute class:
route->renderVisualizer(vec4(1.0f));
sector->renderVisualizer();
You can affect route calculation via UnigineEditor by adjusting parameters of the navigation sector or mesh.
Creating a Route within Navigation Area with Obstacles#
Creating the route within a navigation area with obstacles is similar to creating the route within an empty navigation area. Moreover, the route will be recalculated if the obstacle changes its transformation.
If the obstacle is connected with a dynamically changing node that should be bypassed, this node should be set as a parent node for the obstacle. This will enable simultaneous changing transformation of the node and the obstacle. For example:
// AppWorldLogic.h
#include <UnigineLogic.h>
#include <UnigineStreams.h>
#include <UnigineObjects.h>
#include <UniginePathFinding.h>
class AppWorldLogic : public Unigine::WorldLogic {
public:
AppWorldLogic();
virtual ~AppWorldLogic();
virtual int init();
virtual int update();
virtual int postUpdate();
virtual int updatePhysics();
virtual int shutdown();
virtual int save(const Unigine::StreamPtr &stream);
virtual int restore(const Unigine::StreamPtr &stream);
private:
// declare the required variables
Unigine::ObstacleBoxPtr box;
Unigine::ObjectMeshStaticPtr mesh;
Unigine::PathRoutePtr route;
// declare points between which a route should be calculated
Unigine::Math::Vec3 p0 = Unigine::Math::Vec3(-60.0f, -60.0f, 5.0f);
Unigine::Math::Vec3 p1 = Unigine::Math::Vec3(60.0f, 60.0f, 5.0f);
};
// AppWorldLogic.cpp
#include <UnigineEditor.h>
#include <UnigineGame.h>
#include <UnigineVisualizer.h>
#include <UnigineLog.h>
using namespace Unigine;
using namespace Math;
int AppWorldLogic::init() {
// enable the engine visualizer
Visualizer::setEnabled(1);
// create a navigation sector within which pathfinding will be performed
NavigationSectorPtr navigation = NavigationSector::create(vec3(128.0f, 128.0f, 8.0f));
navigation->setWorldTransform(translate(Vec3(1.0f, 1.0f, 5.0f)));
// create a mesh by adding a box surface to it
MeshPtr mesh_0 = Mesh::create();
mesh_0->addBoxSurface("box_surface", vec3(1.0f));
// create the ObjectMeshStatic that should be bypassed
mesh = ObjectMeshStatic::create(mesh_0);
mesh->setMaterial("mesh_base", "*");
mesh->setPosition(Vec3(2.0f, 2.2f, 1.5f));
mesh->setScale(vec3(2.0f, 2.0f, 2.0f));
// create an obstacle
box = ObstacleBox::create(vec3(1.2f, 1.2f, 1.2f));
box->setPosition(Vec3(0.0f, 0.0f, 0.0f));
// add the obstacle as the child node to the mesh in order to change their transformation simultaneously
mesh->addChild(box);
// create a new route
route = PathRoute::create();
// set a radius for the point which will move along the route
route->setRadius(1.2f);
return 1;
}
// start of the main loop
int AppWorldLogic::update() {
// get the frame duration
float ifps = Game::getIFps();
// and define the angle of the object's rotation
float angle = ifps * 90.0f;
// change transformation of the mesh
mesh->setTransform(mesh->getTransform() * Mat4(rotateZ(angle)));
// render the bounding box of the obstacle
box->renderVisualizer();
// recalculate the route in the current frame and render its visualizer
route->create2D(p0, p1);
if (route->isReached()) route->renderVisualizer(vec4(1.0f));
else Log::message("PathRoute failed");
return 1;
}
In the result, you will have a simple navigation sector, in which the dynamically changing obstacle box is placed.