e6be3f68da
- Added Navigation Agents and Obstacles. - Integrated Collision Avoidance. This work has been kindly sponsored by IMVU.
407 lines
15 KiB
C++
407 lines
15 KiB
C++
/*
|
|
* RVO.h
|
|
* RVO2-3D Library
|
|
*
|
|
* Copyright 2008 University of North Carolina at Chapel Hill
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
* Please send all bug reports to <geom@cs.unc.edu>.
|
|
*
|
|
* The authors may be contacted via:
|
|
*
|
|
* Jur van den Berg, Stephen J. Guy, Jamie Snape, Ming C. Lin, Dinesh Manocha
|
|
* Dept. of Computer Science
|
|
* 201 S. Columbia St.
|
|
* Frederick P. Brooks, Jr. Computer Science Bldg.
|
|
* Chapel Hill, N.C. 27599-3175
|
|
* United States of America
|
|
*
|
|
* <http://gamma.cs.unc.edu/RVO2/>
|
|
*/
|
|
|
|
#ifndef RVO_RVO_H_
|
|
#define RVO_RVO_H_
|
|
|
|
#include "API.h"
|
|
#include "RVOSimulator.h"
|
|
#include "Vector3.h"
|
|
|
|
/**
|
|
|
|
\file RVO.h
|
|
\brief Includes all public headers in the library.
|
|
|
|
\namespace RVO
|
|
\brief Contains all classes, functions, and constants used in the library.
|
|
|
|
\mainpage RVO2-3D Library
|
|
|
|
\author Jur van den Berg, Stephen J. Guy, Jamie Snape, Ming C. Lin, and Dinesh Manocha
|
|
|
|
<b>RVO2-3D Library</b> is an easy-to-use C++ implementation of the
|
|
<a href="http://gamma.cs.unc.edu/CA/">Optimal Reciprocal Collision Avoidance</a>
|
|
(ORCA) formulation for multi-agent simulation in three dimensions. <b>RVO2-3D Library</b>
|
|
automatically uses parallelism for computing the motion of the agents if your machine
|
|
has multiple processors and your compiler supports <a href="http://www.openmp.org/">
|
|
OpenMP</a>.
|
|
|
|
Please follow the following steps to install and use <b>RVO2-3D Library</b>.
|
|
|
|
- \subpage whatsnew
|
|
- \subpage building
|
|
- \subpage using
|
|
- \subpage params
|
|
|
|
See the documentation of the RVO::RVOSimulator class for an exhaustive list of
|
|
public functions of <b>RVO2-3D Library</b>.
|
|
|
|
<b>RVO2-3D Library</b>, accompanying example code, and this documentation is
|
|
released for educational, research, and non-profit purposes under the following
|
|
\subpage terms "terms and conditions".
|
|
|
|
|
|
\page whatsnew What Is New in RVO2-3D Library
|
|
|
|
\section localca Three Dimensions
|
|
|
|
In contrast to RVO2 Library, <b>RVO2-3D Library</b> operates in 3D workspaces. It uses
|
|
a three dimensional implementation of <a href="http://gamma.cs.unc.edu/CA/">Optimal
|
|
Reciprocal Collision Avoidance</a> (ORCA) for local collision avoidance. <b>RVO2-3D
|
|
Library</b> does not replace RVO2 Library; for 2D applications, RVO2 Library should
|
|
be used.
|
|
|
|
\section structure Structure of RVO2-3D Library
|
|
|
|
The structure of <b>RVO2-3D Library</b> is similar to that of RVO2 Library.
|
|
Users familiar with RVO2 Library should find little trouble in using <b>RVO2-3D
|
|
Library</b>. <b>RVO2-3D Library</b> currently does not support static obstacles.
|
|
|
|
\page building Building RVO2-3D Library
|
|
|
|
We assume that you have downloaded <b>RVO2-3D Library</b> and unpacked the ZIP
|
|
archive to a path <tt>$RVO_ROOT</tt>.
|
|
|
|
\section xcode Apple Xcode 4.x
|
|
|
|
Open <tt>$RVO_ROOT/RVO.xcodeproj</tt> and select the <tt>Static Library</tt> scheme. A static library <tt>libRVO.a</tt> will be built in the default build directory.
|
|
|
|
\section cmake CMake
|
|
|
|
Create and switch to your chosen build directory, e.g. <tt>$RVO_ROOT/build</tt>.
|
|
Run <tt>cmake</tt> inside the build directory on the source directory, e.g.
|
|
<tt>cmake $RVO_ROOT/src</tt>. Build files for the default generator for your
|
|
platform will be generated in the build directory.
|
|
|
|
\section make GNU Make
|
|
|
|
Switch to the source directory <tt>$RVO_ROOT/src</tt> and run <tt>make</tt>.
|
|
Public header files (<tt>API.h</tt>, <tt>RVO.h</tt>, <tt>RVOSimulator.h</tt>, and <tt>Vector3.h</tt>) will be copied to the <tt>$RVO_ROOT/include</tt> directory and a static library <tt>libRVO.a</tt> will be compiled into the
|
|
<tt>$RVO_ROOT/lib</tt> directory.
|
|
|
|
\section visual Microsoft Visual Studio 2010
|
|
|
|
Open <tt>$RVO_ROOT/RVO.sln</tt> and select the <tt>RVOStatic</tt> project and a
|
|
configuration (<tt>Debug</tt> or <tt>Release</tt>). Public header files (<tt>API.h</tt>, <tt>RVO.h</tt>, <tt>RVOSimulator.h</tt>, and <tt>Vector3.h</tt>) will be copied to the <tt>$RVO_ROOT/include</tt> directory and a static library, e.g. <tt>RVO.lib</tt>, will be compiled into the
|
|
<tt>$RVO_ROOT/lib</tt> directory.
|
|
|
|
|
|
\page using Using RVO2-3D Library
|
|
|
|
\section structure Structure
|
|
|
|
A program performing an <b>RVO2-3D Library</b> simulation has the following global
|
|
structure.
|
|
|
|
\code
|
|
#include <RVO.h>
|
|
|
|
std::vector<RVO::Vector3> goals;
|
|
|
|
int main()
|
|
{
|
|
// Create a new simulator instance.
|
|
RVO::RVOSimulator* sim = new RVO::RVOSimulator();
|
|
|
|
// Set up the scenario.
|
|
setupScenario(sim);
|
|
|
|
// Perform (and manipulate) the simulation.
|
|
do {
|
|
updateVisualization(sim);
|
|
setPreferredVelocities(sim);
|
|
sim->doStep();
|
|
} while (!reachedGoal(sim));
|
|
|
|
delete sim;
|
|
}
|
|
\endcode
|
|
|
|
In order to use <b>RVO2-3D Library</b>, the user needs to include RVO.h. The first
|
|
step is then to create an instance of RVO::RVOSimulator. Then, the process
|
|
consists of two stages. The first stage is specifying the simulation scenario
|
|
and its parameters. In the above example program, this is done in the method
|
|
setupScenario(...), which we will discuss below. The second stage is the actual
|
|
performing of the simulation.
|
|
|
|
In the above example program, simulation steps are taken until all
|
|
the agents have reached some predefined goals. Prior to each simulation step,
|
|
we set the preferred velocity for each agent, i.e. the
|
|
velocity the agent would have taken if there were no other agents around, in the
|
|
method setPreferredVelocities(...). The simulator computes the actual velocities
|
|
of the agents and attempts to follow the preferred velocities as closely as
|
|
possible while guaranteeing collision avoidance at the same time. During the
|
|
simulation, the user may want to retrieve information from the simulation for
|
|
instance to visualize the simulation. In the above example program, this is done
|
|
in the method updateVisualization(...), which we will discuss below. It is also
|
|
possible to manipulate the simulation during the simulation, for instance by
|
|
changing positions, radii, velocities, etc. of the agents.
|
|
|
|
\section spec Setting up the Simulation Scenario
|
|
|
|
A scenario that is to be simulated can be set up as follows. A scenario consists
|
|
of a set of agents that can be manually specified. Agents may be added anytime
|
|
before or during the simulation. The user may also want to define goal positions
|
|
of the agents, or a roadmap to guide the agents around obstacles. This is not done
|
|
in <b>RVO2-3D Library</b>, but needs to be taken care of in the user's external
|
|
application.
|
|
|
|
The following example creates a scenario with eight agents exchanging positions.
|
|
|
|
\code
|
|
void setupScenario(RVO::RVOSimulator* sim) {
|
|
// Specify global time step of the simulation.
|
|
sim->setTimeStep(0.25f);
|
|
|
|
// Specify default parameters for agents that are subsequently added.
|
|
sim->setAgentDefaults(15.0f, 10, 10.0f, 2.0f, 2.0f);
|
|
|
|
// Add agents, specifying their start position.
|
|
sim->addAgent(RVO::Vector3(-50.0f, -50.0f, -50.0f));
|
|
sim->addAgent(RVO::Vector3(50.0f, -50.0f, -50.0f));
|
|
sim->addAgent(RVO::Vector3(50.0f, 50.0f, -50.0f));
|
|
sim->addAgent(RVO::Vector3(-50.0f, 50.0f, -50.0f));
|
|
sim->addAgent(RVO::Vector3(-50.0f, -50.0f, 50.0f));
|
|
sim->addAgent(RVO::Vector3(50.0f, -50.0f, 50.0f));
|
|
sim->addAgent(RVO::Vector3(50.0f, 50.0f, 50.0f));
|
|
sim->addAgent(RVO::Vector3(-50.0f, 50.0f, 50.0f));
|
|
|
|
// Create goals (simulator is unaware of these).
|
|
for (size_t i = 0; i < sim->getNumAgents(); ++i) {
|
|
goals.push_back(-sim->getAgentPosition(i));
|
|
}
|
|
}
|
|
\endcode
|
|
|
|
See the documentation on RVO::RVOSimulator for a full overview of the
|
|
functionality to specify scenarios.
|
|
|
|
\section ret Retrieving Information from the Simulation
|
|
|
|
During the simulation, the user can extract information from the simulation for
|
|
instance for visualization purposes, or to determine termination conditions of
|
|
the simulation. In the example program above, visualization is done in the
|
|
updateVisualization(...) method. Below we give an example that simply writes
|
|
the positions of each agent in each time step to the standard output. The
|
|
termination condition is checked in the reachedGoal(...) method. Here we give an
|
|
example that returns true if all agents are within one radius of their goals.
|
|
|
|
\code
|
|
void updateVisualization(RVO::RVOSimulator* sim) {
|
|
// Output the current global time.
|
|
std::cout << sim->getGlobalTime() << " ";
|
|
|
|
// Output the position for all the agents.
|
|
for (size_t i = 0; i < sim->getNumAgents(); ++i) {
|
|
std::cout << sim->getAgentPosition(i) << " ";
|
|
}
|
|
|
|
std::cout << std::endl;
|
|
}
|
|
\endcode
|
|
|
|
\code
|
|
bool reachedGoal(RVO::RVOSimulator* sim) {
|
|
// Check whether all agents have arrived at their goals.
|
|
for (size_t i = 0; i < sim->getNumAgents(); ++i) {
|
|
if (absSq(goals[i] - sim->getAgentPosition(i)) > sim->getAgentRadius(i) * sim->getAgentRadius(i)) {
|
|
// Agent is further away from its goal than one radius.
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
\endcode
|
|
|
|
Using similar functions as the ones used in this example, the user can access
|
|
information about other parameters of the agents, as well as the global
|
|
parameters, and the obstacles. See the documentation of the class
|
|
RVO::RVOSimulator for an exhaustive list of public functions for retrieving
|
|
simulation information.
|
|
|
|
\section manip Manipulating the Simulation
|
|
|
|
During the simulation, the user can manipulate the simulation, for instance by
|
|
changing the global parameters, or changing the parameters of the agents
|
|
(potentially causing abrupt different behavior). It is also possible to give the
|
|
agents a new position, which make them jump through the scene.
|
|
New agents can be added to the simulation at any time.
|
|
|
|
See the documentation of the class RVO::RVOSimulator for an exhaustive list of
|
|
public functions for manipulating the simulation.
|
|
|
|
To provide global guidance to the agents, the preferred velocities of the agents
|
|
can be changed ahead of each simulation step. In the above example program, this
|
|
happens in the method setPreferredVelocities(...). Here we give an example that
|
|
simply sets the preferred velocity to the unit vector towards the agent's goal
|
|
for each agent (i.e., the preferred speed is 1.0).
|
|
|
|
\code
|
|
void setPreferredVelocities(RVO::RVOSimulator* sim) {
|
|
// Set the preferred velocity for each agent.
|
|
for (size_t i = 0; i < sim->getNumAgents(); ++i) {
|
|
if (absSq(goals[i] - sim->getAgentPosition(i)) < sim->getAgentRadius(i) * sim->getAgentRadius(i) ) {
|
|
// Agent is within one radius of its goal, set preferred velocity to zero
|
|
sim->setAgentPrefVelocity(i, RVO::Vector3());
|
|
} else {
|
|
// Agent is far away from its goal, set preferred velocity as unit vector towards agent's goal.
|
|
sim->setAgentPrefVelocity(i, normalize(goals[i] - sim->getAgentPosition(i)));
|
|
}
|
|
}
|
|
}
|
|
\endcode
|
|
|
|
\section example Example Programs
|
|
|
|
<b>RVO2-3D Library</b> is accompanied by one example program, which can be found in the
|
|
<tt>$RVO_ROOT/examples</tt> directory. The example is named Sphere, and
|
|
contains the following demonstration scenario:
|
|
<table border="0" cellpadding="3" width="100%">
|
|
<tr>
|
|
<td valign="top" width="100"><b>Sphere</b></td>
|
|
<td valign="top">A scenario in which 812 agents, initially positioned evenly
|
|
distributed on a sphere, move to the antipodal position on the
|
|
sphere. </td>
|
|
</tr>
|
|
</table>
|
|
|
|
|
|
\page params Parameter Overview
|
|
|
|
\section globalp Global Parameters
|
|
|
|
<table border="0" cellpadding="3" width="100%">
|
|
<tr>
|
|
<td valign="top" width="150"><strong>Parameter</strong></td>
|
|
<td valign="top" width="150"><strong>Type (unit)</strong></td>
|
|
<td valign="top"><strong>Meaning</strong></td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">timeStep</td>
|
|
<td valign="top">float (time)</td>
|
|
<td valign="top">The time step of the simulation. Must be positive.</td>
|
|
</tr>
|
|
</table>
|
|
|
|
\section agent Agent Parameters
|
|
|
|
<table border="0" cellpadding="3" width="100%">
|
|
<tr>
|
|
<td valign="top" width="150"><strong>Parameter</strong></td>
|
|
<td valign="top" width="150"><strong>Type (unit)</strong></td>
|
|
<td valign="top"><strong>Meaning</strong></td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">maxNeighbors</td>
|
|
<td valign="top">size_t</td>
|
|
<td valign="top">The maximum number of other agents the agent takes into
|
|
account in the navigation. The larger this number, the
|
|
longer the running time of the simulation. If the number is
|
|
too low, the simulation will not be safe.</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">maxSpeed</td>
|
|
<td valign="top">float (distance/time)</td>
|
|
<td valign="top">The maximum speed of the agent. Must be non-negative.</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">neighborDist</td>
|
|
<td valign="top">float (distance)</td>
|
|
<td valign="top">The maximum distance (center point to center point) to
|
|
other agents the agent takes into account in the
|
|
navigation. The larger this number, the longer the running
|
|
time of the simulation. If the number is too low, the
|
|
simulation will not be safe. Must be non-negative.</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top" width="150">position</td>
|
|
<td valign="top" width="150">RVO::Vector3 (distance, distance)</td>
|
|
<td valign="top">The current position of the agent.</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top" width="150">prefVelocity</td>
|
|
<td valign="top" width="150">RVO::Vector3 (distance/time, distance/time)
|
|
</td>
|
|
<td valign="top">The current preferred velocity of the agent. This is the
|
|
velocity the agent would take if no other agents or
|
|
obstacles were around. The simulator computes an actual
|
|
velocity for the agent that follows the preferred velocity
|
|
as closely as possible, but at the same time guarantees
|
|
collision avoidance.</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">radius</td>
|
|
<td valign="top">float (distance)</td>
|
|
<td valign="top">The radius of the agent. Must be non-negative.</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top" width="150">timeHorizon</td>
|
|
<td valign="top" width="150">float (time)</td>
|
|
<td valign="top">The minimum amount of time for which the agent's velocities
|
|
that are computed by the simulation are safe with respect
|
|
to other agents. The larger this number, the sooner this
|
|
agent will respond to the presence of other agents, but the
|
|
less freedom the agent has in choosing its velocities.
|
|
Must be positive. </td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top" width="150">velocity</td>
|
|
<td valign="top" width="150">RVO::Vector3 (distance/time, distance/time)
|
|
</td>
|
|
<td valign="top">The (current) velocity of the agent.</td>
|
|
</tr>
|
|
</table>
|
|
|
|
|
|
\page terms Terms and Conditions
|
|
|
|
<b>RVO2-3D Library</b>
|
|
|
|
Copyright 2008 University of North Carolina at Chapel Hill
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
|
|
*/
|
|
|
|
#endif /* RVO_RVO_H_ */
|