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//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// * Neither the name of NVIDIA CORPORATION nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Copyright (c) 2008-2018 NVIDIA Corporation. All rights reserved.
// Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
// Copyright (c) 2001-2004 NovodeX AG. All rights reserved.
#include "SnippetVehicleCreate.h"
#include "SnippetVehicleTireFriction.h"
#include "SnippetVehicleSceneQuery.h"
namespace snippetvehicle
{
namespace tank
{
void computeWheelCenterActorOffsets
(const PxF32 wheelFrontZ, const PxF32 wheelRearZ, const PxVec3& chassisDims, const PxF32 wheelWidth, const PxF32 wheelRadius, const PxU32 numWheels, PxVec3* wheelCentreOffsets)
{
//chassisDims.z is the distance from the rear of the chassis to the front of the chassis.
//The front has z = 0.5*chassisDims.z and the rear has z = -0.5*chassisDims.z.
//Compute a position for the front wheel and the rear wheel along the z-axis.
//Compute the separation between each wheel along the z-axis.
const PxF32 numLeftWheels = numWheels/2.0f;
const PxF32 deltaZ = (wheelFrontZ - wheelRearZ)/(numLeftWheels-1.0f);
//Set the outside of the left and right wheels to be flush with the chassis.
//Set the top of the wheel to be just touching the underside of the chassis.
for(PxU32 i = 0; i < numWheels; i+=2)
{
//Left wheel offset from origin.
wheelCentreOffsets[i + 0] = PxVec3((-chassisDims.x + wheelWidth)*0.5f, -(chassisDims.y/2 + wheelRadius), wheelRearZ + i*deltaZ*0.5f);
//Right wheel offsets from origin.
wheelCentreOffsets[i + 1] = PxVec3((+chassisDims.x - wheelWidth)*0.5f, -(chassisDims.y/2 + wheelRadius), wheelRearZ + i*deltaZ*0.5f);
}
}
void setupWheelsSimulationData
(const PxF32 wheelMass, const PxF32 wheelMOI, const PxF32 wheelRadius, const PxF32 wheelWidth,
const PxU32 numWheels, const PxVec3* wheelCenterActorOffsets,
const PxVec3& chassisCMOffset, const PxF32 chassisMass,
PxVehicleWheelsSimData* wheelsSimData)
{
//Set up the wheels.
PxVehicleWheelData wheels[PX_MAX_NB_WHEELS];
{
//Set up the wheel data structures with mass, moi, radius, width.
//Increase the damping on the wheel.
for(PxU32 i = 0; i < numWheels; i++)
{
wheels[i].mMass = wheelMass;
wheels[i].mMOI = wheelMOI;
wheels[i].mRadius = wheelRadius;
wheels[i].mWidth = wheelWidth;
wheels[i].mDampingRate = 2.0f;
}
}
//Set up the tires.
PxVehicleTireData tires[PX_MAX_NB_WHEELS];
{
//Set all tire types to "normal" type.
for(PxU32 i = 0; i < numWheels; i++)
{
tires[i].mType = TIRE_TYPE_NORMAL;
}
}
//Set up the suspensions
PxVehicleSuspensionData suspensions[PX_MAX_NB_WHEELS];
{
//Compute the mass supported by each suspension spring.
PxF32 suspSprungMasses[PX_MAX_NB_WHEELS];
PxVehicleComputeSprungMasses(numWheels, wheelCenterActorOffsets, chassisCMOffset, chassisMass, 1, suspSprungMasses);
//Set the suspension data.
for(PxU32 i = 0; i < numWheels; i++)
{
suspensions[i].mMaxCompression = 0.3f;
suspensions[i].mMaxDroop = 0.1f;
suspensions[i].mSpringStrength = 10000.0f;
suspensions[i].mSpringDamperRate = 1500.0f;
suspensions[i].mSprungMass = suspSprungMasses[i];
}
}
//Set up the wheel geometry.
PxVec3 suspTravelDirections[PX_MAX_NB_WHEELS];
PxVec3 wheelCentreCMOffsets[PX_MAX_NB_WHEELS];
PxVec3 suspForceAppCMOffsets[PX_MAX_NB_WHEELS];
PxVec3 tireForceAppCMOffsets[PX_MAX_NB_WHEELS];
{
for(PxU32 i = 0; i < numWheels; i++)
{
//Vertical suspension travel.
suspTravelDirections[i] = PxVec3(0,-1,0);
//Wheel center offset is offset from rigid body center of mass.
wheelCentreCMOffsets[i] = wheelCenterActorOffsets[i] - chassisCMOffset;
//Suspension force application point 0.3 metres below rigid body center of mass.
suspForceAppCMOffsets[i]=PxVec3(wheelCentreCMOffsets[i].x,-0.3f,wheelCentreCMOffsets[i].z);
//Tire force application point 0.3 metres below rigid body center of mass.
tireForceAppCMOffsets[i]=PxVec3(wheelCentreCMOffsets[i].x,-0.3f,wheelCentreCMOffsets[i].z);
}
}
//Set up the filter data of the raycast that will be issued by each suspension.
PxFilterData qryFilterData;
setupNonDrivableSurface(qryFilterData);
//Set the wheel, tire and suspension data.
//Set the geometry data.
//Set the query filter data
for(PxU32 i = 0; i < numWheels; i++)
{
wheelsSimData->setWheelData(i, wheels[i]);
wheelsSimData->setTireData(i, tires[i]);
wheelsSimData->setSuspensionData(i, suspensions[i]);
wheelsSimData->setSuspTravelDirection(i, suspTravelDirections[i]);
wheelsSimData->setWheelCentreOffset(i, wheelCentreCMOffsets[i]);
wheelsSimData->setSuspForceAppPointOffset(i, suspForceAppCMOffsets[i]);
wheelsSimData->setTireForceAppPointOffset(i, tireForceAppCMOffsets[i]);
wheelsSimData->setSceneQueryFilterData(i, qryFilterData);
wheelsSimData->setWheelShapeMapping(i, PxI32(i));
}
}
}// namespace tank
PxVehicleDriveTank* createVehicleTank(const VehicleDesc& tankDesc, PxPhysics* physics, PxCooking* cooking)
{
const PxVec3 chassisDims = tankDesc.chassisDims;
const PxF32 wheelWidth = tankDesc.wheelWidth;
const PxF32 wheelRadius = tankDesc.wheelRadius;
const PxU32 numWheels = tankDesc.numWheels;
const PxFilterData& chassisSimFilterData = tankDesc.chassisSimFilterData;
const PxFilterData& wheelSimFilterData = tankDesc.wheelSimFilterData;
//Construct a physx actor with shapes for the chassis and wheels.
//Set the rigid body mass, moment of inertia, and center of mass offset.
PxRigidDynamic* tankActor = NULL;
{
//Construct a convex mesh for a cylindrical wheel.
PxConvexMesh* wheelMesh = createWheelMesh(wheelWidth, wheelRadius, *physics, *cooking);
//Assume all wheels are identical for simplicity.
PxConvexMesh* wheelConvexMeshes[PX_MAX_NB_WHEELS];
PxMaterial* wheelMaterials[PX_MAX_NB_WHEELS];
for(PxU32 i = 0; i < numWheels; i++)
{
wheelConvexMeshes[i] = wheelMesh;
wheelMaterials[i] = tankDesc.wheelMaterial;
}
//Chassis just has a single convex shape for simplicity.
PxConvexMesh* chassisConvexMesh = createChassisMesh(chassisDims, *physics, *cooking);
PxConvexMesh* chassisConvexMeshes[1] = {chassisConvexMesh};
PxMaterial* chassisMaterials[1] = {tankDesc.chassisMaterial};
//Rigid body data.
PxVehicleChassisData rigidBodyData;
rigidBodyData.mMOI = tankDesc.chassisMOI;
rigidBodyData.mMass = tankDesc.chassisMass;
rigidBodyData.mCMOffset = tankDesc.chassisCMOffset;
tankActor = createVehicleActor
(rigidBodyData,
wheelMaterials, wheelConvexMeshes, numWheels, wheelSimFilterData,
chassisMaterials, chassisConvexMeshes, 1, chassisSimFilterData,
*physics);
}
//Set up the sim data for the wheels.
PxVehicleWheelsSimData* wheelsSimData = PxVehicleWheelsSimData::allocate(numWheels);
{
//Compute the wheel center offsets from the origin.
PxVec3 wheelCentreActorOffsets[PX_MAX_NB_WHEELS];
const PxF32 frontZ = chassisDims.z*0.35f;
const PxF32 rearZ = -chassisDims.z*0.35f;
tank::computeWheelCenterActorOffsets(frontZ, rearZ, chassisDims, wheelWidth, wheelRadius, numWheels, wheelCentreActorOffsets);
tank::setupWheelsSimulationData
(tankDesc.wheelMass, tankDesc.wheelMOI, wheelRadius, wheelWidth,
numWheels, wheelCentreActorOffsets,
tankDesc.chassisCMOffset, tankDesc.chassisMass,
wheelsSimData);
}
//Set up the sim data for the tank drive model.
PxVehicleDriveSimData driveSimData;
{
//Set up the engine to be more powerful but also more damped than the default engine.
PxVehicleEngineData engineData = driveSimData.getEngineData();
engineData.mPeakTorque *= 2.0f;
engineData.mDampingRateZeroThrottleClutchEngaged = 2.0f;
engineData.mDampingRateZeroThrottleClutchDisengaged = 0.5f;
engineData.mDampingRateFullThrottle = 0.5f;
driveSimData.setEngineData(engineData);
}
//Create a tank from the wheels and drive sim data.
PxVehicleDriveTank* vehDriveTank = PxVehicleDriveTank::allocate(numWheels);
vehDriveTank->setup(physics, tankActor, *wheelsSimData, driveSimData, numWheels);
//Configure the userdata
configureUserData(vehDriveTank, tankDesc.actorUserData, tankDesc.shapeUserDatas);
//Free the sim data because we don't need that any more.
wheelsSimData->free();
return vehDriveTank;
}
} // namespace snippetvehicle
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