Tagged with physx - NVIDIA Developer Forums

AWD for N-wheeled cars

romanmarchenko — Thu, 10 May 2012 09:52:07 -0400

Hi guys. I need to simulate M1126 Stryker ICV, which is 8-wheeled car. But eDIFF_TYPE_LS_4WD or eDIFF_TYPE_OPEN_4WD its not enough to make it truly all-terrain. If I will stop at hill, when front and rear wheels are hanging in air (all vehicle mass pushes on middle wheels), it is almost impossible to move my vehicle from this position - driven wheels are spinning freely. So my question is: Is it possible to apply torque to all wheels and make N-wheeled car truly NWD? Or maybe this feature will be added in future releases (I am using physx 3.2-beta3)? Or maybe it is possible to adapt tank simulation model somehow (but steering mode, according to documentation, is not really applicable to ordinary vehicles)?

Thanks in advance.

PhysX 3.2 Vehicle and Heightfield = crash

Vladimir62 — Sun, 13 May 2012 17:42:55 -0400

Hi!
I have found a bug with vehicle on heightfield.
When vehicle falls down on flat terrain (no matter falling height) - when wheels contact the heightfield - my application crashes with segmentation fault in PxVehicleSuspensionRaycasts() function call at physx::PxsBoardPhaseContextSap::batchUpdate() (from disassembler).
Vehicles work fine with flat plane as ground and another obstacles.
I have found what if the vehicle falls on the terrain not parallel (i.e. with small z axle angle - on the front or rear wheels only) - there are no crash happens and car lands on the terrain successfully and then moves ok. If vehicle lands on 4-wheels at same time, or rear and front wheels (x axle angle) - app crashes.

I'm using SampleVehicleWheelRaycastPreFilter from demo sample and heightfield generation from documentation sample.
Qt + GCC 4.4.3 + Ubuntu 10.04 lts + PhysX LINUX SDK 3.2 beta 2 and 3 (both crashes)

LiveKernelEvent

Michi10 — Wed, 16 May 2012 07:11:50 -0400

Hello support NVIDIA

Since 3 weeks, I have a big problem in the video or games comes with me on the screen such a picture.

[url=http://www.abload.de/image.php?img=foto0089s2dri.jpg][img]http://www.abload.de/thumb/foto0089s2dri.jpg[/img][/url]

After a few minutes, this image comes back.

[url=http://www.abload.de/image.php?img=foto00903gckl.jpg][img]http://www.abload.de/thumb/foto00903gckl.jpg[/img][/url]

Then I looked at the Fehlerrebort me and understand only station so I can make only so enter it you:

Produkt
Windows

Problem
Grafikkartenfehler

Datum
16.05.2012 11:06

Status
Nicht berichtet

Beschreibung
Aufgrund eines Videohardwareproblems ist Windows nicht mehr voll funktionsfähig.

Problemsignatur
Problemereignisame: LiveKernelEvent
Betriebsystemversion: 6.0.6002.2.2.0.768.3
Gebietsschema-ID: 1031

Dateien zur Beschreibung des Problems
WD-20120516-1106.dmp
sysdata.xml
Version.txt

Weitere Informationen über das Problem
BCCode: 117
BCP1: 87FA1510
BCP2: 92358ACE
BCP3: 00000000
BCP4: 00000000
OS Version: 6_0_6002
Service Pack: 2_0
Product: 768_1

I was with my computer at stores where I bought the parts and the graphics card and now even the technician is verwiert and white but not what he do sol my graphics card is only 1 month old. The burden has not revealed the whole PC and the driver version is 296.10 this software I de 5 times and installed but always the same result.

What can that this be it suddenly is pink and one freezes the whole computer?

From the UIG wonder what can be even?

The technician said to me the computer is fine, but what is the error?

I defend glad if you please me an only for the problem very soon can give a response?

With friendly regards
Michael Hirschegger

Physx NxSceneStats2 * getStats2() no result if create fluid with flag .flags &= ~NX_FF_HARDWARE

manking — Wed, 16 May 2012 05:45:28 -0400

Physx 2.8.4
If create fluid with .flags &= ~NX_FF_HARDWARE there is collision, but in
getStats2() all values is 0.

If comment //.flags &= ~NX_FF_HARDWARE
getStats2() return correct result, but there is no collision.

[PhysX 3.1.1] Creation of deformable triangle meshes

reiserzx — Tue, 03 Jan 2012 08:54:25 -0500

Hello,

at first i wish some good 2012.

Beside that important note i also have issues when trying to create deformable meshes with PhysX 3.1.1. I got my vertice and index buffer which i cook a deformable mesh with. The cooking itself runs fine. Yet when i use it to create the PxDeformable i receive an exception from within the call of: CPhysX::g_pPhysics->createDeformable(desc);

The exception is: First-chance exception at 0x503c78f9 in .exe: 0xC0000005: Access violation writing location 0x00000000.

The question i'd like to ask is the following. When the cooking runs fine, is it guaranteed that the resulting PxDeformableMesh is a valid input for createDeformable ? Im just wondering what might be wrong here.

Thanks for the support,
Oliver

Here some adjusted code lines:


PxDeformable* CreateDeformable(PxVec3* vertices, PxU32* indexBuffer, CONST UINT& verticeCount, CONST UINT& indexCount){

	 //prepare mesh description
	PxDeformableMeshDesc desc;
	desc.vertices = pxVertices;
	desc.primitives = pxIndices;
	desc.numVertices = verticeCount;
	desc.numPrimitives = pxPrimitiveCount;
	desc.vertexStrideBytes = sizeof(PxVec3);
	desc.primitiveStrideBytes = sizeof(PxU32) * 3;
	desc.primitiveType = PxDeformablePrimitiveType::eTRIANGLE;

	PxDeformableMesh* dMesh= NULL;
	if(desc.isValid()){
		PxToolkit::MemoryWriteBuffer streamOut;
		if(CPhysX::g_pCook->cookDeformableMesh(desc, streamOut))
		     dMesh = CPhysX::g_pPhysics->createDeformableMesh(PxToolkit::MemoryReadBuffer(streamOut.data));
	}


	 if(result){
		PxDeformableDesc desc = PxDeformableDesc(CPhysX::g_pPhysics->getTolerancesScale());
		desc.deformableMesh = dMesh;
		desc.mass = 1.0F;
		desc.deformableReadDataFlags = PxDeformableReadDataFlag::ePOSITION_BUFFER;

		if(desc.isValid()){
	 	 	//this is the call where the exception occur
			return CPhysX::g_pPhysics->createDeformable(desc);
		}
	}
	return NULL;
}

Trouble installing 2.7 Physx plug-in for Max2012

CDIcthomas — Wed, 14 Mar 2012 14:11:52 -0400

I have downloaded the 2.7 build for max2012-64 but when trying to install the application it fails to find an installation of max2012-64 installed. I do have a licenced version working on this system, but it is on the D: drive. I had a similar problem with the Fume_FX 2012 install but it allowed for me to point to the installation folder to complete the install.

Any work arounds that you know of? I didn't have this problem with 2011 and it is on the same drive as 2012.

Thanks for any help to get this working in max 2012-64

2 questions reguarding PhysX

dartwing17 — Tue, 15 May 2012 10:03:00 -0400

1. Can cooked triangleMeshes be particle drains?

When setting shape->setFlag(physx::PxShapeFlag::ePARTICLE_DRAIN, true) on the TriangleMesh shape, nothing happons

2. How do I get the fluid particle densityBuffer?

I have set the particleReadDataFlags when creating the fluid (particleSystemDesc.particleReadDataFlags |= physx::PxParticleReadDataFlag::eVELOCITY_BUFFER | physx::PxParticleReadDataFlag::eDENSITY_BUFFER;)
and get the density per particle like this:

physx::PxParticleFluidReadData* rd = pf->lockParticleFluidReadData();
if (rd->validParticleRange > 0)
{
physx::PxStrideIterator particleFlags(rd->flagsBuffer);

// iterate over valid particle bitmap
for (physx::PxU32 w = 0; w <= (rd->validParticleRange-1) >> 5; w++)
{
for (physx::PxU32 b = rd->validParticleBitmap[w]; b; b &= b-1)
{
physx::PxU32 index = (w << 5 | physx::lowestSetBit(b));
const physx::PxF32& density = rd->densityBuffer[index];

if (particleFlags[index] & physx::PxParticleFlag::eVALID)
{
particleDensityArray.push_back(density);
}
}
}
}
rd->unlock();

but doing this causes the runtime error:

c:\p4\px31_installers\sw\physx\release\physx-3.1\standard_build\physxsdk\sdks\physx\src\particles\NpParticleFluidReadData.h (64) : invalid operation : PxParticleReadData access through PxParticleBase::lockParticleReadData() while its still locked by last call of PxParticleBase::lockParticleReadData().

I dont understand why I get this error. I do the same procedure for getting position and velocity, and that works flawless.

- Andy

PS: I use Physx 3.1.1

Update: Forget question nr. 2. I think I understand now why it doesnt work. The densitybuffer is only valid after the particle fluid has been simulated. Meaning if I for example put a boolean in my last if-check which is false at startup, and set it to true while the simulation is running then it works.

But im still wondering if its possible to make a trianglemesh a particle drain... still cant make that work

Help adding external force to particles

dartwing17 — Sat, 12 May 2012 10:29:45 -0400

Hi,

I have run a wind simulation in Flow-3D and have exported a set of wind-vectors, which describe
a position and a velocity. I want to use these wind-vectors in my particle system, so that when a particle is inside a wind-vector position (lets say +- 0.5), the velocity of the wind-vector should be added to the particle.

I have implemented a way to do this, but it is very inefficient. I was just wondering if anyone had any suggestion on how to make the algorithm more efficient.

This is my implementation (sorry for the ugly code):

glm::vec3 checkWindPosition(glm::vec3 particlepos)
{
for(int i = 0; i < flowWindGrid.size(); i++)
if(particlepos.x < flowWindGrid[i].position.x+0.5f && particlepos.x > flowWindGrid[i].position.x-0.5f
&& particlepos.y < flowWindGrid[i].position.y+0.5f && particlepos.y > flowWindGrid[i].position.y-0.5f
&& particlepos.z < flowWindGrid[i].position.z+0.5f && particlepos.z > flowWindGrid[i].position.z-0.5f)
return flowWindGrid[i].velocity;
return glm::vec3(99,99,99);
}

void update()
{
physx::PxParticleFluidReadData* rd = pf->lockParticleFluidReadData();
if (rd->validParticleRange > 0)
{
physx::PxStrideIterator particleFlags(rd->flagsBuffer);
// iterate over valid particle bitmap
for (physx::PxU32 w = 0; w <= (rd->validParticleRange-1) >> 5; w++)
{
for (physx::PxU32 b = rd->validParticleBitmap[w]; b; b &= b-1)
{
physx::PxU32 index = (w << 5 | physx::lowestSetBit(b));
const physx::PxVec3& position = rd->positionBuffer[index];

if (particleFlags[index] & physx::PxParticleFlag::eVALID)
{
glm::vec3 newvelocity = checkWindPosition(glm::vec3(position.x,position.y,position.z));
if(newvelocity != glm::vec3(99,99,99))
{
windIndexBuffer.push_back(index);
windForce.push_back(physx::PxVec3(newvelocity.x,newvelocity.y,newvelocity.z));
}
}
}
}
}

rd->unlock();

physx::PxStrideIterator forceBuffer(&windForce[0]);
physx::PxStrideIterator indexData(&windIndexBuffer[0]);
pf->addForces(windForce.size(), indexData, forceBuffer, physx::PxForceMode::eFORCE);
}

Move only child in the Joint drive.

Booster — Fri, 11 May 2012 14:36:31 -0400

Hello everyone.
Is it possible to move only child actor of joint through joint drive? Thanks in advance.

Installing Apex / physx on a Maya 2012 deployment

Vustadumas — Mon, 14 May 2012 15:24:49 -0400

When trying to install the Physx plug-ins, in Maya 2012 (64-bit), it says that Maya is not installed. Our deployment isn't installed in the Maya default folder structure. Could this be the cause of the error?

Here's the error...

PhysX For Autodesk Maya 2012 64bit is not installed.
Setup requires the version of Autodesk Maya of
matching version and bits to be installed prior to
installation of this product. Setup will now exit.

Thanks for any help!

Corey

What's the problem with materials and which side they are connected to deserialization problems?

Kosmos — Sun, 13 May 2012 11:41:08 -0400

Hello everyone
I am trying to serialize some triangle meshes in scene from one application and deserialize them in another.
So, i have next code for serialization purposes:
PxSDK is PxPhysics object pointer
mPxScene is PxScene object pointer


class FileSerialStream : public PxSerialStream //class for writing serialized file
{
public:
    FileSerialStream(std::string file_name) { ofile.open(file_name, std::ios::binary); }

    ~FileSerialStream()
	{
		ofile.flush();
		ofile.close();
	}

    virtual void storeBuffer(const void *buffer, physx::PxU32 size)	{ ofile.write(reinterpret_cast(buffer), size); }
	virtual physx::PxU32 getTotalStoredSize(void)					{ return ofile.tellp(); }

private:
	std::ofstream ofile;

    // Disable unimplemented operations
    FileSerialStream( const FileSerialStream & );
    FileSerialStream& operator=( const FileSerialStream & );
};

void SerializeScene()
{
	PxCollection *mCollection = PxSDK->createCollection();

	for(unsigned int i = 0; i < movable_entries.size(); i++) //run though physical objects in scene
	{
		if (movable_entries[i].mController != NULL || movable_entries[i].IsCameraController) //if object is character controller
			continue; //we skip it

		movable_entries[i].mActor->collectForExport(*mCollection); //add object to collection
	}

	FileSerialStream fss("serialized_map.bin");
	mCollection->serialize(fss); //serialize
	PxSDK->releaseCollection(mCollection);
}

First of all, i see major difference in file size between this serialization and creating RepX file from PVD. If i save objects in frame to RepX file size is 433kb, but with binary serialization it 14kb (i don't have any idea how it can store all that figures points in such amount of data)
Anyway... let's assume that serialization successed.

Deserialization apllication code:

void DeserializeScene(const char* filename)
{
	FILE* fp = NULL;

	if( (fp = fopen(filename, "rb")) )
	{
		fseek(fp, 0, SEEK_END);
		PxU32 fileSize = ftell(fp);
		fseek(fp, 0, SEEK_SET);

		PX_ASSERT(fileSize != 0);
		void* mem = malloc(fileSize + PX_SERIAL_FILE_ALIGN);

		void* mem16 = (void*)((size_t(mem) + PX_SERIAL_FILE_ALIGN)&~(PX_SERIAL_FILE_ALIGN - 1));
		fread(mem16, 1, fileSize, fp);
		fclose(fp);

		PxCollection* collection = PxSDK->createCollection();
		collection->deserialize(mem16, NULL, NULL);

		PxSDK->addCollection(*collection, mPxScene);
		PxSDK->releaseCollection(collection);
	}
}

When this function runs i getting next messages in console:
NpRigidStatic | 42 | 4536
NpShape | 42 | 8064
Padding: 168 bytes
C:\p4\px31_installers\sw\physx\Releases\PhysX-3.1\standard_build\PhysXSDK\SDKs\PhysX\src\NpPhysics.cpp (733) : invalid operation : resolveMaterialPtr: material not found.
PVD shows empty scene, so... objects isn't load succesfully.
From messages we see something about invalid operation : resolveMaterialPtr: material. Wat is it? What should be done about it? There is nothing about it in built-in guides.
I am using PhysX-3.1.2_PC_VC10_SDK_Core

How to deal right with BoxCharacterController Extends in PhysX 3.2? Or why they are wrong in PVD?

Kosmos — Mon, 14 May 2012 13:25:18 -0400

Hello everyone. After upgrading from physx 3.1 to physx 3.2 i run into weird things about extends of character controllers.
This all can be described by next code:

		PxBoxControllerDesc desc;
		desc.position = toPxExt(start_pos);
		desc.halfForwardExtent = 2;
		desc.halfHeight = 4;
		desc.halfSideExtent = 8;
		desc.contactOffset = 0.01f;
		desc.slopeLimit = cosf(45.0f * (3.14159265f / 180)); //converting 45 degrees to radians
		desc.stepOffset = 0.01f; 
		//desc.upDirection = PxVec3(0, 1, 0); //don't helps

and picture that i attached here.

If we see on box bigger sides, we notice that the most big side is vertical, but are we remember this desc.halfHeight = 4;? Vertical side of box must be second in size after sideExtend, but it looks for me they are misplaced.

Does i doing something wrong by hoping that halfHeight is vertical dimension of box or... there is something wrong?

i am using PhysX-3.2.0_PC_SDK_Core now

PhysX 3.1 and PxController

ahojmar — Tue, 01 May 2012 11:57:32 -0400

Hi,

I am using PhysX 3.1 and PxController. Problem is with interaction of those objects.

1) In my engine, every object has PxRigidActor body (static or dynamic). If I add new object to the scene, body is automaticly created. But for some objects I need to use PxContoller, which has its own PxRigidDynamic. So question is, what should i do with old one.
Should i remove it from scene ? If I keep it, physics is weird for this object.
2) I need to rotate object with PxController. There is no way within conrtoller, how to do it. So I take PxRigidDynamic pointer and rotate it with setGlobalPose. Hovewer, in PhysX SDK documentation, there is written that this pointer should be used only for const operations. So, how to deal with this problem "correctly" ?

Thanks

Non stop bouncing NxWheelShape suspension using PhysX 2.8.1 / 2.8.3

Jon Bcklund — Wed, 09 May 2012 07:56:51 -0400

Hi!

Using PhysX API 2.8.1 (Also tried 2.8.3), I have modeled a Wheel Loader vehicle. The vehicle consists of 4 actors building the articulated vehicle body and lift arm. It has one NxWheelShape in each corner. Not looking at the friction (I'm fine with high friction tyres for now, do not need any fancy curve) whatever values I give to the wheelshapes I cannot get them to act stable.

The suspension itself acts just as I want it with good spring and damper effect when I drive around, so far, so good. The problem is that the cannot stand still. If the vehicle stands on an uneven ground, so that one or two wheels are in the air, or almost in the air, the vehicle (suspension) starts to bounce and never stops, as it get more and more energy all the time, even though I have working damping in the suspension. The effect gets even worse if I change the suspension.targetValue to anything above 0.0, then the vehicle bounces like a maniac from the start, where it should just rest silently on the ground.

To me the bug seems too obvious to have slipped through, so I'm hoping I've missed something fundamental here. Any help would be very appreciated.

Heres some values current going in to the wheel shapes which looks good when driving around:

Total actor weight: about 30 tons (also tried to change this to lower tonnage)

WheelRadius 0.75
Wheel Suspension Travel 0.35
Suspension Spring 1100000
Suspension Damper 10000
Suspension TargetValue 0.0
No special wheelshape flags set
Tire StiffnessTo Side 5000000.0
Tir eStiffnessTo Front 500000.0

Thanks!
-Jon

Can I incorporate volume data into PhyX?

chloe5608 — Wed, 09 May 2012 11:53:28 -0400

Hi, I'm new to PhysX and I'm trying to do some fluid simulation with volumetric data. I have my old SPH code written in C++ and the particles can collide with volume data. But I'm thinking of apply phsX for my simulation since I want to use more particles and my old implementation of SPH is not quite robust.

Can I extract the property of particle(e.g. position, velocity, acceleration) and do the collision myself then send the data back? All the volume data is available on both CPU and GPU(texture).

A question about Particles in the samples of the SDK

renwairen — Wed, 09 May 2012 23:28:02 -0400

I'm a new learner. Now I'm reading the code of the samples in the SDK. In the "SampleParticles", I try to change something to make it look like the real lake and fall. I change the "PxParticleFluid* SampleParticles::createFluid", then when I press "1" and throw a box,the box can collide with the fluid. But the lake cannot move like water, I try to change the code in "PxParticleSystem* SampleParticles::createParticleSystem", it still cannot collide with the box, how should I do? Then if I want to show the effect of the collision between the fall and the lake, how should I do? (My English is so so. Thank you very much.)

Latest 3.2.0 will crash in several seconds (64bit), Bug!!??

yeahy — Sat, 12 May 2012 22:18:45 -0400

I download the physX 3.2 and upgrade my code from PhysX 3.1, I found my application will crash when just run several seconds!! I think it' num16K datablock issue;

I mean, the 64 bit one.

So, I openned the \Bin\win64\samples.exe for testing, and run it.

when I click "1" and hold it for emit the RBDs, just need 3~4 seconds, the system will crash

Is that a bug or my machine issue??? I really need your help soon! Now I have to go back to version 3.1.................

Also this problem is never fixed since half a year:
http://forums.developer.nvidia.com/devforum/discussion/3191/bug-physx-3-1-joint-strange-movement-video

Thanks,
--Yeah

Individual shape mass in a compound shape actor (PhysX 3)

silverevo03 — Fri, 11 May 2012 13:08:02 -0400

I have recently switched from PhysX 2.8.4 to 3.2 and I have been unable to find in the documentation where I can set individual mass for shapes. It appears that you have to set the entire mass for an actor, and then use a Vector3, or intertia tensor to define where center of mass is, where as in PhysX 2.8.4 you could define the mass for each shape inside the actor, and total mass and intertia tensor were calculated from the individual masses.

Does anybody know where the method to calculate mass for compound actors based on individual shape mass is located in the samples or documentation? Another problem is PxGeometry, nor PxShape reference any type of mass member, which leads me to believe that the functionality was removed in 3.x

Thanks for the help

-- SilverEvo03

Trouble installing 2.7 Physx plug-in for Max2012

Thomas Bade — Thu, 10 May 2012 13:12:41 -0400

I have downloaded the 2.7 build for max2012-64 but when trying to install the application it fails to find an installation of max2012-64 installed.
Installation is on Drive C, but some paths are on D, for example autoback...
I have same problems as CDIcthomas posted on March 14:
http://forums.developer.nvidia.com/devforum/discussion/5921/trouble-installing-2-7-physx-plug-in-for-max2012/p1
Also there was no real solution. Please help, we need the plugin in so bad for a production.

Thanks in advance

[PhysX 3.2 beta-3] Cannot convert binary data from 32 to 64 bit

Budai — Wed, 25 Apr 2012 18:52:35 -0400

Hi,

I have been experiencing an access violation when I deserialize a repx file, convert it from 32 to 64 bit, and deserialize the result on a 64-bit platform.

I have attached a vs2010 project as a test case. You might have to check the platform toolset on x64, as I'm using vs express.

Thank you for your time,
Budai

debug version of PhysX .libs?

johanneslang2718281828 — Sat, 31 Dec 2011 15:37:31 -0500

I am getting the linker error

"PhysX3CharacterKinematic.lib(CctCharacterControllerManager.obj) : error LNK2038: mismatch detected for '_ITERATOR_DEBUG_LEVEL': value '0' doesn't match value '2'"

when building my application in debug mode.

After some googleing, I found out that this is caused when debug and non-debug libs are used together. So is there a debug version of PhysX3CharacterKinematic.lib etc.?

Apex clothing plugin for Maya, maxDistance painting unuseable.

ktacreations — Sat, 05 May 2012 22:23:59 -0400

I use the Apex clothing plugin v2.7 for Maya 2012 x64 and the maxDistance painting is completely unuseable. Selecting 'paint' from the clothing menu gives an error and clicking the "paint" button in the edit clothing window brings up the paint tool but defaults to selecting the entire mesh instead of the specific vertexes I had selected. It worked relatively fine in 2.6, albeit with random crashes, as expected for anything that touches maya.

Then flood seems to simply refuse to do anything and the color feedback is nonsensical. The single forum post (http://forums.developer.nvidia.com/devforum/discussion/comment/16506#Comment_16506) I found on this topic just said that painting isnt working in this version and to go back to 2.6. Is that true? Is work still being done on this plugin?

Many thanks for your time.

MassFX warning with 3ds Max scenes installed with PhysX

hotdoggyurkeyam — Tue, 08 May 2012 14:39:23 -0400

Hi, I get a warning when I open another max scene on another machine here at work, it says:

“The MassFX authored in this file was created with a newer version of the plugins. Forward compatibility is not supported so things might not behave properly.”

I am currently using PhysX for Max version: 2.7.1.0202.1800 and PhysX System Software 9.11.0621 abd I have noticed inside my Max install location, MassFX has been moved into a folder named "DISABLED_BY_NVIDIA_PHYSX_PLUGINS"

Third party plugins installed for Max being used in the scene are: Rayfire 1.57.10; Orbaz Particle Flow Box #2 ver. 1.07 and #3 ver. 1.53. I’ve gotten this warning in scenes saved from another PC, opened in another, and not even using any PhysX or PhysX capable plugins.

Thanks.

PS3 - UE3 - Unrelated NxD6Joints apparently affecting each other.

JoeFBoyd — Tue, 03 Apr 2012 19:51:46 -0400

Hello,

We have encountered a strange issue in our game where completely unrelated NxD6Joints appear to be affecting each other and I do not know why. Let me describe the situation:

We have some game objects that are simulated as NxActors. The player can pick up these objects. This is implemented by attaching an NxD6Joint to the object and to an anchor. The anchor is a kinematic body, shaped like a sphere, with collision disabled. As the player moves around, we simply move the anchor point and the object the player is holding naturally follows the anchor point. When the player drops the object, we release it from the joint.

There is another separate game object that functions like a springboard. It has an NxActor that is shaped like a flat platform. This actor is anchored to the world via another NxD6Joint in such a way that the platform moves up and down like a springboard.

The issue that is occuring is that whenever the player pick up any object in the game, this appears to affect the stiffness of ALL the springboards in the scene regardless of where they are. The springboard platforms all suddenly move to a new equilibrium point. It appears that either the springboard stiffness is changed or the mass of the platform is changed.

I am able to provide a VRD dump of the issue occurring (though I seem unable to attach it to forum posts). The odd thing is that in the VRD I examined the frames immediately before and after an object was picked up, and I did not observe any change in the properties of the either the springboard's platform NxActor or its NxD6Joint that would cause this behavior. The joint itself has no properties change between the frames (the attachment points do not move, the stiffness does not change, etc.). The only properties that change on the platform actor are its velocity and center of mass. Its density and mass do not change. The platform and the held object are not in physical contact and are not connected in any way (such as by another joint). So I'm not sure what would be causing the observed behavior as nothing I see physically explains the cause of the motion.

This issue only occurs on PS3. It does not occur on PC or XBox 360. Our PhysX version is 284.A6 and our game uses UnrealEngine3.

Any help is appreciated.

debug render

quaikohc — Wed, 02 May 2012 09:13:01 -0400

hi,
i am using PxRenderBuffer in my editor to visualize physx scene, i wan't to draw some shapes with different color (e.g. few shapes selected by the user), is it possible to do this using current api?

How to retrieve faceID(original) of TriangleMesh from triangleID(internal)?

DrawPixel — Mon, 16 Apr 2012 07:23:14 -0400

Such as the title, in Physx 2.8.X, Thank you

3ds max 2012 exporting rigid-body to nxs

doboszsite — Fri, 04 May 2012 15:09:09 -0400

Hello,
I'm trying my best to export just one rigid-body from 3ds max 2012 to nxs. It is my believe that this is PhysX rigid-body format, if its not please let me know. Anyway, there is only 3 export type options: nxb, xml(nxusteam) and Collada. How do I deal with this problem. My physic engine wrapper(NxOgre) can load only nxs file type. Thank for help.

Performance problem

stigrus — Wed, 18 Apr 2012 10:00:41 -0400

I have a scene where a large objects is moving through an area with many smaller objects and the performance is not as high as I need it to be. To alleviate this a bit i make objects "far" away from the large one kinematic and put them to sleep. This helps, but the performance is still not good enough.

I tried putting the kinematic objects in aggregates with self collision turned off, but this did not help either. It actually ran slower when doing this.

Any ideas or tip for how to increase the performance is appreciated :)

All objects are convex or compound of convexes.

forceLimit is actually an impulse limit

shanedthsthbsthbtntn — Fri, 23 Mar 2012 07:10:57 -0400

Referring to line 313 of ExtConstraintHelper in the 3.2.0 beta I noticed the following line
c->minImpulse = -drive.forceLimit;

This seems inherently wrong and indeed the reason I stumbled upon it was I was trying to work out why my constraint was exerting far more than its maximum force (60 times more if ticking at 60Hz).
Now that I am aware of this issue I am able to work around it but is this by design? Is it simply a naming issue? Is it likely to be resolved in future? Would this change necessitate code changes or silently alter the behavior of my code?

how do i bake a simulation for APEX clothing in 3ds max?

pumbama — Sun, 06 May 2012 04:13:44 -0400

Am aware of the options "bake selected" and "bake all" but i dont know how to use them......what i did is start simulation and then pressed bake all....
when it does it, it shows the physx baking etc but nothing changes...none of the simulations are baked.....this is on the physx example given by nvidia for 3dsmax...can you tell me the method
http://i49.tinypic.com/2qlzu5i.png
http://i47.tinypic.com/11c45xh.jpg

Why physx acting so weird..(for 3dsmax 2012) it crashes randomly and doesnt simulate proper

pumbama — Sat, 05 May 2012 07:29:39 -0400

I donwloaded the Physx apex tut from http://supportcenteronline.com/ics/support/default.asp?deptID=1949
When i opened a day ago..it worked now it just never simulates properly....it shows this now...
http://i46.tinypic.com/15p1oxh.png
insted of this
http://i50.tinypic.com/ivuyqd.jpg
Also it crashes quite frequently when using dynamic/kinetic rigid bodies for simulation..can any1 suggest a solution as to why this is hapenning...PS..it worked perfectly for one day...
I have installed physx system software as well....my pc spec are I7 860 2.8ghz 8gb ram...its jus a simple simualtion of a flag example you provided...it just doesnt work nor do any other apex clothing examples for 3dsmax 2012...

PhysX 3.1 PxController move through PxRigidStatic (the floor)

Charli3 — Sun, 22 Apr 2012 18:04:00 -0400

Hi,
I have a problem with the character controller. It moves through the floor when I try to move it using:
m_pPxController->move(physx::PxVec3(0,-9.81f,0)*dt, 0, 0, cf);
The code for the floor is:

physx::PxRigidStatic* plane = m_pPxPhysics->createRigidStatic(pose);
	physx::PxShape* shape = plane->createShape(physx::PxPlaneGeometry(), *pMaterial1);
	shape->setFlags(physx::PxShapeFlag::eSIMULATION_SHAPE | physx::PxShapeFlag::eUSE_SWEPT_BOUNDS | physx::PxShapeFlag::eSCENE_QUERY_SHAPE);
	m_pPxScene->addActor(*plane);

I am sure it's working because the other actors (RigidDynamic) in the scene are colliding with it. They are also colliding with controller. The controller is just not colliding with the shape of the floor. I have a custom filtershader and the function is not even called when the controller goes through the floor.
Do you have an idea why?
Thanks!
Charlie

Default material in the new Scene.

Booster — Thu, 26 Apr 2012 15:28:04 -0400

Hello. When we create new physical scene than it has one material. Why is it? How can we don't create that material? For some reason we can't delete that material. Again why? Thank you in advance.
PhysX 2.8

3DS Max collision mesh convertion into PhysX actor

SoulSharer — Sat, 24 Mar 2012 07:13:59 -0400

Hello there, I wonder if someone could help with this subject.

I want to create an actual model in 3Ds Max and a collision mesh (made of primitives, ie boxes and spheres) that will accompany it. And then export it so that PhysX will use collision mesh and decompose it to primitives and form an actor from them.

How would I decompose and make this PhysX Actor from a primitives? Thanks in advance!

this youtube video shows what I'm looking for: [youtube]

Problem with DirectX and PhysX 3

rwirz — Wed, 18 Apr 2012 14:04:23 -0400

Hi,

I can run in my computer PhysX 2.X (Samples in OpenGL) and PhysXViewer (DirectX).
However, when I try to run PhysX 3.X Samples, the samples crash.
I invetigate and my computer dont have Hardware Vertex, so I change to Sofware Vertex (In the code). But a new error appear in CreateVertexShader, so I dont run the samples.

How can i run the samples in OpenGL?

Thank you

NxScene::linearOBBSweep

sph — Tue, 24 Apr 2012 13:29:07 -0400

Hey guys,
I'm using a linearCapsuleSweep to determine the correct position for my entity.


NxCapsule capsule;
capsule.p0 = NxVec3(m_vPos.x, m_vPos.y, m_vPos.z + 100.f);
capsule.p1 = NxVec3(m_vPos.x, m_vPos.y, m_vPos.z + 200.f);
capsule.radius = 50.f;
NxU32 hits = gScene->linearCapsuleSweep(capsule, NxVec3(0, 0, -1000), NX_SF_STATICS, NULL, 1, &result, NULL);

Unfortunately some of my entities have a box controller and are therefore dropping through the floor when the ground is a little bumpy. So I tried a linearOBBSweep.


NxBox box;
box.center = NxVec3(m_vPos.x, m_vPos.y, m_vPos.z + 150.f);
box.extents = NxVec3(50.f, 50.f, 50.f);
NxU32 hits2 = gScene->linearOBBSweep(box, NxVec3(0, 0, -1000), NX_SF_STATICS, NULL, 1, &result, NULL);

But the linearOBBSweep is never hitting anything! I'm running them directly after each other. The capsule is always hitting at the same spot, the box is never hitting anything!
Anyone ever had this problem?

PhysX Version 2.8.4

Thx for your help!

physx debugger and collision group

bekounet — Wed, 25 Apr 2012 05:25:41 -0400

hello, a simple question here,

i'm dynamically set the collision group for NxShape of a rigidbody in my project.
But the debugger does not see any change for my Actor.

Is there anything that can override my collision group ?
thx

Resize cloth on runtime?

mruce — Mon, 02 Apr 2012 16:14:44 -0400

Is it possible to scale PhysX cloth on runtime (witohut cooking)?

Is nvpx.CreateConvexHull() broken in MassFX 2013 and PhysX 2.71+ for 3ds Max?

wallworm — Fri, 13 Apr 2012 20:55:48 -0400

A function I've been using in a MAXScript tool in 3ds Max has utilized the nvpx.CreateConvexHull() method from MassFX/PhysX. But when I installed PhysX 2.71 in 3ds Max 2012 to accomodate the latest Rayfire, it stopped working. Then, this week, when I tested this method in a vanilla install of 3ds Max 2013, the method still fails to work.

Here is a simple example code that fails now (in MAXScript):


/*Make a teapot*/
tp = TeaPot()

/*convert teapot to mesh to pass into PhysX function*/
ConvertToMesh tp

/*Create an empty Editable_mesh to store the new hull*/
newnode = Editable_mesh() 

newnode.mesh = nvpx.CreateConvexHull tp 44 0 --Exception happens here! 

update newnode

I also have a thread on the the Area about this.

Character controller and kinematic objects collision

romanmarchenko — Fri, 27 Apr 2012 18:05:51 -0400

Guys, is there any way to prevent character controller kinematic capsule to penetrate other kinematic object? I have physx vehicle, that remains in kinematic state till player enters it using keyboard button. When player decide to drive, vehicle switched to normal dynamic mode (non-kinematic). My task is to block character from moving through vehicle mesh when it is in kinematic mode (non-drivable yet).

Thanks in advance.

DirectX integration: What happened to getGlobalPose().getColumnMajor44()?

Daniel Sefton — Wed, 25 Apr 2012 21:42:51 -0400

Hi,

I've been trying to implement PhysX 3.2 (Beta 3) with DirectX, and one of the problems I came across is how to sync DirectX meshes with PhysX shapes. It's often recommended to use the getColumnMajor44() function of getGlobalPose() like so:

D3DXMATRIX d3dMat;
actor->getGlobalPose().getColumnMajor44(d3dMat);
g_pd3dDevice->SetTransform(D3DTS_WORLD, &matWorld);

But apparently this function is no longer existant. Instead I saw that using .q and .p to obtain vector and quaternion positions was the new way, so I tried:

PxTransform pose = actor->getGlobalPose();
D3DXMatrixRotationQuaternion(&mMatRotate, &MappingsD3D9::makeD3DXQuat(pose.q));
D3DXMatrixScaling(&mMatScale, scale.x, scale.y, scale.z);
D3DXMatrixTranslation(&mMatTranslate, pose.p.x, pose.p.y, pose.p.y);
mMatWorld = mMatRotate * mMatScale * mMatTranslate;
mRenderSystem->getD3D9Device()->SetTransform(D3DTS_WORLD, &mMatWorld);

It sort of works... But (the rotations) are totally messed up. When a shape starts rotating the mesh goes in all sorts of crazy offset positions. It may be to to with the fact that PhysX uses a right-hand coordinate system, whereas DirectX's is left (the getColumnMajor44() function solved that before).

If someone could point me in the right direction, I would appreciate it.

Cheers.

Best way to extract scene texture and geometry info from physx API ?

dgermain — Wed, 25 Apr 2012 14:26:03 -0400

I'm new to physX, and I'm building a simple proof of concept here for an application.
I need to extract 3d information of a destroyed object and save it into another format.

I'm currently able to reconstruct a 3d scene of the destroyed object, but I can't find information related to the texture, and ( texture mapping on polygons ).

In short:
- I'm currently accessing actors through a NxApexScene:

m_apexScene->getPhysXScene()->getActors();

- I cycle through the actors, extracting the Mesh and Pose info using the NxConvexMeshDesc describing the pieces in the scene.

So I have a nice untextured destroyed scene in my output object.

I understand that I'm probably not accessing the information at the right place in the API, and that's why I don't have the texture information. But I cannot find a better place at the moment.

Any hint would be appreciated to where I should look to extract the geometry AND the texture/UV information for the scene from the API.

Thanks a lot !

.Apx/apb file format specification

dgermain — Thu, 26 Apr 2012 09:24:50 -0400

I was thinking about creating my own destructible assets without using physxLab.

But I cannot find an official .apx/.apb file format specification.

Is there information/documentation available on the file format ?

Thanks !

Linking problem with PhysX 3.1 (Ubuntu 11.04 64-bits, g++-4.6)

makfly — Fri, 04 Nov 2011 14:51:28 -0400

I have the same problem as under http://forum-archive.developer.nvidia.com/index.php?showtopic=6907

But I've added lines for linker:
-lLowLevelCloth
-lRepXUpgrader3

In PhysX 3.0, there was required -lPhysX3MetaData but this lib doesn't exist in PhysX-3.1_LINUX_SDK_Core.zip

My output is something like this:


g++ -L/home/krzysiek/Programy/PhysX-3.1_LINUX_SDK_Core/SDKs/lib/linux64 -o "PhysXTest"  ./src/PhysXTest.o   -lglut -lGL -lGLU -lPhysX3Cooking -lPhysX3 -lSimulationController -lLowLevel -lLowLevelCloth -lPhysXProfileSDK -lPhysX3Extensions -lFoundation -lSceneQuery -lGeomUtils -lPhysX3Common -lPhysX3CharacterKinematic -lPvdRuntime -lRepX3 -lRepXUpgrader3 -lPxTask -lPhysX3Vehicle
/home/krzysiek/Programy/PhysX-3.1_LINUX_SDK_Core/SDKs/lib/linux64/libPvdRuntime.a(PxMetaDataPvdBinding.cpp.o):(.text+0x1b): undefined reference to `physx::PxDeformableGeneratedValues::PxDeformableGeneratedValues(physx::PxDeformable const*)'
/home/krzysiek/Programy/PhysX-3.1_LINUX_SDK_Core/SDKs/lib/linux64/libPvdRuntime.a(PxMetaDataPvdBinding.cpp.o): In function `physx::Pvd::PvdMetaDataBinding::sendAllProperties(PVD::PvdDataStream*, physx::PxScene const*)':
(.text+0x4ac): undefined reference to `physx::PxSceneDescGeneratedValues::PxSceneDescGeneratedValues(physx::PxSceneDesc const*)'
/home/krzysiek/Programy/PhysX-3.1_LINUX_SDK_Core/SDKs/lib/linux64/libPvdRuntime.a(PxMetaDataPvdBinding.cpp.o): In function `physx::Pvd::PvdMetaDataBinding::sendAllProperties(PVD::PvdDataStream*, physx::PxPhysics const*)':
(.text+0x521): undefined reference to `physx::PxTolerancesScaleGeneratedValues::PxTolerancesScaleGeneratedValues(physx::PxTolerancesScale const*)'
/home/krzysiek/Programy/PhysX-3.1_LINUX_SDK_Core/SDKs/lib/linux64/libPvdRuntime.a(PxMetaDataPvdBinding.cpp.o): In function `physx::Pvd::PvdMetaDataBinding::sendAllProperties(PVD::PvdDataStream*, physx::PxMaterial const*)':
(.text+0x5eb): undefined reference to `physx::PxMaterialGeneratedValues::PxMaterialGeneratedValues(physx::PxMaterial const*)'
/home/krzysiek/Programy/PhysX-3.1_LINUX_SDK_Core/SDKs/lib/linux64/libPvdRuntime.a(PxMetaDataPvdBinding.cpp.o): In function `physx::Pvd::PvdMetaDataBinding::sendAllProperties(PVD::PvdDataStream*, physx::PxShape const*)':
(.text+0x63e): undefined reference to `physx::PxShapeGeneratedValues::PxShapeGeneratedValues(physx::PxShape const*)'

Thanks for any help!

PhysX 3.2: LPD3DXMESH to PhysX Scene

CyberKevin — Thu, 08 Mar 2012 23:23:34 -0500

I have looked on the internet and through the forum and I cannot find any references on how convert .x mesh loaded with DirectX as LPD3DXMESH to mesh usable in a PhysX scene through PxTriangleMeshDesc or PxDeformableMeshDesc. The only references that I have found online to do this were for PhysX 2. Even after I tried to change those codes, it still did not work. Is there a way to do this and if so, what is it?

Why would my particles not be updating?

venteras — Tue, 17 Apr 2012 02:53:17 -0400

Hi

I've managed to successfully create particles and assign them positions, velocities and indices. When I lock them for reading I can retrieve the data, but it never changes.

I've tried:
Setting their velocities, setExternalAcceleration and addforce, but they always keep their initial position.

I also set all of these:
setGridSize(3.0f);
setMaxMotionDistance(0.43f);
setRestOffset(0.0143f);
setContactOffset(0.0143f*2);
setDamping(0.0f);
setRestitution(0.2f);
setDynamicFriction(0.05f);
setParticleMass( 1.0f );
setParticleBaseFlag( PxParticleBaseFlag::eENABLED, true );

Is there something I have to do after createParticleSystem in addition to adding it to the scene with addActor?

Thanks

PhysX Lab unable to open .apb files

dgermain — Tue, 24 Apr 2012 09:55:49 -0400

I can import .obj files, save them as .apb, use them in the sample demo without much problems.

However I'm unable to open/import .apb files, neither the files that used in the SimpleDestruction demo nor the files I created/exported with physx Lab.

When I do an 'import 3d Mesh' and try opening a .apb file, I receive no error, but nothing happen in the editor as if I did not do anything.

Is that a known issue, or I am the only one experiencing this problem ?

Thanks,
DG

PhysX 3.2 beta-3 PxBinaryConverter::setMetaData() problem

Budai — Sat, 14 Apr 2012 19:45:02 -0400

Hi,

I am having some problem with the PxBinaryConverter::setBinaryData() function. It gives an access violation when used.


PxCollection *outputBuffers = physics->createCollection();
PxCollection *outputSceneObjects = physics->createCollection();
PxDefaultFileInputData *inputStream = NEW PxDefaultFileInputData(ws2s(fileSystemPath).c_str());
repx::RepXCollection* repxCollection = repx::createCollection(*inputStream, physics->getFoundation().getAllocatorCallback());
repx::RepXCollection::repXCollectionToPxCollections(repxCollection, physics, cooking, physics->getFoundation().getAllocatorCallback(), &stringTable, NULL, outputBuffers, outputSceneObjects);
repxCollection->destroy();

PxDefaultMemoryOutputStream *outputStream = NEW PxDefaultMemoryOutputStream(gDefaultAllocatorCallback);
outputSceneObjects->serialize(*outputStream);

PxDefaultMemoryInputData *thirtyTwoBitData = NEW PxDefaultMemoryInputData(outputStream->getData(), outputStream->getSize());
wstring resourceName = wstring(resourceFilePath) + L"\\" + assetname;
PhysicsOutputStream *sixtyFourBitData = NEW PhysicsOutputStream(resourceName.c_str());
PxBinaryConverter *converter = cooking->createBinaryConverter(&gDefaultErrorCallback);
char* thirtyTwoBitMetaDataBuffer;
char* sixtyFourBitMetaDataBuffer;
unsigned int thirtyTwoBitMetaDataFilesize = 0;
unsigned int sixtyFourBitMetaDataFileSize = 0;
ResourceManager::getSingleton()->getResourceFile()->LoadBufferA(L"metadata\\win32", thirtyTwoBitMetaDataBuffer, &thirtyTwoBitMetaDataFilesize);
ResourceManager::getSingleton()->getResourceFile()->LoadBufferA(L"metadata\\win64", sixtyFourBitMetaDataBuffer, &sixtyFourBitMetaDataFileSize);
PxInputData* thirtyTwoBitMetaData = NEW PxDefaultMemoryInputData((PxU8*)thirtyTwoBitMetaDataBuffer, thirtyTwoBitMetaDataFilesize);
PxInputData* sixtyFourBitMetaData = NEW PxDefaultMemoryInputData((PxU8*)sixtyFourBitMetaDataBuffer, sixtyFourBitMetaDataFileSize);

converter->setReportMode(PxConverterReportMode::eVERBOSE);
converter->setMetaData(*thirtyTwoBitMetaData, *sixtyFourBitMetaData);
//converter->setMetaData("c:\\INW\\data\\testmetadata.win32", "c:\\INW\\data\\testmetadata.win64");
bool convertSuccess = converter->convert(*thirtyTwoBitData, thirtyTwoBitData->getLength(), *sixtyFourBitData);

The above code breaks on converter->setMetaData(...). Attempting to use the file-based version of the function does the same thing.

The output from the error console is attached.

What am I doing wrong?

Thanks,
Budai

[PhysX 3.2, Beta 3] onSleep, onWake are not invoked

LeBoozer — Wed, 11 Apr 2012 11:09:03 -0400

Hi,

I got a new problem. I use the two callbacks "onSleep" and "onWake" for certain update scenarios.
The problem is, those two callbacks are not invoked by PhysX, "onContact" works correct.
PxRigidDynamic::isSleeping works also properly!

I overwrite "PxSimulationEventCallback" and set my callback normally to PhysX.
(desc.simulationEventCallback = this);

Is there a certain reason why those callbacks aren't called, but "onContact" is?
Thx in advance!