[C++, DX9] NewtonWorldRayCast() doesn't work correctly

[Ripiz]

Code: Select all

float dist = 0;
float _cdecl Hit(const NewtonBody* body, const float* hitNormal, int collisionID, void* userData, float intersetParam){
   if(intersetParam < dist)
      dist = intersetParam;
   return intersetParam;
}

//camera code
      m_TargetPos = loc;
      m_TargetPos.z += 50;
      m_EyePos.x = loc.x + 500 * sin(yrot) * sin(xrot);
      m_EyePos.y = loc.y + 500 * sin(yrot) * cos(xrot);
      m_EyePos.z = loc.z + 25 - 500 * cos(yrot);
      dist = 2;
      NewtonWorldRayCast(world, m_TargetPos, m_EyePos, Hit, 0, 0);
      if(dist <= 1.0f)
         m_EyePos = m_TargetPos + (m_EyePos - m_TargetPos) * (dist - 0.05);


Basically, sometimes RayCast works, sometimes it doesn't.

My CollisionTree (or Trimesh): http://dl.dropbox.com/u/2637453/nwtn/CollisionTree.PNG
If I stand on that "canyon" and move camera into it, ray works perfectly: http://dl.dropbox.com/u/2637453/nwtn/Canyon.PNG
But it doesn't detect anything with those huge triangles: http://dl.dropbox.com/u/2637453/nwtn/Bug.PNG (that's view from underground)

Anyone know how to fix this?

[Julio Jerez]

check carefully, it is unlikelly the ray cast will work in one triangel an dfail other consitntly. you most have a bug.

[Ripiz]

Visual debug mesh and original terrain matches, I don't know what else to check. Any tips?

[Carli]

maybe you could debug my raycast case, too:
viewtopic.php?f=12&t=5914

Basically, sometimes RayCast works, sometimes it doesn't.

both crashes could be caused by the same problem

[Ripiz]

It doesn't crash, just Ray doesn't work.

Heres demo source for demo in which bug is reproducible: http://dl.dropbox.com/u/2637453/nwtn/demo.rar
But you'll need DirectX SDK.

I hope this helps.



P.S. I hope there's not too much mess

[Julio Jerez]

Ok I will check tonight.

[Carli]

It doesn't crash, just Ray doesn't work.

in my linux64 mashine, it does not work, on linux32 it crashes. (i did not test win32 (or maybe it does not work, too))

[Ripiz]

I have win64, but it's compiled as 32bit code.

[Julio Jerez]

I do not have VS 2010 can you make the project with VS2008

Getting and setting 2010 spress that three tor four hours

[Ripiz]

I don't have VS2008.
Just include all .cpp and .h files, I think I have #pragma's for all libraries, you might need to specify directory for DirectX Includes/Libs, but that's all.

Edit:
Not sure about newton library, might need vs7 one, I think I use vs9, but it's 2.22 so I'm sure you have either of them, header is same anyways.

[Julio Jerez]

Can you make a exe that links to the newton dll? that is better and quiker for me to debug.
Making project file I usually have to spend a lot of time figure out path, and extenrla dependecies, d3d, and so on.

[Ripiz]

Compiled exe with dll: http://dl.dropbox.com/u/2637453/nwtn/exeCompiled.rar
Project with dll: http://dl.dropbox.com/u/2637453/nwtn/demoNew.rar

[Julio Jerez]

In you code if this is you ray cast, I believe it will never work because you are setting the parameter to 2.0 and I believe it should be 0.0

Code: Select all

float dist = 0;
float _cdecl Hit(const NewtonBody* body, const float* hitNormal, int collisionID, void* userData, float intersetParam){
   if(intersetParam < dist)
      dist = intersetParam;
   return intersetParam;
}
void SetUpCamera() {
   Matrix m_View, proj;
   m_TargetPos = loc;
   m_TargetPos.z += 50;
   m_EyePos.x = loc.x + 2000 * sin(yrot) * sin(xrot);
   m_EyePos.y = loc.y + 2000 * sin(yrot) * cos(xrot);
   m_EyePos.z = loc.z + 25 - 2000 * cos(yrot);
   dist = 2;
   NewtonWorldRayCast(world, m_TargetPos, m_EyePos, Hit, 0, 0);
   if(dist <= 1.0f)
      m_EyePos = m_TargetPos + (m_EyePos - m_TargetPos) * (dist - 0.05);
   Vector3 dir = m_EyePos - m_TargetPos;
   cameraAngle = atan2(dir.y, dir.x);
   D3DXMatrixLookAtLH(&m_View, &m_EyePos, &m_TargetPos, &m_UpVector);
   device->SetTransform(D3DTS_VIEW, &m_View);
}

If you change you to this

Code: Select all

//float dist = 0;
float _cdecl Hit(const NewtonBody* body, const float* hitNormal, int collisionID, void* userData, float intersetParam)
{
   float& dist = *((float*) usetData);
   if(intersetParam < dist)
      dist = intersetParam;
   return intersetParam;
}
void SetUpCamera() {
   Matrix m_View, proj;
   m_TargetPos = loc;
   m_TargetPos.z += 50;
   m_EyePos.x = loc.x + 2000 * sin(yrot) * sin(xrot);
   m_EyePos.y = loc.y + 2000 * sin(yrot) * cos(xrot);
   m_EyePos.z = loc.z + 25 - 2000 * cos(yrot);

   // this is the a bug
   //dist = 2;
   dist = 0.0f;
   // also make the ray go for begin point to end, no the other way around, make sure that in
   NewtonWorldRayCast(world, m_TargetPos, m_EyePos, Hit, 0, &dist);
   if(dist <= 1.0f)
      m_EyePos = m_TargetPos + (m_EyePos - m_TargetPos) * (dist - 0.05);
   Vector3 dir = m_EyePos - m_TargetPos;
   cameraAngle = atan2(dir.y, dir.x);
   D3DXMatrixLookAtLH(&m_View, &m_EyePos, &m_TargetPos, &m_UpVector);
   device->SetTransform(D3DTS_VIEW, &m_View);
}

It should work

[Ripiz]

Not only my camera + movement broke, but it still goes through terrain.
Setting it to 0.0f makes my code + Hit() think that RayCast hit something 0.0f away from Ray start

Edit:
Also it can't be it, as in Canyon this works fine.

[Julio Jerez]

you should set the last distance to 0.0 before each call to RayCast, if you do not then the next ray will fail

Do what I say and post the build the Ray cast should be perfect 100% of the time.