Problem with GetCollisionPoint(). Help me !

[TrueLiar]

I'm using C# to write my app. I create a height map and want to pick triangles.
I create a selector
// Selector

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ITriangleSelector selector = scene.CreateTerrainTriangleSelector(terrain, 0);

Into render stuff, create intersector and triangle:

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Line3D line = new Line3D();
Vector3D vector = new Vector3D();
Vector3D intersection = new Vector3D();
Triangle3D triangle = new Triangle3D();

// create ray
line.start = cam.Position;
vector = (cam.Target - line.start).Normalize() * 100000.0f;
line.end.X = line.start.X + vector.X;
line.end.Y = line.start.Y + vector.Y;
line.end.Z = line.start.Z + vector.Z;

// Problem here
if(scene.SceneCollisionManager.GetCollisionPoint(line, selector, intersection, triangle))
{
  driver.SetTransform(TransformationState.WORLD, new Matrix4());
  driver.Draw3DTriangle(triangle, new Color(0,255,0,0));
}

When I move the camera lookat into heightmap, GetCollisionPoint() return true (correct). But intersection and triangle is value (0,0,0) and (0,0,0). So it donot draw a triangle then I expected. Any one help me !

[jerky]

Just test the triangle against one that has a value of (0,0,0)

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Triangle3D zeroTriangle = new Triangle3D(); 
if(scene.SceneCollisionManager.GetCollisionPoint(line, selector, intersection, triangle) && !triangle.Equals(zeroTriangle))
   { /*etc. */ }

The same problem exists in "normal c++" irrlicht.

[Spintz]

You can download Irrlicht-Spintz, link in my sig.

I have fixes for this, there are known bugs with collision, especially with DirectX, because of an FPU precision thing. You can apply individual fixes, by looking in the bug reports section, i think there's 3 total posts about different bugs that need to be applied.