correcting ray_splits, reversing

cpp/open3d/t/geometry/RaycastingScene.cpp

@@ -872,10 +872,10 @@ RaycastingScene::ListIntersections(const core::Tensor& rays,
     shape.push_back(num_rays + 1);
     result["ray_splits"] = core::Tensor(shape, core::UInt32);
     uint32_t* ptr = result["ray_splits"].GetDataPtr<uint32_t>();
-    ptr[0] = 0;
-    for (int i = 1; i < cumsum.size() + 1; ++i) {
-        ptr[i] = cumsum[i - 1];
+    for (int i = 0; i < cumsum.size(); ++i) {
+        ptr[i] = cumsum[i];
     }
+    ptr[num_rays] = num_intersections;
     shape[0] = intersections_vector.sum();
     result["ray_ids"] = core::Tensor(shape, core::UInt32);
     result["geometry_ids"] = core::Tensor(shape, core::UInt32);

cpp/open3d/t/geometry/RaycastingScene.h

@@ -105,13 +105,11 @@ class RaycastingScene {
                                     const int nthreads = 0);
 
     /// \brief Computes the closest points on the surfaces of the scene.
-    /// \param rays A tensor with >=2 dims, shape {.., 6}, and Dtype Float32
-    /// describing the rays.
-    /// {..} can be any number of dimensions, e.g., to organize rays for
-    /// creating an image the shape can be {height, width, 6};
-    /// The last dimension must be 6 and has the format [ox, oy, oz, dx, dy, dz]
-    /// with [ox,oy,oz] as the origin and [dx,dy,dz] as the direction. It is not
-    /// necessary to normalize the direction.
+    /// \param query_points A tensor with >=2 dims, shape {.., 3} and Dtype
+    /// Float32 describing the query points. {..} can be any number of
+    /// dimensions, e.g., to organize the query_point to create a 3D grid the
+    /// shape can be {depth, height, width, 3}. The last dimension must be 3 and
+    /// has the format [x, y, z].
     /// \param nthreads The number of threads to use. Set to 0 for automatic.
     /// \return The returned dictionary contains:
     ///         - \b points A tensor with the closest surface points. The shape