How to find associated voxel_coords for x.dense() 'NCHW'

[ammaryasirnaich]

Hi, would appreciate if i can get help on this thin about finding the associated voxel coordinate on the dense feature map. I am not sure if there is any API within the spconv for.

import spconv.pytorch as spconv
features = # your features with shape [N, num_channels]
indices = # your indices/coordinates with shape [N, ndim + 1], batch index must be put in indices[:, 0]
spatial_shape = # spatial shape of your sparse tensor, spatial_shape[i] is shape of indices[:, 1 + i].
batch_size = # batch size of your sparse tensor.
x = spconv.SparseConvTensor(features, indices, spatial_shape, batch_size)
x_dense_NCHW = x.dense() # convert sparse tensor to dense NCHW tensor.