According to the documentation we should be able to bind the tiles of a reserved resource to more than one heap but I haven't found a way to achieve this.

"with the one key difference that D3D12 allows a reserved resource to have tiles from multiple heaps"

https://docs.microsoft.com/en-us/windows/desktop/api/d3d12/nf-d3d12-id3d12commandqueue-updatetilemappings

UpdateTileMappings only accept one heap as parameter and calling it multiple times with a different heap override the whole mapping with the last call unless I screwed up somewhere else?

Can someone explain it in greater detail than this documentation?

3 hours ago, ChuckNovice said:

calling it multiple times with a different heap override the whole mapping with the last call

That's unexpected. Calling it multiple times should only apply the subset of mappings specified in each call.

2 minutes ago, SoldierOfLight said:

That's unexpected. Calling it multiple times should only apply the subset of mappings specified in each call.

So the right way actually is to call UpdateTileMappings multiple times?

Thanks, I will concentrate my efforts on figuring out what went wrong when I tried it.

I got it to work. Turn out I was simply sampling from the wrong array slice of my texture array.

I got one more question regarding this. I'm unable to visualize reserved resources with PIX. They don't seem to be supported yet.

How do you guys debug yours? I would've expected to be able to see my reserved resource as specified by the tile mapping.

Use the send-a-frown button, that gets back to the PIX guys, and they might be able to point you to something you're missing. I would've expected that to be supported, but it's possible it's not. Either way, you should let them know.