This describes some aspects of Piper animated movie.
I’m interestend in this rock topology. How to model this topology ?
Dude.
They pushed the limits of rendering capabilities to achieve phenomenal results, part of which includes handling scenes that contain over five billion polygons worth of grains of sand, and you’re curious as to how they modeled a simple rock. That’s all you’re curious about? Nothing else? Not even interested in the rest of the animated short judging by the brevity of the OP?
If you want to know how the rock is made, the topology is basically an Ico-Sphere with subdivisions and sculpting to carve in the finer details. Not too complex, could be made in under 5 minutes or so.
Also, this thread should probably belong in Blender and CG Discussions for the technical aspects of how the movie is made, or Support / Modeling if you’re just here for the rock.
I wonder how much memory it took to render those millions of instances, you will still run far short on memory in many cases simply because of the sheer number (info like position still needs to be stored per-object).
Very impressive tech, but anyone hoping to render stuff like this without faking it in Blender (that assuming you can even run it on home hardware) will be waiting a very long time (barring any development surprises).
Hehe. Yes. This is how I roll. 
I saw the their tech presentation before for their other movie. Thanks
Looks to me like they use a method of subdividing a very simple mesh (As omnilord stated) and displacing it. Here’s an example i made in blender (Similar method to what the rock generator add-on does really)
Left is the base shape, right is the same shape with modifiers
Not exactly the same topology as the image you posted, but similar at least, try experimenting with different base shapes and see what produces the closest results 
Heres an example using the rock generator add-on -
No chance of instancing the amount they did though, that was an incredible display of geometry instancing.
5 billion polygons is just a staggering amount of data
edit: and p.s - they aren’t rocks, they are some of the grains of sand! 
the “rock gen” works iffy ok , there are just a few types and then just variations on a theme
for low poly meshes it is good at it’s job
now a HI poly mesh something like this 540 MiB mesh “small body” ( TNO )
– 6 images –
http://imgbox.com/fUrSEYv9
or this large bit of space rock 3 million vertexes
– 3 images –
http://imgbox.com/IS6eiEI3
i use a simple cylindrical displacement map and a very subdivided ico sphere
or use each pixel as a vertex in the mesh
– the mola/pds DEM importer
They’re okay for little sand particles though (the detail in Pixar’s grains is actually not that complex).
Even then, it’s unlikely you’ll even need tiny details unless you had particles only millimeters away from the camera.
– double post -----