Jonathan Mack


About Me

United States of America


Recent Forum Posts

Scrubbinng the timeline with MMB May 22, 2018, 6:50 p.m.

I was going to say ‘switch cook mode to on mouse-up’ but that doesn't seem to apply to the playbar for some reason. I guess you are stuck typing the frame number for now.

how to wirte out velocity attribute to alembic? May 22, 2018, 6:46 p.m.

The alembic rop outputs all attributes by default. Unless you have specifically disabled the attribute, velocity should exist in the export.

Issues with point deforming multiple objects at once (hip file included) May 22, 2018, 1:19 p.m.

To avoid loops, one technique I use is to move the rest inputs apart in space, so each island shares no bind points. The point deform supports ‘deform only’ and ‘capture only’ modes that work in conjunction with this technique. Since capture data is only an array of indices and weights, translations have no affect on capture data.

To reduce the impact of float precision when there are a large number of islands, I encode the index (the island's identifier) as a cell position in 3-space.

a cell pattern can be computed from index as so:

int sx,sy,sz,i;
float x,y,z,pitch;
int numelem = number_of_elements(); // pseudocode, insert the relevant value/function here
i = @id; // use your identifier index here
pitch = spacing;  // space width of each cell
sx = stride_x;  // number of cells in x
sy = stride_y;  // number of cells in y
sz = sx * sy;

z = i / sz - numelem/sz/2;
y = (i % sz) / sx - sy/2;
x = (i % sz) % sx - sx/2;
@P += set(x,y,z)*pitch;