ZBrushCentral

inserting multiple negative meshes

ZBrush Usage Questions
#1

I cant get this to work… Ive been trying for ages, and the online instructions say “You can insert multiple meshes and add or subtract them all at once via a single remesh operation. You can even mix additive and negative meshes, creating different combinations at once.” but it dosent tell you how… sadly thats seems to be the case for much of the new instruction set, a considerable lack of detail.

So I can insert a negative mesh… lovely… but how do I insert several negative meshes, or more specifically duplicate the one Ive just inserted and rotate it, before I convert the whole thing back to a single mesh with the negative shapes cut out.

#2

Hi,
after you have drawn a mesh to insert while holding the ALT Key (to make it substract upon re-meshing) simply switch to Transpose/Move (w) and ctrl+alt click on the white ring in the middle one of the three rings on the transpose line. This will duplicate the just inserted mesh.

More info is on Page 36 of your ZB4R2_WhatsNew Document in the Documentation Folder of your Z4R2 Installation

#3

Hold ALT as you insert a mesh to make it negative.

To duplicate a negative mesh, go into transpose move mode, and hold down ctrl as you move it.

To duplicate a positive mesh as a negative mesh , hold down Ctrl+alt.

#4

Draw the first ‘negative’ mesh-insert while pressing the Alt key. Then enter Transpose move mode and while pressing the CTRL key, click on the middle ring of the transpose line and drag to create a copy. Repeating the same (i.e. ctrl click and drag) will enable you to create multiple copies.

#5

ooops, Spyndel is faster:)

#6

That’s what I call rapid response :slight_smile: 3 Answers in less than a minute.

#7

It’s Campi by a nose.

#8

yep… thats what Ive been doing, I added a mesh using the add sphere brush, while holding alt… then duplicated and rotated using transpose tools but look at the results…

the first shows the mesh with the negative elements in white… the second shows it when I hit add in the dynamesh pallet the second, identical result is what happens when I hit sub… the third inverted result is when I hit and…

none of them treat the mesh as a negative.

#9

Ohhh. I understand. Instead of hitting ADD/AND/SUb (which doesn’t do anything) try to remesh by dragging out with the CTRL Key in an open space of the canvas. The first drag will clear the mask, the second one will remesh and then it respects the negative meshes. I do not know why it does not work when clicking on the buttons. In fact the only way I get the Sub Button to work is when doubleclicking on it to substract Surface Noise (Page 56 ).

#10

And a second note … make sure that before you start inserting things that the DynaMesh Button is indeed active … When you insert things first (even negative meshes) and THEN click Dynamesh it will treat the negative meshes as “difference” – which is what you posted in your screenshots.

#11

not for me… same result as the second image down in the images above… should be the other way around…

while Im here, to ask a silly question. what do the “add, sub, and” buttons do then?

#12

ok just read your second response… thats the problem then.

but this is what I mean about a lack of detail in the online help section… most of what you have just told me isnt in it.

Ill go back and make my mesh again with the dyna mesh active from the start and see if it makes a difference.

#13

no Ive just done it again, the dynamesh button was indeed active from the start and the result is still treating the mesh as difference not negative… so same result.

#14

I can’t recreate your issue, unless I do as Campi mentioned, and draw the cylinder, and negative meshes before activating dynamesh for the first time.

Otherwise, all spheres remesh negatively as intended, using any remeshing method.

Start completely from scratch, new Cylinder PM3d, new spheres, everything. Somehow that cylinder is being treated as the negative mesh in your exercise. Perhaps that particular bit of geometry has become bugged somehow. It’s just not that difficult, I promise you.

#15

oky doke… I went back, from scratch, new cylinder, turned it into a polymesh, turned on dynamesh… followed all the above steps. result the same…

makes no difference if I use buttons or ctrl pen stroke in the unused area of the screen… the results are the same.

Ill turn off Zbrush and turn it back on again… but still its clearly a bug. like you say, its just not that hard, it should be working.

#16

ok tried that too… no good. nothing I do creates a negative sphere.

so clean load
new cylinder polymesh
new sphere inserts…

no joy

I went back and tried it with one sphere to make sure it wasnt during the duplication process that something went amiss… still no joy.

#17

Do exactly this:

  1. Restart Zbrush.

2)Select Sphere. Make Polymesh 3d

3)Turn on Dynamesh.

  1. Insert sphere using insert sphere brush, while holding alt.

  2. Hit Ctrl+Shift+A to clear mask, and then Ctrl -Drag in empty canvas (or simply Ctrl_drag twice…the first time will clear the mask, second will remesh)

If that doesn’t produce the intended result, you’re going to need to furnish System Info for Pixologic, and probably make an official ticket about it. Perhaps deleting a corrupted settings file somewhere will sort you, but I can’t advise you on that.

#18

Hmm. That’s weird. Just to be sure that we are on the same page, here’s a video:

http://www.campi3d.com/External/ZBC/Subtract.mp4

#19

that worked… I created a lovely little death star…

so I went back to the original problem, working with the cylinder.

one sphere on its own worked ok, using 4 drawn out using a radial effect on the brush didnt work for the first 4. however after duplicating it I had 3 rows as in the picture below, then the subtract function worked. but as soon as I tried to duplicate another pair and rotate the effect reverted to difference. see image below.

I need to submit a ticket I think.

#20

Yeah all right. I can reproduce it. You are rotating via Deformation not with Transpose right ?
As soon as you change the internal position (which is what deformation/preview does as opposed to transpose) than duplicate, than subtract goes wacky and does a difference. If I stick to transpose I can rotate and it will still work.

EDIT: Scratch that - it seems as soon as you duplicate any rotated object it doesn’t work. Definitely something with rotated things setting it off. Ok, I am out :slight_smile: