retaining colour during fracture

[angels_arrows]

Hi, I have been experimenting on Voronoi fracture sop. I have created the set up and fracture seems to be working, but the colour attribute from the original object does not get transfered onto the rbd object and also during the shatter.

Thanks in Adavance !

rock_shatter_.hipnc.zip

[johner]

You've got "Visualize Impact Region" turned on on the Fracture Solver, which applies a point color to the geometry to help visualize the fracture radius. Turning that off should maintain the color.

[angels_arrows]

Hi Jhoner, I have tried turning off the " visualize impact " but still no difference . I am new to fracture sop but somehow the the colour attrib does not get read into the fracture node

[johner]

Hi Jhoner, I have tried turning off the " visualize impact " but still no difference . I am new to fracture sop but somehow the the colour attrib does not get read into the fracture node

Hmm, that's odd, the Fracture Solver shouldn't affect the color in any way unless that option is on. You didn't include your geometry file in the example, so I just substituted a sphere. With "Visualize Impact" off, I see a yellow sphere that fractures and stays yellow. What are you seeing?

[angels_arrows]

hey thanks for the quick response, sorry for being a bit vague . I ran into the problem when i tried applying texture and displacement map on the stone object. Just as a geometry it renders fine with the texture and displacement, but when i make it into rbd and apply fracture the textures suddenly vanish showing only a grey stone object. Here is the hip file with the colour map and displace map.

stone.zip

[johner]

hey thanks for the quick response, sorry for being a bit vague . I ran into the problem when i tried applying texture and displacement map on the stone object. Just as a geometry it renders fine with the texture and displacement, but when i make it into rbd and apply fracture the textures suddenly vanish showing only a grey stone object. Here is the hip file with the colour map and displace map.

I believe your problem is that you're rendering the DOP Network directly, rather than DOPImport-ing the geometry back into the "stone" Geometry object for rendering. You need to add a DOPImport SOP, set to import rbdobject4* to get the original object and all its pieces. Then on that Geometry object you can set various rendering properties, add velocity motion blur, etc.

Attached is a render of frame 15 and the .hip file using a DOPImport node. (I also turned off True Displacements on your materials, since you have adjacent displaced and non-displaced primitives, which can lead to tearing - and temporarily switched to a stock HDR map for the environment light)

BTW, the workflow (and speed, functionality, etc.) in dynamic fracturing is very much improved in H11, with shelf tools and such that set all this up for you.

stone_shatter_dopimport.hipnc

[angels_arrows]

Wow ! thats a big help !! I haven still switched to H11 wil do it soon... for now on a still frame it looks pretty much how I want it .. .. Thanks a ton !!

[angels_arrows]

hi jhoner , I was wondering if there is anyway to get into the sop level of the object that cuts the rock. I want to texture the inner pieces to make it more realistic. Is there a way to put uv or apply diff texture to inner walls of cut pieces .

[ikarus]

the fracture outputs an Outside and Inside group just apply uv coordinates/material to the inside group, as far as i know

[angels_arrows]

the fracture outputs an Outside and Inside group just apply uv coordinates/material to the inside group, as far as i know

if I try adding material there it switches to the new material on impact and does not retain my original texture layer. Is there any other way or am I doing something wrong ?

[johner]

if I try adding material there it switches to the new material on impact and does not retain my original texture layer. Is there any other way or am I doing something wrong ?

The bad news is that there's not really a good way to do it with the setup you're using (i.e. in H10). The good news is you can do it easily in H11, and if you're doing dynamic fracturing you really should upgrade, or at least download the Apprentice version to try it out.

The problem, as you've seen, in that some primitives in the "inside" group end up in the "outside" group the next time they are fractured, since strictly speaking they are on the outside of the piece being re-fractured. The workaround in H11 is to add a primitive attribute called "exterior" or something, and set it to 1 on all the primitives, default 0, before you do any dynamic fracturing. Then any newly created, interior primitives will have the default "exterior" value of 0, and you can assign materials, colors, whatever to all interior primitives with an exterior value of 0, no matter how many times you re-fracture. In the example below I use the shorthand "@exterior==0" group expression, but you could explicitly create a primitive group if you wanted.

Unfortunately the original Fracture OTL uses a different method of creating the interior surfaces that causes them to inherit all the same attribute values from its surrounding primitives, so all the primitives would show up as exterior in H10.

I took your stone object into H11 and just used the "Make Breakable" shelf tool in H11 to drop it on the ground and fracture it twice, tweaked a couple of fracture settings, and then used the above setup to set all the interior primitives to a red color. You could add your explosion metaball, just make sure to enable "Fracture From Magnet Force Metaballs" on the VoronoiFractureConfigureObject.

Edit: I should add, sometime it's also helpful to add a PrimitiveSplit SOP set to split on the "exterior" attribute, after your DOPImport node, if you want to get sharp edges between your original surface and the interior surfaces.

stone_drop_h11.hipnc

Edited July 29, 2010 by johner

[angels_arrows]

Thanks for the extensive breakdown on the problem .. I do have a HD version of H10 need to upgrade to H11 ..