I've been using MOI 2.0 for more than two years now and It is an incredile easy tools to use.
I've been waiting to get the exported STEP models in color to works, but it never happened.
I've just tried to used the 3.0 version to see if issues was solved, but it is still there.
What is so complex about this issue?

Hi Fran, STEP format is a bit tricky with colors, there are 2 different sub variations of STEP format, and the sort of main original structure (AP203) just does not have any mechanism in it for representing colors.

So that's not a particularly unusual thing for colors to just not come through with STEP format in general.

There is a different variation called AP214 I think which then adds things like colors, I think MoI will read in one of those but won't generate one of those for export currently.

I'll check with the author of the STEP library that MoI uses and see if it can be configured to write out AP214 or whether that's not supported currently.

I'm not sure if writing AP214 by default might cause other problems though since it seems that often times the original AP203 structure seems to be considered the normal one used for mechanical CAD data transfer.

Anyway that's why it's a somewhat tricky issue, because the main original STEP format itself just did not include any method in it to store color data.

- Michael

I can export from MoI to STEP and import into Acrobat Extended and colour is there.
The exception is that each object can have only one colour per solid, my work around
has been to separate the solid before export.

So it looks like the colour info is in the Step file MoI exports, it's whether the other
importing programs read it or not.

Hi Michael, from my experience with other CAD packages there are usually the two options when exporting STEP;
STEP 203 = .stp
STEP 214 = .step

I've hardly needed the use for 214 as we were told it was mainly used for the automotive sector which I'm not in and 203 works just fine, I think people want colours for MoI because styles = layers where in traditional MCAD the layers, object colour and object name are separate.

Anyhow it seems an upcoming AP 242 is set to replace both AP 203 and AP 214.

-

Hi Danny,

> STEP 203 = .stp
> STEP 214 = .step

Hmmm, that's interesting - I've never really noticed that myself... I've always treated either .stp or .step as interchangable just indicating it's a STEP file and not necessarily the specific sub type, similar to .jpg/.jpeg or .igs/.iges .

- Michael

Hi Michael,

> I've always treated either .stp or .step as interchangable just indicating
> it's a STEP file and not necessarily the specific sub type, similar to .jpg/.jpeg or .igs/.iges .

I thought so too until I couldn't see a STEP file when opening in NX with the extension .step, I had to change it to AP 214 in the file type drop down list for me to see it and open.

-

Hi Danny, do you know of anything other than NX that does it that way? A quick survey of a couple of programs here all have .stp/.step under the same file type in the drop down list.

- Michael

Hi Michael,

I only have access to NX and Solidworks, however searching the net reveals NX is the only one that separates the file formats out, see the images below of the open dialog drop down list for, NX, Solidworks, Solid Edge and Catia.

BTW the STEP extensions I first listed for AP 203 and AP 214 are the other way around.....I think.

NX


Solidworks


Solid edge


Catia


-

Geomagic design, (formerly Alibre), shows separate exports for step 203 and 214.

- Brian

Oh! Then it's NX and Geomagic, thanks Brian for the chip in :)

Cheers

Hi Brian,

> Geomagic design, (formerly Alibre), shows separate exports for step 203 and 214.

Does it say that one of them is .stp (3 character file extension) and the other one is .step with a 4 character file extension?

Or does it say something like *.stp;*.step for both types?

- Michael

They both have the same extension.
STEP AD 203 file (*.stp) (It saves as size 8KB)
STEP AD 214 file (*.stp) (It saves as size 5KB)

- Brian

Remember there is something like 28 ap's for the step format.

I don't think that the extension denotes any of these. It is just an application preference.

Upon import, you usually find a selection of (step,stp) to "see" both file type extensions. Some apps give you 2 exports just to be able to "write" the extension of choice, but it would be no different than renaming the extension yourself.

I think it's up to the particular translator to solve the contents of the file.

Hi Fran, some more info on color in STEP files:

> I've been waiting to get the exported STEP models in color to works, but it never happened.
> I've just tried to used the 3.0 version to see if issues was solved, but it is still there.
> What is so complex about this issue?

So I've looked into this a bit more today, and there is a way with the STEP AP203 variant (which MoI exports) to have surface colors assigned, and MoI does write those out currently. If you open up your STEP file in a text editor you'll see them as COLOUR_RGB() entries in the file.

But it appears that only some programs will read this type of color information. Other programs (including MoI's own importer) will only read colors if they are present as layer assignments rather than just direct individual object color properties.

I guess it's really the layer definitions that are the main thing added in for AP214.

What program are you importing the STEP file into?

- Michael

Ok, so I got some more info.

The whole thing is a little complex.

The original STEP AP203 "edition 1" did not define colors at all. AP214 added color support. Then after that AP203 "edition 2" also added in colors to AP203.

MoI will write an AP203 file with colors in it, but some programs may only expect to see AP203 "edition 1" files, and may only try to read color info from AP214 files. This seems to vary quite a bit between programs.

In the future it should be possible to make MoI have an option for writing AP214 type files, but it's something that is currently under development in the I/O library that MoI uses, so that won't happen until MoI v4 probably.


So anyway the summary is: MoI does write color info currently to STEP files, but due to some of the history of the STEP file format some programs may not read it in from the particular type of file that MoI currently writes.


- Michael

Hi Michael,
I'm using a PCB CAD program called Altium Designer AD14.
I'm actually a electronic engineer, but I use MOI to create simple 3D parts body for electronics components.
I will take a look between a STEP files that provides the proper color info and one that doesn't.

From what I see, all my color model are in AP214 file format.

- BR, Francis

Hi Francis, the author of the STEP library that MoI uses says that he wants to support exporting type AP214 in the future, so if Altium Designer will only read in colors from STEP 214 that may help. I'm not sure exactly when that will happen in MoI, probably sometime during the v4 timeframe.

- Michael

Hi Michael,
Just wanted to touch base on the AP214 STEP export. I've been waiting for more than 3 years to see it happens in MOI, bought an upgrade to v3 and it seems that it wasn't patched within all that water passing under the bridge :(
Is there any plan to support it in an upcoming release?

Hi all,
Very surprising, the file "Step" with colors work fine for me.
I work with Moi V3 on tablet.
I export "Step" to "AnsysSpaceclaim" or "Inventor" on desktop computer and no problem of colors.
Best regards,
Nicolas.

Hi Francis, I do hope to look into it for v4. I've been undergoing a major rewrite since v3 to make MoI 64-bit and have a Mac native build and so there has been a longer than usual gap between releases this time and it has taken priority over working on things like this, sorry.

MoI does currently write color information into STEP files, just without announcing it specifically as an AP214 type file. Many programs do find the color information in there so I guess that's why I haven't heard about this more frequently from too many people. If your program would just use the colors if they were available instead of only if it was AP214 then it would probably work.

It might take some detailed back and forth testing with you to see what it takes to get colors into Altium Designer since I don't have it over here. Please ask me about it again once v4 betas are underway.

- Michael