Preview Render, Multi pass and MDD fails

strato · June 30, 2021

Having issues in later Versions to render previews. It asks for a null, than just creates an empty AVI in the Temp folder. Rendering a larger region with multipass in the choreography fails. Also the MDD export does not work. The MDD, OBJ and LWO files all have different point counts. Hooks create 2 points instead of merging to one, and with 4-point subdivision export 5 point patches will add 5 extra unmerged points. I tried it on different computers with Windows 7, but always the same issues. If someone had the same problem and a solution, I would love to hear about it. Thanks, Rolf

robcat2075 · July 1, 2021

19 hours ago, strato said:

Having issues in later Versions to render previews. It asks for a null,

Asks for a "null"?

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than just creates an empty AVI in the Temp folder.

I haven't used "Render Animation Preview" in decades. What do you use it for?

Something does seem wrong. However, if i RMB on the render window before I close it I can "Save Animation As" and get a real AVI file.

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Rendering a larger region with multipass in the choreography fails.

I was able to "Render Animation Preview" a large bounding box area (with multi-pass on (in the Options>rendering tab) and get a rendered result.

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Also the MDD export does not work. The MDD, OBJ and LWO files all have different point counts. Hooks create 2 points instead of merging to one, and with 4-point subdivision export 5 point patches will add 5 extra unmerged points. I tried it on different computers with Windows 7, but always the same issues. If someone had the same problem and a solution, I would love to hear about it. Thanks, Rolf

MDD I know nothing about

Does Gerald? @Fuchur

Fuchur · July 1, 2021

Hm, I am not an expert myself with MDDs, but I just tried to export a simple OBJ with MDD and imported it into Blender and that worked.
Could you provide a sample file where the problem is happening?

Best regards
*Fuchur*

PS: To import MDD in Blender you need to activate it first in the Preferences. (File >> User Preferences >> Add-ons >> Import-Export: NewTek MDD format (Enable the add-on))

Bobby · July 4, 2021

Try .mdd in A:M version 16RC.

strato · July 7, 2021

Thanks everybody for the responses. I am attaching a few pictures of my preview render issues. First I get the 'import null' request, than I get the unable to save message. V19 does create a temp file, but it just makes one empty AVI. V 13 creates a AM 12(?) Temp folder but at least renders out Targa files that can be saved. I will try with a 32bit V19 Version to see if it could solve the issue.

On the MDD side, short of sending my huge file, I created a test object 'Test Kettle' in V19 with 2 hooks and 4 5point patches. I than exported it in OBJ and LWO. MDD was created by Lightwave, so the chance that the count order stays correct is high in LWO. I than brought these files into C4D with a MDD plugin which applies the MDD as a deformer, it also gives me statistics of the object and the MDD file. The reason the MDD import failed has to do with the hooks and also with the OBJ exporter. If you open the Hash file in V19 or V13 the info will reveal 212 CPs. 2 CPs are for the hooks, so the 210 remaining need to be devided by 2 for the vertices it needs to create. So 105 plus 2, or 107 is the correct number. Unfortunately the OBJ exporter only merged one of the hooks to a single vertex and split the other one into two. So the OBJ file has 108 vertices. The MDD exporter decides to split both hooks and therefor has 109 Vertices, which is also wrong. The LWO file has 107 Vertices and is correct, but only the MDD/LWO export plugin from V13 ( part of a commercial plugin by Watanabe) correctly closes the polygons and produces the right count and order. However it will not work in a 64 bit program, so I hoped that V19 had the same functionality. As a question to Bobby: does your model have any hooks?