Oh, you've edited your previous message! Thanks! I will try it.

@m_adam thanks for your prompt response. I'm looking forward to hearing from you.

Thank you very much for all your detailed explanation, @ferdinand!

Thank you for @Dunhou answer. It was ultimately completed in JSON format

Hi @Neekoe, That's great to hear you've managed to solve the issue! For your future postings please note that according to our Support Procedures: We cannot debug your code for you and instead provide answers to specific problems. This effectively means that you're welcome to ask your questions and attach the code snippet that demonstrates your question or issue you're struggling with. However, we cannot debug your entire codebase, so you have to isolate your specific question and the corresponding part of code yourself before asking the question. Cheers, Ilia

Thanks for helping out @spedler!

Thanks @Neekoe to have shared your solution and thanks @Dunhou for helping. When you pass LV_TREE the Draw method is not called to have it called you need to pass either LV_USERTREE or LV_USER. Cheers, Maxime.

@ferdinand Thank you so much. He perfectly solved all my problems

@freeze I wrote this a few years back which might give you a good starting point. https://plugins4d.com/Product/FunRay https://github.com/kentbarber/rtow4d Cheers, Kent

@ferdinand Thank you for replying!

Hi @kimberlyhtown, Welcome to the Maxon developers forum and its community, it is great to have you with us! Getting Started Before creating your next postings, we would recommend making yourself accustomed with our forum and support procedures. You did not do anything wrong, we point all new users to these rules. Forum Overview: Provides a broad overview of the fundamental structure and rules of this forum, such as the purpose of the different sub-forums or the fact that we will ban users who engage in hate speech or harassment. Support Procedures: Provides a more in detail overview of how we provide technical support for APIs here. This topic will tell you how to ask good questions and limits of our technical support. Forum Features: Provides an overview of the technical features of this forum, such as Markdown markup or file uploads. It is strongly recommended to read the first two topics carefully, especially the section Support Procedures: Asking Questions. About your First Question I suppose you're asking about the Attribute Manager history, which one can access by using the following arrows: [image: 1738944299742-bf4e829b-8ae1-4eae-a86b-c8dbc57c713d-image.png] Unfortunately, no. the Attribute Manager is a quite complex part of C4D (e.g. with multiple AM having each their own history), hence it is not transparently exposed to our public SDK and one's typically limited by the functionality listed in our C++ SDK the AOM part: Active Object Manager. Cheers, Ilia

@ferdinand Thank you for answering ,I 'll try it.

Thanks for your response. We found the issue. Turns out we had to delay load our dlls for earlier versions of the plugin R21 etc

Hello everyone, we have moved this topic to a mail discussion, when there are outcomes relevant for other developers, I will post them here. Cheers, Ferdinand

@ferdinand Thank you very much! The problem is solved and now I know the way of MODATA_CLONE used.

Hello @uogygiuol, Thank you for the added details. Yes, reducing the complexity of questions is the right thing to do, thank you for doing tit. Essays are counterproductive, as we then tend to overlook things (q.e.d., I overlooked the fact that you wanted to mangle the scene file in this thread). In general, trying to mangle a file beforehand is not a good route, as you always risk invalidating the file. For your very specific scenario - very simple scene graph, just geometry, no materials, animations or other dependencies - it could make sense. I briefly talked with the owner of our GLTF-importer, and we do not do any sanity checking, e.g., comparing nodes with meshes. So, you could just 'clean up' the scene graph ("nodes") of the file, and Cinema's GLTF importer will then just ignore extra data in fields such as "meshes". How fruitful this will be, you will have to find out yourself. I already had the hunch that your are here surfing on the edge of what is sensbible, and GLTF JSON files which translate to gigabytes of memory are certainly an edge case, due to the fact that text-based file formats are usually a bad choice for such heavy data. Using Python to Read JSON My guesstimate would be that when you throw a GLTF JSON file at Python's JSON parser - which takes five minutes to load in Cinema 4D - to mangle it, you end up with a net-loss or tie, because you loose most or more than the won time in that Python JSON stage. Python's json module is mostly written in C to make it performant, but that is still a lot of JSON to deserialize, modify, and then serialize. One idea could be to use re, i.e., regular expressions, to find the "nodes" section in that file, just deserialize that from JSON, modify it, serialize back to a JSON string, and write it back in place, and by that sidestep having to deserialize that whole file. The problem with all that is that json.load allows you to pass a file object, allowing you to bypass the Python VM entirely and let the data reside in C until the parsing is done, while re does not allow you to regex a file object directly (AFAIK), you always must read the file object into lines or chunks to then pass these strings to the re module. I.e., you would have to load that whole file into a Python string first. What would come here out on top, I have no clue, but my hunch is that re might loose, as Python's string handling is not the fastest. Alternatives might be 3rd party libs such as isjon (a lazy JSON loader) but I do not know how performant it is. For this section it would make a huge difference if you could predict the position of "nodes" in the file, either exactly as a chunk offset, or in the form of 'I know that it is always very close to the end, so let's regex parse the file in reverse'. Using a Binary File Format But the fact remains that text-format file types, e.g., JSON GLTF, become extemely ineffcient once you pass the ~100 MB barrier. Using something like binary GLTF or another binary format such as FBX will likely speed up your Cinema 4D loading times quite a bit, no extra steps required. And to be clear, text-based file formats are always wildely ineffcient. It is just that below the ~100 MB barrier (adjust for the beefiness of your machine), you can drown that inefficency with pure computing power and have the nice advantage of a human-readble file format. Cheers, Ferdinand

That is perfect, thank you for being through and concise, lifesaver.

Hi @derudo, Welcome to the Maxon developers forum and its community, it is great to have you with us! Getting Started Before creating your next postings, we would recommend making yourself accustomed with our forum and support procedures. You did not do anything wrong, we point all new users to these rules. Forum Overview: Provides a broad overview of the fundamental structure and rules of this forum, such as the purpose of the different sub-forums or the fact that we will ban users who engage in hate speech or harassment. Support Procedures: Provides a more in detail overview of how we provide technical support for APIs here. This topic will tell you how to ask good questions and limits of our technical support. Forum Features: Provides an overview of the technical features of this forum, such as Markdown markup or file uploads. It is strongly recommended to read the first two topics carefully, especially the section Support Procedures: Asking Questions. About your First Question There's no single known "thing" we're aware of that could lead to such behavior. In other words, it can be lots of different "things" that caused the symptoms you're describing. Hence, without any further details everything I'm pointing out here is highly speculative. I also don't think answering the question "What could have happened?" is by any means productive, so let's switch the point of view to "How one could diagnose it?". Since you haven't posted any console output in your question, I assume you haven't checked that. This would actually be the first thing to check. Please refer to our Python Console Manual and searching on the forum. Next, try to figure out if it's only UI that stopped appearing or your plugin isn't registered at all anymore. You can do this by checking (e.g. with some temporary print statements) if you plugin is actually functional. On the screenshot you've posted the structure is kind of strange, but we're not sure if it's just a visualization matter of your software. Namely, the plugin.pyp file is expected to reside in the root of the plugin folder. Essentially, the following hierarchy level is not supposed to be there: [image: 1737450594273-232c47cd-171e-4642-8c12-7661b51e6ce5-image.png] Please refer to the article Plugin Structure Manual: Directory Structure and double check your plugin in this regard. If the points above don't lead to any result, try debugging it step-by-step. Namely, strip out everything except the essentials (like plugin registration) and continue adding things piece-by-piece until it starts failing. By the way, one can easily achieve this by using any version control system (e.g. git), as they typically provide a lossless way to manage your code (i.e. remove and add parts of code, without being worried to lose any of them). This approach could also have prevented your scenario in first place, when something stopped working and there're no clues about the change that has lead to it. If this still doesn't help, you can share your plugin here (or send us via contact form, when confidential information is involved). However, I must warn you that our Support Procedures still fully apply, namely: We cannot debug your code for you and instead provide answers to specific problems. Cheers, Ilia

Hello @myosis, Welcome to the Maxon developers forum and its community, it is great to have you with us! Getting Started Before creating your next postings, we would recommend making yourself accustomed with our forum and support procedures. You did not do anything wrong, we point all new users to these rules. Forum Overview: Provides a broad overview of the fundamental structure and rules of this forum, such as the purpose of the different sub-forums or the fact that we will ban users who engage in hate speech or harassment. Support Procedures: Provides a more in detail overview of how we provide technical support for APIs here. This topic will tell you how to ask good questions and limits of our technical support. Forum Features: Provides an overview of the technical features of this forum, such as Markdown markup or file uploads. It is strongly recommended to read the first two topics carefully, especially the section Support Procedures: Asking Questions. About your First Question All the methods you list simply do not exist (neither in C++ nor in Python), see c4d.utils.Neighbor for the type overview. I therefore must assume that you are using an AI, like, for example, ChatGPT, which hallucinated these methods. Please note that we reserve the right to refuse support when confronted with undisclosed AI gibberish, especially for beginner content. Always state when you used an AI to generate code. Something such as an edge does not exist concretely in our API and many other APIs, i.e., other than for points and polygons, there is no explicit data type for edges which would be stored. Edges are defined implicitly by CPolygon. To filter a selection for edges of a certain length, you would have to convert edge indices to polygon and point indices and then measure the distance between the relevant points. Cheers, Ferdinand Result [image: 1737027755224-074e2ada-a9ce-45b4-800a-acf7e060941a-image-resized.png] Code """Deselects all edges in the edge selection of the active object whose edge length exceeds MAX_EDGE_LENGTH. Must be run as a Script Manager script with an editable polygon object selected. """ import c4d doc: c4d.documents.BaseDocument # The currently active document. op: c4d.BaseObject | None # The primary selected object in `doc`. Can be `None`. MAX_EDGE_LENGTH: float = 25.0 # The maximum length of an edge before to be considered too long. MAX_EDGE_LENGTH_SQUARED: float = MAX_EDGE_LENGTH ** 2 # The square of `MAX_EDGE_LENGTH`. def main() -> None: """Called by Cinema 4D when the script is being executed. """ if not op or not op.IsInstanceOf(c4d.Opolygon): raise ValueError("The selected object is not a polygon object.") # Get the edge selection of the object and turn it into a list of selected edges indices. Also, # get the points and polygons of the object. selection: c4d.BaseSelect = op.GetEdgeS() selectedEdges: list[int] = [i for i in range(op.GetEdgeCount()) if selection.IsSelected(i)] points: list[c4d.Vector] = op.GetAllPoints() polygons: list[c4d.CPolygon] = op.GetAllPolygons() def getPointByIndex(poly: c4d.CPolygon, index: int) -> c4d.Vector: """Returns the point of the polygon at the given index. CPolygon has no index access, so we fix that here. """ if index == 0: return points[poly.a] elif index == 1: return points[poly.b] elif index == 2: return points[poly.c] elif index == 3: return points[poly.d] # Iterate over the edges and find the one's that are longer than MAX_EDGE_LENGTH. An edge index # is defined as: # # "The edges are indexed by 4 * polygon + edge where polygon is the polygon index and edge is # the edge index between 0 and 3." # # So, we must revert that here, then measure the edge length, and collect all too long edges. tooLongEdges: list[int] = [] for edgeIndex in selectedEdges: polygonIndex: int = edgeIndex // 4 edgeInPolygonIndex: int = edgeIndex % 4 poly: c4d.CPolygon = polygons[polygonIndex] pointA: c4d.Vector = getPointByIndex(poly, edgeInPolygonIndex) pointB: c4d.Vector = getPointByIndex(poly, (edgeInPolygonIndex + 1) % 4) # Getting the length of a vector is quite expensive, so we compare the squared lengths. edgeLengthSq: float = (pointA - pointB).GetLengthSquared() if edgeLengthSq > MAX_EDGE_LENGTH_SQUARED: tooLongEdges.append(edgeIndex) # Print the indices of the edges that are too long. print("The following edges are too long:", tooLongEdges) # Deselect all edges in the object's edge selection that are too long. for edgeIndex in tooLongEdges: selection.Deselect(edgeIndex) # Push an update event to Cinema 4D to redraw the object. c4d.EventAdd() if __name__ == '__main__': main()

@i_mazlov I get it, thanks for your reply.