Adding nodes to existing material won't auto arrange the node editor

danielsian

Hi there, I'm adding nodes to an existing node material and I'm not being able to get a nice and organized result in the node editor, even after all connections are done.
However, if I create a material from scratch, then add the nodes and connect them the same way, the node editor finds an optimized way to organize the graph and the result is nice as expected.

So, these are the 2 approaches and the result:
1- add and connect nodes within an existing material - the new nodes are overlapping each other
2- create the material and then add and connect the nodes within it - the new nodes are nicely organized

How can I get a nice result with approach 1?

I used the example create_redshift_nodematerial_2024.py for the approach 2.
For the approach 1 I'm commenting the line:

createRSMaterial()

import c4d
import maxon

doc: c4d.documents.BaseDocument # The active document.

def createRSMaterial():
  
  urlTexRust: maxon.Url = maxon.Url(r"asset:///file_edb3eb584c0d905c")
  urlTexSketch: maxon.Url = maxon.Url(r"asset:///file_3b194acc5a745a2c")

  # The node asset IDs
  idTextureNode: maxon.Id = maxon.Id("com.redshift3d.redshift4c4d.nodes.core.texturesampler")
  idMixNode: maxon.Id = maxon.Id("com.redshift3d.redshift4c4d.nodes.core.rscolormix")
  idRsStandardMaterial: maxon.Id = maxon.Id("com.redshift3d.redshift4c4d.nodes.core.standardmaterial")

  # Instantiate a material, get its node material and the graph for the RS material space.
  material: c4d.BaseMaterial = c4d.BaseMaterial(c4d.Mmaterial)
  if not material:
    raise MemoryError(f"{material = }")

  nodeMaterial: c4d.NodeMaterial = material.GetNodeMaterialReference()
  graph: maxon.GraphModelRef = nodeMaterial.CreateDefaultGraph(
    maxon.Id("com.redshift3d.redshift4c4d.class.nodespace"))
  if graph.IsNullValue():
    raise RuntimeError("Could not add RS graph to material.")

  # Get the Standard Material node
  result: list[maxon.GraphNode] = []
  maxon.GraphModelHelper.FindNodesByAssetId(graph, idRsStandardMaterial, True, result)
  if len(result) < 1:
    raise RuntimeError("Could not find RS Standard node in material.")
  standardNode: maxon.GraphNode = result[0]

  with graph.BeginTransaction() as transaction:
    # Add two texture nodes and a blend node to the graph.
    rustTexNode: maxon.GraphNode = graph.AddChild(maxon.Id(), idTextureNode)
    sketchTexNode: maxon.GraphNode = graph.AddChild(maxon.Id(), idTextureNode)
    mixNode: maxon.GraphNode = graph.AddChild(maxon.Id(), idMixNode)

    mixAmount: maxon.GraphNode = mixNode.GetInputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.rscolormix.mixamount")
    mixAmount.SetDefaultValue(0.5)

    # Get the ports and set the values
    pathRustPort: maxon.GraphNode = rustTexNode.GetInputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.texturesampler.tex0").FindChild("path")
    pathSketchPort: maxon.GraphNode = sketchTexNode.GetInputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.texturesampler.tex0").FindChild("path")
    pathRustPort.SetDefaultValue(urlTexRust)
    pathSketchPort.SetDefaultValue(urlTexSketch)

    # Get the color output ports of the two texture nodes and the color blend node.
    rustTexColorOutPort: maxon.GraphNode = rustTexNode.GetOutputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.texturesampler.outcolor")
    sketchTexColorOutPort: maxon.GraphNode = sketchTexNode.GetOutputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.texturesampler.outcolor")
    mixColorOutPort: maxon.GraphNode = mixNode.GetOutputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.rscolormix.outcolor")

    # Get the ports
    mixInput1Port: maxon.GraphNode = mixNode.GetInputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.rscolormix.input1")
    mixInput2Port: maxon.GraphNode = mixNode.GetInputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.rscolormix.input2")
    stdBaseColorInPort: maxon.GraphNode = standardNode.GetInputs().FindChild(
      "com.redshift3d.redshift4c4d.nodes.core.standardmaterial.base_color")

    # Connect the nodes
    rustTexColorOutPort.Connect(mixInput1Port, modes=maxon.WIRE_MODE.NORMAL, reverse=False)
    sketchTexColorOutPort.Connect(mixInput2Port, modes=maxon.WIRE_MODE.NORMAL, reverse=False)
    mixColorOutPort.Connect(stdBaseColorInPort, modes=maxon.WIRE_MODE.NORMAL, reverse=False)

    transaction.Commit()

  doc.InsertMaterial(material)
  doc.SetActiveMaterial(material)
  c4d.EventAdd()

def main():
  # create a RS material
  createRSMaterial()

  # Get the material
  material = doc.GetActiveMaterial()

  # Check if the material exists and is a node material
  if not material or not material.IsInstanceOf(c4d.Mmaterial):
    return

  # Get the node material
  nodeMaterial = material.GetNodeMaterialReference()

  nodespaceId = c4d.GetActiveNodeSpaceId()

  rsNodeSpaceId = maxon.Id("com.redshift3d.redshift4c4d.class.nodespace")

  if nodespaceId != rsNodeSpaceId:
    return

  # Get the graph
  try: graph = nodeMaterial.GetGraph(nodespaceId)
  except: return

  # Set the asset IDs
  idTextureNode = maxon.Id("com.redshift3d.redshift4c4d.nodes.core.texturesampler")
  idColorCorrection = maxon.Id("com.redshift3d.redshift4c4d.nodes.core.rscolorcorrection")


  # Find all the texture nodes
  tex_nodes = []
  maxon.GraphModelHelper.FindNodesByAssetId(graph, idTextureNode, True, tex_nodes)

  if not tex_nodes:
    return

  for node in tex_nodes:
    for out_port in node.GetOutputs().GetChildren():
      for dest_port, wires in out_port.GetConnections(maxon.PORT_DIR.OUTPUT, None, maxon.Wires.All(), maxon.WIRE_MODE.ALL):
        with graph.BeginTransaction() as transaction:
          # Remove existing connection
          maxon.GraphModelHelper.RemoveConnection(out_port, dest_port)

          # Create node
          colorCorrectionNode = graph.AddChild(maxon.Id(), idColorCorrection)

          # Get the ports
          cc_inPort = colorCorrectionNode.GetInputs().FindChild("com.redshift3d.redshift4c4d.nodes.core.rscolorcorrection.input")
          cc_outPort = colorCorrectionNode.GetOutputs().FindChild("com.redshift3d.redshift4c4d.nodes.core.rscolorcorrection.outcolor")

          # Connect the nodes
          cc_outPort.Connect(dest_port, modes=maxon.WIRE_MODE.NORMAL, reverse=False)
          out_port.Connect(cc_inPort, modes=maxon.WIRE_MODE.NORMAL, reverse=False)
          transaction.Commit()

  doc.InsertMaterial(material)
  c4d.EventAdd()

  
if __name__ == "__main__":
  main()

Dunhou

Hi @danielsian ,
As @m_adam said, this is the "auto-layouter" didn't work, if we add something to existed materials, the new node will set at the center of the graph editor, seems nothing we can do here, one bad solution is call the "Arrange All Nodes", but this will break the existed layout, hope it will be a better solution asap.

Cheers~
DunHou

danielsian

Thanks @Dunhou, I appreciate your reply confirms what seems to be a bug, and I wonder if @m_adam could confirm it based on the working code I provided, which demonstrates the issue in a simple way.

m_adam

Hi thanks a lot, this is most likely the same bug that @Dunhou reported but that I was never able to reproduce.
I will forward that to the responsible dev.

Cheers,
Maxime.

danielsian

Thanks @m_adam !

danielsian

Hey guys, how is it going with this BUG?
Is it gonna be fixed soon?
Thanks

m_adam

Hi sadly no news, except we kind of know the issue, sadly this issue is somehow by design and will require an architectural change.

While we still want to fix this issue, everything is about priority and this is not a urgent priority at the moment so I can't tell you when it will be fixed. But it's on our list.
Cheers,
Maxime.