I am creating a Python script that bakes the textures for each object in the scene, and then deletes all the shader nodes of the materials of each object and replaces them with image texture nodes of the baked diffuse and roughness maps. However, I've noticed that, after running the program, all of the image texture nodes have been replaced with the baked maps of only the last object and the baked maps of the other objects have vanished.

This is the code that creates the images that get baked onto

def bakeObj(obj, dest, img_size):
    obj.select_set(True)
    bpy.context.view_layer.objects.active = obj 

    imgDiffuse = bpy.data.images.new(obj.name + '_Diffuse',img_size,img_size) 
    imgRough = bpy.data.images.new(obj.name + '_Rough',img_size,img_size) 

In between I bake the textures of the object onto imgDiffuse and imgRough. Then this is the code for the assignment of the images.

for mat in obj.data.materials:
    print(mat.name)
    mat.use_nodes = True
    nodes = mat.node_tree.nodes
    
    # delete nodes 
    for n in mat.node_tree.nodes: 
        excludedNodes = {'Principled BSDF','Material Output'}
        if n.name not in excludedNodes:
            mat.node_tree.nodes.remove(n)


    diffuse_node = nodes.new('ShaderNodeTexImage')
    diffuse_node.name = 'Diffuse_node'
    diffuse_node.image = imgDiffuse
    
    rough_node = nodes.new('ShaderNodeTexImage')
    rough_node.name = 'Rough_node'
    rough_node.image = imgRough
    
    # stick baked texture in material
    principled_bsdf_node = mat.node_tree.nodes["Principled BSDF"]
    links = mat.node_tree.links
    links.new(principled_bsdf_node.inputs[0], diffuse_node.outputs[0])
    links.new(principled_bsdf_node.inputs[9], rough_node.outputs[0])

For a more detailed illustration of the issue, see the images below. This is the setup of the objects. The highlighted material "shader_crustacean" should have been assigned the texture files corresponding to its parent object "crustacean(1, 1).parts(0, factory=LobsterBodyFactory)"

Instead, it has the texture files corresponding to the last object "crustacean(1,1).parts(10).extra(BezierCurve.015, 10)". The same occurs for all other materials.

Meanwhile, the image dropdown menu seems to show that all the other files have actually disappeared or were overwritten somehow.

It seems that the last call of the function somehow causes all the other textures to get destroyed. Is this some kind of memory overwriting issue or weird bug with blender? For reference, this is all being run in headless mode.

I am creating a Python script that bakes the textures for each object in the scene, and then deletes all the shader nodes of the materials of each object and replaces them with image texture nodes of the baked diffuse and roughness maps. However, I've noticed that, after running the program, all of the image texture nodes have been replaced with the baked maps of only the last object and the baked maps of the other objects have vanished.

This is the code that creates the images that get baked onto

def bakeObj(obj, dest, img_size):
    obj.select_set(True)
    bpy.context.view_layer.objects.active = obj 

    imgDiffuse = bpy.data.images.new(obj.name + '_Diffuse',img_size,img_size) 
    imgRough = bpy.data.images.new(obj.name + '_Rough',img_size,img_size) 

In between I bake the textures of the object onto imgDiffuse and imgRough. Then this is the code for the assignment of the images in the same function.

for mat in obj.data.materials:
    print(mat.name)
    mat.use_nodes = True
    nodes = mat.node_tree.nodes
    
    # delete nodes 
    for n in mat.node_tree.nodes: 
        excludedNodes = {'Principled BSDF','Material Output'}
        if n.name not in excludedNodes:
            mat.node_tree.nodes.remove(n)


    diffuse_node = nodes.new('ShaderNodeTexImage')
    diffuse_node.name = 'Diffuse_node'
    diffuse_node.image = imgDiffuse
    
    rough_node = nodes.new('ShaderNodeTexImage')
    rough_node.name = 'Rough_node'
    rough_node.image = imgRough
    
    # stick baked texture in material
    principled_bsdf_node = mat.node_tree.nodes["Principled BSDF"]
    links = mat.node_tree.links
    links.new(principled_bsdf_node.inputs[0], diffuse_node.outputs[0])
    links.new(principled_bsdf_node.inputs[9], rough_node.outputs[0])

This entire function is called once per object via a loop. For a more detailed illustration of the issue, see the images below. This is the setup of the objects. The highlighted material "shader_crustacean" should have been assigned the texture files corresponding to its parent object "crustacean(1, 1).parts(0, factory=LobsterBodyFactory)"

Instead, it has the texture files corresponding to the last object "crustacean(1,1).parts(10).extra(BezierCurve.015, 10)". The same occurs for all other materials.

Meanwhile, the image dropdown menu seems to show that all the other files have actually disappeared or were overwritten somehow.

It seems that the last call of the function somehow causes all the other textures to get destroyed. Is this some kind of memory overwriting issue or weird bug with blender? For reference, this is all being run in headless mode.