LN_draw_camera.py

from arm.logicnode.arm_nodes import *

class DrawCameraNode(ArmLogicTreeNode):
    """Renders the scene from the view of specified cameras and draws
    the render targets to the screen.

    @input Start: Evaluate the inputs and start drawing the camera render targets.
    @input Stop: Stops the rendering and drawing of the camera render targets.
    @input Camera: The camera from which to render.
    @input X/Y: Position where the camera's render target is drawn, in pixels from the top left corner.
    @input Width/Height: Size of the camera's render target in pixels.

    @output On Start: Activated after the `Start` input has been activated.
    @output On Stop: Activated after the `Stop` input has been activated.
    """
    bl_idname = 'LNDrawCameraNode'
    bl_label = 'Draw Camera'
    arm_section = 'draw'
    arm_version = 2
    min_inputs = 7

    num_choices: IntProperty(default=0, min=0)

    def __init__(self):
        super(DrawCameraNode, self).__init__()
        array_nodes[str(id(self))] = self

    def arm_init(self, context):
        self.add_input('ArmNodeSocketAction', 'Start')
        self.add_input('ArmNodeSocketAction', 'Stop')
        self.add_sockets()

        self.add_output('ArmNodeSocketAction', 'On Start')
        self.add_output('ArmNodeSocketAction', 'On Stop')

    def add_sockets(self):
        self.num_choices += 1
        self.add_input('ArmNodeSocketObject', 'Camera ' + str(self.num_choices))
        self.add_input('ArmIntSocket', 'X')
        self.add_input('ArmIntSocket', 'Y')
        self.add_input('ArmIntSocket', 'Width')
        self.add_input('ArmIntSocket', 'Height')

    def remove_sockets(self):
        if self.num_choices > 1:
            for _ in range(5):
                self.inputs.remove(self.inputs.values()[-1])
            self.num_choices -= 1

    def draw_buttons(self, context, layout):
        row = layout.row(align=True)

        op = row.operator('arm.node_call_func', text='Add Camera', icon='PLUS', emboss=True)
        op.node_index = str(id(self))
        op.callback_name = 'add_sockets'

        column = row.column(align=True)
        op = column.operator('arm.node_call_func', text='', icon='X', emboss=True)
        op.node_index = str(id(self))
        op.callback_name = 'remove_sockets'
        if len(self.inputs) == self.min_inputs:
            column.enabled = False

    def get_replacement_node(self, node_tree: bpy.types.NodeTree):
        if self.arm_version not in (0, 1):
            raise LookupError()
            
        return NodeReplacement.Identity(self)