keymesh.py

import bpy
import re

bl_info = {
    "name": "Keymesh Alpha",
    "author": "Pablo Dobarro (Developer), Daniel Martinez Lara (Animation and Testing), Aldrin Mathew (Shortcut, Undo)",
    "version": (0, 1, 2),
    "blender": (2, 91, 0),
    "location": "Sidebar > KeyMesh",
    "warning": "Experimental",
    "category": "Object",
    "description": "This addon helps in improving your Stop Motion animation workflow. Use Ctrl Shift A for faster workflows.",
    "doc_url": "https://vimeo.com/506765863",
    # "doc_url": "https://www.youtube.com/watch?v=vlNsvL30TmE&feature=youtu.be",
}


def next_available_keymesh_object_id():
    max_id = 0
    for ob in bpy.data.objects:
        if ob.get("km_id") is None:
            continue
        object_keymesh_id = ob["km_id"]
        if object_keymesh_id > max_id:
            max_id = object_keymesh_id
    return max_id + 1


def object_next_available_keyframe_index(ob):
    if ob.get("km_id") is None:
        return 0

    object_keymesh_id = ob["km_id"]

    max_index = 0
    # object_name_full = ob.name_full
    for mesh in bpy.data.meshes:
        if mesh.get("km_id") is None:
            continue
        mesh_km_id = mesh["km_id"]
        mesh_km_datablock = mesh["km_datablock"]

        if mesh_km_id != object_keymesh_id:
            continue

        keyframe_index = mesh_km_datablock
        if keyframe_index > max_index:
            max_index = keyframe_index
    return max_index + 1


def keymesh_insert_keyframe_ex(object, keymesh_frame_index):
    if object.get("km_id") is None:
        object["km_id"] = next_available_keymesh_object_id()
    object_keymesh_id = object["km_id"]

    bpy.ops.ed.undo_push()
    new_mesh = bpy.data.meshes.new_from_object(object)
    ob_name_full = object.name_full
    new_mesh_name = ob_name_full + "_km" + str(keymesh_frame_index)
    new_mesh.name = new_mesh_name
    new_mesh["km_id"] = object_keymesh_id
    new_mesh["km_datablock"] = keymesh_frame_index
    object.data = new_mesh
    object.data.use_fake_user = True
    current_frame = bpy.context.scene.frame_current
    object["km_datablock"] = keymesh_frame_index
    object.keyframe_insert(data_path='["km_datablock"]', frame=current_frame)


def keymesh_insert_keyframe(object):
    new_keyframe_index = object_next_available_keyframe_index(object)
    keymesh_insert_keyframe_ex(object, new_keyframe_index)

    fcurves = object.animation_data.action.fcurves
    for fcurve in fcurves:
        if fcurve.data_path != '["km_datablock"]':
            continue
        for kf in fcurve.keyframe_points:
            kf.interpolation = "CONSTANT"

    bpy.app.handlers.frame_change_post.clear()
    bpy.app.handlers.frame_change_post.append(updateKeymesh)


class KeyframeMesh(bpy.types.Operator):
    """Adds a Keyframe to the mesh, after which you can edit the mesh to keep the changes."""

    bl_idname = "object.keyframe_mesh"
    bl_label = "Keyframe Mesh"
    bl_options = {'REGISTER', 'UNDO'}

    @classmethod
    def poll(cls, context):
        return context.active_object is not None

    def execute(self, context):
        ob = context.active_object
        keymesh_insert_keyframe(ob)
        return {"FINISHED"}


def updateKeymesh(scene):
    for object in scene.objects:
        if object.get("km_datablock") is None:
            continue

        object_km_id = object["km_id"]
        object_km_datablock = object["km_datablock"]

        final_mesh = None
        for mesh in bpy.data.meshes:

            # No Keymesh Datablock
            if mesh.get("km_id") is None:
                continue
            mesh_km_id = mesh["km_id"]
            mesh_km_datablock = mesh["km_datablock"]

            # No keymesh datat for this object
            if mesh_km_id != object_km_id:
                continue

            # No keymesh data for this frame
            if mesh_km_datablock != object_km_datablock:
                continue

            final_mesh = mesh

        if not final_mesh:
            continue

        object.data = final_mesh


class PurgeKeymeshData(bpy.types.Operator):
    """Delete all unused Keymesh Data"""

    bl_idname = "object.purge_keymesh_data"
    bl_label = "Purge Keymesh Data"
    bl_options = {'REGISTER', 'UNDO'}

    @classmethod
    def poll(cls, context):
        return True

    def execute(self, context):
        used_km_mesh = {}

        for ob in bpy.data.objects:
            if ob.get("km_id") is None:
                continue

            km_id = ob.get("km_id")
            used_km_mesh[km_id] = []

            fcurves = ob.animation_data.action.fcurves
            for fcurve in fcurves:
                if fcurve.data_path != '["km_datablock"]':
                    continue

                keyframePoints = fcurve.keyframe_points
                for keyframe in keyframePoints:
                    used_km_mesh[km_id].append(keyframe.co.y)

        delete_mesh = []

        for mesh in bpy.data.meshes:
            if mesh.get("km_id") is None:
                continue

            mesh_km_id = mesh.get("km_id")

            if mesh_km_id not in used_km_mesh:
                delete_mesh.append(mesh)
                continue

            mesh_km_datablock = mesh.get("km_datablock")

            if mesh_km_datablock not in used_km_mesh[mesh_km_id]:
                delete_mesh.append(mesh)
                continue

        print("purged")
        for mesh in delete_mesh:
            print(mesh.name)
            mesh.use_fake_user = False

        updateKeymesh(bpy.context.scene)

        for mesh in delete_mesh:
            if mesh.users == 0:
                bpy.data.meshes.remove(mesh)

        return {"FINISHED"}


class KeymeshPanel(bpy.types.Panel):
    bl_idname = "panel.keymesh_panel"
    bl_label = "Keymesh v0.1.2 Alpha"
    bl_category = "Keymesh"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"

    def draw(self, context):

        column = self.layout.column()
        column.scale_y = 1.5
        column.label(text="Add Keyframe (Ctrl Shift A)")
        column.operator("object.keyframe_mesh", text="Keyframe Mesh")
        self.layout.label(text="Delete all unused Keymesh Data")
        self.layout.operator("object.purge_keymesh_data", text="Purge Keymesh Data")


addon_keymaps = []


def register():
    bpy.utils.register_class(KeyframeMesh)
    bpy.utils.register_class(PurgeKeymeshData)
    bpy.utils.register_class(KeymeshPanel)
    bpy.app.handlers.frame_change_pre.clear()
    bpy.app.handlers.frame_change_pre.append(updateKeymesh)
    windowManager = bpy.context.window_manager
    keyConfig = windowManager.keyconfigs.addon
    if keyConfig:
        keyMapView = keyConfig.keymaps.new(name="3D View", space_type="VIEW_3D")
        keyMapItem = keyMapView.keymap_items.new(
            "object.keyframe_mesh", type="A", value="PRESS", shift=True, ctrl=True
        )
        addon_keymaps.append((keyMapView, keyMapItem))


def unregister():
    for keyMapView, keyMapItem in addon_keymaps:
        keyMapView.keymap_items.remove(keyMapItem)
    addon_keymaps.clear()

    bpy.utils.unregister_class(KeyframeMesh)
    bpy.utils.unregister_class(PurgeKeymeshData)
    bpy.utils.unregister_class(KeymeshPanel)
    bpy.app.handlers.frame_change_pre.clear()


##if __name__ == "__main__":
##    register()