scripts/camera_pose.py

"""
the blender script to export camera pose to TUM format
"""

import bpy

def write_some_data(context, filepath, use_some_setting):
    print("running write_some_data...")
    camera = context.active_object
    mw = camera.matrix_world
    scene = context.scene
    frame = scene.frame_start

    f = open(filepath, 'w', encoding='utf-8')
    
    # Write the header line
    f.write("# TUM format ground truth pose, timestamp x y z q_x q_y q_z q_w\n")
    
    while frame <= scene.frame_end:
        scene.frame_set(frame)
        x, y, z = mw.to_translation()
        q = mw.to_quaternion()
        f.write("%04d %f %f %f %f %f %f %f\n" % (frame, x, y, z, q.x, q.y, q.z, q.w))
        frame += 1
    f.close()

    return {'FINISHED'}


# ExportHelper is a helper class, defines filename and
# invoke() function which calls the file selector.
from bpy_extras.io_utils import ExportHelper
from bpy.props import StringProperty, BoolProperty, EnumProperty
from bpy.types import Operator


class ExportSomeData(Operator, ExportHelper):
    """This appears in the tooltip of the operator and in the generated docs"""
    bl_idname = "export_test.some_data"  # important since its how bpy.ops.import_test.some_data is constructed
    bl_label = "Export Some Data"

    # ExportHelper mixin class uses this
    filename_ext = ".txt"

    filter_glob: StringProperty(
        default="*.txt",
        options={'HIDDEN'},
        maxlen=255,  # Max internal buffer length, longer would be clamped.
    )

    # List of operator properties, the attributes will be assigned
    # to the class instance from the operator settings before calling.
    use_setting: BoolProperty(
        name="Example Boolean",
        description="Example Tooltip",
        default=True,
    )

    type: EnumProperty(
        name="Example Enum",
        description="Choose between two items",
        items=(
            ('OPT_A', "First Option", "Description one"),
            ('OPT_B', "Second Option", "Description two"),
        ),
        default='OPT_A',
    )

    def execute(self, context):
        return write_some_data(context, self.filepath, self.use_setting)


# Only needed if you want to add into a dynamic menu
def menu_func_export(self, context):
    self.layout.operator(ExportSomeData.bl_idname, text="Text Export Operator")


# Register and add to the "file selector" menu (required to use F3 search "Text Export Operator" for quick access).
def register():
    bpy.utils.register_class(ExportSomeData)
    bpy.types.TOPBAR_MT_file_export.append(menu_func_export)


def unregister():
    bpy.utils.unregister_class(ExportSomeData)
    bpy.types.TOPBAR_MT_file_export.remove(menu_func_export)


if __name__ == "__main__":
    register()

    # test call
    bpy.ops.export_test.some_data('INVOKE_DEFAULT')