align_view_to_cursor.py

"""
Align View to Cursor - Aligns the 3D viewport to the cursor's orientation.

This module provides functionality to orient the 3D viewport to match
the position and rotation of the 3D cursor, effectively letting the user
"look through" the cursor.
"""

import bpy
import mathutils


def align_view_to_cursor(context):
    """Align the 3D viewport to match the cursor's orientation.

    Calculates a view direction from the cursor rotation and repositions
    the viewport to look from the cursor's perspective.

    Args:
        context: Current Blender context
    """
    cursor_location = context.scene.cursor.location
    cursor_rotation = context.scene.cursor.rotation_euler

    # Calculate the view direction vector from cursor rotation
    view_direction = cursor_rotation.to_matrix() @ mathutils.Vector((0, 0, -1))
    view_location = cursor_location + view_direction

    # Build a view rotation matrix with Y-up orientation
    view_rotation = view_direction.to_track_quat('-Z', 'Y').to_matrix().to_4x4()
    view_rotation.translation = view_location

    # Apply to the first 3D viewport found on screen
    for area in context.screen.areas:
        if area.type == 'VIEW_3D':
            for region in area.regions:
                if region.type == 'WINDOW':
                    region_3d = area.spaces.active.region_3d
                    region_3d.view_matrix = view_rotation.inverted()
                    region_3d.view_location = view_location
                    bpy.ops.wm.redraw_timer(type='DRAW_WIN_SWAP', iterations=1)
                    break
            break


class VIEW3D_OT_align_view_to_cursor(bpy.types.Operator):
    """Align the 3D viewport to the cursor's position and orientation"""
    bl_idname = "view3d.align_view_to_cursor"
    bl_label = "Align View to Cursor"
    bl_description = "Orient the 3D viewport to look from the 3D cursor's perspective"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self, context):
        align_view_to_cursor(context)
        return {'FINISHED'}


# Registration
classes = (
    VIEW3D_OT_align_view_to_cursor,
)


def register():
    for cls in classes:
        bpy.utils.register_class(cls)


def unregister():
    for cls in reversed(classes):
        bpy.utils.unregister_class(cls)