In the visualization of the parking domain, each object is represented with specific shapes and colors to convey its status and position clearly:

1. **Shapes**:
   - **Rectangles**: Represent curbs. The size of each rectangle is uniform to indicate that all curbs have the same capacity.
   - **Circles**: Represent cars. The size of the circles is consistent to signify that all cars are of the same size.

2. **Colors**:
   - **Green**: Indicates a "clear" status. For curbs, this means the curb is empty and available for parking. For cars, it means the car is free to move (no car is double parked behind it).
   - **Red**: Denotes a "blocked" status. For curbs, this means the curb is occupied. For cars, it indicates that the car is double parked or has another car behind it, preventing it from moving.
   - **Text Colors**: Chosen for high contrast against the background of the shape to ensure readability.

3. **Legend**:
   - A legend is included to map colors to their meanings (e.g., green for clear and red for blocked). This helps users quickly understand the status of each object without needing to interpret textual labels.

4. **Text Labels**:
   - Each object, whether a curb or a car, has a text label inside it. This label includes the identifier and status (e.g., "car6\nblocked"). The text is positioned to avoid overlap and maintain clarity.

5. **Layout**:
   - Curbs are laid out in a horizontal grid to represent their sequential order. Cars are placed inside or behind curbs to show their parking status. The layout ensures no two objects overlap, maintaining a clear and organized diagram.

This encoding allows anyone viewing the diagram to quickly ascertain the status and relationships of cars and curbs within the parking domain, regardless of their familiarity with the specific instance being visualized.