In the visualization of the "floor-tile" domain, each element of the problem is represented using specific geometric shapes, colors, and positions to convey its status and role clearly. Here's the breakdown:

1. **Tiles**: 
   - **Shape**: Rectangles represent individual tiles on the grid.
   - **Size**: All tiles are of uniform size to depict the grid structure clearly.
   - **Color**: 
     - Green indicates a "clear" tile, meaning it is neither painted nor occupied.
     - Blue indicates an "occupied" tile, meaning a robot is currently on it.
     - Red (if used) would indicate a "painted" tile, meaning it has been painted and cannot be occupied.
   - **Position**: Tiles are positioned in a grid layout, with each tile's position corresponding to its coordinates (e.g., tile_0-1 is at the top-left corner).

2. **Robots**:
   - **Shape**: Circles represent robots, distinguishing them from the rectangular tiles.
   - **Size**: Smaller than tiles to fit within a tile and indicate that they occupy that tile.
   - **Color**: 
     - White for a robot holding the white color.
     - Black for a robot holding the black color.
   - **Position**: Positioned on the tile they occupy with text indicating their identifier and current color.

3. **Available Colors**:
   - **Shape**: Small rectangles represent the available colors.
   - **Size**: Smaller than a tile to indicate they are resources rather than grid elements.
   - **Position**: Placed outside the grid to signify availability for switching.

4. **Legend**:
   - Provides a mapping of colors to their meanings, ensuring the diagram is self-explanatory.
   - Positioned away from the main grid to avoid overlap and maintain clarity.

5. **Text**:
   - Labels for tiles and robots are included within their respective shapes to identify them and their status.
   - Contrast between text and background is maximized for readability.

Overall, this encoding utilizes geometric and color distinctions to convey the state and roles of each object in the problem, ensuring clarity and ease of understanding for the viewer.