The illustration of Sangsang transforming the cupboard into a pigeon cage can be drawn according to the following steps:

1. Determine the design:

First, Sangsang needs to determine Pigeon cage design. She can refer to existing pigeon cage styles or create her own design, determining the required dimensions, structure and details.

2. Draw a floor plan:

Sangsang can use paper and pencil to draw a floor plan of the pigeon cage. First, she needs to draw a top view, representing the upper and lower parts of the pigeon cage. Then, determine the size and position of each part according to the design, and draw the side and front views.

3. Add details:

Once the floor plan is complete, Sangsang can add details to make the drawing more vivid. For example, she can draw details such as doors for pigeons to enter and exit, nests, and feeders.

4. Coloring and shading:

Finally, Sangsang can choose to color the illustrations to increase the effect of the drawing. She can use colored pencils, watercolors, or computer drawing software to color, and add shading where appropriate to add dimension.

Expand knowledge:

1. Plan drawing:

Plan drawing is a two-dimensional figure used to represent the appearance and structure of an object. When drawing a floor plan, we need to draw the various parts of the object according to proportion and size, taking care to maintain accuracy and clarity.

2. Perspective drawing:

Perspective drawing is a drawing method used to represent three-dimensional objects, which can make the illustration more three-dimensional. In perspective drawing, we need to use perspective rules to draw the distance and proportion of objects.

3. Coloring and shading:

Coloring and shading are important means to add realism and three-dimensionality to illustrations. Through reasonable color selection and shading, the illustration can be made more vivid and layered.

4. Selection of drawing tools:

Drawing can be done using traditional paper-and-pencil drawing, or computer software can be used for digital drawing. Different tools have different characteristics and advantages, and Sangsang can choose a method that suits him for drawing.

To sum up, Sangsang’s illustration of transforming a cupboard into a pigeon cage can be completed by determining the design, drawing the floor plan, adding details, and coloring and shading. The drawing process requires care and patience, while perspective drawing and coloring techniques can be used to make the illustrations more vivid and three-dimensional.