The 造型面板 (「背景面板」 in the 舞台) is part of Scratch's built-in 绘图编辑器. The pane consists of all the 「造型」 of the currently selected sprite. It is scrollable and highlights blue the costume that is currently being displayed on the 绘图编辑器 canvas.
Without the costume pane, there would be no possible way without hacking to access the different 「造型」 of a particular sprite. It is a necessary feature to Scratch. It also displays the 角色编号 value of each individual costume in a sprite. By showing the 角色编号, one can relate what 「造型」 are needed when programming in accordance with the 角色编号 block.
The pane also provides, at the very top, four buttons for creating a new costume. Without these options, creating a new costume would be a more difficult process involving duplication or the 背包.
The 「造型」 are placed vertically in the costume pane. One can scroll down or up if there are too many 「造型」 to all be displayed simultaneously. The layout consists of the 缩图 of each costume along with a few properties. Underneath the costume thumbnail is the costume name and 解析度. In the top-left of the thumbnail is a small digit representing the costume's 角色编号 value.
If a costume is selected, it will have a blue box around it. Then, the costume will be displayed on in the 绘图编辑器 for editing. At the top-right of the blue box is a small "x"; when clicked, the current costume will be deleted. Any costume accidentally deleted can always be undone with 编辑 > 复原.
At the very top of the costume pane are the four options for creating a new costume. They do not scroll but have a fixed position to always be easily accessed wherever the vertical scrolling position is.