Page 166 - Learn To Program With Scratch

(2) it is used in the CheckAnswer procedure to create the user’s feedback
message. When the Painter sprite finishes drawing, the NewQuestion pro-
cedure prompts the user for an answer with the say command.
When the Painter sprite receives the broadcast message, it draws the
corresponding triangle on the Stage. To make the game more exciting,
the Painter sprite uses random values for the triangle’s size, orientation,
and color, as shown in Figure 6-22.

Figure 6-22: Scripts for the Painter sprite

After asking the user to classify the drawn triangle, the main script uses
the wait until block (from the Control Palette) to pause until choice > 0
becomes true. The three button sprites will change choice when they are
clicked. The Scalene button sets choice to 1, the Isosceles button sets choice
to 2, and the Equilateral button sets choice to 3 (see Figure 6-23).

Script for the Scalene sprite Script for the Isosceles sprite Script for the Equilateral sprite
Figure 6-23: Scripts for the three button sprites

144 Chapter 6
www.it-ebooks.info