Display the butterfly at 50-percent opacity

Listing 5 calls the setOpacity and drawPictureOnPicture methods

• to set the opacity of the butterfly
• and draw it onto the display with 50-percent opacity
• when it first appears on the screen.

The image of the butterfly is centered on the background

• as shown in Figure 1.

    butterfly = setOpacity(butterfly,50);
    drawPictureOnPicture(
                  butterfly,
                  display,
                  backgroundWidth/2 - butterflyWidth/2,
                  backgroundHeight/2 - butterflyHeight/2);
    display.show();