Creating Stories and Games with Scratch - Adventures in Raspberry Pi - page 63

FIGURE 3-24 Health-point-stealing flower sprite script
Don't forget to add the script to hide the lower sprite after the Adventurer sprite
enters the cave. After you have added this script, you can duplicate the lower
to cover the stage with more obstacles, making the game more interesting.
To duplicate the lower sprite, right-click on it in the Sprites palette and click
Duplicate. You can do this as many times as you like to make multiple copies.
Improving the Movement of the
Adventurer Sprite Using “if” Blocks
he player controls the Adventurer sprite by using the keys on the keyboard. his
works well when the sprite is on the stage using the Outside background, as there are
no walls. However, when it enters the cave, the sprite will appear to be walking over
the walls. You can use another if condition to help stop this from happening.
1. Click the Adventurer sprite and locate the four scripts that control movement
using the arrow keys on the keyboard (refer to Figure 3-17).
2. On one of the scripts, add a control block if inside the forever if loop, above
the point in direction 90 block that is already there.
3. Add the sensing block touching color into the blank hexagon on the if loop
you have just added. Select the colour of the walls by clicking the coloured square
box; this action will turn the mouse cursor icon into a droplet icon, and you can
select the walls with your mouse, getting the exact colour match required.
4. Next, add the motion block move 0 steps inside the if loop and set the value
to -20 steps. Figure 3-25 shows the new script.
5. Add the same extra piece of script to the three remaining control scripts for each
key. Don't forget to save the ile and test that your script works.