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In this add-on, you will program your game so users can only draw in the white spaces.
That way, users cannot draw outside the lines.
Select the pencil sprite.
Look at the code.
Right now, the pen is ready to draw when the mouse button is pressed down.
To avoid drawing outside the lines, the pen should only draw when the mouse is down AND
the sprite is inside the white space.
In the "if" portion of the "if-then" block, add an "and" block from the operators menu.
Add the "mouse down?" to one side of the “and” block.
One the other side, add a "touching color" block.
Click the color inside the block, then click the white drawing area.
Try it out.
It isn't working.
The pen still draws even when it is not touching the white space.
When the pen is touching the edges of the stage, it still draws.
In computer science, sometimes the first solution you try doesn't work, and that's okay.
If one idea doesn't work, keep trying until you find one that does.
Here's another potential solution.
Take out the "touching color" block, and put it back in the blocks palette.
The drawing end of the pencil is black, so see if you can get the pen to draw *only*
when the color black is touching the color white.
Add a "color is touching color" block from the sensing menu.
Click inside the first color area, and click the color black.
Then, click inside the second color area, and click the color white.
Try it out now!
Now the user can draw only in the white spaces.
Now it's your turn: Program the pencil sprite to draw if the mouse
button is pressed down AND the color black is touching the color white.