Scratch Paint Activity Pack
What will you need?
The Scratch website. It is free to use and works on all devices.
What will you learn?
Program Microsoft Paint-style software in Scratch using:
– Mouse inputs or touch screen inputs to use pen blocks to draw on the screen. The program will sense whether the mouse or finger is touching the screen and then use selection to put the pen down or up.
– Selection and sensing again to hide the pencil when it goes over a menu, to make it easier for the user to choose menu items.
– Broadcasts to send messages from a menu item (e.g a colour) to the pencil sprite to change the colour of the pen and the costume (different pencil colour). Use this also to change the pencil thickness.
1. Pencil and Drawing (Inputs, loops, selection and sensing)
Watch the video to learn how to add a pencil sprite and program it to draw with mouse inputs. (If you are using a trackpad it may not work as well).
Tip
To clear drawings while testing click to tap the erase all code block in the pen extension blocks.
2. Cursor Hiding and Revealing (Selection and sensing)
Watch the video to learn how to add sensing commands so that the cursor hides when it goes onto the menu and shows when it goes back to the white drawing area.
3. Colours (Broadcasts)
Watch the video to learn how to add a colour palette sprite that when it is clicked, it broadcasts a message to change the costume of the pencil sprite and also the colour of the brush strokes it leaves. Once you have got one colour working, duplicate the sprites and costumes to add more colours.
(The video is 4 minutes long so it may help to pause it and then try the skill)
4. Brush size
Watch the video to learn how to add brush size sprites to your menu so that when the sprites are clicked they change the size of the brush of drawing sprite. The video demonstrates how to do one brush size so once you have done one, could you have different lines for different thicknesses?
Challenge 1: Clear Drawings
Add a clear drawings sprite by either using an X or even drawing a rubbish bin sprite, then use the ‘Erase all’ in the pen section so that when it is clicked it clears the screen of drawings.
Challenge 2: Eraser
Can you add an eraser sprite (either drawing one or saving the image from here and uploading that), then use it to broadcast a message to your pencil sprite that when the eraser sprite is clicked, it draws with a white brush?