Start Your Engines - Scratch 2.0 Game Development - page 77

Engage thrusters
We will draw the collision mask in the Scratch Costumes editor. Let's see how to do so:
1. Click on the Folder icon in the Sprites menu to import the background image as a
sprite. We will use the original image as a base and paint over it.
2. Let's make sure that we are working in Vector Mode . We can toggle between
Vector Mode and Bitmap Mode in the lower-right corner of the Costumes tab.
3. Ensure that the image ills the enire stage. It should be the same size as the
Backdrop image. Use the Select tool to rescale the image, if necessary.
4. Choose a green color and select the Rectangle tool.
5. Draw green rectangles on top of all the grassy areas. Also include the blocked
borders surrounding the grass. Be as precise as possible.
6. Next, we switch over to a brown color.
7. Paint over all of the sandy areas. Don't worry about being too neat. Once the enire
sandy area is covered, we will push this layer to the back of the image with the Back
a layer buton. Hold Shift to send the layer all the way to the back with one click.
8. Lastly, choose a gray color and set the Pencil size to the biggest size.
9. In a fluid movement, follow the inner edge of the circuit.
10. Click on the Reshape tool to make the circular reshape widgets appear on the line
we just drew.
11. Move the widgets around to fit the line around the curves as neatly as possible.
12. You can add widgets to the line if you click on an empty place in the line.
13. Draw another curved line for the outer border of the road.
14. In case there are sill some gaps let in the middle, we will ill those up too.
15. When we're done with the drawing, we select the original background image
with the Select tool and press Delete to remove it. This will make our brown
background appear.