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Some experimentation was required

Because I didn't know the diameter of the beachball, I had to experiment to determine how far to move it to the left of the origin to locate it at the leftside of the Stage as shown in Image 4 . I settled on a value of -200 for the x coordinate and a value of 0 for the y coordinate.

Positioning the other beachball

In the interest of brevity, I won't show the code required to position the beachball on the right side of the Stage. I did exactly the same thing for that beachballexcept that I specified the value of the x coordinate to be 200 instead of - 200. This causes the beachball named RightBeachball to move to the right side of the Stage when the user clicks the green flag.

The basketball

Initializing the position of the basketball

Image 7 shows a portion of the rightmost panel after clicking on the sprite named Basketball . (Note the image of the basketball in the upper right corner. When this is an image of the basketball, all of the scripts in the rightmost panel apply to thebasketball sprite.)

Image 7. initializing the position and orientation of the basketball.

Missing image.
Image 7. Initializing the position and orientation of the basketball.

You will note that the tan block and the uppermost blue block in Image 7 arethe same as in Image 6 except that the x coordinate value is set to 0. This causes the basketball to move to the origin when the user clicks the greenflag.

Initializing the orientation of the basketball

However, Image 7 contains a block that is not contained in Image 6 . The bottom blue block in Image 7 is used to set the orientation of the basketball. (By orientation, I mean the direction that the basketball is facing.)

It may seem strange to say that a round basketball is facing in one direction or the other. However, every sprite has a front, back, top, and bottomeven in those cases where it is not visually obvious. The orientation would be visually obvious if I were to use an animal for the sprite in place ofthe basketball. You can tell which direction the basketball is facing by observing the curved diagonal lines on the basketball.

After you drag the blue block labeled point in direction into the rightmost panel, you can click the arrow in the white box to expose the followingfour choices:

  • (90) right
  • (-90) left
  • (0) up
  • (180) down

As you can see, I selected the choice that causes the basketball to face to the right. As a result, when the user clicks the green flag, the basketballwill move to the origin and turn to face the right.

Handling mouse events on the basketball

Image 8 shows all of the code in the rightmost panel that applies to the basketball.

Image 8. all of the code that applies to the basketball.

Missing image.
Image 8. All of the code that applies to the basketball.

The top script in Image 8 is another copy of the script that was shown in Image 7 . At this point, we are interested in the behavior of the bottom script in Image 8 .

Behavior of the bottom script

The dark tan block labeled when this sprite clicked specifies that all of the actions produced by the blocks attached to that block will occur when the userclicks the basketball with the mouse. Furthermore, those actions will occur in top-to-bottom order.

Questions & Answers

what is biology
Hajah Reply
the study of living organisms and their interactions with one another and their environments
AI-Robot
what is biology
Victoria Reply
HOW CAN MAN ORGAN FUNCTION
Alfred Reply
the diagram of the digestive system
Assiatu Reply
allimentary cannel
Ogenrwot
How does twins formed
William Reply
They formed in two ways first when one sperm and one egg are splited by mitosis or two sperm and two eggs join together
Oluwatobi
what is genetics
Josephine Reply
Genetics is the study of heredity
Misack
how does twins formed?
Misack
What is manual
Hassan Reply
discuss biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles
Joseph Reply
what is biology
Yousuf Reply
the study of living organisms and their interactions with one another and their environment.
Wine
discuss the biological phenomenon and provide pieces of evidence to show that it was responsible for the formation of eukaryotic organelles in an essay form
Joseph Reply
what is the blood cells
Shaker Reply
list any five characteristics of the blood cells
Shaker
lack electricity and its more savely than electronic microscope because its naturally by using of light
Abdullahi Reply
advantage of electronic microscope is easily and clearly while disadvantage is dangerous because its electronic. advantage of light microscope is savely and naturally by sun while disadvantage is not easily,means its not sharp and not clear
Abdullahi
cell theory state that every organisms composed of one or more cell,cell is the basic unit of life
Abdullahi
is like gone fail us
DENG
cells is the basic structure and functions of all living things
Ramadan
What is classification
ISCONT Reply
is organisms that are similar into groups called tara
Yamosa
in what situation (s) would be the use of a scanning electron microscope be ideal and why?
Kenna Reply
A scanning electron microscope (SEM) is ideal for situations requiring high-resolution imaging of surfaces. It is commonly used in materials science, biology, and geology to examine the topography and composition of samples at a nanoscale level. SEM is particularly useful for studying fine details,
Hilary
cell is the building block of life.
Condoleezza Reply
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Source:  OpenStax, Teaching beginners to code. OpenStax CNX. May 27, 2013 Download for free at http://cnx.org/content/col11498/1.20
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