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Hello and welcome to this little shop in this little show.

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We will be moving the ball.

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This is what the ball looks like at the moment.

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We have got the x and y coordinates hard coded with these values.

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What we will do to change the position of the ball we are going to create two variables for the x and

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y that we'll use to replace these hard coded values.

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The variables that we will create for the x and y y coordinates will be used to define the position

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at which the ball is drawn at.

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All right let's quit the variable.

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What I like to do is I want t to start.

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Want the want the board game to start from the bottom centre part of the comforts so when I defined

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the variable each will reflect starting from the bottom centre part of the compass so to create the

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variable type in the one var and then give the x the value of the name on the variable we'll call it

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X and will give it a value off of the canvass variable dot

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with

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Divide by two.

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So this will be the value for the X ordinate way replacing this hard coded value here where is variable.

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That will create another variable for the Y which is B R and then we give the value

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canvas

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dot height

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minus 30.

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So these variables we make the movement of the ball pronounced the more meant you can't tell that the

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circle is been painted on the canvas every 10 milliseconds.

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By declaring these variables we can see some activity on the ball moving.

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Note that every time the ball is painted on the screen is referred to as a frame so each page tin instance

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is a frame.

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We'll need to add a small value to the X and Y variable so that after every frame is painted on the

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canvas or is drawn under cover it will appear that the ball is moving.

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So to do this we need to define variable to variables extra variables that will represent these movements.

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So let's create the variables here as well.

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So we'll define the first one variable D takes and give it a value of.

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To.

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Next quit variable d y and give it a value of minus 2.

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K What we need to do will need to update this drol function so that every time frame in New frame is

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painted it updates the X and Y variable.

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What that means that on every frame the X and Y variable will be updated with the D X and D Y variable

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on every frame.

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So what they'll do.

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It will make it will make it appear that the ball is painted in a new position on every object.

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So let's update this function.

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The first time will need to do is change is hard coded value and replace that with.

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The eggs variable.

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Hand or Y variable.

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I'm going to change the radius from 20 to 10 and then the rest will say live the refs the same.

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This value here the force option is optional so we can skip that remove that.

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I am going to remove that because it is optional.

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Finally we need to represent the D X and d d y values so we'll put that just have the bottom before

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we close the before this close and curly braces.

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So what do we do.

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X the value of x plus EPOS to do X and Y loss equates to the Y.

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All right saw that on every frame.

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The x variable will be updated with this and the Y would be updated with that.

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So save this.

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All right so let me refresh this so you can see it appears.

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Let me refresh that again.

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You can see that the movement may refresh consider a moment all right.

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What it does it looks appears as if the board is moving bot leaving a trail behind it.

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That's why it looks likes on fire.

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Run this again and see the ball move in.

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It appears it's leaving a tree behind it.

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The reason it appears that leaving a trail is because each time frame is painted for the new circle

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or new born.

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It does not remove the previous one so it has them all together and with continuous trail.

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So in the next leg election we can all learn how to clear a compass before each frame.

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That way you can see the ball.

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They define the moment they collect in the frames and not clearing up after each other is form a continuous

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trail.

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That's it for this lecture.

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Thanks for watching in the next lecture.

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We will try and clear each of the frame so that you can see the individual ball at other time on the

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compass.

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Take care and by phone.