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The variable declarations near the center of Listing 6 are new to this module.

The overridden LoadContent method

An abbreviated listing of the LoadContent method is shown in Listing 7 .

Listing 7 . Abbreviated overridden LoadContent method.

protected override void Update(GameTime gameTime) { spriteBatch = new SpriteBatch(GraphicsDevice);Font1 = Content.Load<SpriteFont>("Kootenay"); IsMouseVisible = true;//make mouse visible//code deleted for brevity //Position the on-screen text.FontPos = new Vector2(windowWidth / 2, 50); //Position the mouse pointer in the center of the// game window. Mouse.SetPosition(windowWidth / 2,windowHeight /2);}//end LoadContent

The font family

To begin with, note that this program displays text on the screen using the font family named Kootenay (see Figure 3 for a reference to this font-family name).

Make the mouse pointer visible

By default, the mouse pointer is not visible when it is in the game window. The code in Listing 7 sets the inherited variable named IsMouseVisible to true, which causes the mouse pointer to be visible.

Position the on-screen text

The code in Listing 7 causes the text to be centered horizontally, 50 pixels down from the top of the game window as shown in Figure 1 .

Set the initial position of the mouse pointer

The code in Listing 7 causes the initial position of the mouse pointer to be centered in the game window. (I will have more to say aboutthis later.)

End of the LoadContent method

Listing 7 also signals the end of the overridden LoadContent method.

The overridden Update method

An abbreviated listing of the overridden Update method begins in Listing 8 .

Listing 8 . Beginning of an abbreviated overridden Update method.

protected override void Update(GameTime gameTime) { //code deleted for brevity//Check to see if any spiders have made it to the // bottom edge.for(int cnt = 0;cnt<spiders.Count;cnt++) { if(spiders[cnt].Edge == 3) //One or more made it to the bottom edge.spiderCount += 1; }//end for loop

The code in in Listing 8 counts the number of spiders that make it to the bottom and collide with the bottom edge of the game window.

Moving the ladybug objects using the keyboard

The code required to service the keyboard is long, tedious, and repetitive, but is not complicated. That code is shown in Listing 9 .

Listing 9 . Service the keyboard.

//The following code is used to move one or the // other of two ladybugs using the arrow keys.// Press only the arrow keys to move one of the // ladybugs. Press the A plus the arrow keys// to move the other ladybug. //The ladybugs cannot be moved outside the game// window using the keyboard. //While an arrow key is pressed, the ladybug moves//five pixels per call to the Update method. //Get the state of the keyboard.KeyboardState keyboardState = Keyboard.GetState(); //Execute moves on one ladybug with arrow keys plus// the A or a key. if(keyboardState.IsKeyDown(Keys.Left)&&(keyboardState.IsKeyDown(Keys.A))&&(ladybugs[0].Position.X>0)) { ladybugs[0].Position = new Vector2( ladybugs[0].Position.X - 5, ladybugs[0].Position.Y); }//end ifif(keyboardState.IsKeyDown(Keys.Right)&&(keyboardState.IsKeyDown(Keys.A))&&(ladybugs[0].Position.X<(windowWidth - ladybugs[1].Image.Width))) { ladybugs[0].Position = new Vector2( ladybugs[0].Position.X + 5, ladybugs[0].Position.Y); }//end ifif(keyboardState.IsKeyDown(Keys.Up)&&(keyboardState.IsKeyDown(Keys.A))&&(ladybugs[0].Position.Y>0)) { ladybugs[0].Position = new Vector2( ladybugs[0].Position.X, ladybugs[0].Position.Y - 5); }//end ifif(keyboardState.IsKeyDown(Keys.Down)&&(keyboardState.IsKeyDown(Keys.A))&&(ladybugs[0].Position.Y<(windowHeight - ladybugs[1].Image.Height))) { ladybugs[0].Position = new Vector2( ladybugs[0].Position.X, ladybugs[0].Position.Y + 5); }//end if//Execute moves on the other ladybug with arrow // keys pressed but the A key not pressed.if(keyboardState.IsKeyDown(Keys.Left)&&!(keyboardState.IsKeyDown(Keys.A))&&(ladybugs[1].Position.X>0)) { ladybugs[1].Position = new Vector2( ladybugs[1].Position.X - 5, ladybugs[1].Position.Y); }//end ifif(keyboardState.IsKeyDown(Keys.Right)&&!(keyboardState.IsKeyDown(Keys.A))&&(ladybugs[1].Position.X<(windowWidth - ladybugs[1].Image.Width))) { ladybugs[1].Position = new Vector2( ladybugs[1].Position.X + 5, ladybugs[1].Position.Y); }//end ifif(keyboardState.IsKeyDown(Keys.Up)&&!(keyboardState.IsKeyDown(Keys.A))&&(ladybugs[1].Position.Y>0)) { ladybugs[1].Position = new Vector2( ladybugs[1].Position.X, ladybugs[1].Position.Y - 5); }//end ifif(keyboardState.IsKeyDown(Keys.Down)&&!(keyboardState.IsKeyDown(Keys.A))&&(ladybugs[1].Position.Y<(windowHeight - ladybugs[1].Image.Height))) { ladybugs[1].Position = new Vector2( ladybugs[1].Position.X, ladybugs[1].Position.Y + 5); }//end if

Questions & Answers

find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
how do they get the third part x = (32)5/4
kinnecy Reply
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
I'm not sure why it wrote it the other way
I got X =-6
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
is it a question of log
Commplementary angles
Idrissa Reply
im all ears I need to learn
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what is a good calculator for all algebra; would a Casio fx 260 work with all algebra equations? please name the cheapest, thanks.
Kevin Reply
a perfect square v²+2v+_
Dearan Reply
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Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
The answer is neither. The function, 2 = 0 cannot exist. Hence, the function is undefined.
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
how do you translate this in Algebraic Expressions
linda Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Xna game studio. OpenStax CNX. Feb 28, 2014 Download for free at https://legacy.cnx.org/content/col11634/1.6
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