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"Gets the milliseconds component of the time interval represented by thecurrent TimeSpan structure."

Therefore, the first line of new code in Listing 4 returns the elapsed time in milliseconds since the last call to the Update method.

Accumulate and compare elapsed time

Listing 4 adds the value in milliseconds to an accumulator variable named msElapsed each time the Update method is called.

Listing 4 also compares the accumulated value with the desired animation interval stored in msElapsed . If the accumulated value exceeds the desired animation interval, the accumulated value is set to zero and thebody of the if statement that begins in Listing 4 is executed to modify the drawing parameters.

Compute the location of the sprite to draw

The code in Listing 5 computes the location in pixel coordinates of the sprite image that needs to be drawn the next time the Draw method is called.

Listing 5 . Compute the location of the sprite to draw.

xStart = spriteCol * frameWidth; yStart = spriteRow * frameHeight;

That sprite image is identified by the intersection of the spriteCol column and the spriteRow row in Figure 1 .

The column and row values are used in conjunction with the width and height of the sprite images to compute the coordinates of the upper-left corner of thesprite image to be drawn. These values are stored in xStart and yStart , which will be used in the Draw method to select the correct image from I mage 1 and to draw that image.

The overall animation cycle

The program plays five animation cycles of the five sprite images in the top row of Figure 1 . These five cycles are played with the fast animation frame rate discussed earlier. This is controlled by a counter variablenamed funSequenceCnt . (This name was chosen because these images portray the dog running and jumping and having fun.)

Two animation cycles from the bottom row of sprite images

Then the program plays two animation cycles of the five sprite images in the bottom row of Figure 1 . These five cycles are played with the slow animation frame rate discussed earlier.

Pause and animate in the same location

During this period, the dog doesn't move across the game window but rather the animation cycles are played with the dog remaining in the same location.This is controlled by a counter variable named pauseSequenceCnt . (This name was chosen because the dog pauses and animates in the same location.)

After that, the overall cycle repeats.

Some complex logic

This is where the logic becomes a little complex and it remains to be seen how well I can explain it. However, my students are supposed to have theprerequisite knowledge that prepares them to dissect and understand complex logic directly from source code.

Adjust column and row counters

The drawing parameters have already been established to identity the sprite image that will be drawn the next time the Draw method is called. The code that follows is preparing for the sprite selection that willtake place after that one.

Increment the column counter and compare

Listing 6 increments the column counter and compares it with the number of columns in the sprite sheet in Figure 1 . If they match, Listing 6 resets the column counter to 0 and increments the funSequenceCnt to indicate that another one of the five cycles through the five images in the toprow of Figure 1 has been completed.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket 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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