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Why change the spider's position?

This change is position is necessary to prevent the same ladybug from registering a collision with the same spider during the next iteration of thegame loop. The forward movement of the spiders and the ladybugs each time they move is less than the dimensions of the intersecting rectangles. Therefore,without a purposeful shift in position of either the ladybug or the spider, the pair would continue to register collisions until the rectangles finally separatefrom one another.

Spiders don't die easily

As you read in the Preview section, if a black widow spider collides with a ladybug, it simply moves 128 pixels tothe right and changes into a green spider. If a green spider collides with a ladybug, it simply moves 128 pixels to the right and changes into a brownspider. Finally, if a brown spider collides with a ladybug, it is eaten and removed from the population of spiders. This is accomplished by the code in Listing 12 .

Listing 12 . Spiders don't die easily.

//If the collision was with a black widow // spider, cause it to reincarnate into a// green spider. if(target.Image.Name == "blackWidowSpider") {target.SetImage("greenspider",Content); }//If the collision was with a green spider, // cause it to reincarnate into a brown// spider. else if(target.Image.Name == "greenspider") {target.SetImage("brownSpider",Content); }//If the collision was with a brown spider, // it gets eaten. Remove it from the list of// spiders. else if(target.Image.Name == "brownSpider") {spiders.Remove(target); }// end else-if}//end if }//end for loopbase.Update(gameTime); }//end Update method

The code in Listing 12 is relatively straightforward.

The Name property

The first statement in Listing 12 shows why I needed to set an identifiable string value into the Name property of the Texture2D object referred to by image in Listing 2 and Listing 3 . I needed a way to determine the type of spider involved in each collision so that I could take the appropriate action when acollision was detected.

Killing the brown spider

The call to the spiders.Remove method in Listing 12 removes the target Sprite object's reference from the list of spiders. Since this is the only reference to the Sprite object, this action should make the memory occupied by the Sprite object eligible for garbage collection.

Is a Dispose Method needed?

However, I'm not certain that garbage collection is sufficient to free up all of the resources owned by the now defunct object and its image. It might also beadvisable to use a Dispose Method . At the time I am writing this, I simply don't know.

The end of the Update method

Listing 12 also signals the end of the overridden Update method.

The overridden Game.Draw method

The overridden Game.Draw method is shown in its entirety in Listing 13 .

Listing 13 . The overridden Game.Draw method.

protected override void Draw(GameTime gameTime) { spriteBatch.Begin();spiderWeb.Draw(spriteBatch);//draw background //Draw all spiders.for(int cnt = 0;cnt<spiders.Count;cnt++) { spiders[cnt].Draw(spriteBatch); }//end for loop//Draw all ladybugs. for(int cnt = 0;cnt<ladybugs.Count;cnt++) { ladybugs[cnt].Draw(spriteBatch); }//end for loopspriteBatch.End(); base.Draw(gameTime);}//end Draw method //-------------------------------------------------//}//end class }//end namespace

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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.
Bharti
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
Daniel
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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