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Test for a collision of the sprite with an edge

Listing 4 tests to determine if the upper-right corner of the sprite has encountered the right edge of the game window or if the upper-left corner of thesprite has encountered the left edge of the game window. If so, the sign of stepsX is changed to cause the direction of motion of the sprite to be reversed. You will see how the change in sign causes a reversal inthe direction of motion shortly.

Test for sprite out of bounds vertically

The code in Listing 5 tests to determine if the sprite has encountered the bottom or top edges of the game window. If so, the sign is changed on stepsY to cause the sprite to reverse its vertical direction of motion.

Listing 5 . Test for sprite out of bounds vertically.

if(((spritePosition.Y + myTexture.Height)>Window.ClientBounds.Height) ||(spritePosition.Y<0)) { stepsY *= -1;//Out of bounds, reverse direction}//end if

The logic in Listing 5 is essentially the same as the logic in Listing 4 with the difference being that Listing 5 deals with vertical motion and the top and bottom edges of the game window instead of horizontal motion and the left andright edges of the game window.

Change the current position of the sprite

Listing 6 changes the current position of the sprite by adding the incremental distances, stepX and stepY , to the current horizontal and vertical coordinates of the sprite.

Listing 6 . Change the current position of the sprite.

spritePosition.X += stepsX;//move horizontal spritePosition.Y += stepsY;//move vertical

Move to the right and down

The incremental distances were initialized with positive values in Listing 2 . Adding positive incremental distance values to the current coordinate valuescauses the position of the sprite to move to the right and down.

Reverse the direction of motion

The logic in Listing 4 and Listing 5 reverses the sign on the incremental distance values when the sprite encounters a left, right, top, or bottom edge ofthe game window.

Adding a negative incremental distance value to the current horizontal coordinate of the sprite causes it to be moved to the left. Adding a negativeincremental distance value to the current vertical coordinate of the sprite causes it to be moved up the screen.

No visible movement at this time

Simply changing the current horizontal and vertical coordinates of the sprite does not produce a visible change in position. The visible change in positionhappens later in the Draw method when the game window is cleared to a constant color and the sprite is redrawn in the game window in itsnew position.

The Draw method in this program was not modified relative to the version in the earlier module titled Xna0118-The XNA Framework and the Game Class . You can view the code in the Draw method in Listing 9 near the end of the module.

The remainder of the overridden Update method

The remainder of the overridden Update method is shown in Listing 7 .

Listing 7 . The remainder of the overridden Update method.

//The following statement is always required. base.Update(gameTime);}//end Update

Questions & Answers

Application of nanotechnology in medicine
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
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
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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