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Two new instance variables

Listing 6 begins by declaring two new instance variables of types Texture2D and Vector2 named myTexture and spritePosition respectively.

The variable named myTexture will be used in the LoadContent method of Listing 6 to store a reference to a Texture2D object created from the image file with the Asset Name of gorightarrow (see Figure 7 ). It will also be used later in the overridden Draw method where it is the sprite being drawn.

The variable named spritePosition will be used later in the overridden Draw method to specify the location to draw the sprite. I will have more to say about this variable later.

The Texture2D class

Here is some of what the documentation has to say about the Texture2D class.

"Represents a 2D grid of texels .
A texel represents the smallest unit of a texture that can be read from or written to by the GPU(Graphics Processing Unit). A texel is composed of 1 to 4 components. Specifically, a texel may be any one of the available texture formatsrepresented in the SurfaceFormat enumeration.
A Texture2D resource contains a 2D grid of texels. Each texel is addressable by a u, v vector. Since it is a texture resource, it may containmipmap levels."

You can view a diagram of a texture resource containing a single 3x5 texture with three mipmap levels here . You can read what Wikipedia has to say about mipmaps here . The image used in this program doesn't have any mipmaps.

The SurfaceFormat enumeration

The SurfaceFormat enumeration defines numeric values representing about 50 different types of surface formats such as Rgba32 , which is defined as

"(Unsigned format) 32-bit RGBA pixel format with alpha, using 8 bits per channel."

The Texture Format of my image

For example, the Properties Window in Figure 7 shows the image that I used for my program to have a Texture Format property value of Color . The definition of the SurfaceFormat enumeration for Color is

"(Unsigned format) 32-bit ARGB pixel format with alpha, using 8 bits per channel."

Note that this is similar to Rgba32 except that the position of the alpha byte relative to the other three bytes is different.

A new SpriteBatch object

The code in the overridden LoadContent method of Listing 6 begins by instantiating a new SpriteBatch object and saving its reference in the reference variable named spriteBatch . (That variable is declared at the top of Listing 3 .)

Note that the statement that instantiates the SpriteBatch object in Listing 6 is already in the skeleton of the Game1 class when it first appears in the edit window of the Visual C# IDE. (See Listing 3 .)

The SpriteBatch class

According to the documentation , an object of the SpriteBatch class

"Enables a group of sprites to be drawn using the same settings."

The constructor for an object of the SpriteBatch class requires an incoming parameter that is a reference to the graphicsDevice of the current platform as type GraphicsDevice .

This can be confusing

GraphicsDevice is the name of an XNA class. It is also the name of a property of the Game class that is inherited into the Game1 class. The parameter that is passed to the constructor for the SpriteBatch object in Listing 6 is the inherited property.

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
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.
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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