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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

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
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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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