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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

A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
Aislinn Reply
cm
tijani
what is titration
John Reply
what is physics
Siyaka Reply
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Jude Reply
Can you compute that for me. Ty
Jude
what is the dimension formula of energy?
David Reply
what is viscosity?
David
what is inorganic
emma Reply
what is chemistry
Youesf Reply
what is inorganic
emma
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
Krampah Reply
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
Sahid Reply
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
Samuel Reply
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Joseph Reply
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
Ryan
what's motion
Maurice Reply
what are the types of wave
Maurice
answer
Magreth
progressive wave
Magreth
hello friend how are you
Muhammad Reply
fine, how about you?
Mohammed
hi
Mujahid
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
yasuo Reply
Who can show me the full solution in this problem?
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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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