1.2 Game0105r review  (Page 4/5)

Answer 38

False. When an object's reference is passed as a parameter to the System.out.println method, the toString method belonging to the object is executed automatically.

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Answer 37

False. Type double is the default representation for literal real numbers in Java.

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Answer 36

False.

This program instantiates objects from the following static top-level classes belonging to the class named GM2D01 :

• GM2D01.ColMatrix
• GM2D01.Line
• GM2D01.Point
• GM2D01.Vector

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Answer 35

True

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Answer 34

False. In 2D, the direction of a vector can be determined from the angle formed by the x-displacement and the line segment that represents the hypotenuseof a right triangle formed by the x and y displacements.

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Answer 33

True

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Answer 32

False. With regard to a vector, in 2D, the two values contained in a column matrix represent the displacements along a pair of orthogonal axes.

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Answer 31

False. Kjell tells us that the two (or three) real number values contained in the matrix to represent a vector (in 2D or 3D) specify a displacement of a specific distance from an arbitrary point in a specific direction.

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Answer 30

True

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Answer 29

True

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Answer 28

True

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Answer 27

False. Kjell tells us that we can represent a vector with two real numbers in a 2D system and with three real numbers in a 3D system.

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Answer 26

False. According to Kjell, "A vector does not have a position."

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Answer 25

True. According to Kjell, "A vector is a geometrical object that has two properties: length and direction." He also tells us, "A vector does not have a position."

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Answer 24

False. There will be many occasions when you, as a game programmer, will need to define the coordinate values for a point (or a set of points) that you have no intention of displaying on the screen. Instead, you will use thosepoints for various mathematical operations to produce something else that may or may not be displayed on the screen.

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Answer 23

False. Objects instantiated from the classes named Point2D.Double and Line2D.Double are intended primarily for rendering graphics on the screen and are not well suited for inclusion in mathematical operations. That is part of the rationale behind the development ofthe game-math library: separation of data objects that are suitable for mathematical operations from graphics objects .

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Answer 22

False. According to Kjell, the true line segment has no width, and therefore is not visible to the human eye. This is typically not the case with a linedrawn on the screen using an object of the Line2D.Double class.

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Answer 21

False. The default direction for increasing horizontal coordinate values in a Canvas object is from left to right across the screen.

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Answer 20

True

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Answer 19

True

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Answer 18

False. The class named Graphics2D is a subclass of (inherits from or is derived from) the class named Graphics .