Mathematics and Physics in Unity game development 4 (adding gravity to object motion), unity Game Development

Mathematics and Physics in Unity game development 4 (adding gravity to object motion), unity Game Development

Adding gravity to object motion

Note:

• Use the series superposition algorithm y + = vy
• Acceleration on location vy + = GR
• The acceleration GR on the speed is the gravity acceleration. The unit of acceleration used in the computer is the special dot/F ^ 2 (pixel/square frame), instead of the 9.8 Mbit/s ^ 2
  (Meters/square seconds)
• Differentiation is an operation that is used to evaluate the differential coefficient. A differential coefficient refers to the change rate of a function about a specific value. This concept is often used in game development to evaluate a function change.

Using UnityEngine; using System. collections; // Add the gravity public class ParabolicMotionTest: MonoBehaviour in the object motion {// float posX = 0 in the X position of the object; // float posY in the Y position of the object = 0; // float speedX = 0 for the object in the x direction; // float speedY =-8 for the object in the y direction; // The upper right pixel of the screen is in the coordinate Vector3 ScreenRightTopPos Of The World Space; // the lower left pixel of the screen is in the coordinate Vector3 ScreenLeftBottomPos Of The World Space; // The half width float boxHalfWidth of the box; // run time float runTime; // gravity acceleration const float GR = 0.5f; // The Birth position of the object Vector2 bornPos; void Start () {// convert the pixels on the right of the screen to the coordinates of the World Space ScreenRightTopPos = Camera. main. screenToWorldPoint (new Vector3 (Screen. width, Screen. height, 0); // converts the pixels in the lower right of the screen to the coordinates of the World Space ScreenLeftBottomPos = Camera. main. screenToWorldPoint (new Vector3 (0, 0, 0); // The half width of the box, because the box is a square boxHalfWidth = transform. localScale. x * 0.5f; // the upper left corner of the birth location. bornPos = new Vector2 (ScreenLeftBottomPos. x + boxHalfWidth, ScreenRightTopPos. y-boxHalfWidth); // the initial position. transform is located in the upper left corner of the screen. localPosition = new Vector3 (bornPos. x, bornPos. y, 0);} void Update () {// detection. if the object goes out of the interface, send it to the bornPos point if (posX-boxHalfWidth> = ScreenRightTopPos. x | posX + boxHalfWidth <= ScreenLeftBottomPos. x | posY-boxHalfWidth> = ScreenRightTopPos. y | posY + boxHalfWidth <= ScreenLeftBottomPos. y) {// The runTime is set to 0 runTime = 0f;} // The displacement to the value posX = speedX * runTime + bornPos in each frame time. x; // posY = (0.5f * GR * runTime) + (speedY * runTime) + bornPos. y; // set the transform position of the frame. localPosition = new Vector3 (posX, posY, 0); // Time change value: runTime + = Time. deltaTime ;}}