c# - XNA - 保持更长时间跳得更高

Question

我正在为我的游戏寻找一种简单的方法，这样当你按住空格键时，你会跳得更高。当您“点击”时，您不会跳到最大高度。需要有一个最大值，但是是的，我不知道如何进行编程。

任何帮助，非常感谢。将给予反馈。谢谢。

Answer 1

在处理跳跃的更新函数中，您可以让它跟踪角色离开地面的时间，并让它的向上速度在一段时间后停止增加。

例如，类似下面的东西应该可以工作

class Player
{
    private const int gravity = 2; //force of gravity on the object
    private const int maxHeight = 5; //change as needed
    private const int msecsToMax = 1500; //change as needed

    private int yPos = 0;
    private int timeOffGround = 0;
    private yVel = 0;

    //other functions and stuff

    void update(GameTime gt)
    {
        //check if the player is on the ground and update as necessary
        if(isOnGround())
            timeOffGround = 0;
        else
            timeOffGround += gt.ElapsedGameTime.TotalMilliseconds;

        //update the player's velocity
        yVel -= isOnGround() ? 0 : gravity; //no velocity when on the ground
        if(Keyboard.GetState().IsKeyDown(Keys.SPACE) && timeOffGround < msecsToMax))
            yVel += (maxHeight / msecToMax);

        yPos += yVel;
    }
}

Answer 2

在跳跃的重音期间，Y 速度完全被功率曲线覆盖。在体面期间，重力接管。跳跃速度由jumpTime测量当前跳跃重音的时间的场控制。

首先你需要一些简单的全局变量，

public bool isJumping; //Is the player in a jump?
private bool wasJumping; //Did the player just exit a jump?
private float jumpTime; //Time the player has been in a jump (Useful for adding a power curve or to max out on jump height)

MaxJumpTime = .8f; //If you want to max out a jump, otherwise remove the relevant parts of the code
JumpLaunchVelocity = -3000.0f; //How much velocity to "jump" with, this may depend on your speed of your player, so it will need some ajustment

这是完成大部分工作的函数：

 private float DoJump(float velocityY, GameTime gameTime)
        {
            // If the player wants to jump
            if (isJumping)
            {
                // Begin or continue a jump
                if ((!wasJumping && IsOnGround) || jumpTime > 0.0f)
                {
                    //Do things like animate, or play a sound here
                    jumpTime += (float)gameTime.ElapsedGameTime.TotalSeconds;
                }

                // If we are in the ascent of the jump
                if (0.0f < jumpTime && jumpTime <= MaxJumpTime)
                {
                    // Fully override the vertical velocity with a power curve that gives players more control over the top of the jump (If you dont want this you can remove the Math.Pow)
                    velocityY = JumpLaunchVelocity * (1.0f - (float)Math.Pow(jumpTime / MaxJumpTime, JumpControlPower));
                }
                else
                    jumpTime = 0.0f;   // Reached the apex of the jump
            }
            else
            {
                // Continues not jumping or cancels a jump in progress
                jumpTime = 0.0f;
            }
            wasJumping = isJumping;

            return velocityY;
        }

在计算位置和内容时的更新中：

velocity.Y = DoJump(velocity.Y, gameTime);

如果遇到任何问题，请查看Platformer Starter Kit ！