增加观看距离？

Question

我想要做的是增加我的观看距离，这样我就可以看到超过10000f的物体我已经包含了一张图片，以帮助你理解我的意思，我想设置我的观看距离，比方说50000f所以我可以看到更远的物体。

下面是我的相机代码

---

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Media;
using Microsoft.Xna.Framework.Graphics;

namespace test1
{
public class ArcBallCamera
{
    //rotation
    public Matrix rotation = Matrix.Identity;
    //camera pos.
    public Vector3 position = Vector3.Zero;

    // Simply feed this camera the position of whatever you want its target to be
    public Vector3 targetPosition = Vector3.Zero;

    public Matrix viewMatrix = Matrix.Identity;

    public Matrix projectionMatrix = Matrix.Identity;

    private float zoom = 8000.0f;
    public float Zoom
    {
        get
        {
            return zoom;
        }
        set
        {    // Keep zoom within range
            zoom = MathHelper.Clamp(value, zoomMin, zoomMax);
        }

    }


    private float horizontalAngle = MathHelper.PiOver2;
    public float HorizontalAngle
    {
        get
        {
            return horizontalAngle;
        }
        set
        {    // Keep horizontalAngle between -pi and pi.
            horizontalAngle = value % MathHelper.Pi;
        }
    }

    private float verticalAngle = MathHelper.PiOver2;
    public float VerticalAngle
    {
        get
        {
            return verticalAngle;
        }
        set
        {    // Keep vertical angle within tolerances
            verticalAngle = MathHelper.Clamp(value, verticalAngleMin, verticalAngleMax);
        }
    }

    private const float verticalAngleMin = 0.01f;
    private const float verticalAngleMax = MathHelper.Pi - 0.01f;

    private const float zoomMin = 0.1f;
    private const float zoomMax = 8000.0f;


    // FOV is in radians
    // screenWidth and screenHeight are pixel values. They're floats because we need to divide them to get an aspect ratio.
    public ArcBallCamera(float FOV, float screenWidth, float screenHeight, float nearPlane, float farPlane)
    {
        if (screenHeight < float.Epsilon)
            throw new Exception("screenHeight cannot be zero or a negative value");

        if (screenWidth < float.Epsilon)
            throw new Exception("screenWidth cannot be zero or a negative value");

        if (nearPlane < 0.1f)
            throw new Exception("nearPlane must be greater than 0.1");

        this.projectionMatrix = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(FOV), screenWidth / screenHeight,
                                                                    nearPlane, farPlane);
    }

    public void Update(GameTime gameTime)
    {
        // Start with an initial offset
        Vector3 cameraPosition = new Vector3(0.0f, zoom, 0.0f);

        // Rotate vertically
        cameraPosition = Vector3.Transform(cameraPosition, Matrix.CreateRotationX(verticalAngle));

        // Rotate horizontally
        cameraPosition = Vector3.Transform(cameraPosition, Matrix.CreateRotationY(horizontalAngle));

        position = cameraPosition + targetPosition;
        this.LookAt(targetPosition);

        // Compute view matrix
        this.viewMatrix = Matrix.CreateLookAt(this.position,
                                              this.position + this.rotation.Forward,
                                              this.rotation.Up);
    }

    /// <summary>
    /// Points camera in direction of any position.
    /// </summary>
    /// <param name="targetPos">Target position for camera to face.</param>
    public void LookAt(Vector3 targetPos)
    {
        Vector3 newForward = targetPos - this.position;
        newForward.Normalize();
        this.rotation.Forward = newForward;

        Vector3 referenceVector = Vector3.UnitY;

        // On the slim chance that the camera is pointer perfectly parallel with the Y Axis, we cannot
        // use cross product with a parallel axis, so we change the reference vector to the forward axis (Z).
        if (this.rotation.Forward.Y == referenceVector.Y || this.rotation.Forward.Y == -referenceVector.Y)
        {
            referenceVector = Vector3.UnitZ;
        }

        this.rotation.Right = Vector3.Cross(this.rotation.Forward, referenceVector);
        this.rotation.Up = Vector3.Cross(this.rotation.Right, this.rotation.Forward);
    }


    public Matrix[] SetupEffectDefaults(Model myModel)
    {
        Matrix[] absoluteTransforms = new Matrix[myModel.Bones.Count];
        myModel.CopyAbsoluteBoneTransformsTo(absoluteTransforms);

        foreach (ModelMesh mesh in myModel.Meshes)
        {
            foreach (BasicEffect effect in mesh.Effects)
            {
                effect.EnableDefaultLighting();
                effect.Projection = projectionMatrix;
                effect.View = viewMatrix;
            }
        }
        return absoluteTransforms;
    }

}
}

Answer 1

我们看不到您如何创建ArcBallCamera，只是将构造函数的最后一个参数更改为50000即可完成工作，请参阅CreatePerspectiveFieldOfView文档here