C# 在 Unity 3D 中使用触摸输入在地形上移动相机
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原文地址: http://stackoverflow.com/questions/11497085/
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Move Camera Over Terrain Using Touch Input in Unity 3D
提问by Rodney S. Foley
I am new to Unity and I am trying to figure out how to move the camera over a map/terrain using touch input. The camera would be looking down at the terrain with a rotation of (90,0,0). The terrain is on layer 8. I have had no problem getting it moving with keyboard, now I am trying to move to touch and it is very different if you want to keep expected usage on iOS.
我是 Unity 的新手，我试图弄清楚如何使用触摸输入在地图/地形上移动相机。相机将向下看地形，旋转（90,0,0）。地形在第 8 层。我用键盘让它移动没有问题，现在我试图移动到触摸，如果你想在 iOS 上保持预期的使用，这是非常不同的。
The best example I can think of on a built in iOS app is Maps where the user would touch the screen and that point on the map would stay under the finger as long as the finger stayed on the screen. So as the user moves their finger the map appears to be moving with the finger. I have not been able to find examples that show how to do it this way. I have seen may examples of moving the camera or character with the mouse but they don't seem to translate well to this style.
我能想到的内置 iOS 应用程序中最好的例子是地图，用户可以触摸屏幕，只要手指停留在屏幕上，地图上的那个点就会停留在手指下方。因此，当用户移动他们的手指时，地图似乎随着手指移动。我一直无法找到说明如何以这种方式执行此操作的示例。我见过可能用鼠标移动相机或角色的例子，但它们似乎不能很好地转化为这种风格。
Also posted on Unity3D Answers:
也发布在 Unity3D Answers 上：
http://answers.unity3d.com/questions/283159/move-camera-over-terrain-using-touch-input.html
http://answers.unity3d.com/questions/283159/move-camera-over-terrain-using-touch-input.html
采纳答案by Jerdak
Below should be what you need. Note that it's tricky to get a 1 to 1 correspondence between finger/cursor and the terrain when using a "perspective" camera. If you change you camera to orthographic, the script below should give you a perfect map between finger/cursor position and map movement. With "perspective" you'll notice a slight offset.
下面应该是你需要的。请注意，在使用“透视”相机时，很难在手指/光标与地形之间建立 1 对 1 的对应关系。如果您将相机更改为正交，下面的脚本应该会为您提供手指/光标位置和地图移动之间的完美映射。使用“透视”，您会注意到轻微的偏移。
You could also do this with ray tracing but I've found that route to be sloppy and not as intuitive.
你也可以用光线追踪来做到这一点，但我发现这条路线很草率而且不直观。
Camera settings for testing (values are pulled from the inspector so apply them there):
用于测试的相机设置（值是从检查器中提取的，因此将它们应用到那里）：
- Position: 0,20,0
- Orientation: 90,0,0
- Projection: Perspective/Orthographic
- 位置：0,20,0
- 方向：90,0,0
- 投影：透视/正交
using UnityEngine;
using System.Collections;
public class ViewDrag : MonoBehaviour {
Vector3 hit_position = Vector3.zero;
Vector3 current_position = Vector3.zero;
Vector3 camera_position = Vector3.zero;
float z = 0.0f;
// Use this for initialization
void Start () {
}
void Update(){
if(Input.GetMouseButtonDown(0)){
hit_position = Input.mousePosition;
camera_position = transform.position;
}
if(Input.GetMouseButton(0)){
current_position = Input.mousePosition;
LeftMouseDrag();
}
}
void LeftMouseDrag(){
// From the Unity3D docs: "The z position is in world units from the camera." In my case I'm using the y-axis as height
// with my camera facing back down the y-axis. You can ignore this when the camera is orthograhic.
current_position.z = hit_position.z = camera_position.y;
// Get direction of movement. (Note: Don't normalize, the magnitude of change is going to be Vector3.Distance(current_position-hit_position)
// anyways.
Vector3 direction = Camera.main.ScreenToWorldPoint(current_position) - Camera.main.ScreenToWorldPoint(hit_position);
// Invert direction to that terrain appears to move with the mouse.
direction = direction * -1;
Vector3 position = camera_position + direction;
transform.position = position;
}
}
回答by Pavel Galaton
I've come up with this script (I have appended it to the camera):
我想出了这个脚本（我已将其附加到相机）：
private Vector2 worldStartPoint;
void Update () {
// only work with one touch
if (Input.touchCount == 1) {
Touch currentTouch = Input.GetTouch(0);
if (currentTouch.phase == TouchPhase.Began) {
this.worldStartPoint = this.getWorldPoint(currentTouch.position);
}
if (currentTouch.phase == TouchPhase.Moved) {
Vector2 worldDelta = this.getWorldPoint(currentTouch.position) - this.worldStartPoint;
Camera.main.transform.Translate(
-worldDelta.x,
-worldDelta.y,
0
);
}
}
}
// convert screen point to world point
private Vector2 getWorldPoint (Vector2 screenPoint) {
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}
回答by eselk
Pavel's answer helped me a lot, so wanted to share my solution with the community in case it helps others. My scenario is a 3D world with an orthographic camera. A top-down style RTS I am working on. I want pan and zoom to work like Google Maps, where the mouse always stays at the same spot on the map when you pan and zoom. This script achieves this for me, and hopefully is robust enough to work for others' needs. I haven't tested it a ton, but I commented the heck out of it for beginners to learn from.
Pavel 的回答对我帮助很大，所以想与社区分享我的解决方案，以防它对其他人有帮助。我的场景是一个带有正交相机的 3D 世界。我正在开发一个自上而下的 RTS。我希望平移和缩放像谷歌地图一样工作，当你平移和缩放时，鼠标始终停留在地图上的同一位置。这个脚本为我实现了这一点，希望它足够强大，可以满足其他人的需求。我还没有对它进行过大量的测试，但我对它进行了评论，供初学者学习。
using UnityEngine;
// I usually attach this to my main camera, but in theory you can attach it to any object in scene, since it uses Camera.main instead of "this".
public class CameraMovement : MonoBehaviour
{
private Vector3 MouseDownPosition;
void Update()
{
// If mouse wheel scrolled vertically, apply zoom...
// TODO: Add pinch to zoom support (touch input)
if (Input.mouseScrollDelta.y != 0)
{
// Save location of mouse prior to zoom
var preZoomPosition = getWorldPoint(Input.mousePosition);
// Apply zoom (might want to multiply Input.mouseScrollDelta.y by some speed factor if you want faster/slower zooming
Camera.main.orthographicSize = Mathf.Clamp(Camera.main.orthographicSize + Input.mouseScrollDelta.y, 5, 80);
// How much did mouse move when we zoomed?
var delta = getWorldPoint(Input.mousePosition) - preZoomPosition;
// Rotate camera to top-down (right angle = 90) before applying adjustment (otherwise we get "slide" in direction of camera angle).
// TODO: If we allow camera to rotate on other axis we probably need to adjust that also. At any rate, you want camera pointing "straight down" for this part to work.
var rot = Camera.main.transform.localEulerAngles;
Camera.main.transform.localEulerAngles = new Vector3(90, rot.y, rot.z);
// Move the camera by the amount mouse moved, so that mouse is back in same position now.
Camera.main.transform.Translate(delta.x, delta.z, 0);
// Restore camera rotation
Camera.main.transform.localEulerAngles = rot;
}
// When mouse is first pressed, just save location of mouse/finger.
if (Input.GetMouseButtonDown(0))
{
MouseDownPosition = getWorldPoint(Input.mousePosition);
}
// While mouse button/finger is down...
if (Input.GetMouseButton(0))
{
// Total distance finger/mouse has moved while button is down
var delta = getWorldPoint(Input.mousePosition) - MouseDownPosition;
// Adjust camera by distance moved, so mouse/finger stays at exact location (in world, since we are using getWorldPoint for everything).
Camera.main.transform.Translate(delta.x, delta.z, 0);
}
}
// This works by casting a ray. For this to work well, this ray should always hit your "ground". Setup ignore layers if you need to ignore other colliders.
// Only tested this with a simple box collider as ground (just one flat ground).
private Vector3 getWorldPoint(Vector2 screenPoint)
{
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}
}
回答by sfdsa
using UnityEngine;
// I usually attach this to my main camera, but in theory you can attach it to any object in scene, since it uses Camera.main instead of "this".
public class CameraMovement : MonoBehaviour
{
private Vector3 MouseDownPosition;
void Update()
{
// If mouse wheel scrolled vertically, apply zoom...
// TODO: Add pinch to zoom support (touch input)
if (Input.mouseScrollDelta.y != 0)
{
// Save location of mouse prior to zoom
var preZoomPosition = getWorldPoint(Input.mousePosition);
// Apply zoom (might want to multiply Input.mouseScrollDelta.y by some speed factor if you want faster/slower zooming
Camera.main.orthographicSize = Mathf.Clamp(Camera.main.orthographicSize + Input.mouseScrollDelta.y, 5, 80);
// How much did mouse move when we zoomed?
var delta = getWorldPoint(Input.mousePosition) - preZoomPosition;
// Rotate camera to top-down (right angle = 90) before applying adjustment (otherwise we get "slide" in direction of camera angle).
// TODO: If we allow camera to rotate on other axis we probably need to adjust that also. At any rate, you want camera pointing "straight down" for this part to work.
var rot = Camera.main.transform.localEulerAngles;
Camera.main.transform.localEulerAngles = new Vector3(90, rot.y, rot.z);
// Move the camera by the amount mouse moved, so that mouse is back in same position now.
Camera.main.transform.Translate(delta.x, delta.z, 0);
// Restore camera rotation
Camera.main.transform.localEulerAngles = rot;
}
// When mouse is first pressed, just save location of mouse/finger.
if (Input.GetMouseButtonDown(0))
{
MouseDownPosition = getWorldPoint(Input.mousePosition);
}
// While mouse button/finger is down...
if (Input.GetMouseButton(0))
{
// Total distance finger/mouse has moved while button is down
var delta = getWorldPoint(Input.mousePosition) - MouseDownPosition;
// Adjust camera by distance moved, so mouse/finger stays at exact location (in world, since we are using getWorldPoint for everything).
Camera.main.transform.Translate(delta.x, delta.z, 0);
}
}
// This works by casting a ray. For this to work well, this ray should always hit your "ground". Setup ignore layers if you need to ignore other colliders.
// Only tested this with a simple box collider as ground (just one flat ground).
private Vector3 getWorldPoint(Vector2 screenPoint)
{
RaycastHit hit;
Physics.Raycast(Camera.main.ScreenPointToRay(screenPoint), out hit);
return hit.point;
}
}
