首先在可以GameObject上挂上一个shader脚本，只要让GameObject有颜色就行，主要的采集像素点颜色的操作写在c#脚本中（这个脚本代码还是需要挂在Camera上）
接着还是直接上c#代码吧。
public class ColorPicker : MonoBehaviour
{
public BoxCollider pickerCollider;
private bool m_grab;
private Camera m_camera;
private Texture2D m_screenRenderTexture;
private static Texture2D m_staticRectTexture;
private static GUIStyle m_staticRectStyle;
private static Vector3 m_pixelPosition = Vector3.zero;
private Color m_pickedColor = Color.white;
void Awake()
{// 得到camera组件
m_camera = GetComponent();if (m_camera == null)
{Debug.LogError("You need to dray this script to a camera!");return;}// 为相机加上一个BoxCollider// 为了得到鼠标事件if (pickerCollider == null) {pickerCollider = gameObject.AddComponent();
// 确保collider在 camera's frustum中
pickerCollider.center = Vector3.zero;
pickerCollider.center += m_camera.transform.worldToLocalMatrix.MultiplyVector(m_camera.transform.forward) * (m_camera.nearClipPlane + 0.2f);
pickerCollider.size = new Vector3(Screen.width, Screen.height, 0.1f);
}
}
// 在左上角的正方形中绘制我们拾取到的颜色
public static void GUIDrawRect( Rect position, Color color )
{
if( m_staticRectTexture == null )
{
m_staticRectTexture = new Texture2D(1, 1);
}
if( m_staticRectStyle == null )
{
m_staticRectStyle = new GUIStyle();
}
m_staticRectTexture.SetPixel(0, 0, color);
m_staticRectTexture.Apply();
m_staticRectStyle.normal.background = m_staticRectTexture;
GUI.Box(position, GUIContent.none, m_staticRectStyle);
}
// 当相机完成渲染场景后将叫到OnPostRender（），并且这个消息将会被发送到所有挂在这个照相机的脚本上，用它获取（grab）这个屏幕
void OnPostRender() {
if (m_grab) {
m_screenRenderTexture = new Texture2D(Screen.width, Screen.height);
m_screenRenderTexture.ReadPixels(new Rect(0, 0, Screen.width, Screen.height), 0, 0);
m_screenRenderTexture.Apply();
m_pickedColor = m_screenRenderTexture.GetPixel(Mathf.FloorToInt(m_pixelPosition.x), Mathf.FloorToInt(m_pixelPosition.y));
// m_staticRectTexture.SetPixel(Mathf.FloorToInt(m_pixelPosition.x), Mathf.FloorToInt(m_pixelPosition.y),new Color(0,1,0,1));
// m_screenRenderTexture.Apply();
m_grab = false;
}
}
void OnMouseDown() {
m_grab = true;
// 记录鼠标位置去拾取该点的像素颜色值
m_pixelPosition = Input.mousePosition;
}
void OnGUI() {
GUI.Box(new Rect(0, 0, 120, 200), "Color Picker");
GUIDrawRect(new Rect(20, 30, 80, 80), m_pickedColor);
GUI.Label(new Rect(10, 120, 100, 20), "R: " + System.Math.Round((double)m_pickedColor.r, 4) + "\t(" + Mathf.FloorToInt(m_pickedColor.r * 255)+ ")");
GUI.Label(new Rect(10, 140, 100, 20), "G: " + System.Math.Round((double)m_pickedColor.g, 4) + "\t(" + Mathf.FloorToInt(m_pickedColor.g * 255)+ ")");
GUI.Label(new Rect(10, 160, 100, 20), "B: " + System.Math.Round((double)m_pickedColor.b, 4) + "\t(" + Mathf.FloorToInt(m_pickedColor.b * 255)+ ")");
GUI.Label(new Rect(10, 180, 100, 20), "A: " + System.Math.Round((double)m_pickedColor.a, 4) + "\t(" + Mathf.FloorToInt(m_pickedColor.a * 255)+ ")");
}
}
