DelayedCameraCapture

DelayedCameraCapture.cs

using System;
using System.IO;
using System.Collections;
using UnityEngine;

public class DelayedCaptureBehaviour: MonoBehaviour {
    public new Camera camera;
    public int delayFrames;
    public KeyCode targetKey;

    bool _capturing;

    void OnEnable() {
        _capturing = false;
    }

    void Update() {
        if (Input.GetKeyDown(targetKey) && !_capturing) {
            StartCoroutine(Capture(new CaptureArgs {
                frameCount = this.delayFrames,
                camera     = this.camera,
                ctx        = this
            }));
        }
    }

    struct CaptureArgs {
        public int frameCount;
        public  Camera camera;
        public DelayedCaptureBehaviour ctx;
    }

    IEnumerator Capture(CaptureArgs args) {
        Camera camera = args.camera;
        DelayedCaptureBehaviour ctx = args.ctx;
        
        ctx._capturing = true;

        bool enabled = camera?.enabled ?? false;
        if (camera) { camera.enabled = true; }

        // wait however many frames
        int frame = 0;
        while (frame < args.frameCount) {
            frame++;
            yield return null;
        }
        yield return new WaitForEndOfFrame();
        
        // create our target texture, and copy the camera's pixels into it
        Texture2D screenshotTex;
        if (camera?.targetTexture == null) {
            screenshotTex = ScreenCapture.CaptureScreenshotAsTexture();
        } else {
            // camera renders to a render texture
            RenderTexture.active = camera.targetTexture;
            screenshotTex = new Texture2D(camera.targetTexture.width, camera.targetTexture.height, TextureFormat.RGB24, false);
            screenshotTex.ReadPixels(new Rect(0, 0, screenshotTex.width, screenshotTex.height), 0, 0);    
        }
        
        // dump to desktop
        byte[] data = screenshotTex.EncodeToPNG();
        string dir = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory);
        const string fname = "screenshot.png";
        string fpath = dir + "/" + fname;
        if (File.Exists(fpath)) {
            File.Delete(fpath);
        }
        File.WriteAllBytes(fpath, data);

        if (camera && !enabled) { camera.enabled = false; }
        ctx._capturing = false;

        Debug.Log("saved screenshot!");
        UnityEngine.Object.Destroy(screenshotTex);
    }
}