Screenshot

using System.IO;
using UnityEditor;
using UnityEngine;
using Object = UnityEngine.Object;

public class ScreenShot : EditorWindow {

    #region Window
    private bool panorama = false;
    private int height = 1024;
    private int width = 1024;
    private int angle = 180;
    private Space space = Space.World;
    private Camera cam;

    private void OnGUI() {
        EditorGUILayout.LabelField("Custom screenshot", EditorStyles.boldLabel);
        EditorGUIUtility.labelWidth = 100f;
        EditorGUILayout.Space();

        cam = EditorGUILayout.ObjectField("Camera", cam, typeof(Camera), true) as Camera;
        EditorGUILayout.Space();

        if(!cam)
            cam = Camera.main;

        panorama = EditorGUILayout.Toggle("Panorama", panorama);
        height = EditorGUILayout.IntSlider("Height", height, 64, 8192);

        if(!panorama)
            width = EditorGUILayout.IntSlider("Width", width, 64, 8192);
        else {
            angle = EditorGUILayout.IntSlider("Angle", angle, 1, 360);
            space = (Space)EditorGUILayout.EnumPopup("Rotation space", space);
        }

        GUI.enabled = cam;
        GUILayout.FlexibleSpace();
        if(GUILayout.Button("Shot!!!")) {
            var texture = panorama ? GetCameraRenderPanorama(cam, height, angle, space) : GetCameraRender(cam, width, height);
            SaveTexture(texture);
            DestroyImmediate(texture);
        }
        EditorGUILayout.Space();
        GUI.enabled = true;
    }
    #endregion

    #region MenuItens
    [MenuItem("Screenshot/High resolutions may crash unity", false, -200)]
    private static void Warn() { }

    [MenuItem("Screenshot/High resolutions may crash unity", true, -100)]
    private static bool WarnBool() { return false; }

    [MenuItem("Screenshot/Custom", false, -100)]
    private static void Custom() {
        var window = CreateInstance<ScreenShot>();
#if UNITY_5_0
        window.title = "Custom screenshot";
#else
        window.titleContent = new GUIContent("Custom screenshot");
#endif
        window.maxSize = window.minSize = new Vector2(245f, 160f);
        window.ShowUtility();
    }

    [MenuItem("Screenshot/720p", false, 0)]
    private static void Screenshot720p() {
        Screenshot(1024, 768);
    }

    [MenuItem("Screenshot/1080p", false, 0)]
    private static void Screenshot1080p() {
        Screenshot(1920, 1080);
    }

    [MenuItem("Screenshot/2160p (4k)", false, 0)]
    private static void Screenshot4k() {
        Screenshot(3840, 2160);
    }

    [MenuItem("Screenshot/Current resolution", false, 0)]
    private static void ScreenshotCurrent() {
        Screenshot(Camera.main.pixelWidth, Camera.main.pixelHeight);
    }

    [MenuItem("Screenshot/1024 x 1024", false, 200)]
    private static void Screenshot1024x1024() {
        Screenshot(1024, 1024);
    }

    [MenuItem("Screenshot/2048 x 1024", false, 200)]
    private static void Screenshot2048x1024() {
        Screenshot(2048, 1024);
    }

    [MenuItem("Screenshot/2048 x 2048", false, 200)]
    private static void Screenshot2048x2048() {
        Screenshot(2048, 2048);
    }

    [MenuItem("Screenshot/4096 x 1024", false, 200)]
    private static void Screenshot4096x1024() {
        Screenshot(4096, 1024);
    }

    [MenuItem("Screenshot/4096 x 2048", false, 200)]
    private static void Screenshot4096x2048() {
        Screenshot(4096, 2048);
    }

    [MenuItem("Screenshot/4096 x 4096", false, 200)]
    private static void Screenshot4096x4096() {
        Screenshot(4096, 4096);
    }

    [MenuItem("Screenshot/8196 x 1024", false, 200)]
    private static void Screenshot8196x1024() {
        Screenshot(8196, 1024);
    }

    [MenuItem("Screenshot/8196 x 2048", false, 200)]
    private static void Screenshot8196x2048() {
        Screenshot(8196, 2048);
    }

    [MenuItem("Screenshot/8196 x 4096", false, 200)]
    private static void Screenshot8196x4096() {
        Screenshot(8196, 4096);
    }

    [MenuItem("Screenshot/8196 x 8196", false, 200)]
    private static void Screenshot8196x8196() {
        Screenshot(8196, 8196);
    }

    [MenuItem("Screenshot/Panorama 720p 360º", false, 400)]
    private static void ScreenshotPanorama720p360() {
        SaveTexture(GetCameraRenderPanorama(Camera.main, 720, 360));
    }

    [MenuItem("Screenshot/Panorama 720p 180º", false, 400)]
    private static void ScreenshotPanorama720p180() {
        SaveTexture(GetCameraRenderPanorama(Camera.main, 720, 180));
    }

    [MenuItem("Screenshot/Panorama 1080p 360º", false, 400)]
    private static void ScreenshotPanorama1080p360() {
        SaveTexture(GetCameraRenderPanorama(Camera.main, 1080, 360));
    }

    [MenuItem("Screenshot/Panorama 1080p 180º", false, 400)]
    private static void ScreenshotPanorama1080p180() {
        SaveTexture(GetCameraRenderPanorama(Camera.main, 1080, 180));
    }

    [MenuItem("Screenshot/Panorama 2160p (4k) 360º", false, 400)]
    private static void ScreenshotPanorama4k360() {
        SaveTexture(GetCameraRenderPanorama(Camera.main, 2160, 360));
    }

    [MenuItem("Screenshot/Panorama 2160p (4k) 180º", false, 400)]
    private static void ScreenshotPanorama4k180() {
        SaveTexture(GetCameraRenderPanorama(Camera.main, 2160, 180));
    }
    #endregion

    #region Functions
    private static void Screenshot(int width, int height) {
        var texture = GetCameraRender(Camera.main, width, height);
        SaveTexture(texture);
        DestroyImmediate(texture);
    }

    private static void Panorama(int height, int angle) {
        var texture = GetCameraRenderPanorama(Camera.main, height, angle);
        SaveTexture(texture);
        DestroyImmediate(texture);
    }

    private static bool SaveTexture(Texture2D texture) {
        var path = EditorUtility.SaveFilePanel("Save screenshot", "", "screenshot", "png");

        if(path.Length == 0)
            return false;

        return SaveTexture(texture, path);
    }

    private static bool SaveTexture(Texture2D texture, string path) {
        try {
            var bytes = texture.EncodeToPNG();
            File.WriteAllBytes(path, bytes);
            Debug.LogFormat("Saved screenshot, size: {0}", EditorUtility.FormatBytes(bytes.LongLength));
            return true;
        }
        catch {
            return false;
        }
    }

    private static Texture2D GetCameraRender(Camera cam, int width, int height) {
        var texture = new Texture2D(width, height, TextureFormat.RGB24, false);
        var render = RenderTexture.GetTemporary(width, height, 24);

        RenderTexture.active = cam.targetTexture = render;
        cam.Render();
        texture.ReadPixels(new Rect(0, 0, width, height), 0, 0);

        RenderTexture.active = cam.targetTexture = null;
        RenderTexture.ReleaseTemporary(render);
        Object.DestroyImmediate(render);

        return texture;
    }

    private static Texture2D GetCameraRenderPanorama(Camera cam, int height, int angle, Space rotation = Space.World) {

        var width = height * angle / (int)cam.fieldOfView;
        var texture = new Texture2D(width, height, TextureFormat.RGB24, false);
        var render = RenderTexture.GetTemporary(1, height, 24);
        var euler = cam.transform.eulerAngles;

        RenderTexture.active = cam.targetTexture = render;

        cam.transform.Rotate(Vector3.up * angle / -2, rotation);

        for(int i = 0; i < width; i++) {
            EditorUtility.DisplayProgressBar("Creating panorama", "Rendering...", (float)i / width);
            cam.transform.Rotate(Vector3.up * angle / width, rotation);
            cam.Render();
            texture.ReadPixels(new Rect(0, 0, 1, height), i, 0);
        }

        cam.transform.eulerAngles = euler;

        EditorUtility.ClearProgressBar();
        RenderTexture.active = cam.targetTexture = null;
        RenderTexture.ReleaseTemporary(render);
        Object.DestroyImmediate(render);

        return texture;
    }
    #endregion
}