从远程图像编辑Cubemap Skybox [英] Editing a Cubemap Skybox from remote image

问题描述

我需要从服务器下载图像，然后将其转换为Cubemap，最后将此CubeMap放在我的Skybox中.

I need to download an image from a server, then transform it in a Cubemap and finally put this CubeMap in my Skybox.

我使用C#.

我想到了以下代码:

public string url = "image/url.jpg";

void Update() {
    // When trigger, we start the process
    if (Input.GetKeyDown("f")) {

        // start Coroutine to handle the WWW asynchronous process
        StartCoroutine("setImage");
    }
}

IEnumerator setImage () {

    Texture2D tex;
    tex = new Texture2D(2048, 2048, TextureFormat.RGBA32, false);

    WWW www = new WWW(url);
    //Texture myGUITexture = Resources.Load("23") as Texture;

    Debug.Log (www.bytesDownloaded);
    Debug.Log (www.progress);
    Debug.Log (www.texture);

    yield return www;

    // we put the downloaded image into the new texture
    www.LoadImageIntoTexture(tex);

    // new cubemap 
    Cubemap c = new Cubemap(2048, TextureFormat.RGBA32, false);
    Color[] CubeMapColors;
    CubeMapColors = tex.GetPixels();
    c.SetPixels(CubeMapColors, CubemapFace.PositiveX);
    // we set the cubemap from the texture pixel by pixel
    c.Apply();

    //NewTexture.isPowerOfTwo = true;

    //Debug.Log (RenderSettings.skybox.GetTexture ("_Tex"));

    // We change the Cubemap of the Skybox
    RenderSettings.skybox.SetTexture("_Tex", c);
}

我注释了所有代码以解释我认为自己在做什么.

I commented all the code to explain what I think I am doing.

我做了这个技巧"来逐像素地创建Cubemap，因为从我能读到的其他人的帖子中似乎不可能用编辑器的方式来做到这一点(顺便说一句非常简单).

I made this "trick" of creating the Cubemap pixel by pixel because the Editor way to do it (which is incredibly simple by the way) seems to be not possible from other people posts I could read.

最终，结果只是一堆灰色像素.

Eventually, the result was just a bunch of grey pixels.

我真的不知道是什么在过程中造成了很大的麻烦，我看到的唯一阴影"点是TextureFormat.

I don't really know what screw up so much in my process, the only "shadow" point I see is the TextureFormat.

我选择RGBA32是因为当我查看我的Unity Editor时，我看到BC7格式，对于SetTexture和

I chose RGBA32 because when I look at my Unity Editor, I see BC7 format, which is error logged as non possible for SetTexture and from the doc they explain it may be decompressed in RGBA32.

当然控制台中没有剩余错误.

Of course there is no remaining error in the console.

我真的很惊讶没有一个简单的方法来做到这一点.我的意思是不一定要从http上获取图像并将其放在skybox中，而只需更改skybox的纹理即可.我想念什么吗?

I am really surprised there is not a easy way to do it. I mean not necessarily taking from http an image and put it in skybox, but just change the texture of a skybox. Am I missing something ?

推荐答案

我想我为您找到了解决方案.

I think I found a solution for you.

以下代码基本上是您代码的扩展.

The following code is basically an extension to your code.

我修复了一些困扰我的东西，但是代码却基本相同.

I fixed some stuff that was bothering me, but the code does basically the same.

using System.Collections;
using UnityEngine;

public class ReplaceCubemap : MonoBehaviour
{
    public string url = "your file name";
    public int CubemapResolution = 256;

    private Texture2D source;

    /// <summary>
    /// These are the faces of a cube
    /// </summary>
    private Vector3[][] faces =
    {
        new Vector3[] {
            new Vector3(1.0f, 1.0f, -1.0f),
            new Vector3(1.0f, 1.0f, 1.0f),
            new Vector3(1.0f, -1.0f, -1.0f),
            new Vector3(1.0f, -1.0f, 1.0f)
        },
        new Vector3[] {
            new Vector3(-1.0f, 1.0f, 1.0f),
            new Vector3(-1.0f, 1.0f, -1.0f),
            new Vector3(-1.0f, -1.0f, 1.0f),
            new Vector3(-1.0f, -1.0f, -1.0f)
        },
        new Vector3[] {
            new Vector3(-1.0f, 1.0f, 1.0f),
            new Vector3(1.0f, 1.0f, 1.0f),
            new Vector3(-1.0f, 1.0f, -1.0f),
            new Vector3(1.0f, 1.0f, -1.0f)
        },
        new Vector3[] {
            new Vector3(-1.0f, -1.0f, -1.0f),
            new Vector3(1.0f, -1.0f, -1.0f),
            new Vector3(-1.0f, -1.0f, 1.0f),
            new Vector3(1.0f, -1.0f, 1.0f)
        },
        new Vector3[] {
            new Vector3(-1.0f, 1.0f, -1.0f),
            new Vector3(1.0f, 1.0f, -1.0f),
            new Vector3(-1.0f, -1.0f, -1.0f),
            new Vector3(1.0f, -1.0f, -1.0f)
        },
        new Vector3[] {
            new Vector3(1.0f, 1.0f, 1.0f),
            new Vector3(-1.0f, 1.0f, 1.0f),
            new Vector3(1.0f, -1.0f, 1.0f),
            new Vector3(-1.0f, -1.0f, 1.0f)
        }
    };

    void Update()
    {
        // When trigger, we start the process
        if (Input.GetKeyDown(KeyCode.F))
        {

            // start Coroutine to handle the WWW asynchronous process
            StartCoroutine(setImage());
        }
    }

    IEnumerator setImage()
    {
        WWW www = new WWW(url);
        //Texture myGUITexture = Resources.Load("23") as Texture;

        Debug.Log(www.bytesDownloaded);
        Debug.Log(www.progress);
        Debug.Log(www.texture);

        yield return www;

        source = new Texture2D(www.texture.width, www.texture.height);
        // we put the downloaded image into the new texture
        www.LoadImageIntoTexture(source);

        // new cubemap 
        Cubemap c = new Cubemap(CubemapResolution, TextureFormat.RGBA32, false);

        Color[] CubeMapColors;

        for (int i = 0; i < 6; i++)
        {
            CubeMapColors = CreateCubemapTexture(CubemapResolution, (CubemapFace)i);
            c.SetPixels(CubeMapColors, (CubemapFace)i);
        }
        // we set the cubemap from the texture pixel by pixel
        c.Apply();

        //Destroy all unused textures
        DestroyImmediate(source);
        DestroyImmediate(www.texture);
        Texture2D[] texs = FindObjectsOfType<Texture2D>();
        for (int i = 0; i < texs.Length; i++)
        {
            DestroyImmediate(texs[i]);
        }

        // We change the Cubemap of the Skybox
        RenderSettings.skybox.SetTexture("_Tex", c);
    }

    /// <summary>
    /// Generates a Texture that represents the given face for the cubemap.
    /// </summary>
    /// <param name="resolution">The targetresolution in pixels</param>
    /// <param name="face">The target face</param>
    /// <returns></returns>
    private Color[] CreateCubemapTexture(int resolution, CubemapFace face)
    {
        Texture2D texture = new Texture2D(resolution, resolution, TextureFormat.RGB24, false);

        Vector3 texelX_Step = (faces[(int)face][1] - faces[(int)face][0]) / resolution;
        Vector3 texelY_Step = (faces[(int)face][3] - faces[(int)face][2]) / resolution;

        float texelSize = 1.0f / resolution;
        float texelIndex = 0.0f;

        //Create textured face
        Color[] cols = new Color[resolution];
        for (int y = 0; y < resolution; y++)
        {
            Vector3 texelX = faces[(int)face][0];
            Vector3 texelY = faces[(int)face][2];
            for (int x = 0; x < resolution; x++)
            {
                cols[x] = Project(Vector3.Lerp(texelX, texelY, texelIndex).normalized);
                texelX += texelX_Step;
                texelY += texelY_Step;
            }
            texture.SetPixels(0, y, resolution, 1, cols);
            texelIndex += texelSize;
        }
        texture.wrapMode = TextureWrapMode.Clamp;
        texture.Apply();

        Color[] colors = texture.GetPixels();
        DestroyImmediate(texture);

        return colors;
    }

    /// <summary>
    /// Projects a directional vector to the texture using spherical mapping
    /// </summary>
    /// <param name="direction">The direction in which you view</param>
    /// <returns></returns>
    private Color Project(Vector3 direction)
    {
        float theta = Mathf.Atan2(direction.z, direction.x) + Mathf.PI / 180.0f;
        float phi = Mathf.Acos(direction.y);

        int texelX = (int)(((theta / Mathf.PI) * 0.5f + 0.5f) * source.width);
        if (texelX < 0) texelX = 0;
        if (texelX >= source.width) texelX = source.width - 1;
        int texelY = (int)((phi / Mathf.PI) * source.height);
        if (texelY < 0) texelY = 0;
        if (texelY >= source.height) texelY = source.height - 1;

        return source.GetPixel(texelX, source.height - texelY - 1);
    }
}

代码的基本作用是:

• 从www
获取全景纹理
• 为每个面孔计算纹理
• 将生成的纹理分配给立方体贴图
• 收集垃圾
• 将立方体贴图分配给着色器

• Get the panorama texture from www
• For each face, calculates the texture
• Assign the generated texture to the cubemap
• Collect garbage
• Assign the cubemap to the shader

这篇关于从远程图像编辑Cubemap Skybox的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！