Unity之贴图混合

有如下几种方式：

1.CPU端逐像素根据alpha通道进行叠加

        public void MergeTexture(Texture2D tt1, Texture2D tt2, int offsetX, int offsetY)
        {
            Texture2D newTex = new Texture2D(tt1.width, tt1.height, TextureFormat.ARGB32, false);

            newTex.SetPixels(tt1.GetPixels());

            for (int x = 0; x < tt2.width; x++)
            {
                for (int y = 0; y < tt2.height; y++)
                {
                    var PixelColorFore = tt2.GetPixel(x, y) * tt2.GetPixel(x, y).a;
                    var newY = tt1.height - offsetY - tt2.height + y;
                    var PixelColorBack = tt1.GetPixel(x + offsetX, newY) * tt1.GetPixel(x + offsetX, newY).a;
                    newTex.SetPixel(x + offsetX, newY, PixelColorFore+ PixelColorBack);
                }
            }
            newTex.Apply();
            System.IO.File.WriteAllBytes(Application.dataPath + "/" + tt1.name + ".png", newTex.EncodeToPNG());
            GameObject.Find("obj001").GetComponent<Renderer>().material.mainTexture = newTex;
        }

2.逐像素操作改为块操作

        public void MergeTexture(Texture2D tt1, Texture2D tt2, int offsetX, int offsetY)
        {
            Texture2D newTex= new Texture2D(tt1.width, tt1.height, TextureFormat.ARGB32, false);
            
            newTex.SetPixels(tt1.GetPixels());
            Color32[] colors = tt2.GetPixels32();
            // tt1.
            newTex.SetPixels32(offsetX, tt1.height - offsetY - tt2.height,tt2.width,tt2.height, colors,0);
            newTex.Apply();
            GameObject.Find("obj001").GetComponent<Renderer>().material.mainTexture = newTex;
        }

3.调用Unity的底层绘制接口在GPU上进行操作

        public Texture2D texture;        //Starting image.
        public Texture2D stampTexture;   //Texture to Graphics.Drawtexture on my RenderTexture.
        public float posX = 256f;        //Position the DrawTexture command while testing.
        public float posY = 256f;        //Position the DrawTexture command while testing.
        RenderTexture rt;                //RenderTexture to use as buffer.

        public void MergeTexture()
        {
            rt = new RenderTexture(1024, 1024, 32);           //Create RenderTexture 1024x1024 pixels in size.
            GameObject.Find("obj001").GetComponent<Renderer>().material.mainTexture = rt;   //Assign my RenderTexure to be the main texture of my object.
            RenderTexture.active = rt;
            Graphics.Blit(texture, rt);          //Blit my starting texture to my RenderTexture.
            RenderTexture.active = rt;                      //Set my RenderTexture active so DrawTexture will draw to it.
            GL.PushMatrix();                                //Saves both projection and modelview matrices to the matrix stack.
            GL.LoadPixelMatrix(0, 1024, 1024, 0);            //Setup a matrix for pixel-correct rendering.
                                                             //Draw my stampTexture on my RenderTexture positioned by posX and posY.
            Graphics.DrawTexture(new Rect(posX, posY, stampTexture.width, stampTexture.height), stampTexture);
            Texture2D png = new Texture2D(rt.width, rt.height, TextureFormat.ARGB32, false);
            png.ReadPixels(new Rect(0, 0, rt.width, rt.height), 0, 0);
            System.IO.File.WriteAllBytes(Application.dataPath + "/" + "nihao.png", png.EncodeToPNG());
            GL.PopMatrix();
            //Restores both projection and modelview matrices off the top of the matrix stack.
            RenderTexture.active = null;                    //De-activate my RenderTexture.
        }

 

转载请注明出处：https://www.cnblogs.com/jietian331/p/17836843.html