How to get modified texture using shader, from material

Hi,

I am creating a scribbling tool. I have created all the functionality and written code in c#. Now I want to use the shader for that. I am having a problem with fetching modified texture from the material. It is the same I gave to the material.

void Start()
{
tex = new Texture2D(width,height,DefaultFormat.LDR,TextureCreationFlags.None);
Sprite sprite = Sprite.Create(tex,new Rect(0,0,width,height),new Vector2(0.5f,0.5f));
this.transform.GetChild(0).GetComponent<Image>().sprite = sprite;
scribbleMat = this.transform.GetChild(0).GetComponent<Image>().material;
scribbleMat.SetTexture("_MainTex",tex);

}

void Update()
{
if (Input.GetMouseButton(0))
{
Vector2 vec = getPoints(v,Input.mousePosition);
scribbleMat.SetVector("_PenPos",new Vector4(vec.x,vec.y,0,0));
Sprite s = this.GetComponent<Image>().sprite;
Texture2D texture = (Texture2D)scribbleMat.GetTexture("_MainTex");
s = Sprite.Create(texture,new Rect(0,0,texture.width,texture.height),s.pivot);
this.GetComponent<Image>().sprite = s;
// Color32[] c = ((Texture2D)scribbleMat.GetTexture("_MainTex")).GetPixels32();
// tex.SetPixels32(c);
// tex.Apply();

}
}

 

You should use render texture and something like "Blit" or "DrawMeshNow" to make rendering happen.