How to merge two textures of different size?

Questions & Answers
1

I’m developing 2d Tower Defense game and I want to be able to modify background texture(draw textures of dead units on it).
I don’t want to use separate objects to put on top of the background because I assume this will significantly slow down my game (number of units suppose to be VERY large).

I’ve found a code that allow to merge textures of the same size:

var tex1 : Texture2D;
var tex2 : Texture2D;

function Start (){

        var pix1 = tex1.GetPixels32();
        var pix2 = tex2.GetPixels32();

        if (pix1.Length != pix2.Length) {
            Debug.Log("Images need to be the same size");
            return;
        }

        for (var i = 0; i < pix1.Length; i++) {

            if (pix2*.a != 0) {*

pix1 = pix2*;*
}
}

tex1.SetPixels32(pix1);
tex1.Apply();

renderer.material.mainTexture = tex1;
}
How can I modify this code to be able to merge background texture with small textures (of dead units) at specific position?

2

The solution is here:

#pragma strict

var texToDraw : Texture2D;
var x: int;
var y: int;

function Start (){
		var background : Texture2D = Instantiate(renderer.material.mainTexture);
        var pix1 = background.GetPixels32();
        var pix2 = texToDraw.GetPixels32();

	    for (var j = 0; j < texToDraw.height; j++){
        	for (var i = 0; i < texToDraw.width; i++) {
				pix1[background.width/2 - texToDraw.width/2 + x + i + background.width*(background.height/2-texToDraw.height/2+j+y)] = pix2[i + j*texToDraw.width];
        	}
        }
        
        background.SetPixels32(pix1);
        background.Apply();
        renderer.material.mainTexture = background;
}