How to change the texture of objects?

[lmz123321]

Hi, thanks for the great work of virtual-home-unity.

I intend to make some custom modifications to the texture of objects (such as furniture, walls, and floors). Specifically, I hope to add some stains (e.g, black dots) to them so that they may look dirty.

I notice that the texture is set with a png/jpg/tga image, for example

• desk: https://github.com/xavierpuigf/virtualhome_unity/blob/master/Assets/3DModels/_Furnitures/Desks/Desk5/textures/Material%20_1598_AO.jpg
• bathroom: https://github.com/xavierpuigf/virtualhome_unity/blob/master/Assets/3DModels/_Bathroom/textures/jacuzzi-1.tga
• kitchen pan: https://github.com/xavierpuigf/virtualhome_unity/blob/master/Assets/3DModels/_Bathroom/textures/jacuzzi-1.tga

Can I directly modify these images and expect objects to have modified textures? Do I need, for example, recompile the unity source code to make my modification work?

If not, is there any way that I can do what I want?

(I am quite new to unity, so, please forgive me if this is a naive question) Thanks a lot for the help.