applying the colores to the terrain

hi,
i need to apply the colore for the terrain when i click the mouse, instead of applying the textures,please tell me how can i achieve this.

Colour painting is not supported by ETM, so you would have to implement it yourself. The key is to have a texture in the terrain material in a modulating pass and then edit that texture dynamically.

I would recommend downloading the ETL v3 source from SVN. It contains a class DynamicTexture which manages exactly that. You could use it as an inspiration.