There are three approaches which can be used separately or together to achieve the desired effect:
1) divide a wall in more than one segment horizontally, so you can choose a different texture for each segment
2) use more than one level (adjusting its properties) so vertically part of the wall is for the level 0, the upper portion for the level 1, and so on
3) simply put a thin box with the desired texture "glued" to the wall in the correct place, just as it were a painted paper
Regards.
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If a long walk every day were healthy, mailmen would be immortal.
