There are (ussually) 3 things to manipulate: texture for the 3D view in OpenGL, vectorial pattern for 2D views (elevation, section) and cinerender settings for photorendering.
You could stretch the 15x15 texture to be 45x90, but the grooves will not look so nice.
You can easily manipulate a 15x15 vectorial pattern to be 45x90.
The cinerender surface settings could be either a texture or it could be a procedural shader. Texture stretching is the same as with the 3D OpenGL one: grooves might not look good. Procedural shader should just adapt to look good when you change the 'Size' settings.
All that said, if you create a new surface from library (catalog), I think you will find there are rectangular tile presets to choose from that would look nicer when you upscale them to 45x90.
Erwin Edel, Project Lead, Leloup Architecten
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