working with tile or brick patterns

hello. i'm very new to filterforge and haven't found exactly what i'm looking for in terms of how to create a tile or brick pattern with x% of red tiles and x% of blue tiles.

my goal is ultimately to load images of carpet squares, 4 of them, 3 that are very similar and 1 that is very different, then mix in the one that is very different by percentage.

the 4 carpet squares are actually rectangular, 2:1 ratio.

so lets say i have 3 dark charcoal colored carpet rectangles and 1 dark red carpet rectangle.

the designer wants to see what 25% red carpet pieces will look like randomly places within the charcoal carpet peices. then they would want to see what 15% mix looks like etc...

can you point me in the direction to do this?

i found that with "color control" you can load an image so i think i have that part down, i can setup 4 color controls each with it's on image loaded. i'm not sure how to mix them together after that though

thanks!