Combine Modes

All of the pattern dialogs have a combine-mode option allowing you to specify how the pattern will be combined with previously defined patterns within the same region. The two combine mode options are add and multiply.

Use add mode when you want a new pattern to add to the previous patterns. For example to make a plaid pattern, first place a 1/2 contrast grating into the region (the combine mode of this first grating is ignored), then create a second 1/2 contrast grating with a different orientation and place it into the region in add mode. The result is a full contrast plaid.

Use multiply mode when you want to modulate one pattern with another pattern. For example, to make a gabor pattern first place a full contrast grating into the region, then create a Gaussian pattern and place it into the region in multiply mode.