Interlacing Blend

[charlotteberr]

This pull request introduces a new operation interlacing blend. This operation can take in two pattern drafts and create a smooth transition between them using interlacement.

Parameters Used

• Blend Region Length: the length of the blend region
• Blend Center Percent: the center of the blend transition as a percent from 0 to 100
• Change Pattern Size: adds or subtracts from the common repeated pattern size
• Blend Direction: controls whether the blend runs horizontally or vertically

Implementation Details

• Input drafts are resized to a common width and height using the lowest common multiple (LCM) of their warp/weft counts.
• The blend region is constructed by interlacing columns (or rows for vertical) from each draft:
  - Outside the blend region, the output matches the original drafts.
  - Within the blend region, selection alternates between drafts with a bias determined by distance from the blend center.