Teapot asked on GimpChat about using the multiplier options - since they didn't seem to have much effect on the outcome of path stroking.
I will try to explain in greater detail how they work, using some of the examples I have, but the main point to bear in mind is that the effects are not so noticeable when applied to paths that use only rotation to generate shapes - the basic mandala shapes for example.
Skip down to the images if you would prefer nor to read the boring bits.
General Information
The multiplier options, which in development were called modifier options, provide a means of adding small variations to the paths produced and drawn by PSCRSW. Why provide them? Well it seemed like a good idea at the time and anyway what is Gimp if it is not our toy to play about with.
The multipliers will only take affect if one of the ‘Pattern Multiplier Options’ is selected. These options allow you to apply various patterns of incremental values to the positioning and/or rotation of the path that creates the patterns. I tend to call this path the ‘copy’ path since it is the path that is repeatedly copied (although the actual path name is of no use in the filter.
The multiplier values are set by the user in the filter dialog. Start with small values and gradually increase these until you find an effect that pleases you. If you increase the value of the y offset multiplier but select a ‘Pattern multiplier option’ that uses the x offset you will not be able to see any difference in the filter output: Make sure that your pattern and multiplier types match.
The Multiplier pattern type describes the pattern that is used to apply the incremental values up to its maximum extent (this is set with the ‘Pattern multiplier steps’ value).
The Multiplier Patterns
Ripple pattern: adds a value that increases incrementally from zero up to the maximum and then decreases to the minimum (a value of 0 – the multiplier value) and then increases back to zero before repeating.
Ascend Jump pattern: adds a value that increases incrementally from zero up to the maximum and then jumps back to zero before repeating.
Descend Jump pattern: The opposite of Ascend Jump.
Zigzag Small pattern: The values yo-yo between zero and the maximum value.
Zigzag Large pattern: The values yo-yo between the maximum value and its minus equivalent.
Some example outputs on paths using the angle modifier with full revolution applied:
The copy path used in this section and the output without using multipliers:
- Rotation_Multipliers_Path.jpg # (27.09 KiB) Viewed 11401 times Thumbnail
The outputs have been overlaid to show the slightly different variations produced by each multiplier pattern:
- Rotation_Multipliers_Overlaid.jpg # (130.36 KiB) Viewed 11401 times Thumbnail
The effects of the patterns can be seen more clearly when using the x and/or y multipliers.
First image shows the simple path used in the following examples and the output without multipliers using the default filter settings and an X offset of 5 px. Note the even spacing between the lines, formed by the copy path, that make up the pattern:
- X_offset_Multipliers_Path.jpg # (13.59 KiB) Viewed 11401 times Thumbnail
The output using the Ripple pattern:
- X_offset_Multipliers_Ripple.jpg # (33.66 KiB) Viewed 11401 times Thumbnail
The output using the Ascend Jump pattern:
- X_offset_Multipliers_AscendJump.jpg # (39.14 KiB) Viewed 11401 times Thumbnail
The output using the Descend Jump pattern:
- X_offset_Multipliers_DescendJump.jpg # (40.94 KiB) Viewed 11401 times Thumbnail
And the output using one of the Zigzag patterns (not my favourite output):
- X_offset_Multipliers_Zigzag.jpg # (46.11 KiB) Viewed 11401 times Thumbnail
A final example with and without the use of multipliers using the copy path with 37 rotations:
No multipliers:
- X_offset_Multipliers_None_37.jpg # (47.57 KiB) Viewed 11401 times Thumbnail
With the Ripple pattern:
- X_offset_Multipliers_Ripple_37.jpg # (51.57 KiB) Viewed 11401 times Thumbnail
Conclusion:
Play play play
Copy_Rotate_Shift_Scale_Walk_v003.py #
