Objective
The brush aspect ratio should be easily understood, and predictable to use. A fine line should be achievable by creating a very squashed circle.
Design Revisions
| Revision | Current Design | Issues | Changes |
|---|---|---|---|
| 1. Use Normalized Aspect ratio | Range is from -20 to 20, 0 is undistorted, non-linear distortion up to 20 where there is a distortion clamp that limits the effect. | Historical reasons that are confusing in the GUI and confusing in the code | An aspect ratio of 1 is undistorted, 0, is very distorted, -1 flips the brush stamp, linear distortion |
MR Description
This is an aspect of the convert-to-artbox common branch that improves the brush aspect ratio behavior, simplifying the range and making brush distortions more intuitive and easier to understand in the user interface.
Changes
Normalized Aspect Ratio:
- Replaced the old non-linear aspect ratio range of
-20 to 20with a simplified linear range from-1 to 1, where1means undistorted,0represents high distortion, and-1flips the brush stamp. - The aspect ratio is now applied directly, and non-linear clamping behavior is removed.
- Special handling for
0aspect ratio is introduced to prevent problematic behavior, ensuring a minimal distortion of0.005when set to0.
- Replaced the old non-linear aspect ratio range of
Code Adjustments for Consistency:
- Updated the aspect ratio scaling logic in the
gimp_brush_transform_get_scale,gimp_brush_generated_transform_size, and related functions to reflect the linear aspect ratio system. - Refactored the calculation logic to remove historical non-linear clamps and simplify the math, providing a clearer, more predictable transformation.
- Updated the aspect ratio scaling logic in the
UI Simplifications:
- The brush editor now uses a
-1 to 1range for the aspect ratio, with linear steps for finer control. - Updated the PDB interface to reflect the new range, removing the old
-20 to 20bounds for both internal and user-accessible API calls.
- The brush editor now uses a
Benefit
- These changes simplify the brush aspect ratio behavior, making the interface easier to understand for users. The predictable linear distortion improves usability and allows finer control over the brush appearance. Additionally, the internal code is now cleaner and more maintainable, reducing complexity while ensuring consistent behavior across all brush-related features.