fix: prevent geometry shift in Auto-Tangents when spread is 0

[Chetansahney]

Fixes #3822

Here is the fix to Spread==0 error and the AutoTangents error.
Based on the discussion : https://discord.com/channels/731730685944922173/731738914812854303/1481764902266736660

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request resolves an issue where the Auto-Tangents feature could inadvertently alter geometry when the 'spread' parameter was set to zero. The fix ensures that existing manipulator handles are correctly maintained under these specific conditions, preventing unwanted modifications and preserving the intended shape of the geometry.

Highlights

• Bug Fix: Addressed a bug in the auto_tangents function that caused unintended geometry shifts when the spread value was zero.
• Conditional Logic: Introduced a new conditional check within the auto_tangents function to explicitly preserve existing manipulator geometry when preserve_existing is true and spread is 0.0.

Changelog

• node-graph/nodes/vector/src/vector_nodes.rs
  • Added a conditional check within the auto_tangents function to prevent geometry shifts when spread is 0 and preserve_existing is true.

Activity

• No specific activity (comments, reviews, progress updates) has been recorded for this pull request yet.

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[gemini-code-assist]

Code Review

This pull request introduces a fix to prevent geometry shifts in the Auto-Tangents node when spread is 0 and preserve_existing is enabled. The added logic correctly preserves the existing manipulator groups in this specific case, preventing their handles from being reset. My review includes a minor suggestion to improve the code style and readability of the new block, aligning it with idiomatic Rust formatting.

[gemini-code-assist]

The added logic is correct. However, it can be formatted more idiomatically to improve readability. The temporary comment and extra blank line can be removed, and the if statement can be formatted using standard Rust style (opening brace on the same line).

 					if preserve_existing && spread == 0.0 {
 						new_manipulators_list.push(*curr);
 						continue;
 					}

[cubic-dev-ai]

No issues found across 1 file

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