[v3.8.5] Fix the bug of tween color property of Sprite.

[dumganhar]

Re: #13229

Changelog

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Continuous Integration

This pull request:

• needs automatic test cases check.

  Manual trigger with @cocos-robot run test cases afterward.

• does not change any runtime related code or build configuration

  If any reviewer thinks the CI checks are needed, please uncheck this option, then close and reopen the issue.

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Compatibility Check

This pull request:

• changes public API, and have ensured backward compatibility with deprecated features.
• affects platform compatibility, e.g. system version, browser version, platform sdk version, platform toolchain, language version, hardware compatibility etc.
• affects file structure of the build package or build configuration which requires user project upgrade.
• introduces breaking changes, please list all changes, affected features and the scope of violation.

[dumganhar]

ESLint issues are fixed in this PR: #16948

So I don't fix them here.

[github-actions]

Interface Check Report

! WARNING this pull request has changed these public interfaces:

@@ -17225,8 +17225,9 @@
             /**
              * @deprecated since v3.5.0, this is an engine private interface that will be removed in the future.
              */
             _set_a_unsafe(alpha: number): Color;
+            [misc.extractPropsSymbol](): string[];
         }
         export function color(other: Color | string): Color;
         export function color(r?: number, g?: number, b?: number, a?: number): Color;
         /**
@@ -20531,8 +20532,9 @@
          * @returns @en The degree. @zh 角度。
          */
         export function radiansToDegrees(angle: any): number;
         export const BUILTIN_CLASSID_RE: RegExp;
+        export const extractPropsSymbol: unique symbol;
         export const BASE64_VALUES: number[];
     }
     export namespace path {
         /**

[dumganhar]

ESLint errors were fixed at #16948 , so don't fix them here.

[minggo]

I was thinking if we need to change Color implementation. Use r, g, b, a instead of _val.

[dumganhar]

Yes, it cause some issues that we need to use bit operation in many places.
And Color._var is public and it uses a number instead of 4 numbers which does save some memory.
So I think it's not the right time to make the change currently.

[minggo]

Yes, but Color._var is public and it uses a number instead of 4 numbers which does save some memory. I think, currently, it's not the right time to make the change.

I see. So i want to create a ticket in forum about it. I want to do it like this because it affects tween system now.

[dumganhar]

Fixed at #17021
Close this one.