fix(line): fix visual gradient when coords are between two stops.

[pissang]

Brief Information

This pull request is in the type of:

• bug fixing
• new feature
• others

What does this PR do?

Fix clipped stops of gradient in line may be wrong when whole line are between the only two stops of visual map component

Fixed issues

#15885
#15877

Details

Before: What was the problem?

After: How is it fixed in this PR?

Misc

• The API has been changed (apache/echarts-doc#xxx).
• This PR depends on ZRender changes (ecomfe/zrender#xxx).

Related test cases or examples to use the new APIs

NA.

Others

Merging options

• Please squash the commits into a single one when merge.

Other information

[echarts-bot]

Thanks for your contribution!
The community will review it ASAP. In the meanwhile, please checkout the coding standard and Wiki about How to make a pull request.

The pull request is marked to be PR: author is committer because you are a committer of this project.

[plainheart]

Checked it again. The case in #15877 will show nothing because of the span limit.

echarts/src/chart/line/LineView.ts

Lines 327 to 329 in 2b63cd7

	if (coordSpan < 1e-3) {
	return 'transparent';
	}

Maybe we can make it smaller, for example, 1e-5 or 1e-8? Or set the tinyExtent like before?

[pissang]

@plainheart Created a new commit to revert the change described in https://github.com/apache/echarts/pull/15711/files#r735460339

[echarts-bot]

Congratulations! Your PR has been merged. Thanks for your contribution! 👍