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plurals

PO.isPointInPath() for stroked lines and polylines
primarykey
Id
11485316
data
AcceptedAnswerId
11535445
AnswerCount
3
ClosedDate
CommentCount
6
CommunityOwnedDate
CreationDate
2012-07-14T16:13:05.397
FavoriteCount
2
LastActivityDate
2017-10-03T15:15:27.793
LastEditDate
2012-07-16T17:41:24.007
LastEditorUserId
883970
OwnerUserId
883970
ParentId
0
PostTypeId
1
Score
7
ViewCount
1294
LastEditorDisplayName
text
Body
I need a mechanism for detecting mouseover event for lines, curves and polylines which have a various stroke width, I have already made such a mechanism for rectangles and ellipses, so I'm not new with canvas API. I do outline all of the drawn objects and detect mouse position over them, when rectangles or ellipses have a stroke width more than 1 pixel I expand the path so that it contains the border too. For lines and polylines it is difficult for me to understand how should I expand them when I have a lineWidth of 20 pixels for example. My question is: how to transform lines, curves and polylines in some shape path, so that this path could contain all their width? <img src="https://i.stack.imgur.com/OLZgL.png" alt="red - path, black - stroked path"> I would need that the path created would contain the line / curve width represented with black in this image. ----------Some more information---------- I will try to simplify the problem: We have 2 points (represented in red on the image below), they form a line that have a specific formula (y = mx + n), I need to dermine the formulas of perpendicular lines that are passing through these two initial points, after, it is necessary to determine the positions of the "blue" points, which are at the distance of the half of the value of context.lineWidth, when all points have been determined it is possible to create a new path using moveTo() and lineTo() sequence. This method should be applicable for quadratic and bezier curves using control points. The problem only remains in these mathematical calculations. <img src="https://i.stack.imgur.com/o3KQS.png" alt="">
Tags
<javascript><html5><html5-canvas>
Title
.isPointInPath() for stroked lines and polylines
singulars
PostAcceptedAnswerId
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
PostParentId
1. This table or related slice is empty.
PostTypePostTypeId
1. PTQuestion
UserLastEditorUserId
1. USmicnic
UserOwnerUserId
1. USmicnic
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
2. PO
 singulars
 PostTypePostTypeId
 PTAnswer
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 PO.isPointInPath() for stroked lines and polylines
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
2. VO
 singulars
 PostPostId
 PO.isPointInPath() for stroked lines and polylines
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
3. VO
 singulars
 PostPostId
 PO.isPointInPath() for stroked lines and polylines
 UserUserId
 USmicnic
 VoteTypeVoteTypeId
 VTBountyStart
CommentsPostId

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