Simplify tilegrid API and internals #3815
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
ahocevar
force-pushed
the
tilegrid-no-surprises
branch
from
1fedef7
to
6e36188
Compare
ahocevar
force-pushed
the
tilegrid-no-surprises
branch
5 times, most recently
from
e8f32dc
to
240e683
Compare
|
Nice! |
|
|
||
| The first `tileCoord` argument of `ol.TileUrlFunctionType` now expects transformed tile coordinates instead of internal OpenLayers tile coordinates. Accordingly, `ol.tilegrid.TileGrid#getTileCoordForCoordAndZ` and `ol.tilegrid.TileGrid#getTileCoordForCoordAndResolution` now return transformed tile coordinates. | ||
| Previously, tile grids created by OpenLayers either had their origin at the top-left or at the bottom-left corner of the tile grid. To make it easier to for application developers to transform tile coordinates to the common XYZ tiling scheme, all tile grids that OpenLayers creates internally have their origin now at the top-left corner. |
There was a problem hiding this comment.
Don't you mean bottom-left here?
There was a problem hiding this comment.
No, it's the top-left corner of the extent now. But the tile coordinates increase upwards.
There was a problem hiding this comment.
"of the extent" was what I was missing. I got it.
There was a problem hiding this comment.
/easier to for/easier for/
Tile coord calculation was wrong in the case of reverseIntersectionPolicy for y coords, and for extents with +/- Infinity.
ahocevar
force-pushed
the
tilegrid-no-surprises
branch
from
240e683
to
f85fcf3
Compare
| var adjustX = reverseIntersectionPolicy ? 0.5 : 0; | ||
| var adjustY = reverseIntersectionPolicy ? 0 : 0.5; | ||
| var xFromOrigin = Math.floor((x - origin[0]) / resolution + adjustX); | ||
| var yFromOrigin = Math.floor((y - origin[1]) / resolution + adjustY); |
There was a problem hiding this comment.
Two reasons:
- The change from
(whatever) | 0toMath.floor(whatever)was necessary because(Infinity) | 0is0, but we need the result ofMath.floor(Infinity), which isInfinity. - The
yadjustment for snapping to screen pixels was previously incorrect, because screen coordinates increase downwards, but map coordinates increase upwards. The tests caught this problem after changing the origin to the top-left corner of the extent.
|
I just added questions for me to understand. I think this no-surprises branch is just great. Please merge. |
ahocevar
added a commit
that referenced
this pull request
Jun 19, 2015
Simplify tilegrid API and internals
|
|
||
| The first `tileCoord` argument of `ol.TileUrlFunctionType` now expects transformed tile coordinates instead of internal OpenLayers tile coordinates. Accordingly, `ol.tilegrid.TileGrid#getTileCoordForCoordAndZ` and `ol.tilegrid.TileGrid#getTileCoordForCoordAndResolution` now return transformed tile coordinates. | ||
| Previously, tile grids created by OpenLayers either had their origin at the top-left or at the bottom-left corner of the extent. To make it easier to for application developers to transform tile coordinates to the common XYZ tiling scheme, all tile grids that OpenLayers creates internally have their origin now at the top-left corner of the extent. |
There was a problem hiding this comment.
/easier to for/easier for/
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
From talking clients through all iterations of the tilegrid API when using custom tile url functions, and from experiences with the ol3-cesium integration of tile layers, it became clear that things are still not straightforward:
ol.TileCoordhas y values increasing from bottom to top.With these API simplifications, it is also possible to simplify tile grid handling internally. The Zoomify tile grid can finally be removed, because
ol.tilegrid.TileGridnow provides everything that the Zoomify tile source needs.