Fix 1-pixel flickering between tiles on dark styles #12145
Conversation
mpulkki-mapbox
force-pushed
the
mpulkki-fix-globe-tile-seams
branch
2 times, most recently
from
704f05c to
0c3f040
Compare
mpulkki-mapbox
force-pushed
the
mpulkki-fix-globe-tile-seams
branch
2 times, most recently
from
329af1c to
c6768ae
Compare
src/geo/projection/globe_util.js
Outdated
| const tileHeight = n - s; | ||
| const toUv = 1.0 / GLOBE_VERTEX_GRID_SIZE; | ||
| const x = tileWidth * toUv; | ||
| const y = -tileHeight / GLOBE_LATITUDINAL_GRID_LOD_TABLE[latitudinalLod]; |
There was a problem hiding this comment.
how about toUvX and we could also refactor 1 / GLOBE_LATITUDINAL_GRID_LOD_TABLE(..) to toUvY
There was a problem hiding this comment.
I think it's unnecessary to have a separate variable toUv anymore
| const xScale = padding / tileWidth + 1; | ||
| const yScale = padding / tileHeight + 1; | ||
| const padMatrix = [xScale, 0, 0, 0, yScale, 0, -0.5 * padding / x, 0.5 * padding / y, 1]; | ||
|
|
There was a problem hiding this comment.
The code here has now become more complicated, perhaps we could add a comment along the lines of:
// latLon = gridMatrix * (p_grid + scale * (p_grid - grid_center)) which implies
// latLon = grdiMatrix * (p_grid + scale * p_grid - scale * grid_center)
// and the part in parentheses is another transformation which results in:
// latLon = gridMatrix * padMatrix * p_grid
There was a problem hiding this comment.
This is fairly trivial transformation matrix composition. Perhaps I could add a comment or two about coordinate spaces.
There was a problem hiding this comment.
indeed I was trying to capture the transformation from spaces as I think that might not be trivial at all for a person encountering it for the first time.
mpulkki-mapbox
force-pushed
the
mpulkki-fix-globe-tile-seams
branch
from
c6768ae to
c3407d7
Compare
The greenish looking render test |
This pull request fixes the flickering issue between tiles (#11858) by extruding vertices of globe tiles slightly towards the neighbouring tiles. Based on empirical testing I found
0.5pixels to be enough to stitch seams on all of my test devices using different pixel ratios. It should be noted that the texture sampling is unaffected even though tiles are scaled up by a tiny amount. Any possible extra fragments will have their uvs clamped to range[0, 1].Fixes #11858
Launch Checklist
@mapbox/map-design-team@mapbox/static-apisif this PR includes style spec API or visual changes@mapbox/gl-nativeif this PR includes shader changes or needs a native portmapbox-gl-jschangelog:<changelog>Fix pixel flickering between tiles on darker styles in globe view.</changelog>