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author | Asheem Mamoowala <asheem.mamoowala@mapbox.com> | 2017-12-12 13:22:33 -0800 |
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committer | Asheem Mamoowala <asheem.mamoowala@mapbox.com> | 2017-12-12 15:35:01 -0800 |
commit | a446b42328d44e809007f6266750d3d857de1bb1 (patch) | |
tree | cc92782cfe35bc9b1c4613ebeb963a8fa870217b | |
parent | 0ab8f9563b25001379ddcf79b4d8759a3998ca25 (diff) | |
download | qtlocation-mapboxgl-a446b42328d44e809007f6266750d3d857de1bb1.tar.gz |
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-rw-r--r-- | src/mbgl/renderer/sources/render_image_source.cpp | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/src/mbgl/renderer/sources/render_image_source.cpp b/src/mbgl/renderer/sources/render_image_source.cpp index 0844db39d9..e2e742167b 100644 --- a/src/mbgl/renderer/sources/render_image_source.cpp +++ b/src/mbgl/renderer/sources/render_image_source.cpp @@ -133,8 +133,12 @@ void RenderImageSource::update(Immutable<style::Source::Impl> baseImpl_, auto dMax = std::max(dx, dy); double zoom = std::max(0.0, std::floor(-util::log2(dMax))); - // Don't bother drawing the ImageSource unless it occupies >4 screen pixels - enabled = dMax * std::pow(2.0, transformState.getZoom()) > 2.0 / util::tileSize; + // Only enable if the long side of the image is > 2 pixels. Resulting in a + // display of at least 2 x 1 px image + // dMax is in tile coordinate units at z0, so scale by util::EXTENT and then + // by 2^z to get geometry coordinates at the current zoom. + // 1 gc unit = tileSize / extent pixels. + enabled = dMax * std::pow( 2.0, transformState.getZoom()) * util::tileSize > 2.0; if (!enabled) { return; } |