# depthTestAgainstTerrain for only one primitive **URL:** \ **Category:** CesiumJS\ **Created:** [July 17, 2017, 3:31pm UTC](https://community.cesium.com/t/depthtestagainstterrain-for-only-one-primitive/5814 "2017-07-17T15:31:58Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![skyksandr](https://avatars.discourse-cdn.com/v4/letter/s/9dc877/32.png) [@skyksandr](https://community.cesium.com/u/skyksandr)\ **Post date:** [July 17, 2017, 3:31pm UTC](https://community.cesium.com/t/depthtestagainstterrain-for-only-one-primitive/5814/1 "2017-07-17T15:31:58Z")
Hello, I've seen thread few years ago with same question and the answer was - it is not possible. I want to ask is it still not possible now? What I want to achieve is shown on screenshot: [https://imgur.com/a/qtjCG](https://imgur.com/a/qtjCG) I want blue line to be shown always and white lines to be shown only if it above ground. Do you know the way I can achieve it? Or may be I can contribute to the terrain data with GPS data that 100% is above ground? Thank you. ---
**Author:** ![Rachel\_Hwang](https://avatars.discourse-cdn.com/v4/letter/r/d78d45/32.png) [@Rachel\_Hwang](https://community.cesium.com/u/Rachel_Hwang)\ **Post date:** [July 18, 2017, 3:24pm UTC](https://community.cesium.com/t/depthtestagainstterrain-for-only-one-primitive/5814/2 "2017-07-18T15:24:11Z")
Hi there, Unfortunately, we don’t currently have this functionality for polylines, although we offer more control over depth test distance for points, labels and billboards. You may be able to try some kind of workaround though. Check out this thread: [https://groups.google.com/forum/?hl=en#!searchin/cesium-dev/weak$20terrain|sort:relevance/cesium-dev/ZSGJAUqnGR0/2g\_M-n5PCAAJ](https://groups.google.com/forum/?hl=en#!searchin/cesium-dev/weak%2420terrain%7Csort:relevance/cesium-dev/ZSGJAUqnGR0/2g_M-n5PCAAJ) Hope that helps, - Rachel