# SourceMods & TRIANGLE\_STRIP primitive?

**URL:** <https://discourse.libcinder.org/t/sourcemods-triangle-strip-primitive/1092>\
**Category:** Using Cinder\
**Created:** [March 15, 2018, 2:51pm UTC](https://discourse.libcinder.org/t/sourcemods-triangle-strip-primitive/1092 "2018-03-15T14:51:32Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![shortnotion](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.libcinder.org/shortnotion/32/253_2.png) [@shortnotion](https://discourse.libcinder.org/u/shortnotion)\
**Post date:** [March 15, 2018, 2:51pm UTC](https://discourse.libcinder.org/t/sourcemods-triangle-strip-primitive/1092/1 "2018-03-15T14:51:32Z")

</div>

I have a Custom geom::Source class which I’m trying to duplicate using SourceMods, as described here;

[https://forum.libcinder.org/topic/method-for-building-complex-geometry-from-geom-source?reply=true](https://forum.libcinder.org/topic/method-for-building-complex-geometry-from-geom-source?reply=true)

Something like this:

```
geom::SourceMods combined;
vec3 offset(0,0,-1.0f);
for (int x = 0; x < 10; x++) {
  combined &= CustomSource() >> geom::Translate(offset * vec3(i));
}

```

This seems to work fine with the default geometry sources, but my custom geom Source class uses the TRIANGLE\_STRIP primitive, which doesn’t seem to work (I tried a lot of variations, but basically when I changed my custom source’s primitive to TRIANGLES it finally worked).

Is the TRIANGLE\_STRIP primitive simply not supported for SourceMods or am I missing something?