# Canvas black when viewing Pi via VNC

**URL:** <https://discourse.processing.org/t/canvas-black-when-viewing-pi-via-vnc/8185>\
**Category:** Processing for Pi\
**Created:** [February 7, 2019, 1:28pm UTC](https://discourse.processing.org/t/canvas-black-when-viewing-pi-via-vnc/8185 "2019-02-07T13:28:59Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![sciss](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/sciss/32/3580_2.png) [@sciss](https://discourse.processing.org/u/sciss)\
**Post date:** [February 7, 2019, 1:28pm UTC](https://discourse.processing.org/t/canvas-black-when-viewing-pi-via-vnc/8185/1 "2019-02-07T13:28:59Z")

</div>

Hello,

I noticed that while I can see the processing canvas fine on a monitor via HDMI, connecting to the Pi via VNC makes the canvas appear just as a black rectangle.

Is there a trick to overcome this limitation, at least for debugging, and have the canvas rendered also on a VNC client’s display?

Thanks

---

<div class="post-metadata">

**Author:** ![kll](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/kll/32/964_2.png) [@kll](https://discourse.processing.org/u/kll)\
**Post date:** [February 7, 2019, 3:09pm UTC](https://discourse.processing.org/t/canvas-black-when-viewing-pi-via-vnc/8185/2 "2019-02-07T15:09:40Z")

</div>

in the server  
++ options  
+++ troubleshooting  
++++ enable direct capture mode

 ![snap_0027](https://canada1.discourse-cdn.com/flex036/uploads/processingfoundation1/original/2X/4/4b5138252f5d2a425c1b6e1481abef9af25a6fd0.jpeg)

( this was called experimental … in older versions )

but first i should ask you if you use  
RPI full / fake KMS ( i do NOT here )

 ![snap_0028](https://canada1.discourse-cdn.com/flex036/uploads/processingfoundation1/original/2X/3/32b5a86c85dc23c11a9e1b9a1b7e1092f231a8aa.jpeg)

---

<div class="post-metadata">

**Author:** ![sciss](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/sciss/32/3580_2.png) [@sciss](https://discourse.processing.org/u/sciss)\
**Post date:** [February 7, 2019, 3:31pm UTC](https://discourse.processing.org/t/canvas-black-when-viewing-pi-via-vnc/8185/3 "2019-02-07T15:31:34Z")

</div>

Great, I will try that. Don’t know which GL mode I’m using; I started with off the shelf Raspbian Stretch, so it would be the default I guess.

---

<div class="post-metadata">

**Author:** ![kll](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/kll/32/964_2.png) [@kll](https://discourse.processing.org/u/kll)\
**Post date:** [February 7, 2019, 3:34pm UTC](https://discourse.processing.org/t/canvas-black-when-viewing-pi-via-vnc/8185/4 "2019-02-07T15:34:52Z")

</div>

see here:

> **[Technical](https://pi.processing.org/technical/)**
>
> Technical Notes Introduction The (original) Raspberry Pi contained an ARMv6 CPU, and 256 or 512 MB RAM. The Raspberry Pi 2 contains a quad-core ARMv7 CPU, and 1 GB of RAM. The Raspberry Pi 3 and 3+ contain a quad-core ARMv8 (64-bit) CPU, which can...

---

<div class="post-metadata">

**Author:** ![sciss](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/sciss/32/3580_2.png) [@sciss](https://discourse.processing.org/u/sciss)\
**Post date:** [February 7, 2019, 3:50pm UTC](https://discourse.processing.org/t/canvas-black-when-viewing-pi-via-vnc/8185/5 "2019-02-07T15:50:42Z")

</div>

Yes, it’s a mix of 3B and 3B+ machines; the raspi-config shows that G1 full is selected. I can confirm that it works when I select “enable direct capture mode”.

---

<div class="post-metadata">

**Author:** ![kll](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/kll/32/964_2.png) [@kll](https://discourse.processing.org/u/kll)\
**Post date:** [February 7, 2019, 3:53pm UTC](https://discourse.processing.org/t/canvas-black-when-viewing-pi-via-vnc/8185/6 "2019-02-07T15:53:16Z")

</div>

> [@sciss](#):
>
> the raspi-config shows that G1 full is selected.

not so sure it tell you anything about how it is set?  
usually it is on LEGACY,  
( would take a while to find where/how that is to find,  
just for info in KMS mode you loose all your display resolution settings  
( and are not even able to set them again! )  
and might not see full window in HDMI

the KMS mode i only use if there is a Processing example ( some P3D)  
what just not run in LEGACY mode

and again, i just say i did not test VNC in that mode… thats it.

? is it like a school class setup where you want check in from one computer  
onto many RPI? ( use fix IP-setup ??)