Silent crash with VL.IO.HTTP.WebServer's Skia help patch

[sebescudie]

Bonjour,

This is 2021.4 Preview 602 speaking. Accessing the URL provided in the “Serve a Rendered Image” help patch silently crashes vvvv.

Happened twice, so here are two event log entries that popped when this occurred :

<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
      <Provider Name="Application Error" /> 
      <EventID Qualifiers="0">1000</EventID> 
      <Version>0</Version> 
      <Level>2</Level> 
      <Task>100</Task> 
      <Opcode>0</Opcode> 
      <Keywords>0x80000000000000</Keywords> 
      <TimeCreated SystemTime="2021-11-08T13:00:39.6910799Z" /> 
      <EventRecordID>3133</EventRecordID> 
      <Correlation /> 
      <Execution ProcessID="0" ThreadID="0" /> 
      <Channel>Application</Channel> 
      <Computer>W10-LAPTOP</Computer> 
      <Security /> 
    </System>
  <EventData>
      <Data>vvvv.exe</Data> 
      <Data>2021.4.0.602</Data> 
      <Data>c328dac4</Data> 
      <Data>libglesv2.dll</Data> 
      <Data>2.1.15376.0</Data> 
      <Data>60ef17ce</Data> 
      <Data>c0000005</Data> 
      <Data>00000000000a5080</Data> 
      <Data>2a70</Data> 
      <Data>01d7d4a074c136ff</Data> 
      <Data>C:\Program Files\vvvv\vvvv_gamma_2021.4.0-0602-g8ed5e0ce29\vvvv.exe</Data> 
      <Data>C:\Program Files\vvvv\vvvv_gamma_2021.4.0-0602-g8ed5e0ce29\lib\x64\libglesv2.dll</Data> 
      <Data>ca6bf42a-a9f0-4514-9230-217ae8362fa8</Data> 
      <Data /> 
      <Data /> 
    </EventData>
  </Event>

<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="Application Error" /> 
    <EventID Qualifiers="0">1000</EventID> 
    <Version>0</Version> 
    <Level>2</Level> 
    <Task>100</Task> 
    <Opcode>0</Opcode> 
    <Keywords>0x80000000000000</Keywords> 
    <TimeCreated SystemTime="2021-11-08T12:59:13.0370604Z" /> 
    <EventRecordID>3129</EventRecordID> 
    <Correlation /> 
    <Execution ProcessID="0" ThreadID="0" /> 
    <Channel>Application</Channel> 
    <Computer>W10-LAPTOP</Computer> 
    <Security /> 
  </System>
    <EventData>
    <Data>vvvv.exe</Data> 
    <Data>2021.4.0.602</Data> 
    <Data>c328dac4</Data> 
    <Data>libSkiaSharp.dll</Data> 
    <Data>0.0.0.0</Data> 
    <Data>60e8bba2</Data> 
    <Data>c0000005</Data> 
    <Data>00000000000560d1</Data> 
    <Data>2908</Data> 
    <Data>01d7d4a01d2ad802</Data> 
    <Data>C:\Program Files\vvvv\vvvv_gamma_2021.4.0-0602-g8ed5e0ce29\vvvv.exe</Data> 
    <Data>C:\Program Files\vvvv\vvvv_gamma_2021.4.0-0602-g8ed5e0ce29\lib\libSkiaSharp.dll</Data> 
    <Data>d02442be-4e5b-4db5-9a3d-ccca45cd7aa5</Data> 
    <Data /> 
    <Data /> 
  </EventData>
  </Event>

Repro steps :

• Open the help patch
• Go to the mentioned URL
• Either the browser just displays a white image or vvvv silently exits

Cheers!

seb

[joreg]

a fix of the howto is in the latest nuget. due to skia now being fully gpu based we have to run ToRasterImage before accessing it from another thread, like so: