How to create an otio to render an OpenFX effect?

[garyo]

Hi; I'm a maintainer of OpenFX. I'm interested in using Toucan to test some OpenFX effects. I see a few .otio files in data/ so I get the basic structure for how you represent an OpenFX effect, but I'm wondering if these files were hand-constructed or if there's an app that can create them?
Also it seems toucan doesn't look in the standard OpenFX directories for plugins. Would a PR for that be accepted?

[darbyjohnston]

Hi, PRs are definitely welcome. When I worked on the OpenFX support I did the bare minimum to get the plugins working, so there are probably a number of things missing in the implementation.

The example .otio files were created by hand. At some point it would be nice to be able to edit them in the toucan viewer.

[garyo]

Not sure why, but on my Mac I can no longer build the superbuild -- various dependencies fail to build (starting with minizip, then OpenColorIO and lunasvg and so on.

But if it's helpful, here's a patch to find OpenFX plugins in the proper dirs -- not well tested because of the build problems but might be a decent start.

toucan-openfx-dirs.patch

[darbyjohnston]

I'm seeing the build errors as well, it looks like the latest macOS update might have removed some deprecated header files. I'll look into it...

[darbyjohnston]

I updated the PNG version and the build should be fixed now. I'll take a look at the patch, thanks.

[garyo]

Nice. My patch should work with that -- it does for me. You'll also need to set depth larger in Plugin.cpp in _findPlugins, maybe 8 or 10, because many plugins are in subfolders (plus the Contents/MacOS bundle structure on Mac).
Having done that surfaces some other issues with the OpenFX example plugins. The first one is that your gParamSuite is missing some API functions. Specifically paramSetGetPropertySet which is used by one of the examples. This is during

(lldb) p *OFX::Private::gParamSuite
(OfxParameterSuiteV1) {
  paramDefine = 0x00000001002d1470 (toucan-view`toucan::ImageEffectHost::_paramDefine(OfxParamSetStruct*, char const*, char const*, OfxPropertySetStruct**) at ImageEffectHost.cpp:259)
  paramGetHandle = 0x00000001002d1578 (toucan-view`toucan::ImageEffectHost::_paramGetHandle(OfxParamSetStruct*, char const*, OfxParamStruct**, OfxPropertySetStruct**) at ImageEffectHost.cpp:267)
  paramSetGetPropertySet = 0x0000000000000000
  paramGetPropertySet = 0x0000000000000000
  paramGetValue = 0x00000001002d169c (toucan-view`toucan::ImageEffectHost::_paramGetValue(OfxParamStruct*, ...) at ImageEffectHost.cpp:278)
  paramGetValueAtTime = 0x0000000000000000
  paramGetDerivative = 0x0000000000000000
  paramGetIntegral = 0x0000000000000000
  paramSetValue = 0x0000000000000000
  paramSetValueAtTime = 0x0000000000000000
  paramGetNumKeys = 0x0000000000000000
  paramGetKeyTime = 0x0000000000000000
  paramGetKeyIndex = 0x0000000000000000
  paramDeleteKey = 0x0000000000000000
  paramDeleteAllKeys = 0x0000000000000000
  paramCopy = 0x0000000000000000
  paramEditBegin = 0x0000000000000000
  paramEditEnd = 0x0000000000000000

This is during the Describe action:

(lldb) bt 10
* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
    frame #0: 0x0000000000000000
  * frame #1: 0x0000000121526f70 example-MultiBundle-support.ofx`OFX::ParamSetDescriptor::setParamSetHandle(this=0x0000600002544c30, h=0x000000016fdfda80) at ofxsParams.cpp:1031:24
    frame #2: 0x00000001214fbdcc example-MultiBundle-support.ofx`OFX::ImageEffectDescriptor::ImageEffectDescriptor(this=0x0000600002544c30, handle=0x000000016fdfda80) at ofxsImageEffect.cpp:451:5
    frame #3: 0x00000001214fbfc0 example-MultiBundle-support.ofx`OFX::ImageEffectDescriptor::ImageEffectDescriptor(this=0x0000600002544c30, handle=0x000000016fdfda80) at ofxsImageEffect.cpp:438:3
    frame #4: 0x00000001215048f0 example-MultiBundle-support.ofx`OFX::Private::mainEntryStr(actionRaw="OfxActionDescribe", handleRaw=0x000000016fdfda80, inArgsRaw=0x0000000000000000, outArgsRaw=0x0000000000000000, plugname="net.sf.openfx.gammaexample10") at ofxsImageEffect.cpp:2619:45
    frame #5: 0x00000001214efcf4 example-MultiBundle-support.ofx`OFX::FactoryMainEntryHelper<GammaExamplePluginFactory>::mainEntry(action="OfxActionDescribe", handle=0x000000016fdfda80, in=0x0000000000000000, out=0x0000000000000000) at ofxsImageEffect.h:178:14

[darbyjohnston]

Thanks, the changes look good, I created a PR for them as well as increasing the plugin search depth to 10:
#43

I just implemented the functions I was using for the toucan plugins, I'll look into adding the rest of them.