<![CDATA[SDK: Get total number of scenes and max length of a scene name]]>Hello Mark and Isadora developers,

I'm rewriting dbengali's plugin JumpByName ([http://troikatronix.com/troikatronixforum/discussion/768](http://troikatronix.com/troikatronixforum/discussion/768)) as I'd like to use it on Windows.
The way I proceed is quite simple:
  • browse all scenes in a 'for' loop
  • if the name of the currently requested scene (I use the GetSceneName_ function defined in IsadoraCallbacks.h) matches the requirements according to the parameters, jump to this scene
But this approach raises 2 problems:
  1. The 'for' loop needs a boundary. For now I hardcoded it in a constant, assuming that no Isadora project would use more than, say, 2000 scenes.
  2. The GetSceneName_ function requires a maxLen parameter, which seems to be the size of the string it fills with the scene name. I also used a constant, assuming that no one would have a scene name of 1000 characters.
I would like the performance to be optimal, not to mention the ugliness of these solutions. Hence these 2 questions:
  1. Is there a way to get the total number of scenes in an Isadora project dynamically (something like GetNumberOfScenes_ ?), or at least the maximum size of the scene array (if it's not dynamically assigned) ?
  2. Same question for the size of the scene name string (a constant maybe?)
Thanks in advance.
]]>https://community.troikatronix.com/topic/1108/sdk-get-total-number-of-scenes-and-max-length-of-a-scene-nameRSS for NodeTue, 21 Apr 2026 17:16:07 GMTWed, 12 Feb 2014 16:21:17 GMT60<![CDATA[Reply to SDK: Get total number of scenes and max length of a scene name on Wed, 05 Mar 2014 14:50:45 GMT]]>Oh... I see. No try/catch, just the return value compared to the kIzzyErr_SceneDoesntExist constant.

I'm feeling lazy to adapt my source right now, I'll keep the empty string comparison for now... works well too.
]]>https://community.troikatronix.com/post/10161https://community.troikatronix.com/post/10161Wed, 05 Mar 2014 14:50:45 GMT<![CDATA[Reply to SDK: Get total number of scenes and max length of a scene name on Tue, 04 Mar 2014 02:17:45 GMT]]>No problem, dbengali, thanks for your post anyway. The try/catch approach is interesting too, seems more robust in case of a change in the API.

]]>https://community.troikatronix.com/post/10159https://community.troikatronix.com/post/10159Tue, 04 Mar 2014 02:17:45 GMT<![CDATA[Reply to SDK: Get total number of scenes and max length of a scene name on Mon, 03 Mar 2014 18:53:31 GMT]]>Sorry again to disappear while you were working on this and not to save you time!

For #2 I made a similar choice, though I set the max length to 128\.  I believe I left a warning in the actor help about keeping scene labels less than 128 characters.  You were more generous :)
For #1 I also wonder if there is a way to find out the number of scenes somewhere, but I assumed that the scene list is maybe stored internally as a linked list rather than an array, in which case, there isn't necessarily a way to know the number of scenes other than navigating the list.  So, while iterating through the scenes looking for the search string, I just catch the error "kIzzyErr_SceneDoesntExist" to know if I have run past the end of the scene list, and thus can stop checking.  This conveniently avoids the need for a constant boundary on number of scenes.
hope this helps, even though it is a bit late.
]]>https://community.troikatronix.com/post/10157https://community.troikatronix.com/post/10157Mon, 03 Mar 2014 18:53:31 GMT<![CDATA[Reply to SDK: Get total number of scenes and max length of a scene name on Fri, 21 Feb 2014 11:13:43 GMT]]>Cool.. the name length is not such an issue..
thanks for putting in the hard work.

]]>https://community.troikatronix.com/post/10036https://community.troikatronix.com/post/10036Fri, 21 Feb 2014 11:13:43 GMT<![CDATA[Reply to SDK: Get total number of scenes and max length of a scene name on Thu, 20 Feb 2014 12:12:09 GMT]]>Just a little update. I finally managed to solve problem #1, I just replaced the 'for' loop with a do/while: knowing that GetSceneName_ fills the string parameter back with empty content (""), it can be tested as a loop end condition.

char loopCurrentSceneName[SCENE_NAME_MAX_LENGTH];
int i = 1; // scene index (one-based)
do
{
GetSceneName_(ip, inActorInfo, mode, i, SCENE_NAME_MAX_LENGTH-1, loopCurrentSceneName); // loopCurrentSceneName pointer now points to the scene name at current index
...
i++;
}while (strcmp(loopCurrentSceneName, "") != 0); // Loop while a scene name is found in scene list
As you can see, I didn't solve problem #2 (kept the SCENE_NAME_MAX_LENGTH constant defined in linked .h file), but after all it's no big deal.
]]>https://community.troikatronix.com/post/10017https://community.troikatronix.com/post/10017Thu, 20 Feb 2014 12:12:09 GMT