I’ve been AFK for a while (holiday) so I just wanted to post the details of the final version of night at the museum I finished a few weeks ago that I delivered as part of my Udacity VR course.
The project went well (in that I passed) but I have to admit it was an exercise in restraint as much as anything. Like a lot of people I tend to have a big plans for everything I make but those plans are not always practical. This project was no exception. While I am ultimately happy with what I created, I do consider it very much a minimum viable project. When it comes to working on assignments like this there are a number of things to consider. First and foremost for me is available time.
I’m totally loving learning VR development, at this point I spend almost all my free time doing it. But working full time and having a young family is a busy time in life, so if I want to progress projects I have to be efficient with my time or things can stagnate. Also I currently pay for my studies via a monthly subscription so every extra month a project slips into comes with a significant extra cost.
Just to give you a few examples of compromises made on this project:
- Playing content at each of the stations was fairly limited and doesn’t have much finesse. For example the final build allows the user to play audio from all 5 stations at the same time, this leads to a fairly horrible experience if a user does this
- I reused a museum model from a previous project because it was faster than building my own. This means it’s not really an ideal setup. The space feels a little constrained and doesn’t provide much room to move about. Most real museums are quite spacious so it didn’t really fit the aesthetic I was aiming for
- I wasn’t that happy with the spatial audio implementation. The environment had a bit to much reverberated for my liking and given more time I would have improved this a bit
- There’s no environmental audio, just the content of the stations. I’d preferred to add some atmosphere to the scene just to add the the feel of the place
There are loads of other things that could be better about the final deliverable, but ultimately what was made “did the job”. Creating anything is always a series of compromises and I think delivering something you can live with and (resourcing permitting) can be built upon, is more important than getting things perfect. Perfection, after all, is the enemy of the shipped.
If you’re interested in the projects code, it’s all available on my Github account. Enjoy.
It’s hard to not have “all the feels” watching the above video (Ideally in VR if you’ve got a cardboard headset). The creators have done such an amazing job of crafting a great story with some seriously well thought out VR technique.
For example transitions/cuts within a 360 video like this can be very jarring, and require the user to reorientate themselves with each cut. In this video, they’ve used the fixed position of the car interior to ground the viewer. It’s extremely effective at controlling the flow of the experience.
The audio is also exceptional. Not only does the song to a great job of creating an emotional connection to the characters, but the changes in audio based on when the characters are inside or outside the car are just wonderful. Spatial audio at its finest.
Just a beautiful bit of work.
The more I create C# scripts in Unity the more I learn about optimising those scripts. With code there are 100s of ways to solve a problem, not all of them efficient, so learning to check your codes performance seems like a must.
Things to look for
So far I’ve come across a few simple things to look out for on the projects I’ve been coding. I’ll post more as I come across them in future.
- Anything that’s called every frame creates consistent load on the CPU, GPU or both. If what’s called is inefficient or large it will have a negative effect on frame rate. In VR this is particular bad given low frame rates can make your user physically sick. Be sure to look at what’s in the Update and FixedUpdate methods and do your best to optimise the code as much as possible.
- Working on mobile we will almost always be maxing out the graphics capability of the device. This effects the performance of the Update method. On the other hand FixedUpdated runs in sync with Unity’s physics engine. This will make sure your physics will be the most accurate and consistent. FixedUpdate is called every “physics step”, so is regularly used for adjusting physics (rigid body) objects. Make sure you always put your physics code in FixedUpdate.
- Avoid using GameObject.Find. It basically requires the system to cycle through all of the GameObjects in the game to find the right one, which obviously is expensive for the CPU. If you know what object we are using ahead of time, define the object at the top of the script and reference it that way. GameObject.Find is useful for testing out ideas, but that’s about it.
Part of my Night at the Museum project is adding audio descriptions to the objects on display. To do this in Unity I’m making use to the spatial audio capabilities of the Google Carboard SDK.
As with most things in Unity there’s a fairly reasoned logic to how this is done. You need three main things:
- An audio source. You can think of this as the media player, it is literally the source of the audio within your environment
- An audio clip. This is the actual audio file that will be played by your audio source. So think of this as the song that will be played by your media player
- An audio listener. This is effectivly your virtual ears within the virtual world. Normally this is attached to your main camera.
To give you an example of how I this works in practice. I first attached a GvrAudioListener to my main camera. This will allow my player to hear the sounds produced. Next add a GvrAudioSource to a GameObject you want to produce a sound. Now load your audio source (your media player) with an audio clip. There’s a few different supported formats, any old mp3 will work nicely. Just drag your MP3 into the audio click field of your GvrAudioSource. By default the audio will play on wake, so just hit play to enter game mode and you should hear your new audio right away.
For more information on the ins and outs of Google Cardboard Audio capabilities, check out the documentation.
If you find your audio doesn’t play, try clicking edit -> project settings -> audio and make sure the “Spatializer plugin” is set to Gvr.
Managed to get everything to compile to the phone again. Also, I can move about the place now 🙂
The big issue was around the legacy Google Cardboard SDK junking up the project. Completely deleting all SDK related files, old and new, then reinstalling the new was the quickest solution.
Once that was done, recreating key items like the events system and camera using the supplied GVR SDK components made life relatively straightforward.
Big thanks to synthercat for his wise guidance.
Check out the video below.
So that thing I broke, it’s getting fixed. Little by little, day by day.
So far I’ve managed to get:
- VR working properly again (at least I think I have)
- select objects again
- the FPS back over 60
Unfortunately I still can’t compile to my phone but hopefully, the weekend sorts that. It’s funny how breaking this thing has been possibly the most educational part of the course so far. I’m not saying I’d make a habit of it, but it was a net positive overall.
Here’s the latest update:
Wise words posted on the office noticeboard
Making stuff is difficult, especially when that stuff is new. This is something I’m all too aware of. I was progressing nicely with my Night at the Museum project when (in my wisdom) I decided to upgrade my production tools mid project. A word of advice, never do that.
Spending hours fixing a long list of issues is frustrating, but it isn’t a total loss. The key to success when you hit a bump in the road (like sucking at it, hating self etc) is to keep going! It’s not always easy but if you ever want to get good at anything, the key is preserving. Even in the face of self loathing and a general distrust of your own abilities.
When you’re doing something new, embracing the tough times and road blocks as an opportunity is key. You’ve got to see it as a way to toughen your resolve. If you can’t turn adversity into a win, then the that adversity will win and you’ll stop progressing.
So the next time you find yourself making a virtual museum experience and your:
- VR cameras stop working
- you can no longer select items
- your frame rate drops to a nausea inducing 27 fps
- you can no longer compile to a device
- all of the above is your fault because you made an idiotic decision
- delays cost you $300 per month in additional course fees (seriously send money now!)
Don’t give up, keep going! Not only that, tell other people about it. Seeing other peoples screw-ups is encouraging to others on the path to something new.