Well, the trailer’s finally done – thank God! As with the last instalment I ran into a few issues along the way and got distracted by (necessary) bugfixes. Here’s a brief summary of how things panned out…
1. Oh, Bugger!
The thing about doing a trailer is that it makes you capture and scrutinize a shedload of gameplay footage AND deviate from your ‘learned’ methods of playing your own game. The consequence of both these things is that you uncover new bugs.
I ran into a few new bugs when working on this section of the trailer, most of them related to trying out different weapon types on the bosses. The most significant of these was that there were major deficiencies in the raycasting algorithm I was using to work out damage caused by explosive weapons. Turned out I was only calculating collisions based on axis-aligned bounding boxes (fine for smaller enemies, not fine for the more complex outlines of some bosses). So I had to redo the algorithm to work properly with convex polygons.
There were also issues in the way damage was distributed via ‘proxies’ (e.g. different parts of the same boss) which had to be looked at and problems with the ‘particle storm‘ weapon which were very fiddly to debug.
2. Enemies and Weapons
The next twenty-ish second chunk of the trailer aims to give an overview of the variety of weapons and enemies in the game. I split the into eight 2.5ish edits, taking the timings from the ‘Enter The Gungeon’ gameplay trailer which seemed to pace the edits about as fast as you can get whilst still making sense of what’s going on. Managed to squeeze a brief glimpse of the weapon upgrade process in here too – I wanted to convey visually that there’s upgrade paths available for the weapons.
The edits were made by grabbing a shedload of footage and then whittling it down to the ‘best’ short segment. This was a time-consuming process. I set up levels artificially so I was only dealing with one enemy at a time – ‘real’ gameplay footage proved too confusing as there was just too much going on most of the time.
3. Bosses
The next twenty seconds or so provide a five second ‘reveal’ of the first four bosses. That’s only enough time to sneak a look at the first attack phase of each but I think that’s enough – I’m bit worried about giving too much away as it is. As with the previous stage, I had to grab a ton of footage and then whittle it down to the ‘best’ edits. I also had to bear in mind the transitions between the edits whilst grabbing the footage, i.e. make sure the player was positioned onscreen at a point where a smooth transition would be possible so the viewer’s eye never has to make a disconcerting jump. I found this was particularly important when dealing with very short cuts. I had to re-shoot a couple of edits in both this section and the last in order to get these transitions smooth.
4. Out With A Bang
Initially this section was simply a glimpse at the final boss fight but I felt that just cutting to titles after this seemed rather lame. Consequently I worked on a more ‘scripted’ take where the player flies over the final boss and then takes it out with an R.P.G. It’s not possible to do this in the actual game (the fight has about five stages) but it acts as a significantly more punchy ending to the trailer.
I had to do multiple takes of this to get it right as I needed to fly over the boss, shoot it accurately, and then position the player accurately in the middle of the screen all without doing anything visually unappealing like crash into the edges of the screen or flipping left/right too much. there were plenty of bloopers – including some where I fired the R.P.G. in completely the wrong direction.
5. Outro Titles
I ended up doing these in code and positioning them over the last section in After Effects using chromakeying. Initially I thought I’d animate them in After Effects but I just found this far too fiddly. Fortunately I was able to use the in-game logo ‘entrance’ without having to change anything much so it was mainly about animating the subheadings with the release date etc. I like the way the smoke is still dissipating in the background as the titles appear!
6. Back To The Beginning
Lastly, I went back to the start of the trailer. I was every-so-slightly over 1:30 seconds so I edited the initial titles down a bit. As some people had commented that the player appeared to come ‘out of nowhere’ a bit (I kind of agreed with this) I tried panning across to the player before going back to the alien babies/abductions. This seemed to work. I also made the player blink in this cut to bring him to life a bit (done in After Effects) and added ‘abduction’ and ‘mutation’ text with pans and zooms with the rest of the action.
Now I think we’re finally there. Next task – Steam page and assets!
Dev Time: 8 days
Total Dev Time: approx 300 days
Raycasting Now Works Correctly With Convex Collision Polygons
Fixing ‘Proxy’ Collision Detection Bugs
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