Written by Alcator.
This tutorial tries to explain one particular aspect of Replay creation: Continuous camera clips. CCCs is a serie of replay clips, launched by triggers, that create an illusion of one continuous shot. The reason you may want to use CCC instead of one long clip that passes along a complex path is that you don’t really know how fast or slow the car that is being shown will be – the racer might have scratched a wall here and there, or may be surprisingly fast due to perfect driving – and both of these cases result in the camera running away from the car and not showing it the way the trackmaker wanted.
One word of caution: This does not mean you should always use continuous camera shots in replays; many times a cut between wider shot and closer shot or between custom camera and racing camera works much better – just like in a movie. The good thing about CCC is that the spectator or viewer has perfect continuity in the ride – so a newbie racer may use it to learn the track and how to drive it, while from cut-o-plenty replays, this is harder.
For this tutorial, I have prepared this very simple test track. As you can see, it has a start, followed by roughly diagonal road with 2 boosters, a loop, and finish lane.
Now, what we will try to achieve is the following camera passage:
The camera will start on the right, observing the start. Once the car starts moving, the camera moves along the track and comes closer. Once the loop is entered, the camera moves to a place “inside” the loop section, thus showing the car above, doing the loop. And when the car leaves the loop, the camera starts moving behind the finish.
I always recommend to put a replay clip called “Idle” that shows the start. The thing is – the car doesn’t have to leave the start immediately, the player may be typing a message or do something else, and he may still be focused on during replay online. Don’t forget to make this clip “Keep playing”, so it doesn’t switch to follow-cam after the clip ends.
Both the start KEY and the end KEY of the camera TRACK have the same properties (you can copy one key to another by selecting the target KEY, and then Ctrl+leftclick on the source KEY. In this case, I’ve set the Interpolation to None, but you may leave Hermite or any other there – it doesn’t really matter in this case.
Once the car starts moving (enters the “Take-off clip”’s targetting cube), the second clip starts playing. This one features the camera movement. If you created this clip immediately after creating the Idle clip, your view should be at the same position as in Idle clip; if you moved the view, you will need to use the trick described later to make sure the camera positions connect.
This picture shows the end KEY of the camera TRACK on the Take-off clip; please note that I finetuned the Block End time to a moment when the car is just about to enter the booster where the loop clip starts. Again, this clip Keeps playing. As I mentioned before, you need the start KEY to be at the same position as the keys of the Idle clip’s camera track.
When you try to add the Thing clip (the loop clip), your view will return to the starting position of the Take off clip (or, actually, to the same position where it was when you created the Take off clip). There’s virtually no way you might move the view to the exact location where you want it using the arrow keys, and changing it using number input is too slow. Therefore, use the following “Pro” trick:
1)Select the Take-off clip and click the Export button at the top. Then give the clip any name you want and click the Save button. This will store the whole clip with all tracks into a Gbx file.
2)Once that is done, click on the “Thing” clip (empty so far). Then, click the Import button at the top, choose the previously saved clip and load it. Warning: Any content of the clip into which you import will be overwritten without comfirmation and without any way of UNDOing it!
3)Now, what you get in this way i two identical clips, each triggered by a different cube. But you don’t want to see the same camera movement twice, you want to continue from the point where the TakeOff clip ended. So, you want to COPY the END KEY of the TakeOff clip’s camera track to the START KEY of the Thing clip’s camera track. After you imported the Take off clip to The Thing clip, you have all the information for this copying in the same clip, so you can use Ctrl+leftclick to copy:
4) Select the Camera track in The Thing clip.
5) Click on the Start KEY of this track.
6)Ctrl+leftclick on the end KEY of this track – the end key will be copied to start key (and since the end key is the same as the end key in Take off clip, you just copied the end of take off clip to the start of The Thing clip!)
This is how the start key of The Thing clip will look like (you can compare it to one of the pictures before to see the values are the same; the car actually triggers the clip a little while after entering the cube, which is why the picture looks differently).
After you have this done, you only have to move the End key of the Thing clip to the end position of the camera for the loop. Something like this might work very well:
You can of course use this to copy the Idle clip as well (if you moved the view before creating Take off clip), just make sure that you have other than “None” interpolation selected.
In the same way, you can create the last clip of this track – from the End key of The Thing clip’s camera track to some position behind the finish.
When players watch this replay, they will see one beautiful continuous shot that shows them the right things at the right time.
For additional help, you can download the demonstrational track used in the examples above by clicking here!
February 26, 2007 at 1:53 pm
How about a download to the finished file?
February 26, 2007 at 5:34 pm
You mean a download of the track + replay done in the tutorial? If Alcator could provide that, it would be nice…
February 26, 2007 at 6:29 pm
Yes, that is what I mean
February 26, 2007 at 7:46 pm
I suggest you PM Alcator at TMX
Perhaps he can send you the track…
And if he does, I’d like to have it too for the article
February 26, 2007 at 10:37 pm
Why don’t you do it, it’s your blog…
February 27, 2007 at 11:15 am
Here’s the track on TMX:
http://united.tm-exchange.com/main.aspx?action=trackshow&id=159136#auto
February 27, 2007 at 3:59 pm
Ha, so you saw through that one, Djoszee
Thanks Alcator
March 15, 2007 at 7:19 am
Great write up… CTRL+Left Click? didn’t know that, thanks!
February 3, 2008 at 4:01 pm
Im tryin to make a TMU movie but dont know how to have more than one enviroment in it. Kinda like the TMU ttrailer. please help!!!!!
February 3, 2008 at 4:16 pm
Hmm… most movies I know are single-environment. Making several probably requires more skills with various movie-making programs, but that’s only a guess
Hopefully someone else can shine more light upon this
July 4, 2008 at 10:33 am
Y’know Nather, you may not be doing what i have in mind but i was thinking about doing a movie where i put a 3D model i want into CarCommon folder, and i make 1 big race out of every environment. is starts in snow, then bay, then desert, then rally, then stadium, then coast, then island. But to do that i need to code in a mediatracker for the intro, of my car flying down into that environment
quite hard to do, i may consult crusard as it was him who worked on the trump card and coded in fighter jets 