It was a camera trick, but it was a camera trick because of two things:
1. Viewing angles were controlled by the camera. There was something up above him so no shot could show directly above him.
2. Editing allowed shots showing wires flashing to be cut out. I don't want to expose a levitation wire hiding secret here, but it was used for this in combination with editing to keep the wires from being seen. Thats why multiple performances were needed, and the multiple performances are the reason clouds move around from shot to shot.
However, no cgi was used. The person saying that is very wrong I think because I feel certain about how the levitation was done, and it was backed up by something he said in the video.
Luckily, the person is too stupid to figure out what was going on even though they figured something out confirming what I had thought was done in the levitation.
I've said it before and I will say it again, if you want to see how Angel did the building to building levitation just look in the background of the video. You see the "gimmick" if you can call it that more than once, although its not the gimmick he was using. The one he used wasn't ever shown in the video. And then of course they used some techniques to hide the wires.
Another thing that points to the building to building levitation not being cgi is the fact that Angel had his feet flat. I feel like his feet were flat to control at what point he turned to go to the other building. By turning his foot of both feet to the right someone could be signaled that he wanted them to turn right.
I don't know why Angel doesn't just decide that stuff ahead of time on levitations and tell the people, but he obviously must not since he uses his hands as signals to go up and down for the smaller levitations that need assistance.
Now as for the Luxor levitation, I don't think it was a camera trick. It was done for people live, it was at night, it was incredibly far away from people, and he had funny lighting to work with. I mean those conditions make it very easy to pull off a levitation.
But I think the close-up shots were camera tricks using cgi. The reason I think that is because you actually see one shot of angel looking down on the Luxor with a camera crew in the helicopter. So it seems like its not likely they would just fly over it for no good reason WITH the camera crew on board. I think they were filming the shots that were the close-up shots of Angel, and then edited in a cgi image of Angel.
As for the temp deal, its simple. They didn't have the light on, so it wasn't hot. And then when they did turn it on, I doubt it gets hot instantly. And the light above it wouldn't be hot since light is not actually hot. The heat would just radiate up into the air for some distance, and the further away it would be the cooler it would be. So Angel was high enough not to be in the heat, and the light had not been on long enough to heat up to start with.
And the levitation in the atrium in my opinion was pure cgi. I think he acted like he was going to jump, and they filmed shots of everyone reacting to that, got releases to use it in the episode, and then edited in cgi images of Angel floating down to the ground.
But really who knows unless we actually helped with the method. I mean there is more than one way to do most things anyway, so just because one would work and seems probably doesn't mean thats how it was done actually.
I loved the Luxor Light levitation though. It was a very good idea, and a very good way to use the Luxor as a perfect giant live stage for a large scale levitation. I do think its a little hypocritical of Angel to put down Daniel Holmes for doing a building to building levitation at night, and then do a levitation at night though...