How hard is it to port games from the PC to other platforms?

How hard is it to port games from the PC to other platforms?

I am trying to learn game development with the Unreal Development Kit and Unity, trying both out, and trying to get an idea how they work. For now, I'm mostly focusing on PC games.
How hard is the technical aspect of porting a PC game that I made in the Unreal Development Kit or Unity to another platform, such as Play Station 3, or Xbox 360? is there some kind of option where we can just select the target platform from a combo box and press deploy, or do we need to modify the game for each platform?

Solutions/Answers:

Answer 1:

UDK and Unity can deploy to both the consoles you mentioned. Of course even in the best case, there are always going to be tweaks needed here and there since different platforms support different things (shader tech, controller types, and so on) and since optimisation may need to be done independently for the different platforms. There may be a few tweaks, or a mountain of them depending on the solution and platforms you intend to support. But yes, that’s part of the point of both UDK and Unity. What you’ll pay to support console platforms is a whole other matter.

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