Cinematics help pull players into a story, bringing players "down to eye-level" and connecting them to event in the in-game world, according to Brian Kindregan, lead writer on StarCraft 2: Heart of the Swarm and co-writer for Wings of Liberty.
Speaking in a panel at the 2013 Game Developers Conference today, Kindregan said cinematics help to humanize characters, something you don't get from watching sprites move around the screen. Cinematics bring players out of the basic world map and bring them into the heart of the action, allowing players to experience the "maximum amount of impact" of the story's emotions.
"The amount of story we tell in a mission or on a map is very very small," he said. "If I have a line of dialogue in a map that fires four or five times, people will swear they never heard the dialogue once. So we have very limited story we can tell in-game.
"However, when we put the story in a scripted scene, like a briefing or debrief, we are telling players that this is important, we're trying to make you look at it," he said. "But it doesn't necessarily mean it's a huge, impactful moment when a story turns. So when we put story in a cinematic, we're telling players it's very important. It indicates what kind of story the player is about to get.
Kindregan said the "Hopes and Fears" opening cinematic from the Heart of the Swarm expansion was the most difficult cinematic to create as it conveys a good chunk of the story. He said the team had to "define what victory looked like in making it a good cinematic," and that there were 13 different script drafts and animations before the team settled on the final one.
"Payoff is fun, when you set something up properly," he said. "Setting up is a lot harder. You're putting something out there that will mean something later, but you don't want people to feel like it's a setup."
"You can do anything you want to the cinematic so long as that central idea is there."
Every cinematic needs to have a central idea, Kindregan said, otherwise its inclusion won't work. Cinematics should answer questions, and not pose new ones without answering them.
"You can do anything you want to the cinematic so long as that central idea is there," he said. "If you add something and it breaks that central idea, it no longer works."
Kindregan said cinematics should have quick pacing, as prolonged scenes can cause players to lose interest. Even if these moments have payoffs, he said, it can still stunt a cinematic's story and emotional impact. Cinematics are "big, glossy and expensive," and the importance of each have to be justified from a story sense in order to be included. If the importance of the cinematic is lost, oftentimes developers should return to the foundations of the segment and re-determine what the most important parts are.
"The cinematic needs to leave players in a spot that makes them think, 'Great, I want to go hit play now,'" he said. "But the emotion of the end is wide open: you can have humorous, violence, bittersweet, sad, happy, all of those are on the table. The only thing you can't modulate or mess with is the tempo. The ending tempo needs to to be perfectly matched to whatever the following gameplay is going to be so the player is the correct mode when they hit play."
Powerful cinematics, according to Kindregan, build emotions on that one powerful central idea. The setup of the scene and the ending payoff have to be at the same level, and the ending must properly shift players into the right mood for gameplay.