Read our expert advice for making the most of effects in game level development, from optimisation to environments
Creating in-game effects is a delicate balance between perceived realism and what’s technically feasible.
Done properly, effects make a game feel immersive and highlight gameplay elements in a way that goes undetected by the player.
Here, we pass on advice that will help you to raise the bar for game effects by making them stand out, while still allowing for limitations in real game development engines. We’ll also see how certain attributes can be adjusted and when they should be traded off against changes in other areas to achieve various looks.
The tips range from how junior artists can make in-game effects that will gain approval and building a library of multi-purpose emitters, through to the things experienced VFX artists moving from film into games will want to think about.
We’ll also explore the issues that the VFX artist needs to consider when interacting with other departments, from animation to environment, sound and GUI.
NB: This specific set of advice is based on the assumption of a basic knowledge of particle systems and how to manipulate them.
Images from Brink, courtesy of Splash Damage
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If you’re able to step frame-by-frame through a Hollywood feature film effect, you’ll pretty much see how the pros set up an explosion.
It’s useful to do the same with games to see how other artists have approached an effect – but be careful with either of these, because you risk your effects becoming derivative.
Break the reference into its constituent elements, then translate these into the attributes and primitives you have in your software.
For example, you could translate a shockwave as a torus-shaped emitter shooting out particles in a radial direction; adding drag and increasing the scale will slow these down and create a bloom as the wave settles.
Combine these with a drop in opacity and added rotation, and they’ll fade out in a wispy manner.
You want to excite people during high-intensity firefights with plenty of impacts, but throwing in lots of fire and spark sprites with high velocities may confuse and disorientate players.
Instead, combine bright spark and fire textures with high incandescence set to a short lifespan.
Moving large numbers of small elements – such as blood dots, debris and sparks – quickly and with diminishing scales gives a violent effect without adversely reducing frame rates.
Use highly opaque smoke textures to punch out from the fire and create follow-through. Consider how many instances an effect will be played over, then dissipate the effect appropriately.
Knowing the rate of fire for a particular weapon will serve as a guide. Having multiple instances of slow-settling smoke undoubtedly looks cool, but it may also grind the frame rates to a complete halt.
Does it make sense to have blood and gore flying out of a player when their animation doesn’t flinch? Does shrouding an object in fire and smoke look appropriate when the object itself remains unscathed? Consider how appropriate the effect is in-game.
If a certain calibre of bullet leads to an animation of an enemy being floored and incapacitated, the blood effect should be several times bigger than a lower-calibre bullet injuring an enemy.
When blowing up items, see if you can tweak the timings for switching between damaged and undamaged states – particle effects have to cover this model swap from the player.
Check whether physics can also be applied to items, and what the corresponding performance hit would be.
Effects have to work in conjunction with animation and sound, so consult with these departments to ensure you’re all working to the same goal.
Posted on Wednesday, April 27th, 2011 at 3:36 pm under Guides, Tutorials. You can subscribe to comments. You can leave a comment, or trackback from your own site.
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