Expressing Sprite Animation Timing

Summary:

An idea

Expressing Sprite Animation Timing

hartnell 30 Aug 2007 15:49

Here's a thought, how about expressing sprite animation as a ratio? For example, take a sprite that is animated 4 frames per 2 loopins. Instead we could say it animates at 2/4 loopins. Diving 2 by 4 will also get you the decimal fraction you need to accomplish this. :)

What do you think?

—hartnell

Re: Expressing Sprite Animation Timing

u9 31 Aug 2007 01:24

this i didn't really understand. If a sprite is animated 4 frames per 2 loopins, then won't 2 of the frames never be seen? I mean if a sprite-animation cycles faster then the main loop then some frames will never be seen… or i misunderstood something?

Re: Expressing Sprite Animation Timing

hartnell 31 Aug 2007 05:07

Opps! 2 frames per 4 loopins. :) 2/4 loopins, or a decimal fraction of 0.5. —hartnell

Re: Expressing Sprite Animation Timing

u9 31 Aug 2007 10:17

yeah, i was beginning to think that you must have made a typo :)

Re: Expressing Sprite Animation Timing

Anonymous (211.28.241.x) 31 Aug 2007 06:06

Yeah, I guess that works.

Re: Expressing Sprite Animation Timing

u9 31 Aug 2007 10:31

Here's how i did the walking in Arabio World.

if character_left then
    frameIndex = 2
    frameOffset = round( sin( system.gettime / 75 ) )
elseif ...
    ...
end if

drawImage x, y, frameIndex + frameOffset

By adjusting the denominator (i think it is called) within the sin() function i can adjust the speed of the animation. frameOffset oscillates between -1 to 1 with time which was perfect because the animation was lined up like that so the animation sequence becomes: -1 0 1 0 -1 0 1 0 … This could be done the same way with loopins instead of time, so yeah, i'm sure it would work nicely.

Anyways, this brings me to another thought. When doing a game like Arabio World where the character walks. One could use the character's x location on the map to decide what frame to show. With some modulus and some fraction multiplication one can probably make the character's legs seem to be really connected with the ground, rather then the cartoony-unrealistic effect Arabio World now has, where the character just seems to "wheel-spin" across the surface as if he was the Road Runner. Hmm… Why am i talking about this now? :S hehe oh well, over and out

Last edited on 31 Aug 2007 10:32 by u9 Show more