#tweetcoding Part 4 – Bubbles, Sineribbon & Feedback Vortex

Number eight is Bubbles. Of my #tweetcoding entries, this is possibly my favourite. It’s nothing special technically, but I love recreating natural/physical phenomena, and to do so in 140 characters is even better. I was inspired when staring into a glass of beer – unfortunately I was unable to implement a nice amber colour within the constraints.

Love the pseudo-3D parallax effect, random motion, differing colours & transparency. The only thing I would improve is the visual appearance of the bubbles – it’d be nice to add some shading. Otherwise I’m pretty happy with this one.

bubbles

g.clear();for(i=j=550;i--;){!o[i]?o[i]={x:r()*j,y:r()*j,s:r()*9}:p=o[i];with(p){ls(s,j+i,.2);mt(x,y);lt(x+=r()*4-2,y-=r()*p.s);if(y<0)y=j}}

Nine is Sineribbon. This was an attempt to recreate one of my favourite effects, seen here in another classic PC demo – X14 by Orange from 1995. Skip to the 2:50 mark to see the effect or, better still, watch the whole thing. Unfortunately for me, the character constraint was too limiting, so I ended up with what you see here. I might try and revisit this one though.

sineribbon

q=200;g.clear();if(!o.a)o.a=o.b=1;with(o){a+=.03;b-=.07;for(j=550;j--;){p=s(j/q+s(a+j/q)+s(b+j/179))*q/2;ls(1,p+q/2);mt(j,q-p);lt(j,q+p)}}

Ten – Feedback Vortex. Video Feedback goes all the way back to the advent of analogue video back in 1956, although it wasn’t used purposefully until the 1960s and didn’t really take off until decades later. Creating this effect in Flash is simple – just add a bitmap to the stage and, each frame, copy the entire stage into the bitmap, with input image, noise or colour around the bitmap to start the effect off. Over multiple frames, this generates copies of the input image – each one nested within the last. By adjusting the scale and rotation of the bitmap, the copies can be made to spiral, or zoom in and out.

My favourite demoscene example is again from X14 by Orange, at the 2:40 mark.

Credit is due to Quasimondo for the first #tweetcoding entry to use bitmap feedback, but I’m no stranger to the effect either, having implemented it in Director back in the day, and again in Flash when the FP8 beta was released.

feedbackvortex

q=550;g.clear();if(!o.b)addChild(o.c=new Bitmap(o.b=new BitmapData(q,q))).rotation=2;o.c.z=s(i+=.03)*70+30;ls(9,i*q);lt(q,0);o.b.draw(this);

One Comment

#tweetcoding « Pixelero  on February 27th, 2009

[...] don’t forget to also check Quasimondo’s or Rob Muller’s entries – among all the other stuff of course. Possibly related posts: (automatically [...]

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