GLSL Effects used by Drone Tank Arena ( http://dta.greweb.fr/ )

perturbation.frag

uniform float p;
uniform float amount;
uniform float seed;
uniform float lines;
uniform sampler2D tDiffuse;
varying vec2 vUv;

float rand(vec2 co){
    return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453);
}
void main( void ) {
vec2 position = vUv;
float y = floor(lines*position.y)/lines;
float disf = 0.01*(cos(position.y*130.+p*10.)+sin(position.y*183.+p*80.));
float parity = 0.; if(mod(y*lines, 2.)>0.5) parity=1.; else parity=-1.;
float a = smoothstep(0., 1.0, p);
position.x = amount*a*(y*0.3+disf)+position.x+
        amount*0.5*parity*smoothstep(0.6, 0.65, p)*(sin(position.y*(12.+40.*seed))+smoothstep(0.64, 0.65, p));
vec4 colorInput = texture2D( tDiffuse, position );
gl_FragColor = colorInput;
}

radionoise.frag

uniform float amount;
uniform float time;
uniform float width;
uniform float height;
uniform sampler2D tDiffuse;
varying vec2 vUv;

float rand(vec2 co){
    return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453);
}
void main( void ) {
  vec2 position = vUv;
vec4 colorInput = texture2D( tDiffuse, vUv );

vec2 roundPos = vec2(floor(width*position.x)/width,
                     floor(height*position.y)/height);

vec3 color = vec3(0.1, 1.0, 0.1)*vec3(rand(roundPos+time/1000.));

float d2 = 1.;

if (cos(position.y*40.+time*3.)<-0.95)
  color += vec3(0,0.07,0);

if (0.99999+cos(position.y*1.+time*0.8)<0.)
  color += vec3(0,0.15,0);

  gl_FragColor = colorInput*(1.0-amount)+amount*vec4( color, 1. );
}

MIT license gre/dta@cd96d31