diff --git a/compare_med.glsl b/compare_med.glsl
deleted file mode 100644
index 2ab82d5..0000000
--- a/compare_med.glsl
+++ /dev/null
@@ -1,20 +0,0 @@
-// Compute the pixelwise diff between two textures.
-// Computes the diff for each color chanel separately (r, g, b).
-// Assumes both images are not transparent.
-
-// try isampler2D, ivec4 etc.? Probably not
-uniform vec2 size;
-uniform vec2 offs;
-uniform sampler2D base;
-uniform sampler2D curr;
-
-void main(void)
-{
-	vec2 pos = (gl_FragCoord.xy-offs)/size;
-	pos.y = 1.0 - pos.y;
-	vec4 color = texture2D(curr, pos);
-	vec4 basecolor = texture2D(base, pos);
-	color.xyz = color.xyz - basecolor.xyz;
-	color.xyz = (vec3(1.0, 1.0, 1.0) + color.xyz)/2.0;
-	gl_FragColor = color;
-}
diff --git a/fire.glsl b/fire.glsl
deleted file mode 100644
index 9f73a96..0000000
--- a/fire.glsl
+++ /dev/null
@@ -1,38 +0,0 @@
-#ifdef GL_ES
-precision mediump float;
-#endif
-
-uniform float time;
-uniform vec2 mouse;
-uniform vec2 resolution;
-
-float smove(float value)
-{
-	return (value + 1.0)/2.0;
-}
-
-float rand(vec2 co){
-	return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453);
-}
-
-void main(void)
-{
-	vec2 pos = gl_FragCoord.xy;  // rename for more meaty code
-	mouse.y = -mouse.y;
-// 	vec2 uv = pos/resolution.xy;
-// 	vec2 muv = mouse/resolution.xy;
-	
-	float scale = 100;
-	float modifier = sin(pos.x/scale + time)*sin(pos.y/scale - time);
-	modifier = smove(modifier);
-	
-	float dist = distance(gl_FragCoord.xy, mouse);
-	float radius = smove(sin(time))*50 + 100;
-	
-	float value = max(1 - dist/radius, 0);
-	value = value + modifier*0.3;
-	
-	value = value + (rand(pos.x*pos.y)-0.5)*0.03;
-	
-	gl_FragColor = vec4(value);
-}
diff --git a/src/Fitness.cpp b/src/Fitness.cpp
index f6e9319..8508cbc 100644
--- a/src/Fitness.cpp
+++ b/src/Fitness.cpp
@@ -4,9 +4,6 @@
 
 
 
-Fitness::Fitness() {}
-
-
 Fitness::Fitness(sf::Texture target, float scale)
 {
 	this->target = target;
@@ -36,7 +33,7 @@ bool Fitness::loadShader(std::string filename)
 }
 
 
-double Fitness::of(Chromosome chr)
+unsigned long long Fitness::of(Chromosome chr)
 {
 	// first, render a reduced, shaderized version to RenderTextures
 	this->tex.clear();
@@ -52,7 +49,7 @@ double Fitness::of(Chromosome chr)
 	// then, download the result as an image and add the pixels
 	sf::Image image = this->comp.getTexture().copyToImage();
 	sf::Vector2u size = image.getSize();
-	double fitness = 0;
+	unsigned long long fitness = 0;
 	for (unsigned int x=0; x<size.x; ++x) {
 		for (unsigned int y=0; y<size.y; ++y) {
 			sf::Color color = image.getPixel(x, y);
diff --git a/src/Fitness.hpp b/src/Fitness.hpp
index 9222712..d7a60b3 100644
--- a/src/Fitness.hpp
+++ b/src/Fitness.hpp
@@ -8,11 +8,10 @@
 class Fitness
 {
 public:
-	Fitness();
-	Fitness(sf::Texture target, float scale=0.5);
+	Fitness(sf::Texture target, float scale=1);
 	bool loadShader(std::string filename);
 	
-	double of(Chromosome chr);
+	unsigned long long of(Chromosome chr);
 	
 	sf::Texture target;      // base image to compare against
 	sf::RenderTexture tex;   // big RenderWindow containg the Chromosome to be evaluated