diff --git a/Anim.c b/Anim.c
new file mode 100644
index 0000000..19118e8
--- /dev/null
+++ b/Anim.c
@@ -0,0 +1,3 @@
+
+#include "Anim.h"
+
diff --git a/Anim.h b/Anim.h
new file mode 100644
index 0000000..73cc821
--- /dev/null
+++ b/Anim.h
@@ -0,0 +1,5 @@
+#ifndef _ANIM_H_
+#define _ANIM_H_
+
+
+#endif
diff --git a/Draw.c b/Draw.c
index edcfbf3..60132df 100644
--- a/Draw.c
+++ b/Draw.c
@@ -5,6 +5,7 @@
 #include <SDL/SDL.h>
 
 #include "Time.h"
+#include "Util.h"
 #include "Draw.h"
 #include "Input.h"
 #include "Audio.h"
@@ -149,29 +150,79 @@ void Draw_Clean(
 		 SDL_MapRGB(_screen->format, r, g, b));
 }
 
+////////////////////////////////////////////////
+// DrawImage //
+///////////////
+// Image container.
+typedef struct Tag_DrawImage {
+	SDL_Surface *surf;
+	int x,y;
+} DrawImage;
+
 
 /////////////////////////////
 // Draw_LoadImage
 //
 // Loads a image, giving a reference.
 DrawImg Draw_LoadImage(char *filename){
-	SDL_Surface *img;
+	DrawImage *image;
+	SDL_Surface *surf;
 
 	// Load the BMP as a surface
-	img=SDL_LoadBMP(filename);
-	if(img == NULL){
+	surf=SDL_LoadBMP(filename);
+	if(surf == NULL){
 		printf("Draw_LoadImage: Failure Loading image: %s\n",filename);
 		printf("Draw_LoadImage: SDL Error: %s\n",SDL_GetError());
 		return(NULL);
 	}
 
 	// FIX: Setting up the alpha channel.
-	if(img->format->BytesPerPixel==4){
-		img->format->Amask=0xFF000000;
-		img->format->Ashift=24;
+	if(surf->format->BytesPerPixel==4){
+		surf->format->Amask=0xFF000000;
+		surf->format->Ashift=24;
 	}
 
-	return((DrawImg *)img);
+	// Create the image container
+	image=malloc(sizeof(DrawImage));
+	image->surf=surf;
+	image->x=0;
+	image->y=0;
+
+	return((DrawImg)image);
+}
+
+
+/////////////////////////////
+// Draw_GetSize
+//
+// Gets the image size.
+void Draw_GetSize(DrawImg img,int *w,int *h){
+	DrawImage *image=img;
+
+	// Gets the image size
+	*w=image->surf->w;
+	*h=image->surf->h;
+}
+
+
+/////////////////////////////
+// Draw_SetOffset
+// Draw_GetOffset
+//
+// Sets and Gets the image offset.
+void Draw_SetOffset(DrawImg img,int  x,int  y){
+	DrawImage *image=img;
+
+	// Sets the image offset
+	image->x=x;
+	image->y=y;
+}
+void Draw_GetOffset(DrawImg img,int *x,int *y){
+	DrawImage *image=img;
+
+	// Gets the image offset
+	*x=image->x;
+	*y=image->y;
 }
 
 
@@ -184,14 +235,11 @@ void Draw_ImgSetKeyCol(DrawImg img,
 	unsigned char g,
 	unsigned char b)
 {
-	SDL_Surface *surf;
-	if(!img)
-		return;
+	DrawImage *image=img;
 
 	// Set the color key for the surface
-	surf=(SDL_Surface *)img;
-	SDL_SetColorKey(surf, SDL_SRCCOLORKEY,
-		SDL_MapRGB(surf->format, r, g, b));
+	SDL_SetColorKey(image->surf, SDL_SRCCOLORKEY,
+		SDL_MapRGB(image->surf->format, r, g, b));
 }
 
 
@@ -200,58 +248,32 @@ void Draw_ImgSetKeyCol(DrawImg img,
 //
 // Setting the image alpha.
 void Draw_ImgSetAlpha(DrawImg img, unsigned char a){
-	SDL_Surface *surf;
-	if(!img)
-		return;
+	DrawImage *image=img;
 
 	// Set the alpha for the surface
-	surf=(SDL_Surface *)img;
-	SDL_SetAlpha(surf, SDL_SRCALPHA, a);
+	SDL_SetAlpha(image->surf, SDL_SRCALPHA, a);
 }
 
 
 /////////////////////////////
 // Draw_DrawImg
-// Draw_DrawImgCenter
 //
-// Draws an image. And a centered variant
+// Draws an image.
 void Draw_DrawImg(DrawImg img,int x,int y){
-	SDL_Surface *surf;
+	DrawImage *image=img;
 	SDL_Rect orig;
 	SDL_Rect dest;
-	if(!img)
-		return;
 
 	// Prepare the rects
-	surf=(SDL_Surface *)img;
 	orig.x=0;
 	orig.y=0;
-	dest.x=x;
-	dest.y=y;
-	orig.w=dest.w=surf->w;
-	orig.h=dest.h=surf->h;
+	dest.x=x+image->x;
+	dest.y=y+image->y;
+	orig.w=dest.w=image->surf->w;
+	orig.h=dest.h=image->surf->h;
 
 	// Blit the surface on the screen
-	SDL_BlitSurface(surf,&orig,_screen,&dest);
-}
-void Draw_DrawImgCenter(DrawImg img,int x,int y){
-	SDL_Surface *surf;
-	SDL_Rect orig;
-	SDL_Rect dest;
-	if(!img)
-		return;
-
-	// Prepare the rects
-	surf=(SDL_Surface *)img;
-	orig.x=0;
-	orig.y=0;
-	dest.x=x-(surf->w/2);
-	dest.y=y-(surf->h/2);
-	orig.w=dest.w=surf->w;
-	orig.h=dest.h=surf->h;
-
-	// Blit the surface on the screen
-	SDL_BlitSurface(surf,&orig,_screen,&dest);
+	SDL_BlitSurface(image->surf,&orig,_screen,&dest);
 }
 
 
@@ -324,8 +346,6 @@ void Draw_DrawText(DrawFnt f,char *text,int x,int y){
 	SDL_Rect orig;
 	SDL_Rect dest;
 	char *ptr;
-	if(!f)
-		return;
 
 	// Prepare the rects
 	orig.w=dest.w=font->w;
diff --git a/Draw.h b/Draw.h
index 22a52da..cb34ad7 100644
--- a/Draw.h
+++ b/Draw.h
@@ -40,6 +40,22 @@ typedef void *DrawImg;
 DrawImg Draw_LoadImage(char *filename);
 
 
+/////////////////////////////
+// Draw_GetSize
+//
+// Gets the image size.
+void Draw_GetSize(DrawImg img,int *w,int *h);
+
+
+/////////////////////////////
+// Draw_SetOffset
+// Draw_GetOffset
+//
+// Sets and Gets the image offset.
+void Draw_SetOffset(DrawImg img,int  x,int  y);
+void Draw_GetOffset(DrawImg img,int *x,int *y);
+
+
 /////////////////////////////
 // Draw_ImgSetKeyCol
 //
@@ -59,11 +75,9 @@ void Draw_ImgSetAlpha(DrawImg img, unsigned char a);
 
 /////////////////////////////
 // Draw_DrawImg
-// Draw_DrawImgCenter
 //
-// Draws an image. And a centered variant
+// Draws an image.
 void Draw_DrawImg(DrawImg img,int x,int y);
-void Draw_DrawImgCenter(DrawImg img,int x,int y);
 
 
 ////////////////////////////////////////////////
diff --git a/Entity.c b/Entity.c
index b519d82..5b9fc3b 100644
--- a/Entity.c
+++ b/Entity.c
@@ -1,37 +1,225 @@
-#ifndef _ENTITY_H_
-#define _ENTITY_H_
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
 
+#include "Util.h"
+#include "Draw.h"
 
-////////////////////////////////////////////////
-// Entity //
-////////////
-// Reference to an entity.
-typedef void *Entity;
+#include "Entity.h"
 
 
 /////////////////////////////
-// Entity_Create
+// Entity_New
 //
-// Creates an entity.
-Entity Entity_Create(
-	int x,int y,
-	void (*process)(Entity ent,void *data),
-	void *data);
+//
+Entity *Entity_New(){
+	Entity *e;
+
+	e=malloc(sizeof(Entity));
+
+	e->type=0;
+	vec2_set(e->pos,0.0f,0.0f);
+
+	vec2_set(e->vel,0.0f,0.0f);
+	e->radius=1.0f;
+	e->mass=1.0f;
+	e->elast=0.0f;
+	e->fric_static=1.0f;
+	e->fric_dynamic=0.0f;
+
+	e->img=NULL;
+
+	e->proc=NULL;
+	e->postproc=NULL;
+
+	return(e);
+}
 
 
 /////////////////////////////
-// Entity_Create
+// Entity_Destroy
 //
-// Creates an entity.
+//
+void Entity_Destroy(Entity *e){
+	free(e);
+}
+
 
 /////////////////////////////
-// Entity_CreateClass
+// Entity_Copy
 //
-// Initializes the game.
-void Entity_CreateClass(char *name,
-	void *(*createdata)(),
-	void (*process)(Entity ent,void *data));
+//
+Entity *Entity_Copy(Entity *e){
+	Entity *n;
+
+	n=Entity_New();
+
+	n->type=e->type;
+	vec2_set(n->pos,e->pos[0],e->pos[1]);
+
+	vec2_set(n->vel,e->vel[0],e->vel[1]);
+	n->radius=e->radius;
+	n->mass=e->mass;
+	n->elast=e->elast;
+	n->fric_static=e->fric_static;
+	n->fric_dynamic=e->fric_dynamic;
+
+	n->img=e->img;
+
+	n->proc=e->proc;
+	n->postproc=e->postproc;
+
+	return(n);
+}
 
 
+/////////////////////////////
+// Entity_Draw
+//
+//
+void Entity_Draw(Entity *e){
+	if(e->img)
+		Draw_DrawImg(e->img,e->pos[0],e->pos[1]);
+}
 
-#endif
+
+/////////////////////////////
+// Entity_Process
+//
+//
+void Entity_Process(Entity *b){
+
+	// Launch method
+	if(b->proc){
+		b->proc(b);
+	}
+}
+
+
+/////////////////////////////
+// Entity_PostProcess
+//
+//
+void Entity_PostProcess(Entity *e){
+	float qlen,len;
+
+	// Launch method
+	if(e->postproc){
+		e->postproc(e);
+	}
+
+	// Determine if there is movement
+	qlen=vec2_dot(e->vel,e->vel);
+	if(qlen>0.0f){
+
+		// Update position
+		vec2_plus(e->pos,e->pos,e->vel);
+
+		// Aply friction
+		len=sqrtf(qlen);
+		if(len<e->fric_static){
+			// Stopped by static friction
+			vec2_set(e->vel,0,0);
+		}else{
+			// Aply dynamic friction
+			vec2_scale(e->vel,e->vel,
+				1.0f-(e->fric_dynamic+(e->fric_static/len)));
+		}
+	}
+}
+
+
+/////////////////////////////
+// Entity_Collide
+//
+//
+int Entity_Collide(Entity *b1,Entity *b2){
+	float t;
+	vec2 n;
+	vec2 cir1[2];
+	vec2 cir1i,cir2i;
+	Entity *b_aux;
+
+	// FIX: Swap colision order based on moving object
+	if(vec2_dot(b1->vel,b1->vel)<vec2_dot(b2->vel,b2->vel)){
+		b_aux=b1;
+		b1=b2;
+		b2=b_aux;
+	}
+
+	// Prepare testing vectors
+	vec2_copy(cir1[0],b1->pos);
+	vec2_plus(cir1[1],b1->pos,b1->vel);
+	vec2_minus(cir1[1],cir1[1],b2->vel);
+
+	if(Colision_CircleCircle(cir1,b1->radius,b2->pos,b2->radius,&t,n)){
+		float moment;
+		vec2 temp,temp2;
+		float elast;
+
+		// Collision response
+
+		if(b1->mass>0.0f && b2->mass>0.0f){
+			// Calculate elasticity
+			elast=(b1->mass*b1->elast+b2->mass*b2->elast)/
+				(b1->mass+b2->mass);
+
+			// Collision between two massed balls
+			moment=((1.0f+elast)*b1->mass*b2->mass*
+						(vec2_dot(b1->vel,n)+vec2_dot(b2->vel,n)))
+					/(b1->mass+b2->mass);
+			vec2_scale(temp,n,moment/b1->mass);
+			vec2_minus(b1->vel,b1->vel,temp);
+			vec2_scale(temp,n,moment/b2->mass);
+			vec2_plus(b2->vel,b2->vel,temp);
+		}else
+		if(b1->mass>0.0f && b2->mass<=0.0f){
+			// Collision between a massed ball and a fixed ball
+			moment=(1.0f+b1->elast)*
+						(vec2_dot(b1->vel,n));
+			vec2_scale(temp,n,moment);
+			vec2_minus(b1->vel,b1->vel,temp);
+		}else
+		if(b1->mass<=0.0f && b2->mass>0.0f){
+			// Collision between a massed ball and a fixed ball
+			// (imposible, but better safe)
+			moment=(1.0f+b2->elast)*
+						(vec2_dot(b2->vel,n));
+			vec2_scale(temp,n,moment);
+			vec2_plus(b2->vel,b2->vel,temp);
+		}else{
+			// Collision between 2 fixed balls
+			// (imposible, but better safe)
+			vec2_set(b1->vel,0,0);
+			vec2_set(b2->vel,0,0);
+		}
+		return(1);
+	}
+	return(0);
+}
+
+
+/////////////////////////////
+// Entity_AddVelLimit
+//
+//
+void Entity_AddVelLimit(Entity *e,vec2 vel,float limit){
+	float vlen_orig,vlen;
+	vec2 dir,vel_temp;
+
+	// Normalize vel getting vel
+	vlen_orig=sqrtf(vec2_dot(vel,vel));
+	vec2_scale(dir,vel,1.0f/vlen_orig);
+
+	// Limit velocity
+	vlen=vec2_dot(e->vel,dir);
+	if(vlen<limit){
+		vlen=limit-vlen;
+		if(vlen>vlen_orig){
+			vlen=vlen_orig;
+		}
+		vec2_scale(vel_temp,dir,vlen);
+		vec2_plus(e->vel,e->vel,vel_temp);
+	}
+
+}
diff --git a/Entity.h b/Entity.h
index 8d5c1ad..264f3e3 100644
--- a/Entity.h
+++ b/Entity.h
@@ -1,6 +1,87 @@
 #ifndef _ENTITY_H_
 #define _ENTITY_H_
 
+#include "Util.h"
+#include "Draw.h"
+
+
+////////////////////////////////////////////////
+// Entity //
+////////////
+//
+typedef struct Tag_Entity{
+
+	int type;
+	vec2 pos;
+
+	vec2 vel;
+	vec2 bod_offset;
+	float radius;
+	float mass;
+	float elast;
+	float fric_static;
+	float fric_dynamic;
+
+	DrawImg img;
+
+	void (*proc)(struct Tag_Entity *ent);
+	void (*postproc)(struct Tag_Entity *ent);
+} Entity;
+
+
+/////////////////////////////
+// Entity_New
+//
+//
+Entity *Entity_New();
+
+
+/////////////////////////////
+// Entity_Destroy
+//
+//
+void Entity_Destroy(Entity *e);
+
+
+/////////////////////////////
+// Entity_Copy
+//
+//
+Entity *Entity_Copy(Entity *e);
+
+
+/////////////////////////////
+// Entity_Draw
+//
+//
+void Entity_Draw(Entity *e);
+
+
+/////////////////////////////
+// Entity_Process
+//
+//
+void Entity_Process(Entity *e);
+
+/////////////////////////////
+// Entity_PostProcess
+//
+//
+void Entity_PostProcess(Entity *e);
+
+
+/////////////////////////////
+// Entity_Collide
+//
+//
+int Entity_Collide(Entity *b1,Entity *b2);
+
+
+/////////////////////////////
+// Entity_AddVelLimit
+//
+//
+void Entity_AddVelLimit(Entity *e,vec2 vel,float limit);
 
 
 #endif
diff --git a/GameLib.c b/GameLib.c
index d9ef72c..484cc2e 100644
--- a/GameLib.c
+++ b/GameLib.c
@@ -1,11 +1,23 @@
 #include <SDL/SDL.h>
 
+#include "Time.h"
+#include "Util.h"
 #include "Draw.h"
 #include "Input.h"
 #include "Audio.h"
+#include "Anim.h"
 #include "Entity.h"
+
 #include "GameLib.h"
 
+// Globals
+int _running;
+Entity **_entity=NULL;
+int _n_entities=0;
+int _n_entities_res=0;
+void (*_gameproc)()=NULL;
+void (*_gamepostproc)()=NULL;
+
 
 /////////////////////////////
 // GameLib_Init
@@ -23,4 +35,159 @@ int GameLib_Init(int w,int h,char *title,int fps){
 }
 
 
+/////////////////////////////
+// GameLib_AddEntity
+//
+// Adds an entity to the game.
+void GameLib_AddEntity(Entity *e){
+	if(_n_entities>=_n_entities_res){
+		Entity **entity_aux;
+		int i;
 
+		// Grow the array
+		if(_n_entities_res==0)
+			_n_entities_res=32;
+		else
+			_n_entities_res*=2;
+		entity_aux=malloc(sizeof(Entity *)*_n_entities_res);
+		for(i=0;i<_n_entities;i++)
+			entity_aux[i]=_entity[i];
+		if(_entity)
+			free(_entity);
+		_entity=entity_aux;
+	}
+
+	// Add the entity
+	_entity[_n_entities]=e;
+	_n_entities++;
+}
+
+
+/////////////////////////////
+// GameLib_UnrefEntity
+//
+// removes the reference to the entity.
+int GameLib_UnrefEntity(Entity *e){
+	int i;
+	for(i=0;i<_n_entities;i++){
+		if(e==_entity[i]){
+			_entity[i]=NULL;
+			return(1);
+		}
+	}
+	return(0);
+}
+
+
+/////////////////////////////
+// GameLib_DelEntity
+//
+// Adds an entity to the game.
+int GameLib_DelEntity(Entity *e){
+	if(!GameLib_UnrefEntity(e)){
+		return(0);
+	}
+	Entity_Destroy(e);
+	return(1);
+}
+
+
+/////////////////////////////
+// GameLib_ProcLoop
+//
+// Process the loop.
+int GameLib_ProcLoop(){
+	int i,j;
+	int repeat,count;
+
+	// Launch the method
+	if(_gameproc){
+		_gameproc();
+	}
+
+	// Process entities
+	for(i=0;i<_n_entities;i++){
+		if(!_entity[i])
+			continue;
+		Entity_Process(_entity[i]);
+	}
+
+	// Process colisions between entities
+	count=0;
+	do{
+		repeat=0;
+		for(i=0;i<_n_entities-1;i++){
+			for(j=i+1;j<_n_entities;j++){
+				if(!_entity[i] || !_entity[j])
+					continue;
+				if(Entity_Collide(_entity[i],_entity[j])){
+					repeat=1;
+				}
+			}
+		}
+		count++;
+	}while(repeat && count<10);
+
+	// Stop remaining collisions
+	for(i=0;i<_n_entities-1;i++){
+		for(j=i+1;j<_n_entities;j++){
+			if(!_entity[i] || !_entity[j])
+				continue;
+			if(Entity_Collide(_entity[i],_entity[j])){
+				vec2_set(_entity[i]->vel,0,0);
+				vec2_set(_entity[j]->vel,0,0);
+			}
+		}
+	}
+
+	// PostProcess and draw entities
+	for(i=0;i<_n_entities;i++){
+		if(!_entity[i])
+			continue;
+		Entity_PostProcess(_entity[i]);
+		Entity_Draw(_entity[i]);
+	}
+
+	// Compactate
+	j=0;
+	for(i=0;i<_n_entities;i++){
+		if(!_entity[i])
+			continue;
+		if(i>j)
+			_entity[j]=_entity[i];
+		j++;
+	}
+	_n_entities=j;
+
+	// Launch the method
+	if(_gamepostproc){
+		_gamepostproc();
+	}
+
+	return(_running);
+}
+
+
+/////////////////////////////
+// GameLib_Loop
+//
+// Loops the game.
+void GameLib_Loop(
+	void (*gameproc)(),
+	void (*gamepostproc)())
+{
+	_running=1;
+
+	_gameproc=gameproc;
+	_gamepostproc=gamepostproc;
+	Draw_Loop(GameLib_ProcLoop);
+}
+
+
+/////////////////////////////
+// GameLib_BreakLoop
+//
+// Breaks the game loop.
+void GameLib_BreakLoop(){
+	_running=0;
+}
diff --git a/GameLib.h b/GameLib.h
index f208ca0..e472fb8 100644
--- a/GameLib.h
+++ b/GameLib.h
@@ -1,9 +1,12 @@
 #ifndef _GAMELIB_H_
 #define _GAMELIB_H_
 
+#include "Time.h"
+#include "Util.h"
 #include "Draw.h"
 #include "Input.h"
 #include "Audio.h"
+#include "Anim.h"
 #include "Entity.h"
 
 
@@ -14,11 +17,34 @@
 int GameLib_Init(int w,int h,char *title,int fps);
 
 
+/////////////////////////////
+// GameLib_AddEntity
+//
+// Adds an entity to the game.
+void GameLib_AddEntity(Entity *e);
+
+
+/////////////////////////////
+// GameLib_UnrefEntity
+//
+// removes the reference to the entity.
+int GameLib_UnrefEntity(Entity *e);
+
+
+/////////////////////////////
+// GameLib_DelEntity
+//
+// Adds an entity to the game.
+int GameLib_DelEntity(Entity *e);
+
+
 /////////////////////////////
 // GameLib_Loop
 //
 // Loops the game.
-void GameLib_Loop();
+void GameLib_Loop(
+	void (*gameproc)(),
+	void (*gamepostproc)());
 
 
 /////////////////////////////
diff --git a/Input.c b/Input.c
index 06a8eac..dd7f3b7 100644
--- a/Input.c
+++ b/Input.c
@@ -1,5 +1,7 @@
+#include <math.h>
 #include <SDL/SDL.h>
 
+#include "Util.h"
 #include "Input.h"
 
 
@@ -66,3 +68,34 @@ void Input_SetKey(InputKey key,int status){
 InputKeyStatus Input_GetKey(InputKey key){
 	return(_keys[key]);
 }
+
+
+/////////////////////////////
+// Input_GetDir
+//
+// Reports the direction of the dpad.
+int Input_GetDir(vec2 dir){
+	float vlen;
+
+	vec2_set(dir,0.0f,0.0f);
+	if(Input_GetKey(InputKey_Up) ){
+		dir[1]-=1.0f;
+	}
+	if(Input_GetKey(InputKey_Down) ){
+		dir[1]+=1.0f;
+	}
+	if(Input_GetKey(InputKey_Left) ){
+		dir[0]-=1.0f;
+	}
+	if(Input_GetKey(InputKey_Right) ){
+		dir[0]+=1.0f;
+	}
+	vlen=vec2_dot(dir,dir);
+	if(vlen>0.0f){
+		vlen=sqrtf(vlen);
+		vec2_scale(dir,dir,1.0f/vlen);
+		return(1);
+	}else{
+		return(0);
+	}
+}
diff --git a/Input.h b/Input.h
index dfaf10f..90d8b07 100644
--- a/Input.h
+++ b/Input.h
@@ -1,6 +1,8 @@
 #ifndef _INPUT_H_
 #define _INPUT_H_
 
+#include "Util.h"
+
 
 /////////////////////////////
 // Input_Init
@@ -57,5 +59,11 @@ typedef enum {
 InputKeyStatus Input_GetKey(InputKey key);
 
 
+/////////////////////////////
+// Input_GetDir
+//
+// Reports the direction of the dpad.
+int Input_GetDir(vec2 dir);
+
 
 #endif
diff --git a/Makefile b/Makefile
index 17e6917..c81f8f4 100644
--- a/Makefile
+++ b/Makefile
@@ -14,7 +14,7 @@ endif # windir
 
 
 ifeq ($(TARGET_ARCH),mingw)
-	include Makefile.mingw
+	include Makefile.win32
 else
 ifeq ($(TARGET_ARCH),linux)
 	include Makefile.linux
diff --git a/Makefile.common b/Makefile.common
index e73611d..b3e72c4 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -1,15 +1,20 @@
 HEADS= \
 	Time.h \
+	Util.h \
 	Draw.h \
 	Input.h \
 	Audio.h \
+	Anim.h \
 	Entity.h \
 	GameLib.h
+
 OBJS= \
 	$(BUILDDIR)/Time.o \
+	$(BUILDDIR)/Util.o \
 	$(BUILDDIR)/Draw.o \
 	$(BUILDDIR)/Input.o \
 	$(BUILDDIR)/Audio.o \
+	$(BUILDDIR)/Anim.o \
 	$(BUILDDIR)/Entity.o \
 	$(BUILDDIR)/GameLib.o \
 	$(BUILDDIR)/main.o
@@ -25,6 +30,9 @@ $(BUILDDIR):
 $(BUILDDIR)/Time.o: Time.c $(HEADS)
 	$(CC) -c Time.c -o $(BUILDDIR)/Time.o $(CFLAGS)
 
+$(BUILDDIR)/Util.o: Util.c $(HEADS)
+	$(CC) -c Util.c -o $(BUILDDIR)/Util.o $(CFLAGS)
+
 $(BUILDDIR)/Draw.o: Draw.c $(HEADS)
 	$(CC) -c Draw.c -o $(BUILDDIR)/Draw.o $(CFLAGS)
 
@@ -37,6 +45,9 @@ $(BUILDDIR)/Audio.o: Audio.c $(HEADS)
 $(BUILDDIR)/Entity.o: Entity.c $(HEADS)
 	$(CC) -c Entity.c -o $(BUILDDIR)/Entity.o $(CFLAGS)
 
+$(BUILDDIR)/Anim.o: Anim.c $(HEADS)
+	$(CC) -c Anim.c -o $(BUILDDIR)/Anim.o $(CFLAGS)
+
 $(BUILDDIR)/GameLib.o: GameLib.c $(HEADS)
 	$(CC) -c GameLib.c -o $(BUILDDIR)/GameLib.o $(CFLAGS)
 
diff --git a/Makefile.linux b/Makefile.linux
index 4f167ec..17fba89 100644
--- a/Makefile.linux
+++ b/Makefile.linux
@@ -1,4 +1,4 @@
-LIBS= -lSDL -lpthread -L/usr/X11R6/lib -L/usr/lib
+LIBS= -lSDL -lpthread -L/usr/X11R6/lib -L/usr/lib -lm
 CFLAGS= -Wall -g -I/usr/include/ -I/usr/include/SDL/ -I/usr/X11R6/include/
 CC=gcc
 RM=rm -rf
diff --git a/Makefile.win32 b/Makefile.win32
new file mode 100644
index 0000000..7116ed9
--- /dev/null
+++ b/Makefile.win32
@@ -0,0 +1,11 @@
+LIBS=-I/mingw/include/SDL -D_GNU_SOURCE=1 -Dmain=SDL_main
+CFLAGS= -L/mingw/lib -lmingw32 -lSDLmain -lSDL -mwindows -g
+CC=gcc
+RM=rm -rf
+
+RESULT=game.exe
+BUILDDIR=build-mingw
+
+include Makefile.common
+
+
diff --git a/Util.c b/Util.c
new file mode 100644
index 0000000..e726273
--- /dev/null
+++ b/Util.c
@@ -0,0 +1,93 @@
+#include <math.h>
+
+#include "Util.h"
+
+
+/////////////////////////////
+// SolveQuadratic
+//
+// Solves a Quadratic equation using a, b and c coeficients.
+int SolveQuadratic(float a,float b,float c,float *Rmin,float *Rmax){
+	float root;
+	float divisor;
+	float b2;
+	b2=b*b;
+	root=b2-4.0*a*c;
+	if(root<0){
+		// Complex
+		return(0);
+	}
+	divisor=(2.0*a);
+	if(fabs(divisor)==0.0f){
+		// +inf -inf
+		return(0);
+	}
+	root=sqrtf(root);
+	Rmin[0]=(float)((-b-root)/divisor);
+	Rmax[0]=(float)((-b+root)/divisor);
+	return(1);
+}
+
+
+/////////////////////////////
+// Intersec_RayUnitCircle
+//
+// Intersection between a ray and a Unit Circle.
+int Intersec_RayUnitCircle(vec2 orig,vec2 vel,vec2 center,float *t){
+	float a,b,c;
+	float Rmin,Rmax;
+	vec2 temp;
+
+	// Solve as a unit circle
+	a=vec2_dot(vel,vel);
+	if(fabs(a)<0.000001f){
+		return(0);
+	}
+	vec2_minus(temp,orig,center);
+	b=2.0f*vec2_dot(temp,vel);
+	c=vec2_dot(temp,temp)-1.0f;
+	if(SolveQuadratic(a,b,c,&Rmin,&Rmax)){
+		if(Rmin>=-0.0001f && Rmin<Rmax && Rmin<=1.0f){
+			*t=Rmin;
+			return(1);
+		}
+		if(Rmax>=-0.0001f && Rmin>Rmax && Rmax<=1.0f){
+			*t=Rmax;
+			return(1);
+		}
+	}
+	return(0);
+}
+
+
+/////////////////////////////
+// Colision_CircleCircle
+//
+// Colision point of a circle against another circle.
+int Colision_CircleCircle(
+	vec2 cir1[2],float rad1,
+	vec2 cir2,float rad2,
+	float *t,vec2 n)
+{
+	vec2 vel,orig,cen,temp;
+	float rads,invrads;
+
+	// Convert to a unit circle vs ray
+	rads=rad1+rad2;
+	invrads=1.0f/rads;
+	vec2_minus(vel,cir1[1],cir1[0]);
+	vec2_scale(vel,vel,invrads);
+	vec2_scale(orig,cir1[0],invrads);
+	vec2_scale(cen,cir2,invrads);
+	if(Intersec_RayUnitCircle(orig,vel,cen,t)){
+		// Calculate n
+		vec2_minus(vel,cir1[1],cir1[0]);
+		vec2_scale(temp,vel,*t);
+		vec2_plus(temp,cir1[0],temp);
+		vec2_minus(temp,cir2,temp);
+		vec2_scale(n,temp,1.0f/rads);
+		return(1);
+	}
+	return(0);
+}
+
diff --git a/Util.h b/Util.h
new file mode 100644
index 0000000..bc89c46
--- /dev/null
+++ b/Util.h
@@ -0,0 +1,44 @@
+#ifndef _UTIL_H_
+#define _UTIL_H_
+
+
+/////////////////////////////
+// SolveQuadratic
+//
+// Solves a Quadratic equation using a, b and c coeficients.
+int SolveQuadratic(float a,float b,float c,float *Rmin,float *Rmax);
+
+
+////////////////////////////////////////////////
+// vec2 //
+//////////
+// A 2D vector.
+typedef float vec2[2];
+#define vec2_set(v,x,y) (v)[0]=(x);(v)[1]=(y);
+#define vec2_copy(v1,v2) (v1)[0]=(v2)[0];(v1)[1]=(v2)[1];
+#define vec2_plus(v,v1,v2) (v)[0]=(v1)[0]+(v2)[0];(v)[1]=(v1)[1]+(v2)[1];
+#define vec2_minus(v,v1,v2) (v)[0]=(v1)[0]-(v2)[0];(v)[1]=(v1)[1]-(v2)[1];
+#define vec2_scale(v,v1,s) (v)[0]=(v1)[0]*(s);(v)[1]=(v1)[1]*(s);
+#define vec2_dot(v1,v2) ((v1)[0]*(v2)[0]+(v1)[1]*(v2)[1])
+
+
+/////////////////////////////
+// Intersec_RayUnitCircle
+//
+// Intersection between a ray and a Unit Circle.
+int Intersec_RayUnitCircle(vec2 orig,vec2 vel,vec2 center,float *t);
+
+
+
+
+/////////////////////////////
+// Intersect_CircleCircle
+//
+// Colision point of a circle against another circle.
+int Colision_CircleCircle(
+	vec2 ca[2],float ra,
+	vec2 cb,float rb,
+	float *t,vec2 n);
+
+
+#endif
diff --git a/data/agua.bmp b/data/agua.bmp
deleted file mode 100644
index 6960a10..0000000
Binary files a/data/agua.bmp and /dev/null differ
diff --git a/data/bisho.bmp b/data/bisho.bmp
deleted file mode 100644
index 6bc3171..0000000
Binary files a/data/bisho.bmp and /dev/null differ
diff --git a/data/bisho2_alpha.bmp b/data/bisho2_alpha.bmp
new file mode 100644
index 0000000..1525aea
Binary files /dev/null and b/data/bisho2_alpha.bmp differ
diff --git a/data/bloque.bmp b/data/bloque.bmp
new file mode 100644
index 0000000..2973088
Binary files /dev/null and b/data/bloque.bmp differ
diff --git a/data/tierra.bmp b/data/tierra.bmp
deleted file mode 100644
index b0bbfae..0000000
Binary files a/data/tierra.bmp and /dev/null differ
diff --git a/data/tile0000.bmp b/data/tile0000.bmp
deleted file mode 100644
index 8529e2f..0000000
Binary files a/data/tile0000.bmp and /dev/null differ
diff --git a/data/tile0001.bmp b/data/tile0001.bmp
deleted file mode 100644
index aca7cf0..0000000
Binary files a/data/tile0001.bmp and /dev/null differ
diff --git a/data/tile0010.bmp b/data/tile0010.bmp
deleted file mode 100644
index 9316c35..0000000
Binary files a/data/tile0010.bmp and /dev/null differ
diff --git a/data/tile0011.bmp b/data/tile0011.bmp
deleted file mode 100644
index 0af0a55..0000000
Binary files a/data/tile0011.bmp and /dev/null differ
diff --git a/data/tile0100.bmp b/data/tile0100.bmp
deleted file mode 100644
index 331b79f..0000000
Binary files a/data/tile0100.bmp and /dev/null differ
diff --git a/data/tile0101.bmp b/data/tile0101.bmp
deleted file mode 100644
index e1f7676..0000000
Binary files a/data/tile0101.bmp and /dev/null differ
diff --git a/data/tile0110.bmp b/data/tile0110.bmp
deleted file mode 100644
index a8c1e02..0000000
Binary files a/data/tile0110.bmp and /dev/null differ
diff --git a/data/tile0111.bmp b/data/tile0111.bmp
deleted file mode 100644
index 6740d0c..0000000
Binary files a/data/tile0111.bmp and /dev/null differ
diff --git a/data/tile1000.bmp b/data/tile1000.bmp
deleted file mode 100644
index 659475b..0000000
Binary files a/data/tile1000.bmp and /dev/null differ
diff --git a/data/tile1001.bmp b/data/tile1001.bmp
deleted file mode 100644
index bbf570f..0000000
Binary files a/data/tile1001.bmp and /dev/null differ
diff --git a/data/tile1010.bmp b/data/tile1010.bmp
deleted file mode 100644
index fbbd7e6..0000000
Binary files a/data/tile1010.bmp and /dev/null differ
diff --git a/data/tile1011.bmp b/data/tile1011.bmp
deleted file mode 100644
index 6cce6c0..0000000
Binary files a/data/tile1011.bmp and /dev/null differ
diff --git a/data/tile1100.bmp b/data/tile1100.bmp
deleted file mode 100644
index 3c883d2..0000000
Binary files a/data/tile1100.bmp and /dev/null differ
diff --git a/data/tile1101.bmp b/data/tile1101.bmp
deleted file mode 100644
index 20f2488..0000000
Binary files a/data/tile1101.bmp and /dev/null differ
diff --git a/data/tile1110.bmp b/data/tile1110.bmp
deleted file mode 100644
index 9df81d6..0000000
Binary files a/data/tile1110.bmp and /dev/null differ
diff --git a/data/tile1111.bmp b/data/tile1111.bmp
deleted file mode 100644
index 47e5bb5..0000000
Binary files a/data/tile1111.bmp and /dev/null differ
diff --git a/main.c b/main.c
index d5942a1..bbe1921 100644
--- a/main.c
+++ b/main.c
@@ -1,114 +1,45 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <math.h>
 #include "GameLib.h"
 
 
-#define MAP_ANCHO 11
-#define MAP_ALTO 9
-
-DrawImg tiles[20];
-int mapa[MAP_ANCHO][MAP_ALTO];
-
-// Dibujar el mapa
-void DrawMapa(){
-	int x;
-	int y;
-	int value;
-
-	// dibujar el entorno
-	for(x=0;x<MAP_ANCHO-1;x++){
-		for(y=0;y<MAP_ALTO-1;y++){
-			value  = mapa[x  ][y  ] * 8;
-			value += mapa[x+1][y  ] * 4;
-			value += mapa[x  ][y+1] * 2;
-			value += mapa[x+1][y+1] * 1;
-			Draw_DrawImg(tiles[value], x*64, y*64);
-		}
-	}
-}
-
-// Crear un mapa aleatorio
-int CrearMapa(){
-	int x;
-	int y;
-	double rnd;
-
-	for(x=0;x<MAP_ANCHO;x++){
-		for(y=0;y<MAP_ALTO;y++){
-			rnd=rand();
-			rnd=rnd/RAND_MAX;
-			if(rnd>0.7){
-				mapa[x][y]=0;
-			}else{
-				mapa[x][y]=1;
-			}
-		}
-	}
-	return 0;
-}
-
 DrawFnt font;
-DrawFnt fonts;
-DrawImg bisho;
-float xacel,yacel;
-int xpos=0,ypos=0;
+DrawFnt font_shad;
+
+DrawImg img_bisho;
+DrawImg img_bisho2;
+DrawImg img_bloque;
+
 AudioSnd coin;
-int t_start,t_end;
-int frames=0;
 
-int ProcGame(){
-	int i;
-
-	//Draw_Clean(0,0,0);
-	DrawMapa();
-
-	if(Input_GetKey(InputKey_Up) && yacel>-10){
-		yacel-=2;
-	}
-	if(Input_GetKey(InputKey_Down) && yacel<10){
-		yacel+=2;
-	}
-	if(Input_GetKey(InputKey_Left) && xacel>-10){
-		xacel-=2;
-	}
-	if(Input_GetKey(InputKey_Right) && xacel<10){
-		xacel+=2;
-	}
-	if(xacel!=0){
-		xpos+=xacel;
-		if(xacel>0){
-			xacel-=1;
-		}else{
-			xacel+=1;
-		}
-	}
-	if(yacel!=0){
-		ypos+=yacel;
-		if(yacel>0){
-			yacel-=1;
-		}else{
-			yacel+=1;
-		}
-	}
-	Draw_DrawImgCenter(bisho,xpos,ypos);
-	Draw_DrawText(fonts,"BISHO!",xpos-15,ypos-23);
-	Draw_DrawText(font ,"BISHO!",xpos-16,ypos-24);
+Entity *bisho;
+Entity *bisho2;
+Entity *bloque;
 
 
+
+void ProcGame(){
+	Draw_Clean(0,0,0);
+}
+
+void PostProcGame(){
 	if(Input_GetKey(InputKey_Action1)==InputKey_Pressed){
 		Audio_PlaySound(coin,1,1);
 	}
 
-	/*for(i=0;i<1000;i++){
-		Draw_DrawImgCenter(bisho,rand()%640,rand()%480);
-	}*/
+	Draw_DrawText(font_shad,"Hola Mundo!",11,11);
+	Draw_DrawText(font     ,"Hola Mundo!",10,10);
 
-	Draw_DrawText(fonts,"Hola Mundo!",11,11);
-	Draw_DrawText(font ,"Hola Mundo!",10,10);
+}
 
-	frames++;
+void player_proc(Entity *e){
+	vec2 vel;
 
-	return(1);
+	if(Input_GetDir(vel)){
+		vec2_scale(vel,vel,2.0f);
+		Entity_AddVelLimit(e,vel,10.0f);
+	}
 }
 
 int main(int argc,char *argv[]){
@@ -117,46 +48,84 @@ int main(int argc,char *argv[]){
 
 	GameLib_Init(640,480,"Game",60);
 
-	tiles[0]  = Draw_LoadImage("data/tile0000.bmp");
-	tiles[1]  = Draw_LoadImage("data/tile0001.bmp");
-	tiles[2]  = Draw_LoadImage("data/tile0010.bmp");
-	tiles[3]  = Draw_LoadImage("data/tile0011.bmp");
-	tiles[4]  = Draw_LoadImage("data/tile0100.bmp");
-	tiles[5]  = Draw_LoadImage("data/tile0101.bmp");
-	tiles[6]  = Draw_LoadImage("data/tile0110.bmp");
-	tiles[7]  = Draw_LoadImage("data/tile0111.bmp");
-	tiles[8]  = Draw_LoadImage("data/tile1000.bmp");
-	tiles[9]  = Draw_LoadImage("data/tile1001.bmp");
-	tiles[10] = Draw_LoadImage("data/tile1010.bmp");
-	tiles[11] = Draw_LoadImage("data/tile1011.bmp");
-	tiles[12] = Draw_LoadImage("data/tile1100.bmp");
-	tiles[13] = Draw_LoadImage("data/tile1101.bmp");
-	tiles[14] = Draw_LoadImage("data/tile1110.bmp");
-	tiles[15] = Draw_LoadImage("data/tile1111.bmp");
-
 	font=Draw_DefaultFont(255,255,255,255);
-	fonts=Draw_DefaultFont(0,0,0,127);
+	font_shad=Draw_DefaultFont(0,0,0,127);
 
-	//bisho=Draw_LoadImage("data/bisho.bmp");
-	//Draw_ImgSetKeyCol(bisho,0,255,0);
-	//Draw_ImgSetAlpha(bisho,127);
+	img_bisho=Draw_LoadImage("data/bisho_alpha.bmp");
+	Draw_ImgSetAlpha(img_bisho,255);
+	Draw_SetOffset(img_bisho,-16,-16);
 
-	bisho=Draw_LoadImage("data/bisho_alpha.bmp");
-	Draw_ImgSetAlpha(bisho,255);
-
-	xpos=320;
-	ypos=240;
+	img_bisho2=Draw_LoadImage("data/bisho2_alpha.bmp");
+	Draw_ImgSetAlpha(img_bisho2,255);
+	Draw_SetOffset(img_bisho2,-16,-16);
 
+	img_bloque=Draw_LoadImage("data/bloque.bmp");
+	Draw_ImgSetAlpha(img_bloque,255);
+	Draw_SetOffset(img_bloque,-16,-16);
 
 	coin=Audio_LoadSound("data/coin.wav");
 
 
-	CrearMapa();
+	bisho=Entity_New();
+	bisho->radius=16.0f;
+	bisho->img=img_bisho;
+	bisho->proc=player_proc;
+
+	bisho2=Entity_New();
+	bisho2->radius=16.0f;
+	bisho2->fric_static=0.1f;
+	bisho2->elast=0.0f;
+	bisho2->img=img_bisho2;
+
+	bloque=Entity_New();
+	bloque->mass=-1.0f;
+	bloque->radius=15.5f;
+	bloque->img=img_bloque;
+
+
+	int i;
+	Entity *e;
+	for(i=0;i<20;i++){
+		e=Entity_Copy(bloque);
+		vec2_set(e->pos,16+i*32,16);
+		GameLib_AddEntity(e);
+	}
+	for(i=0;i<20;i++){
+		e=Entity_Copy(bloque);
+		vec2_set(e->pos,16+i*32,464);
+		GameLib_AddEntity(e);
+	}
+	for(i=1;i<14;i++){
+		e=Entity_Copy(bloque);
+		vec2_set(e->pos,16,16+i*32);
+		GameLib_AddEntity(e);
+	}
+	for(i=1;i<14;i++){
+		e=Entity_Copy(bloque);
+		vec2_set(e->pos,624,16+i*32);
+		GameLib_AddEntity(e);
+	}
+
+	for(i=0;i<4;i++){
+		e=Entity_Copy(bloque);
+		vec2_set(e->pos,100,100+i*32);
+		GameLib_AddEntity(e);
+	}
+	for(i=0;i<4;i++){
+		e=Entity_Copy(bloque);
+		vec2_set(e->pos,164,100+i*32);
+		GameLib_AddEntity(e);
+	}
+	e=Entity_Copy(bisho2);
+	vec2_set(e->pos,132,100);
+	GameLib_AddEntity(e);
+
+	e=Entity_Copy(bisho);
+	vec2_set(e->pos,132,50);
+	GameLib_AddEntity(e);
+
+	GameLib_Loop(ProcGame,PostProcGame);
 
-	t_start=SDL_GetTicks();
-	Draw_Loop(ProcGame);
-	t_end=SDL_GetTicks();
-	printf("%d %d %.2f\n",t_end-t_start,frames,frames/((t_end-t_start)/1000.0f));
 
 	return(0);
 }