diff --git a/source/TileManager.cpp b/source/TileManager.cpp
index 1a64e64..75d34c4 100755
--- a/source/TileManager.cpp
+++ b/source/TileManager.cpp
@@ -34,7 +34,7 @@ TileManager::TileManager(b2World& world) :
  */
 TileManager::Tile::Tile(Type type, const TilePosition& position, b2World& world) :
 		Sprite(getTexture(type), PhysicalData(Vector2f(position.x * TILE_SIZE.x, position.y * TILE_SIZE.y),
-				TILE_SIZE, world, CATEGORY_WORLD, (type == Type::FLOOR) ? MASK_NONE : MASK_ALL, false)),
+				world, CATEGORY_WORLD, (type == Type::FLOOR) ? MASK_NONE : MASK_ALL, false)),
 		mType(type) {
 }
 
diff --git a/source/abstract/Physical.cpp b/source/abstract/Physical.cpp
index 522f941..4039ed0 100755
--- a/source/abstract/Physical.cpp
+++ b/source/abstract/Physical.cpp
@@ -11,14 +11,17 @@
 
 #include <Thor/Vectors.hpp>
 
+const String Physical::KEY_SIZE = "size";
+
 /**
  * Initializes Box2D body.
  *
  * @param data Data needed for construction.
  */
-Physical::Physical(const PhysicalData& data) :
+Physical::Physical(const PhysicalData& data, const Yaml& config) :
 		mDelete(false) {
-	assert(data.size != Vector2i());
+	Vector2i size = config.get<Vector2i>(KEY_SIZE);
+	assert(size != Vector2i());
 
 	b2BodyDef bodyDef;
 	bodyDef.type = (data.moving)
@@ -34,14 +37,14 @@ Physical::Physical(const PhysicalData& data) :
 
 	b2Shape* shape;
 	if (data.circle) {
-		assert(data.size.x == data.size.y);
+		assert(size.x == size.y);
 		shape = new b2CircleShape;
-		shape->m_radius = pixelToMeter(data.size.x) / 2;
+		shape->m_radius = pixelToMeter(size.x) / 2;
 	}
 	else {
 		b2PolygonShape* box = new b2PolygonShape;
-		box->SetAsBox(pixelToMeter(data.size.x) / 2,
-				      pixelToMeter(data.size.y) / 2);
+		box->SetAsBox(pixelToMeter(size.x) / 2,
+				      pixelToMeter(size.y) / 2);
 		shape = dynamic_cast<b2Shape*>(box);
 	}
 
@@ -70,16 +73,15 @@ Physical::~Physical() {
  *
  * @link Physical::PhysicalData
  */
-Physical::PhysicalData::PhysicalData( const Vector2f& position, const Vector2i& size,
-		b2World& world, uint16 category, uint16 maskExclude, bool moving, bool bullet, bool circle) :
-	position(position),
-	size(size),
-	world(world),
-	category(category),
-	maskExclude(maskExclude),
-	moving(moving),
-	bullet(bullet),
-	circle(circle) {
+Physical::PhysicalData::PhysicalData( const Vector2f& position, b2World& world, uint16 category,
+	uint16 maskExclude, bool moving, bool bullet, bool circle) :
+		position(position),
+		world(world),
+		category(category),
+		maskExclude(maskExclude),
+		moving(moving),
+		bullet(bullet),
+		circle(circle) {
 }
 
 /**
diff --git a/source/abstract/Physical.h b/source/abstract/Physical.h
index 66490c3..9415be9 100755
--- a/source/abstract/Physical.h
+++ b/source/abstract/Physical.h
@@ -10,7 +10,11 @@
 
 #include <Box2D/Box2D.h>
 
+#include "../util/String.h"
 #include "../util/Vector.h"
+#include "../util/Yaml.h"
+
+class Yaml;
 
 /**
  * An object with physical properties.
@@ -26,13 +30,10 @@ public:
 	class PhysicalData {
 	public:
 		PhysicalData() = default;
-		PhysicalData(const Vector2f& position, const Vector2i& size, b2World& world,
-				uint16 category, uint16 maskExclude, bool moving, bool bullet = false,
-				bool circle = false);
+		PhysicalData(const Vector2f& position, b2World& world, uint16 category,
+				uint16 maskExclude, bool moving, bool bullet = false, bool circle = false);
 		/// World position of the body in pixel coordinates.
 		const Vector2f& position;
-		/// Pixel size of the body if it is a box.
-		Vector2i size;
 		/// Box2D world object.
 		b2World& world;
 		/// The category for collision filtering. Only one may be set. @link Physical::Category
@@ -72,7 +73,7 @@ public:
 
 // Public functions.
 public:
-	Physical(const PhysicalData& data);
+	Physical(const PhysicalData& data, const Yaml& config);
 	virtual ~Physical() = 0;
 
 	Vector2f getPosition() const;
@@ -97,6 +98,8 @@ protected:
 
 // Private variables.
 private:
+	static const String KEY_SIZE;
+
 	b2Body* mBody;
 	bool mDelete;
 };
diff --git a/source/abstract/Sprite.cpp b/source/abstract/Sprite.cpp
index f264161..a6d46e0 100644
--- a/source/abstract/Sprite.cpp
+++ b/source/abstract/Sprite.cpp
@@ -18,10 +18,10 @@ const String Sprite::KEY_TEXTURE = "texture";
  * @param texturePath Relative path to the texture file in the resource folder.
  */
 Sprite::Sprite(const Yaml& config, const PhysicalData& data) :
-		Physical(data),
+		Physical(data, config),
 		mTexture(ResourceManager::i().acquire(Loader::i()
 				.fromFile<sf::Texture>(config.get<String>(KEY_TEXTURE)))),
-		mSize(data.size) {
+		mSize(Vector2i(getSize())) {
 }
 
 /**
@@ -30,9 +30,9 @@ Sprite::Sprite(const Yaml& config, const PhysicalData& data) :
  * @param texture Pointer to the texture to be used (must already be loaded).
  */
 Sprite::Sprite(const std::shared_ptr<sf::Texture>& texture, const PhysicalData& data) :
-		Physical(data),
+		Physical(data, Yaml("tile.yaml")),
 		mTexture(texture),
-		mSize(data.size) {
+		mSize(Vector2i(getSize())) {
 
 }
 /**
diff --git a/source/effects/Bullet.cpp b/source/effects/Bullet.cpp
index e960bb9..40a9ff4 100755
--- a/source/effects/Bullet.cpp
+++ b/source/effects/Bullet.cpp
@@ -25,7 +25,7 @@ const String Bullet::KEY_SPEED = "speed";
 Bullet::Bullet(const Vector2f& position, b2World& world, Physical& shooter, float direction,
 	const Yaml& config) :
 		Particle(ResourceManager::i().acquire(Loader::i().fromFile<sf::Texture>("bullet.png")),
-				PhysicalData(position, SIZE, world, CATEGORY_PARTICLE, CATEGORY_PARTICLE,
+				PhysicalData(position, world, CATEGORY_PARTICLE, CATEGORY_PARTICLE,
 				true, true, true), config),
 		mShooter(shooter),
 		mDamage(config.get<int>(KEY_DAMAGE)),
diff --git a/source/sprite/Body.cpp b/source/sprite/Body.cpp
index 13ce3c9..989b443 100755
--- a/source/sprite/Body.cpp
+++ b/source/sprite/Body.cpp
@@ -8,7 +8,6 @@
 #include "Body.h"
 
 Body::Body(b2World& world, const Vector2f& position, const Yaml& config) :
-		Sprite(config, PhysicalData(position, Vector2i(50, 50), world,
-			   CATEGORY_NONSOLID, MASK_NONE, false)) {
+		Sprite(config, PhysicalData(position, world, CATEGORY_NONSOLID, MASK_NONE, false)) {
 }
 
diff --git a/source/sprite/Cover.cpp b/source/sprite/Cover.cpp
index 2488f95..bd08f1b 100755
--- a/source/sprite/Cover.cpp
+++ b/source/sprite/Cover.cpp
@@ -8,6 +8,6 @@
 #include "Cover.h"
 
 Cover::Cover(const Vector2f& position, const Vector2i& size, b2World& world, const Yaml& config) :
-		Sprite(config, PhysicalData(position, size, world, CATEGORY_WORLD, MASK_ALL, false)) {
+		Sprite(config, PhysicalData(position, world, CATEGORY_WORLD, MASK_ALL, false)) {
 }
 
diff --git a/source/sprite/Enemy.cpp b/source/sprite/Enemy.cpp
index f1daa09..b5f3444 100644
--- a/source/sprite/Enemy.cpp
+++ b/source/sprite/Enemy.cpp
@@ -10,7 +10,7 @@
 #include "Body.h"
 
 Enemy::Enemy(const Instances& instances, const Vector2f& position, const Yaml& config) :
-		Character(instances, "enemy.png", PhysicalData(position, Vector2i(50, 50), instances.world,
+		Character(instances, "enemy.png", PhysicalData(position, instances.world,
 		       CATEGORY_ACTOR, MASK_ALL, true, false, true), config),
 		mWorld(instances.world),
 		mCollection(instances.collection) {
diff --git a/source/sprite/Player.cpp b/source/sprite/Player.cpp
index c30ae29..12a2cfd 100644
--- a/source/sprite/Player.cpp
+++ b/source/sprite/Player.cpp
@@ -21,7 +21,7 @@ const float Player::POINT_REACHED_DISTANCE = 1.0f;
  * Initializes Sprite.
  */
 Player::Player(const Instances& instances, const Vector2f& position, const Yaml& config) :
-		Character(instances, "player.png", PhysicalData(position, SIZE, instances.world,
+		Character(instances, "player.png", PhysicalData(position, instances.world,
 				CATEGORY_ACTOR, MASK_ALL, true, false, true), config),
 		mWeapon(instances, *this, Yaml("weapon.yaml")),
 		mDirection(0),
diff --git a/source/util/Yaml.h b/source/util/Yaml.h
index 24dc914..0b44fc8 100644
--- a/source/util/Yaml.h
+++ b/source/util/Yaml.h
@@ -13,6 +13,9 @@
 #include <yaml-cpp/yaml.h>
 
 #include "String.h"
+#include "Vector.h"
+
+namespace details {};
 
 /**
  * Interface to a YAML file.
@@ -23,6 +26,7 @@ public:
 	Yaml(const String& filename);
 
 	static void setFolder(const String& folder);
+
 	/**
 	 * Gets a value of a specified type by key. Throws exception if key not found.
 	 *
@@ -43,4 +47,19 @@ private:
 	YAML::Node mNode;
 };
 
+/**
+ * Stream output operators to specialize Yaml::get for other types.
+ */
+namespace {
+	void operator>>(const YAML::Node& node, Vector2i& vector) {
+		node[0] >> vector.x;
+		node[1] >> vector.y;
+	}
+
+	void operator>>(const YAML::Node& node, Vector2f& vector) {
+		node[0] >> vector.x;
+		node[1] >> vector.y;
+	}
+};
+
 #endif /* DG_YAML_H_ */