feat: optimize color update logic in Ball class and improve vector normalization

src/Ball.cpp

@@ -31,6 +31,15 @@ void Ball::update(float dt, const sf::Vector2f& windowSize) {
 }
 
 void Ball::updateColor() {
+    float currentSpeed =
+        std::sqrt(m_velocity.x * m_velocity.x + m_velocity.y * m_velocity.y);
+
+    static float lastSpeed = 0.0f;
+    if (std::abs(currentSpeed - lastSpeed) < 10.0f) {
+        return;
+    }
+    lastSpeed = currentSpeed;
+
     float speed =
         std::sqrt(m_velocity.x * m_velocity.x + m_velocity.y * m_velocity.y);
 
@@ -39,21 +48,21 @@ void Ball::updateColor() {
 
     sf::Color targetColor;
 
-    if (t < 0.33f) {
+    if (t < 0.33f) {  // Red to orange
         float scaledT = t * 3.0f;
-        targetColor.r = static_cast<std::uint8_t>(0 + scaledT * 128);
-        targetColor.g = static_cast<std::uint8_t>(0);
-        targetColor.b = static_cast<std::uint8_t>(255);
-    } else if (t < 0.66f) {
-        float scaledT = (t - 0.33f) * 3.0f;
-        targetColor.r = static_cast<std::uint8_t>(128 + scaledT * 127);
+        targetColor.r = static_cast<std::uint8_t>(255);
         targetColor.g = static_cast<std::uint8_t>(0 + scaledT * 165);
-        targetColor.b = static_cast<std::uint8_t>(255 - scaledT * 255);
-    } else {
+        targetColor.b = static_cast<std::uint8_t>(0);
+    } else if (t < 0.66f) {  // Orange to yellow
+        float scaledT = (t - 0.33f) * 3.0f;
+        targetColor.r = static_cast<std::uint8_t>(255);
+        targetColor.g = static_cast<std::uint8_t>(165 + scaledT * 90);
+        targetColor.b = static_cast<std::uint8_t>(0);
+    } else {  // Yellow to white
         float scaledT = (t - 0.66f) * 3.0f;
         targetColor.r = static_cast<std::uint8_t>(255);
-        targetColor.g = static_cast<std::uint8_t>(165 - scaledT * 165);
-        targetColor.b = static_cast<std::uint8_t>(0);
+        targetColor.g = static_cast<std::uint8_t>(255);
+        targetColor.b = static_cast<std::uint8_t>(0 + scaledT * 255);
     }
 
     sf::Color currentColor = m_shape.getFillColor();

src/Ball.hpp

@@ -6,18 +6,23 @@
 
 class Ball : public PhysicalObject {
    private:
-    sf::CircleShape m_shape;
+    // Position and physics data
     sf::Vector2f m_velocity;
-    float m_radius;
-    bool m_atRest = false;
     sf::Vector2f m_lastPosition;
     sf::Vector2f m_pixelVelocity;
+    float m_radius;
+
+    // Display data
+    sf::CircleShape m_shape;
     sf::Color m_baseColor;
+
+    // State flags
+    bool m_atRest = false;
+    mutable std::mutex m_mutex;
+
     void handleWallCollision(const sf::Vector2f& windowSize);
     void updateColor();
 
-    mutable std::mutex m_mutex;
-
    public:
     Ball(float radius, const sf::Vector2f& pos, const sf::Vector2f& vel,
          const sf::Color& color);

src/VectorMath.cpp

@@ -8,9 +8,10 @@ float length(const sf::Vector2f& vector) {
 }
 
 sf::Vector2f normalize(const sf::Vector2f& vector) {
-    float len = length(vector);
-    if (len > 0.0001f) {
-        return vector / len;
+    float squaredLen = vector.x * vector.x + vector.y * vector.y;
+    if (squaredLen > 0.0001f) {
+        float invLen = 1.0f / std::sqrt(squaredLen);
+        return sf::Vector2f(vector.x * invLen, vector.y * invLen);
     }
     return vector;
 }