input, changes

src/game/input.cpp

@@ -0,0 +1,27 @@
+#include <game/input.hpp>
+
+namespace Game {
+    const bool* Input::mCurrentKeyStates = nullptr;
+    bool* Input::mPreviousKeyStates = nullptr;
+    int Input::mNumKeys = 0;
+
+    void Input::update() {
+        mPreviousKeyStates = const_cast<bool*>(mCurrentKeyStates);
+        mCurrentKeyStates = SDL_GetKeyboardState(&mNumKeys);
+    }
+
+    bool Input::isKeyPressed(SDL_Scancode key) {
+        if (key < 0 || key >= mNumKeys) return false;
+        return mCurrentKeyStates[key];
+    }
+
+    bool Input::isKeyJustPressed(SDL_Scancode key) {
+        if (key < 0 || key >= mNumKeys) return false;
+        return mCurrentKeyStates[key] && (!mPreviousKeyStates || !mPreviousKeyStates[key]);
+    }
+
+    bool Input::isKeyJustReleased(SDL_Scancode key) {
+        if (key < 0 || key >= mNumKeys) return false;
+        return (!mCurrentKeyStates[key]) && mPreviousKeyStates && mPreviousKeyStates[key];
+    }
+}