added control and alt checking

src/raylib.h

@@ -1177,6 +1177,8 @@ RLAPI void PlayAutomationEvent(AutomationEvent event);            // Play a reco
 RLAPI bool IsKeyPressed(int key);                             // Check if a key has been pressed once
 RLAPI bool IsKeyPressedRepeat(int key);                       // Check if a key has been pressed again
 RLAPI bool IsKeyDown(int key);                                // Check if a key is being pressed
+RLAPI bool IsControlKeyDown();                                // Check if any control key is being pressed
+RLAPI bool IsAltKeyDown();                                    // Check if any alt key is being pressed
 RLAPI bool IsKeyReleased(int key);                            // Check if a key has been released once
 RLAPI bool IsKeyUp(int key);                                  // Check if a key is NOT being pressed
 RLAPI int GetKeyPressed(void);                                // Get key pressed (keycode), call it multiple times for keys queued, returns 0 when the queue is empty

src/rcore.c

@@ -3184,6 +3184,16 @@ bool IsKeyDown(int key)
     return down;
 }
 
+bool IsControlKeyDown()
+{
+    return IsKeyDown(KEY_LEFT_CONTROL) || IsKeyDown(KEY_RIGHT_CONTROL);
+}
+
+bool IsAltKeyDown()
+{
+    return IsKeyDown(KEY_LEFT_ALT) || IsKeyDown(KEY_RIGHT_ALT);
+}
+
 // Check if a key has been released once
 bool IsKeyReleased(int key)
 {