Class KeyboardState

src/main/java/field/graphics/Window.java:1189–1343

        static public Set<Character> charsPressed(KeyboardState before, KeyboardState after) {
            Set<Character> b = new LinkedHashSet<>(after.charsDown.values());
            b.removeAll(before.charsDown.values());
            return b;
        }

        static public Set<Character> charsReleased(KeyboardState before, KeyboardState after) {
            Set<Character> b = new LinkedHashSet<>(before.charsDown.values());
            b.removeAll(after.charsDown.values());
            return b;
        }

        public KeyboardState next(int key, char character, boolean state, long time) {
            Set<Integer> keysDown = new LinkedHashSet<>(this.keysDown);
            Map<Integer, Character> charsDown = new LinkedHashMap<>(this.charsDown);
            if (state) {
                keysDown.add(key);
                charsDown.put(key, character);
            } else {
                keysDown.remove(key);
                charsDown.remove(key);
            }

            return new KeyboardState(keysDown, charsDown, time);
        }

        public KeyboardState withKey(int key, boolean down) {
            Set<Integer> keysDown = new LinkedHashSet<>(this.keysDown);
            Map<Integer, Character> charsDown = new LinkedHashMap<>(this.charsDown);
            if (down) {
                keysDown.add(key);
            } else {
                keysDown.remove(key);
            }

            return new KeyboardState(keysDown, charsDown, time);
        }

        public KeyboardState withChar(char c, boolean down) {
            Set<Integer> keysDown = new LinkedHashSet<>(this.keysDown);
            Map<Integer, Character> charsDown = new LinkedHashMap<>(this.charsDown);
            if (down) {
                charsDown.put((int) c, c);
            } else {
                charsDown.remove((int) c);
            }

            return new KeyboardState(keysDown, charsDown, time);
        }

        public boolean isShiftDown() {
            return keysDown.contains(GLFW_KEY_LEFT_SHIFT) || keysDown.contains(GLFW_KEY_RIGHT_SHIFT);
        }

        public boolean isAltDown() {
            return keysDown.contains(GLFW_KEY_LEFT_ALT) || keysDown.contains(GLFW_KEY_RIGHT_ALT);
        }

        public boolean isSuperDown() {