#include <X11/Xlib.h>
#include <stdlib.h>
#include <X11/keysym.h>
#include <cstring>
#include <iostream>
using namespace std;
enum CELL_STATE { CELL_EMPTY, CELL_O, CELL_X };
enum GAME_STATE { X_TURN, O_TURN, X_WON, O_WON, DRAW }; class Game {
public:
Game(); CELL_STATE getCellState(int x, int y);
GAME_STATE getGameState(); bool makeMove(int x, int y);
bool makeRandomMove();
void restart();
private:
CELL_STATE _boardState[3][3];
GAME_STATE _gameState;
int _turnsPassed; void _checkForEnd();
}; inline CELL_STATE Game::getCellState(int x, int y) {
return _boardState[x][y];
} inline GAME_STATE Game::getGameState() {
return _gameState;
} Game::Game() {
restart();
} void Game::restart() {
for(int i = 0; i < 3; i++) {
for(int j = 0; j < 3; j++) {
_boardState[i][j] = CELL_EMPTY;
}
}
_gameState = X_TURN;
_turnsPassed = 0;
} bool Game::makeMove(int x, int y) {
GAME_STATE nextState;
CELL_STATE curPlayerCell; if(_gameState == O_TURN) {
curPlayerCell = CELL_O;
nextState = X_TURN;
} else if(_gameState == X_TURN) {
curPlayerCell = CELL_X;
nextState = O_TURN;
} else {
return false;
} if(_boardState[x][y] != CELL_EMPTY) {
return false;
} _boardState[x][y] = curPlayerCell;
_turnsPassed++;
_gameState = nextState; _checkForEnd();
return true;
} bool Game::makeRandomMove() {
GAME_STATE nextState;
CELL_STATE curPlayerCell; if(_gameState == O_TURN) {
curPlayerCell = CELL_O;
nextState = X_TURN;
} else if(_gameState == X_TURN) {
curPlayerCell = CELL_X;
nextState = O_TURN;
} else {
return false;
} int nFreeCells = 0;
int freeCells[9][2];
for(int i = 0; i < 3; i++) {
for(int j = 0; j < 3; j++) {
if(_boardState[i][j] == CELL_EMPTY) {
freeCells[nFreeCells][0] = i;
freeCells[nFreeCells][1] = j;
nFreeCells++;
}
}
} if(nFreeCells == 0) {
return false;
} int choice = rand() % nFreeCells;
int x = freeCells[choice][0];
int y = freeCells[choice][1]; _boardState[x][y] = curPlayerCell;
_turnsPassed++;
_gameState = nextState; _checkForEnd();
return true;
} void Game::_checkForEnd() {
if(_turnsPassed == 9) {
_gameState = DRAW;
} CELL_STATE winningCell = CELL_EMPTY; for(int i = 0; i < 3; i++) {
if((_boardState[i][0] == _boardState[i][1]) &&
(_boardState[i][1] == _boardState[i][2]) &&
(_boardState[i][0] != CELL_EMPTY)) {
winningCell = _boardState[i][0];
}
}
for(int i = 0; i < 3; i++) {
if((_boardState[0][i] == _boardState[1][i]) &&
(_boardState[1][i] == _boardState[2][i]) &&
(_boardState[0][1] != CELL_EMPTY)) {
winningCell = _boardState[0][i];
}
}
if((_boardState[0][0] == _boardState[1][1]) &&
(_boardState[1][1] == _boardState[2][2]) &&
(_boardState[0][0] != CELL_EMPTY)) {
winningCell = _boardState[0][0];
}
if((_boardState[2][0] == _boardState[1][1]) &&
(_boardState[1][1] == _boardState[0][2]) &&
(_boardState[2][0] != CELL_EMPTY)) {
winningCell = _boardState[2][0];
} if(winningCell == CELL_X) {
_gameState = X_WON;
} else if(winningCell == CELL_O) {
_gameState = O_WON;
}
} class HelloWorld {
public:
HelloWorld(Display* display); Window getWindow(); void draw();
void map(); void handleKeyPress(const XKeyEvent& event);
void handleMousePress(const XButtonEvent& event);
void restartGame();
private:
const static int MIN_CELL_SIZE;
const static int STRING_HEIGHT;
const static char WINDOW_FONT[]; Display* _display;
Screen* _screen;
Window _window; Font _font;
unsigned long _blackColor;
unsigned long _whiteColor; Game _game; void _drawO(const GC& gc, int x, int y, int w, int h);
void _drawX(const GC& gc, int x, int y, int w, int h); void _drawString(const GC& gc, const char* str, int x, int y);
void _drawStringCentered(const GC& gc, const char* str, int x, int y, int w, int h);
}; inline Window HelloWorld::getWindow() {
return _window;
} const int HelloWorld::MIN_CELL_SIZE = 50;
const int HelloWorld::STRING_HEIGHT = 20;
const char HelloWorld::WINDOW_FONT[] = "-*-*-*-*-*-*-12-*-*-*-*-*-*-*"; HelloWorld::HelloWorld(Display* display) :
_game() { _display = display;
_screen = XDefaultScreenOfDisplay(display); _blackColor = BlackPixelOfScreen(_screen);
_whiteColor = WhitePixelOfScreen(_screen);
_font = XLoadFont(_display, WINDOW_FONT); int screenWidth = XWidthOfScreen(_screen);
int screenHeight = XHeightOfScreen(_screen); int windowWidth = MIN_CELL_SIZE * 3;
int windowHeight = MIN_CELL_SIZE * 3 + STRING_HEIGHT * 3;
int windowX = (screenWidth + windowWidth) / 2;
int windowY = (screenHeight + windowHeight) / 2;
_window = XCreateSimpleWindow(_display, XRootWindowOfScreen(_screen),
windowX, windowY, windowWidth, windowHeight, 1, _blackColor,
_whiteColor); long eventMask = ButtonPressMask | ExposureMask | KeyPressMask;
XSelectInput(_display, _window, eventMask); draw();
} void HelloWorld::draw() {
// Getting window dimensions.
Window rootWindow;
int x, y;
unsigned int width, height, borderWidth, bitDepth;
XGetGeometry(_display, _window, &rootWindow, &x, &y, &width, &height,
&borderWidth, &bitDepth); // Setting up the GC.
GC gc = XDefaultGCOfScreen(_screen);
XSetBackground(_display, gc, _whiteColor);
XSetFont(_display, gc, _font);
XSetForeground(_display, gc, _blackColor); // Clearing the window.
XClearArea(_display, _window, 0, 0, width, height, false); // Is the window large enough for us?
if((width < MIN_CELL_SIZE * 3) ||
(height < (MIN_CELL_SIZE * 3 + STRING_HEIGHT * 3))) {
_drawStringCentered(gc, "Window too small.", 0, 0, width, height);
return;
} // Calculating grid cell sizes.
int xStepSize = width / 3;
int yStepSize = (height - STRING_HEIGHT * 3) / 3; // Drawing glyphs.
for(int i = 0; i < 3; i++) {
for(int j = 0; j < 3; j++) {
switch(_game.getCellState(i, j)) {
case CELL_O:
_drawO(gc, xStepSize * i, STRING_HEIGHT * 2 + yStepSize * j,
xStepSize, yStepSize);
break;
case CELL_X:
_drawX(gc, xStepSize * i, STRING_HEIGHT * 2 + yStepSize * j,
xStepSize, yStepSize);
break;
default:
break;
}
}
}
XSetBackground(_display, gc, _whiteColor);
XSetForeground(_display, gc, _blackColor); // Drawing the grid lines.
for(int i = 0; i <= 3; i++) {
int yValue = STRING_HEIGHT * 2 + yStepSize * i;
XDrawLine(_display, _window, gc, 0, yValue, width, yValue);
}
for(int i = 1; i <= 2; i++) {
int xValue = xStepSize * i;
XDrawLine(_display, _window, gc, xValue, STRING_HEIGHT * 2, xValue,
height - STRING_HEIGHT);
} // Drawing the strings.
_drawStringCentered(gc, "Hello, World!", 0, 0, width, STRING_HEIGHT);
_drawStringCentered(gc, "[R]estart", 0, height - STRING_HEIGHT,
width, STRING_HEIGHT); switch(_game.getGameState()) {
case X_TURN:
_drawStringCentered(gc, "It is your turn to play.", 0, STRING_HEIGHT,
width, STRING_HEIGHT);
break;
case O_TURN:
_drawStringCentered(gc, "Please wait, thinking...", 0, STRING_HEIGHT,
width, STRING_HEIGHT);
break;
case X_WON:
_drawStringCentered(gc, "You have won.", 0, STRING_HEIGHT, width,
STRING_HEIGHT);
break;
case O_WON:
_drawStringCentered(gc, "You have lost.", 0, STRING_HEIGHT, width,
STRING_HEIGHT);
break;
case DRAW:
_drawStringCentered(gc, "It is a draw.", 0, STRING_HEIGHT, width,
STRING_HEIGHT);
break;
default:
break;
}
} void HelloWorld::map() {
XMapWindow(_display, _window);
} void HelloWorld::handleKeyPress(const XKeyEvent& event) {
unsigned int keyCode_r = XKeysymToKeycode(_display, XK_r);
unsigned int keyCode_q = XKeysymToKeycode(_display, XK_q); if(event.keycode == keyCode_r) {
_game.restart();
draw();
} else if(event.keycode == keyCode_q) {
// Quit, somehow
}
} void HelloWorld::handleMousePress(const XButtonEvent& event) {
if(event.button == 1) {
Window rootWindow;
int winX, winY;
unsigned int width, height, borderWidth, bitDepth;
XGetGeometry(_display, _window, &rootWindow, &winX, &winY, &width,
&height, &borderWidth, &bitDepth); if((event.y >= 2 * STRING_HEIGHT) &&
(event.y < (height - STRING_HEIGHT))) {
int xStepSize = width / 3;
int yStepSize = (height - STRING_HEIGHT * 3) / 3; int cellX = event.x / xStepSize;
int cellY = (event.y - STRING_HEIGHT * 2) / yStepSize; if(_game.makeMove(cellX, cellY)) {
if(_game.getGameState() == O_TURN) {
_game.makeRandomMove();
}
draw();
}
}
}
} void HelloWorld::restartGame() {
_game.restart();
draw();
} void HelloWorld::_drawO(const GC& gc, int x, int y, int w, int h) {
XSetBackground(_display, gc, _whiteColor);
XSetForeground(_display, gc, _blackColor);
XFillArc(_display, _window, gc, x + w/10, y + h/10, (w*4)/5, (h*4)/5, 0,
360*64); XSetForeground(_display, gc, _whiteColor);
XFillArc(_display, _window, gc, x + w/5, y + h/5, (w*3)/5, (h*3)/5, 0,
360*64);
} void HelloWorld::_drawX(const GC& gc, int x, int y, int w, int h) {
static const int POINT_COUNT = 12;
static const XPoint RAW_CROSS[] = { {1, 2}, {2, 1}, {5, 4}, {8, 1}, {9, 2},
{6, 5}, {9, 8}, {8, 9}, {5, 6}, {2, 9}, {1, 8}, {4, 5} }; XPoint scaledCross[POINT_COUNT];
for(int i = 0; i < POINT_COUNT; i++) {
scaledCross[i].x = (RAW_CROSS[i].x * w) / 10 + x;
scaledCross[i].y = (RAW_CROSS[i].y * h) / 10 + y;
} XSetBackground(_display, gc, _whiteColor);
XSetForeground(_display, gc, _blackColor);
XFillPolygon(_display, _window, gc, scaledCross, POINT_COUNT, Nonconvex,
CoordModeOrigin);
} void HelloWorld::_drawString(const GC& gc, const char* str, int x, int y) {
XDrawString(_display, _window, gc, x, y, str, strlen(str));
} void HelloWorld::_drawStringCentered(const GC& gc, const char* str, int x, int y,
int w, int h) {
int direction, ascent, descent;
XCharStruct strDimensions;
XTextExtents(XQueryFont(_display, XGContextFromGC(gc)), str, strlen(str),
&direction, &ascent, &descent, &strDimensions); int newX = x + (w - strDimensions.width) / 2;
int newY = y + (h + strDimensions.ascent - strDimensions.descent) / 2;
_drawString(gc, str, newX, newY);
} int main() {
Display* display = XOpenDisplay(NULL);
if(!display) {
cerr << "Unable to connect to X server." << endl;
exit(1);
} HelloWorld mainWindow(display);
mainWindow.map(); XFlush(display); XEvent event;
while(true) {
XNextEvent(display, &event); switch(event.type) {
case ButtonPress:
mainWindow.handleMousePress((XButtonEvent)event.xbutton);
case Expose:
if(event.xexpose.count == 0) {
mainWindow.draw();
}
break;
case KeyPress:
mainWindow.handleKeyPress((XKeyEvent)event.xkey);
default:
break;
}
} XCloseDisplay(display);
return 0;
}