--- /dev/null
+/**
+ * Example of cooperative rendering into one window by two processes.
+ * The first instance of the program creates the GLX window.
+ * The second instance of the program gets the window ID from the first
+ * and draws into it.
+ * Socket IPC is used for synchronization.
+ *
+ * Usage:
+ * 1. run 'corender &'
+ * 2. run 'corender 2' (any arg will do)
+ *
+ * Brian Paul
+ * 11 Oct 2007
+ */
+
+
+#include <GL/gl.h>
+#include <GL/glx.h>
+#include <assert.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <X11/keysym.h>
+#include <unistd.h>
+#include "ipc.h"
+
+
+static int MyID = 0; /* 0 or 1 */
+static int WindowID = 0;
+static GLXContext Context = 0;
+static int Width = 700, Height = 350;
+static int Rot = 0;
+static int Sock = 0;
+
+static GLfloat Red[4] = {1.0, 0.2, 0.2, 1.0};
+static GLfloat Blue[4] = {0.2, 0.2, 1.0, 1.0};
+
+static int Sync = 1; /** synchronized rendering? */
+
+
+static void
+setup_ipc(void)
+{
+ int k, port = 10001;
+
+ if (MyID == 0) {
+ /* I'm the first one, wait for connection from second */
+ k = CreatePort(&port);
+ assert(k != -1);
+
+ printf("Waiting for connection from another 'corender'\n");
+ Sock = AcceptConnection(k);
+
+ printf("Got connection, sending windowID\n");
+
+ /* send windowID */
+ SendData(Sock, &WindowID, sizeof(WindowID));
+ }
+ else {
+ /* I'm the second one, connect to first */
+ char hostname[1000];
+
+ MyHostName(hostname, 1000);
+ Sock = Connect(hostname, port);
+ assert(Sock != -1);
+
+ /* get windowID */
+ ReceiveData(Sock, &WindowID, sizeof(WindowID));
+ printf("Contacted first 'corender', getting WindowID\n");
+ }
+}
+
+
+
+/** from GLUT */
+static void
+doughnut(GLfloat r, GLfloat R, GLint nsides, GLint rings)
+{
+ int i, j;
+ GLfloat theta, phi, theta1;
+ GLfloat cosTheta, sinTheta;
+ GLfloat cosTheta1, sinTheta1;
+ GLfloat ringDelta, sideDelta;
+
+ ringDelta = 2.0 * M_PI / rings;
+ sideDelta = 2.0 * M_PI / nsides;
+
+ theta = 0.0;
+ cosTheta = 1.0;
+ sinTheta = 0.0;
+ for (i = rings - 1; i >= 0; i--) {
+ theta1 = theta + ringDelta;
+ cosTheta1 = cos(theta1);
+ sinTheta1 = sin(theta1);
+ glBegin(GL_QUAD_STRIP);
+ phi = 0.0;
+ for (j = nsides; j >= 0; j--) {
+ GLfloat cosPhi, sinPhi, dist;
+
+ phi += sideDelta;
+ cosPhi = cos(phi);
+ sinPhi = sin(phi);
+ dist = R + r * cosPhi;
+
+ glNormal3f(cosTheta1 * cosPhi, -sinTheta1 * cosPhi, sinPhi);
+ glVertex3f(cosTheta1 * dist, -sinTheta1 * dist, r * sinPhi);
+ glNormal3f(cosTheta * cosPhi, -sinTheta * cosPhi, sinPhi);
+ glVertex3f(cosTheta * dist, -sinTheta * dist, r * sinPhi);
+ }
+ glEnd();
+ theta = theta1;
+ cosTheta = cosTheta1;
+ sinTheta = sinTheta1;
+ }
+}
+
+
+static void
+redraw(Display *dpy)
+{
+ int dbg = 0;
+
+ glXMakeCurrent(dpy, WindowID, Context);
+ glEnable(GL_LIGHTING);
+ glEnable(GL_LIGHT0);
+ glEnable(GL_DEPTH_TEST);
+ glClearColor(0.5, 0.5, 0.5, 0.0);
+
+ if (MyID == 0) {
+ /* First process */
+
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+ glPushMatrix();
+ glTranslatef(-1, 0, 0);
+ glRotatef(Rot, 1, 0, 0);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, Red);
+ doughnut(0.5, 2.0, 20, 30);
+ glPopMatrix();
+
+ glFinish();
+ if (!Sync) {
+ usleep(1000*10);
+ }
+
+ /* signal second process to render */
+ if (Sync) {
+ int code = 1;
+ if (dbg) printf("0: send signal\n");
+ SendData(Sock, &code, sizeof(code));
+ SendData(Sock, &Rot, sizeof(Rot));
+ }
+
+ /* wait for second process to finish rendering */
+ if (Sync) {
+ int code = 0;
+ if (dbg) printf("0: wait signal\n");
+ ReceiveData(Sock, &code, sizeof(code));
+ if (dbg) printf("0: got signal\n");
+ assert(code == 2);
+ }
+
+ }
+ else {
+ /* Second process */
+
+ /* wait for first process's signal for me to render */
+ if (Sync) {
+ int code = 0;
+ if (dbg) printf("1: wait signal\n");
+ ReceiveData(Sock, &code, sizeof(code));
+ ReceiveData(Sock, &Rot, sizeof(Rot));
+
+ if (dbg) printf("1: got signal\n");
+ assert(code == 1);
+ }
+
+ /* XXX this clear should not be here, but for some reason, it
+ * makes things _mostly_ work correctly w/ NVIDIA's driver.
+ * There's only occasional glitches.
+ * Without this glClear(), depth buffer for the second process
+ * is pretty much broken.
+ */
+ //glClear(GL_DEPTH_BUFFER_BIT);
+
+ glPushMatrix();
+ glTranslatef(1, 0, 0);
+ glRotatef(Rot + 90 , 1, 0, 0);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, Blue);
+ doughnut(0.5, 2.0, 20, 30);
+ glPopMatrix();
+ glFinish();
+
+ glXSwapBuffers(dpy, WindowID);
+ usleep(1000*10);
+
+ /* signal first process that I'm done rendering */
+ if (Sync) {
+ int code = 2;
+ if (dbg) printf("1: send signal\n");
+ SendData(Sock, &code, sizeof(code));
+ }
+ }
+}
+
+
+static void
+resize(Display *dpy, int width, int height)
+{
+ float ar = (float) width / height;
+
+ glXMakeCurrent(dpy, WindowID, Context);
+
+ glViewport(0, 0, width, height);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glFrustum(-ar, ar, 1.0, -1.0, 5.0, 200.0);
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glTranslatef(0, 0, -15);
+
+ Width = width;
+ Height = height;
+}
+
+
+
+static void
+set_window_title(Display *dpy, Window win, const char *title)
+{
+ XSizeHints sizehints;
+ sizehints.flags = 0;
+ XSetStandardProperties(dpy, win, title, title,
+ None, (char **)NULL, 0, &sizehints);
+}
+
+
+static Window
+make_gl_window(Display *dpy, XVisualInfo *visinfo, int width, int height)
+{
+ int scrnum;
+ XSetWindowAttributes attr;
+ unsigned long mask;
+ Window root;
+ Window win;
+ int x = 0, y = 0;
+ char *name = NULL;
+
+ scrnum = DefaultScreen( dpy );
+ root = RootWindow( dpy, scrnum );
+
+ /* window attributes */
+ attr.background_pixel = 0;
+ attr.border_pixel = 0;
+ attr.colormap = XCreateColormap( dpy, root, visinfo->visual, AllocNone);
+ attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
+ mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;
+
+ win = XCreateWindow( dpy, root, x, y, width, height,
+ 0, visinfo->depth, InputOutput,
+ visinfo->visual, mask, &attr );
+
+ /* set hints and properties */
+ {
+ XSizeHints sizehints;
+ sizehints.x = x;
+ sizehints.y = y;
+ sizehints.width = width;
+ sizehints.height = height;
+ sizehints.flags = USSize | USPosition;
+ XSetNormalHints(dpy, win, &sizehints);
+ XSetStandardProperties(dpy, win, name, name,
+ None, (char **)NULL, 0, &sizehints);
+ }
+
+ return win;
+}
+
+
+static void
+set_event_mask(Display *dpy, Window win)
+{
+ XSetWindowAttributes attr;
+ attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
+ XChangeWindowAttributes(dpy, win, CWEventMask, &attr);
+}
+
+
+static void
+event_loop(Display *dpy)
+{
+ while (1) {
+ while (XPending(dpy) > 0) {
+ XEvent event;
+ XNextEvent(dpy, &event);
+
+ switch (event.type) {
+ case Expose:
+ redraw(dpy);
+ break;
+ case ConfigureNotify:
+ resize(dpy, event.xconfigure.width, event.xconfigure.height);
+ break;
+ case KeyPress:
+ {
+ char buffer[10];
+ int r, code;
+ code = XLookupKeysym(&event.xkey, 0);
+ if (code == XK_Left) {
+ }
+ else {
+ r = XLookupString(&event.xkey, buffer, sizeof(buffer),
+ NULL, NULL);
+ if (buffer[0] == 27) {
+ exit(0);
+ }
+ }
+ }
+ default:
+ /* nothing */
+ ;
+ }
+ }
+
+ if (MyID == 0 || !Sync)
+ Rot += 1;
+ redraw(dpy);
+ }
+}
+
+
+static XVisualInfo *
+choose_visual(Display *dpy)
+{
+ int attribs[] = { GLX_RGBA,
+ GLX_RED_SIZE, 1,
+ GLX_GREEN_SIZE, 1,
+ GLX_BLUE_SIZE, 1,
+ GLX_DOUBLEBUFFER,
+ GLX_DEPTH_SIZE, 1,
+ None };
+ int scrnum = DefaultScreen( dpy );
+ return glXChooseVisual(dpy, scrnum, attribs);
+}
+
+
+static void
+parse_opts(int argc, char *argv[])
+{
+ if (argc > 1) {
+ MyID = 1;
+ }
+}
+
+
+int
+main( int argc, char *argv[] )
+{
+ Display *dpy;
+ XVisualInfo *visinfo;
+
+ parse_opts(argc, argv);
+
+ dpy = XOpenDisplay(NULL);
+
+ visinfo = choose_visual(dpy);
+
+ Context = glXCreateContext( dpy, visinfo, NULL, True );
+ if (!Context) {
+ printf("Error: glXCreateContext failed\n");
+ exit(1);
+ }
+
+ if (MyID == 0) {
+ WindowID = make_gl_window(dpy, visinfo, Width, Height);
+ set_window_title(dpy, WindowID, "corender");
+ XMapWindow(dpy, WindowID);
+ /*printf("WindowID 0x%x\n", (int) WindowID);*/
+ }
+
+ /* do ipc hand-shake here */
+ setup_ipc();
+ assert(Sock);
+ assert(WindowID);
+
+ if (MyID == 1) {
+ set_event_mask(dpy, WindowID);
+ }
+
+ resize(dpy, Width, Height);
+
+ event_loop(dpy);
+
+ return 0;
+}
--- /dev/null
+/* Copyright (c) 2003 Tungsten Graphics, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files ("the
+ * Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions: The above copyright notice, the Tungsten
+ * Graphics splash screen, and this permission notice shall be included
+ * in all copies or substantial portions of the Software. THE SOFTWARE
+ * IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+ * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+ * SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR
+ * THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/*
+ * Simple IPC API
+ * Brian Paul
+ */
+
+
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include "ipc.h"
+
+#if defined(IRIX) || defined(irix)
+typedef int socklen_t;
+#endif
+
+#define NO_DELAY 1
+
+#define DEFAULT_MASTER_PORT 7011
+
+
+/*
+ * Return my hostname in <nameOut>.
+ * Return 1 for success, 0 for error.
+ */
+int
+MyHostName(char *nameOut, int maxNameLength)
+{
+ int k = gethostname(nameOut, maxNameLength);
+ return k==0;
+}
+
+
+/*
+ * Create a socket attached to a port. Later, we can call AcceptConnection
+ * on the socket returned from this function.
+ * Return the new socket number or -1 if error.
+ */
+int
+CreatePort(int *port)
+{
+ char hostname[1000];
+ struct sockaddr_in servaddr;
+ struct hostent *hp;
+ int so_reuseaddr = 1;
+ int tcp_nodelay = 1;
+ int sock, k;
+
+ /* create socket */
+ sock = socket(AF_INET, SOCK_STREAM, 0);
+ assert(sock > 2);
+
+ /* get my host name */
+ k = gethostname(hostname, 1000);
+ assert(k == 0);
+
+ /* get hostent info */
+ hp = gethostbyname(hostname);
+ assert(hp);
+
+ /* initialize the servaddr struct */
+ memset(&servaddr, 0, sizeof(servaddr) );
+ servaddr.sin_family = AF_INET;
+ servaddr.sin_port = htons((unsigned short) (*port));
+ memcpy((char *) &servaddr.sin_addr, hp->h_addr,
+ sizeof(servaddr.sin_addr));
+
+ /* deallocate when we exit */
+ k = setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
+ (char *) &so_reuseaddr, sizeof(so_reuseaddr));
+ assert(k==0);
+
+ /* send packets immediately */
+#if NO_DELAY
+ k = setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
+ (char *) &tcp_nodelay, sizeof(tcp_nodelay));
+ assert(k==0);
+#endif
+
+ if (*port == 0)
+ *port = DEFAULT_MASTER_PORT;
+
+ k = 1;
+ while (k && (*port < 65534)) {
+ /* bind our address to the socket */
+ servaddr.sin_port = htons((unsigned short) (*port));
+ k = bind(sock, (struct sockaddr *) &servaddr, sizeof(servaddr));
+ if (k)
+ *port = *port + 1;
+ }
+
+#if 0
+ printf("###### Real Port: %d\n", *port);
+#endif
+
+ /* listen for connections */
+ k = listen(sock, 100);
+ assert(k == 0);
+
+ return sock;
+}
+
+
+/*
+ * Accept a connection on the named socket.
+ * Return a new socket for the new connection, or -1 if error.
+ */
+int
+AcceptConnection(int socket)
+{
+ struct sockaddr addr;
+ socklen_t addrLen;
+ int newSock;
+
+ addrLen = sizeof(addr);
+ newSock = accept(socket, &addr, &addrLen);
+ if (newSock == 1)
+ return -1;
+ else
+ return newSock;
+}
+
+
+/*
+ * Contact the server running on the given host on the named port.
+ * Return socket number or -1 if error.
+ */
+int
+Connect(const char *hostname, int port)
+{
+ struct sockaddr_in servaddr;
+ struct hostent *hp;
+ int sock, k;
+ int tcp_nodelay = 1;
+
+ assert(port);
+
+ sock = socket(AF_INET, SOCK_STREAM, 0);
+ assert(sock >= 0);
+
+ hp = gethostbyname(hostname);
+ assert(hp);
+
+ memset(&servaddr, 0, sizeof(servaddr));
+ servaddr.sin_family = AF_INET;
+ servaddr.sin_port = htons((unsigned short) port);
+ memcpy((char *) &servaddr.sin_addr, hp->h_addr, sizeof(servaddr.sin_addr));
+
+ k = connect(sock, (struct sockaddr *) &servaddr, sizeof(servaddr));
+ if (k != 0) {
+ perror("Connect:");
+ return -1;
+ }
+
+#if NO_DELAY
+ /* send packets immediately */
+ k = setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
+ (char *) &tcp_nodelay, sizeof(tcp_nodelay));
+ assert(k==0);
+#endif
+
+ return sock;
+}
+
+
+void
+CloseSocket(int socket)
+{
+ close(socket);
+}
+
+
+int
+SendData(int socket, const void *data, int bytes)
+{
+ int sent = 0;
+ int b;
+
+ while (sent < bytes) {
+ b = write(socket, (char *) data + sent, bytes - sent);
+ if (b <= 0)
+ return -1; /* something broke */
+ sent += b;
+ }
+ return sent;
+}
+
+
+int
+ReceiveData(int socket, void *data, int bytes)
+{
+ int received = 0, b;
+
+ while (received < bytes) {
+ b = read(socket, (char *) data + received, bytes - received);
+ if (b <= 0)
+ return -1;
+ received += b;
+ }
+ return received;
+}
+
+
+int
+SendString(int socket, const char *str)
+{
+ const int len = strlen(str);
+ int sent, b;
+
+ /* first, send a 4-byte length indicator */
+ b = write(socket, &len, sizeof(len));
+ if (b <= 0)
+ return -1;
+
+ sent = SendData(socket, str, len);
+ assert(sent == len);
+ return sent;
+}
+
+
+int
+ReceiveString(int socket, char *str, int maxLen)
+{
+ int len, received, b;
+
+ /* first, read 4 bytes to see how long of string to receive */
+ b = read(socket, &len, sizeof(len));
+ if (b <= 0)
+ return -1;
+
+ assert(len <= maxLen); /* XXX fix someday */
+ assert(len >= 0);
+ received = ReceiveData(socket, str, len);
+ assert(received != -1);
+ assert(received == len);
+ str[len] = 0;
+ return received;
+}