wait for client

.gitignore

@@ -2,7 +2,7 @@
 image.ppm
 
 # binary
-flark
+snoopy
 
 # CMake
 # https://github.com/github/gitignore/blob/master/CMake.gitignore

CMakeLists.txt

@@ -1,11 +1,11 @@
 cmake_minimum_required(VERSION 3.10)
 
-project(flark)
+project(snoopy)
 
-file(GLOB flark_src
+file(GLOB snoopy_src
     "src/*.h"
     "src/*.cpp"
 )
 
-add_executable(flark ${flark_src})
+add_executable(snoopy ${snoopy_src})
 

README.md

@@ -1,11 +1,9 @@
-# Flark
+# snoopy
 
-Ray tracing rendering experiments
+Networked fantasy telescope
 
-https://raytracing.github.io/
+Originally based on https://raytracing.github.io/
 
-Produced PPM images can be converted to PNG with `imagemagick`:
+Original repository at https://github.com/ktyldev/flark
 
-```
+https://www.linuxhowtos.org/C_C++/socket.htm
-convert image.ppm image.png
-```

src/main.cpp

@@ -8,6 +8,13 @@
 
 #include <iostream>
 
+#include <string.h>
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
 const double ASPECT_RATIO = 16.0 / 9.0;
 const int WIDTH = 1920;
 const int HEIGHT = static_cast<int>(WIDTH / ASPECT_RATIO);
@@ -112,8 +119,62 @@ hittable_list random_scene()
     return world;
 }
 
+void error(const char* message)
+{
+    perror(message);
+    exit(1);
+}
+
+void wait_for_client()
+{
+    int sockfd, newsockfd;
+    struct sockaddr_in serv_addr, cli_addr;
+    socklen_t clilen;
+
+    // open socket and await connection from client
+    sockfd = socket(AF_INET, SOCK_STREAM, 0);
+    if (sockfd < 0)
+    {
+        error("ERROR creating socket");
+    }
+
+    bzero((char*)&serv_addr, sizeof(serv_addr));
+
+    // we successfully created the socket, configure it for binding
+    serv_addr.sin_family = AF_INET;
+    serv_addr.sin_addr.s_addr = INADDR_ANY;
+    serv_addr.sin_port = htons(64999);  // convert number from host to network byte order
+
+    // bind the socket
+    if (bind(sockfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) < 0)
+    {
+        error("ERROR binding socket");
+    }
+
+    // successfully bound socket, start listening for connections
+    listen(sockfd, 5);
+    clilen = sizeof(cli_addr);
+
+    newsockfd = accept(sockfd, (struct sockaddr*)&cli_addr, &clilen);
+    if (newsockfd < 0)
+    {
+        error("ERROR accepting client");
+    }
+
+    printf("got a connection!\n");
+
+    // close sockets we opened
+    close(newsockfd);
+    close(sockfd);
+
+    // once connection is acquired, exit
+    exit(0);
+}
+
 int main()
 {
+    wait_for_client();
+
     std::cout << "P3\n" << WIDTH << ' ' << HEIGHT << "\n255\n";
 
     hittable_list world = random_scene();

telescope.md

@@ -0,0 +1,21 @@
+fantasy telescope idea
+
+use rti1w as a base
+
+* [ ] move rendering out of main.cpp
+* [x] server waits for connection
+* [x] client establishes connection
+* [ ] client sends receiving port to server
+* [ ] client application sends command to send image
+* [ ] server receives imaging command
+* [ ] server renders image
+* [ ] server sends image data stream to client
+* [ ] client application receives image
+* [ ] client requests resend of lost packets
+* [ ] client displays image
+* [ ] client saves image to file
+* [ ] server sends telemetry to client (what telemetry?)
+* [ ] server compresses image before sending to client
+* [ ] client specifies image parameters
+
+