Moved screen buffer code to seperate file.

C/Server/screenbuffer.c

@@ -0,0 +1,90 @@
+#include "screenbuffer.h"
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <fcntl.h>
+#include <linux/fb.h>
+#include <sys/mman.h>
+#include <sys/ioctl.h>
+
+int fbfd = 0;
+struct fb_var_screeninfo orig_vinfo;
+struct fb_var_screeninfo vinfo;
+struct fb_fix_screeninfo finfo;
+long int screensize = 0;
+char *fbp = 0;
+  
+
+int8_t init_frame_buffer(void)
+{
+  // Open the file for reading and writing
+  fbfd = open("/dev/fb0", O_RDWR);
+  if (!fbfd) {
+    printf("Error: cannot open framebuffer device.\n");
+    return 0;
+  }
+  printf("The framebuffer device was opened successfully.\n");
+
+  // Get variable screen information
+  if (ioctl(fbfd, FBIOGET_VSCREENINFO, &vinfo)) {
+    printf("Error reading variable information.\n");
+    return 0;
+  }
+  printf("Original %dx%d, %dbpp\n", vinfo.xres, vinfo.yres, 
+         vinfo.bits_per_pixel );
+
+  // Store for reset (copy vinfo to vinfo_orig)
+  memcpy(&orig_vinfo, &vinfo, sizeof(struct fb_var_screeninfo));
+
+  // Change variable info
+  vinfo.bits_per_pixel = 24;
+  if (ioctl(fbfd, FBIOPUT_VSCREENINFO, &vinfo)) {
+    printf("Error setting variable information.\n");
+    return 0;
+  }
+  
+  // Get fixed screen information
+  if (ioctl(fbfd, FBIOGET_FSCREENINFO, &finfo)) {
+    printf("Error reading fixed information.\n");
+    return 0;
+  }
+
+  // map fb to user mem 
+  screensize = finfo.smem_len;
+  fbp = (char*)mmap(0, 
+                    screensize, 
+                    PROT_READ | PROT_WRITE, 
+                    MAP_SHARED, 
+                    fbfd, 
+                    0);
+
+  if ((long)fbp == -1) {
+    printf("Error: Failed to mmap.\n");
+    return 0;
+  }
+  return 1;
+}
+
+
+void deinit_frame_buffer(void)
+{
+  // cleanup
+  munmap((void *)fbp, screensize);
+  if (ioctl(fbfd, FBIOPUT_VSCREENINFO, &orig_vinfo)) {
+    printf("Error re-setting variable information.\n");
+  }
+  close(fbfd);
+}
+
+void write_pixel_to_screen(uint16_t x, uint16_t y, uint16_t r, uint16_t g, uint16_t b, uint8_t a){
+  unsigned int pix_offset;
+  unsigned bpp = vinfo.bits_per_pixel / 8;
+  if(x < vinfo.xres && y < vinfo.yres){
+    pix_offset = bpp * x + y * finfo.line_length;
+    fbp[pix_offset++] = r;
+    fbp[pix_offset++] = g;
+    fbp[pix_offset] = b;
+  }
+}