1 # 2 # This work has been (or is hereby) released into the public domain by 3 # its author, Karl J. Runge <runge (at] karlrunge.com>. This applies worldwide. 4 # 5 # In case this is not legally possible: Karl J. Runge grants anyone the 6 # right to use this work for any purpose, without any conditions, unless 7 # such conditions are required by law. 8 # 9 10 INTRO: 11 ------ 12 13 This is a "patch" to make x11vnc/libvncserver work with TurboVNC: 14 15 http://www.virtualgl.org/About/TurboVNC 16 http://www.karlrunge.com/x11vnc/faq.html#faq-turbovnc 17 18 It is very experimental/kludgy. Not all TurboVNC features may be enabled. 19 We are currently evaluating whether TurboVNC support should be officially 20 put into x11vnc/libvncserver. 21 22 TurboVNC is an optimized VNC for fast refresh rates on fast networks. 23 24 It does pretty well on good broadband as well. But it is not as fast 25 as regular TightVNC on slow links. 26 27 28 TURBOJPEG: 29 --------- 30 31 TurboVNC uses the TurboJPEG library based on a fast proprietary JPEG 32 implementation. You will need to download it from the VirtualGL 33 sourceforge site: 34 35 http://sourceforge.net/project/showfiles.php?group_id=117509&package_id=166100 36 37 Either install it or simply unpack the .deb or .rpm file into a directory. 38 39 N.B. you can unpack a .deb via 'ar x package.deb' and the extracting 40 from the data.tar.gz file. rpm2cpio can be used to unpack .rpm's. 41 42 43 QUICK-START: 44 ------------ 45 46 For those in a hurry: 47 48 cd x11vnc-x.y.z/x11vnc/misc/turbovnc 49 ./apply_turbovnc 50 cd ../../.. 51 env LDFLAGS='-L/DIR -Xlinker --rpath=/DIR' ./configure 52 make AM_LDFLAGS='-lturbojpeg' 53 54 where you replace /DIR with your directory containing libturbojpeg.so. 55 56 57 PATCHING AND BUILDING: 58 ---------------------- 59 60 After unpacking your x11vnc-x.y.z.tar.gz tarball cd to the 61 x11vnc-x.y.z/x11vnc/misc/turbovnc (where this README file is) and from 62 that directory run: 63 64 ./apply_turbovnc 65 66 that will modify files in the libvncserver and x11vnc directories above 67 this directory. (To undo these changes run: ./undo_turbovnc) The input 68 sources, tight.c and turbojpeg.h are from the TurboVNC source package. 69 70 After applying, go back to the top level source directory and run: 71 72 env LDFLAGS='-L/path/to/turbojpeg -Xlinker --rpath=/path/to/turbojpeg' ./configure 73 74 where the turbojpeg library is: 75 76 /path/to/turbojpeg/libturbojpeg.so 77 78 (change /path/to/turbojpeg to the directory where you installed or 79 unpacked it.) 80 81 If you are not using gnu gcc and gnu linker the options may be a little 82 different (e.g. -R instead of -Xlinker --rpath). 83 84 If you need additional ./configure options or env. var. settings, 85 add them too. 86 87 88 Next, run this make command: 89 90 make AM_LDFLAGS='-lturbojpeg' 91 92 This is a hack and may not always work, if it doesn't edit x11vnc/Makefile 93 and add '-lturbojpeg' to the LIBS variable. 94 95 This should create a binary: 96 97 ./x11vnc/x11vnc 98 99 that supports VirtualGL's TurboVNC. 100 101 You will need a TurboVNC viewer, you can get one here: 102 103 http://sourceforge.net/project/showfiles.php?group_id=117509&package_id=128130 104 105 Let us know how it goes. 106 107 108 PERFORMANCE: 109 ------------ 110 111 Note that x11vnc has to read the display's screen pixels from the 112 graphics card memory. This can be slow, e.g. 10 MB/sec. 113 114 There is not a big need for graphics card manufacturers to optimize the 115 read rate; the write rate is the one they optimize greatly. 116 117 http://www.karlrunge.com/x11vnc/#limitations 118 119 If you run x11vnc and see lines like this: 120 121 28/02/2009 00:52:07 Autoprobing selected port 5900 122 28/02/2009 00:52:07 fb read rate: 10 MB/sec 123 28/02/2009 00:52:07 screen setup finished. 124 125 you have a typical slow one. 126 127 Whereas if you see this: 128 129 28/02/2009 00:54:46 Autoprobing selected port 5900 130 28/02/2009 00:54:46 fb read rate: 321 MB/sec 131 28/02/2009 00:54:46 fast read: reset wait ms to: 10 132 28/02/2009 00:54:46 fast read: reset defer ms to: 10 133 28/02/2009 00:54:46 screen setup finished. 134 135 that is very fast. In such a situation you may want to dial down 136 x11vnc's delay, e.g.: -wait 5 -defer 5, or even smaller to push things 137 out more quickly. 138 139 We have only seen it this fast on Linux by using the nvidia proprietary 140 graphics drivers. The Xorg drivers are typically slow 10 MB/sec. 141 142 It will also be fast if the X server is virtual: Xvfb or Xdummy 143 since the screen pixels are stored in RAM: 144 145 http://www.karlrunge.com/x11vnc/faq.html#faq-xvfb 146 147 And it will be fast if the ShadowFB xorg.conf option is enabled (if the 148 card supports it.) 149 150 151 The point we are trying to make is that even though TurboVNC uses a 152 wicked fast JPEG implementation, and cuts out overhead in its attempt to 153 pump out as many frames per second as it can, if it is slow for x11vnc 154 to read the screen pixels in the first place then you might not even 155 notice the TurboVNC speedup. 156 157 So TurboVNC+x11vnc will be faster than TightVNC+x11vnc, but if there is 158 a large overhead/bottleneck from reading the graphics card framebuffer, 159 then the speedup will be marginal. 160
