/* Linux and Android Graphics Stack

  Alison Chaiken
  alchaiken@gmail.com
  http://www.exerciseforthereader.org/, http://she-devel.com
  8/9/2011

  Docs: 
  =======

  Graphviz: http://www.graphviz.org/Documentation.php

  OpenGLES, EGL: http://www.khronos.org/

  X11: http://www.bitwiz.org.uk/s/how-dri-and-drm-work.html

  http://wiki.x.org/wiki/Development/Documentation/HowVideoCardsWork

  GEM and TTM: https://lwn.net/Articles/283793/, http://www.x.org/wiki/ttm

  http://yangman.ca/blog/2009/10/linux-graphics-driver-stack-explained/

  Android: Sasken Communications Technologies' "Graphics in Android," http://www.scribd.com/doc/52905278/Graphics-in-Android-an-Introduction
  http://developer.android.com/sdk/ndk/index.html
  file:///opt/android-ndk-r6/docs/STABLE-APIS.html

   Create SVG file: dot -Tsvg GraphicsStack.dot -o GraphicsStack.svg
   View with browser, or from command-line: eog GraphicsStack.svg
*/

digraph "parallel_graphics_stacks" {
 graph [fontsize=12,label="Android and Linux Graphics Stacks\n\n",labelfontsize=24,labelloc="t"];
// ,rankdir="LR"
 node [fontsize=10,fillcolor=thistle,style=filled,color=lightslateblue];
 edge [fontsize=12,color=springgreen3];

//top-level nodes
{ node [fillcolor=pink,style=filled,color=pink]
  xRoot [label="Linux program\n(X11 client)"];
 aRoot [label="Android app"];
}
//Note [label="Need new modification or wrapping",fontcolor="red",style=""];
//{rank = source xRoot; aRoot; Note}  
{rank = source xRoot; aRoot}  // breaks node coloration declaration if it precedes it

//unused Android nodes  
/* 
  WindowManager [label="WindowManager"];
  SurfaceHeapManager [label="SurfaceHeapManager"];
  MemoryDealer [label="MemoryDealer"];
  renderscript [label="renderscript"];
*/

SurfaceFlingerIn [label="SurfaceFlinger "];
X11In [label="X11 server"];
{ rank=same; SurfaceFlingerIn; X11In }

  EGL [label="EGL (embedded)\nor GLX (desktop)"];
//  EGLwrapper [label="EGL wrapper",fontcolor=red];
  aEGL [label="EGL",fontcolor=black];
  {rank = same; EGL; aEGL} 

  DRI2in [label="DRI2 "];
  gralloc[label="gralloc",fontcolor=black];
  {rank = same; DRI2in; gralloc}

  OpenGLES [label="OpenGLES (embedded)\nor OpenGL (desktop)"];
  aOpenGLES [label="OpenGLES "];
  EXAin [label="EXA (native X11)\nor OpenVG"];
  UXAin [label="UXA (Intel X11)"];
  Skia [label="Skia"];
  agl [label="agl"];
{rank = same; OpenGLES; EXAin; UXAin; aOpenGLES;Skia; agl}

{ node [fillcolor=palegoldenrod,style=filled]
  TTM [label="TTM DRM KM"];
  GEM [label="GEM DRM KM"];
  GPU [label="GPU KM"];
  aDRM [label="DRM KM"];
  aGPU [label="GPU KM"];
}
{rank = same; TTM; GEM; GPU; aDRM; aGPU}  // breaks node coloration declaration if it precedes it

  DRI2out [label="DRI2 "];
  UXAout [label="UXA "];
  aEGLout [label="EGL",fontcolor=black];
  SurfaceFlingerOut [label="SurfaceFlinger "];
  Compositor [label="Compositor\n(mutter or\nkwin)"];
{ rank = same; SurfaceFlingerOut; Compositor }
{ rank = same; DRI2out; UXAout}

  Framebuffer [label="Framebuffer"];
  aFramebuffer [label="Framebuffer"];
{rank=same; Framebuffer; aFramebuffer};

{ edge [headport=n]
    xRoot -> X11In -> EGL;
    aRoot -> SurfaceFlingerIn;
    SurfaceFlingerIn -> aEGL;
    EGL -> OpenGLES [label="3D",fontcolor=springgreen3];  
    EGL -> EXAin [label="2D",fontcolor=springgreen3,style=dashed];  
    EGL -> UXAin [label="2D",fontcolor=springgreen3,style=dashed];  
    aEGL -> aOpenGLES [label="3D",fontcolor=springgreen3];  
    aEGL -> Skia [label="2D",fontcolor=springgreen3];  
    aEGL -> agl [label="SW rendering\nfallback",fontcolor=red,style=dashed,color=red]
    OpenGLES -> DRI2in [label="3D",fontcolor=springgreen3];
    EXAin -> DRI2in [label="2D",fontcolor=springgreen3,style=dashed];
    UXAin -> GEM [label="2D data",fontcolor=springgreen3,style=dashed];  
    UXAin -> GPU [label="2D instructions",fontcolor=blue,color=blue,style=dashed]; 
    aOpenGLES -> gralloc;
    agl -> gralloc;
    Skia -> gralloc;
    aDRM -> aEGLout -> SurfaceFlingerOut;
}
	
// double-headed
edge [headport=w] TTM -> GPU;
edge [headport=w] aDRM -> aGPU;
edge [headport=e] GPU-> TTM;
edge [headport=e,tailport=w,style=dashed] GEM -> GPU;
edge [headport=w,tailport=e,style=dashed] GPU-> GEM;
edge [headport=e,tailport=w] aGPU-> aDRM;

{ edge  [labelangle=-90.0,lp=8,fontcolor=blue,label="instructions",labeldistance=0,tailport=s,headport=n,color=blue,style=solid]
  DRI2in -> GPU;
  gralloc -> aGPU;
}

{ edge  [tailport=s,headport=n,label="data",distance=0,fontcolor=springgreen3,style=solid]
  DRI2in -> TTM ;
  gralloc -> aDRM;
}

{ edge [headport=n,tailport=s]
  TTM -> DRI2out [fontcolor=springgreen3]; 
  GEM -> UXAout [fontcolor=springgreen3,style=dashed]; 
}

DRI2out -> Compositor [fontcolor=springgreen3,headport=n,tailport=s,style=solid];
UXAout -> Compositor [fontcolor=springgreen3,headport=n,tailport=s,style=dashed];
Compositor -> Framebuffer [fontcolor=springgreen3,headport=n,tailport=s,style=solid];
SurfaceFlingerOut -> aFramebuffer [fontcolor=springgreen3,headport=n,tailport=s];
{ rank=same; SurfaceFlingerOut; Compositor }

}