[vbox-dev] vbox 3D implementation

[DONG HE]

Hi Mikhail,

You are right. I managed to build the WDDM drivers and OpenGL driver
without any problem.
Currently my understanding is that chromium commands is a command packet
wrapper in which OpenGL state values are packed. The packer
(GuestHost\OpenGL\packer) is built as VBoxOGLpackspu.dll that VBoxOGL.dll
will use, meanwhile, there is a VBox HOST process interprets and execute
the OpenGL commands (HostServices\SharedOpenGL\unpacker).
At this point I am still unclear on some details. Can you please enlighten
me on a few questions? Really appreciate!
1) The 3D application running on guest OS creates render target (surfaces)
where the render result goes in, I wonder how the render target are handled
across the guest OS and the Host OpenGL servie that is doing the real
rendering.

2) Suppose we have a very simple D3D application which just draws a
triangle, essentially, this app goes through D3D runtime and  asks the user
mode driver to create context, allocate at least two buffers - vertex
buffer, and render surface, I feel that only the render surface buffer
creation request will go to WDDM kernel mode driver ddi function DDI
function CreateAllocation, the context and vertex buffer will convert to
OpenGL context and vertex buffer. If I am right, the kernel mode driver
allocate the render surface and pass back the address to user mode driver,
then host service gets the render target and performs rendering on it, when
the user mode driver knows the rendering is completed it informs the kernel
mode driver and DDI function render or present copies the render target to
framebuffer to finally present the result. This is my understanding to the
whole process. If I have any misunderstanding or even not close, can you
please walk me through the process how the simplest d3d app manages to draw
a triangle and finally presents on the screen?

Best regards,
Dong

On Fri, Apr 11, 2014 at 5:25 AM, Mikhail Sennikovsky <
mikhail.sennikovsky at oracle.com> wrote:

> Hi Dong,
>
> We do not use ICD SDK atm, so it should be possible to build all asutt
> using standard WDK/SDK headers/libs & tools.
> We use XPDM-complient ICD interface to implement OpenGL support on windows.
> As for D3D,  VBox WineD3D version is using VBoxOGL directly rather than
> via Opengl32 + ICD.
> WDDM incarnation of VBox D3D in particular is actually using VBoxOGL as a
> layer for packing chromium commands which are then submitted via standard
> 3D/WDDM DDI.
>
> Mikhail
>
> On Apr 11, 2014, at 7:06 AM, DONG HE <hedonghust at gmail.com> wrote:
>
> Hi Mikhail & Klaus,
>
> Thanks a lot for your information. It is very helpful.
> I had wrong impression that VBox 3D implementation is on top SVGA, which
> leaded me to the wrong place in the repository where has an uncompleted
> SVGA.
> Now I kinda have a big picture how VBox D3D&OpenGL driver works.
> src\VBox\Additions\WINNT\Graphics\Video\mp\wddm contains the wddm miniport
> driver which talks to dxgkrnl.sys
> src\VBox\Additions\WINNT\Graphics\Video\disp\wddm has the wddm d3d user
> mode driver known as VBoxDispD3D.dll. D3D states will convert to OGL states
> with the help of Wine, and eventually goes to the OpenGL drivers,
>  VBoxOGL.dll(src/VBox/Additions/common/crOpenGL).
> However, a few things are still unclear to me, such as how those modules
> interact exactly.
> And the OGL driver appears to be a Windows OpenGL ICD driver. I wonder if
> I need a Microsoft ICD SDK to build the OpenGL driver successfully. Did
> anyone manage to build the WDDM driver and OpenGL driver separately before?
>
>
> Regards,
> DONG
>
>
> >Just to get a bit more precise info on the current 3D source code
> location:
> >
> >Guest-side code is located in
> >src/VBox/Additions/common/crOpenGL
> >src/VBox/Additions/WINNT/Graphics/Video (WDDM stuff)
> >src/VBox/Additions/WINNT/Graphics/Wine_new
> >
> >Host-side code is in
> >src/VBox/HostServices/SharedOpenGL
> >
> >Gues-Host shared code is
> >src/VBox/GuestHost/OpenGL
> >
> >Hope this helps.
> >
> >Mikhail
> >
> >On 02.04.2014 21:26, Klaus Espenlaub wrote:
> >> Hi Dong,
> >>
> >> On 01.04.2014 00:53, DONG HE wrote:
> >>> Hello VBox developers,
> >>>
> >>> Recently I have great interest in figuring out how VBox implement 3D
> >>> support for D3D and OpenGL. The learning work finally can not proceed
> as
> >>> a few files are missing from the SVN trunk check-out, which
> >>> are DevVGA-SVGA3d-shared.cpp, DevVGA-SVGA3d-win.cpp
> >>> and DevVGA-SVGA3d-ogl.cpp.
> >>> I wonder why those files are truncated from the repository or if they
> >>> exist in some experimental branches? Please give me some ideas. Thanks!
> >> You're looking at totally the wrong stuff. These files are totally
> >> unrelated to the existing 3D support.
> >>
> >> Check the contents of src/VBox/HostServices/SharedOpenGL for a lot of
> >> the code (there are bits and pieces elsewhere).
> >>
> >> Note that I'm not knowing any details how the whole thing works, so
> >> asking me personally won't get you much further.
> >>
> >> Klaus
> >>> Regards,
> >>> DONG
>
>
>
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