Re: performance issue when OffscreenRenderingMode = "pbuffer"

[Jérôme Gardou]

Roderick Colenbrander a écrit :
> > I tried to play Supreme Commander using pbuffer option instead of fbo. I 
> > was quite happy with it, since I gained quite a bunch of performance (I 
> > mean, something I really COULD see), but after a while, the performance 
> > dropped dramatically, to ~4-5 fps.
> >
> > I tested quite a few thing, and I finally found that pixel bufers were 
> > not taken in account when calculating available texture memory. The game 
> > then allocated more textures, and good opengl didn't dare complain when 
> > putting them in system memory.
> >
> > Attached is a patch which should solve the problem.
> >
> > For those who are curious, try setting VideoMemorySize to 200 instead of 
> > 256. It works just like a charm.
>
> I think the basic idea of the patch is good but the calculation itself should take into account double buffering. In wine we don't use double buffering on pbuffers but we might be receiving a WGL pixel format which uses double buffering, so in that case the amount of video memory would be a factor 2 too low.
>
> Something like this would give you the double buffering capability from a d3d device:
> This->adapter->cfgs[iPixelFormat]->doubleBuffer
>
> Roderick

OK. Here is a new one, more readable I think. I'll send it to 
wine-patches once I manage to configure git-send-email :)
> From 3f20a3570a99a57c3e065f1ef93277c28fb61a4e Mon Sep 17 00:00:00 2001

From: =?utf-8?q?J=C3=A9r=C3=B4me=20Gardou?= 
Date: Sun, 25 Jan 2009 12:52:45 +0100
Subject: [PATCH] wined3d: take into account video ram that pixel buffers use.

---
 dlls/wined3d/context.c |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/dlls/wined3d/context.c b/dlls/wined3d/context.c
index da3053a..86d9db4 100644
--- a/dlls/wined3d/context.c
+++ b/dlls/wined3d/context.c
@@ -635,6 +635,7 @@ WineD3DContext *CreateContext(IWineD3DDeviceImpl *This, IWineD3DSurfaceImpl *tar
     HGLRC ctx = NULL, oldCtx;
     WineD3DContext *ret = NULL;
     int s;
+    long size = 0 ;

TRACE("(%p): Creating a %s context for render target %p\n", This, create_pbuffer ? "offscreen" : "onscreen", target);

@@ -679,6 +680,9 @@ WineD3DContext *CreateContext(IWineD3DDeviceImpl *This, IWineD3DSurfaceImpl *tar
             goto out;
         }
         ReleaseDC(win_handle, hdc_parent);
+        size = target->currentDesc.Width * target->currentDesc.Height * target->bytesPerPixel ;
+        if(This->adapter->cfgs[iPixelFormat].doubleBuffer)
+            size *= 2 ;
     } else {
         PIXELFORMATDESCRIPTOR pfd;
         int iPixelFormat;
@@ -898,6 +902,8 @@ WineD3DContext *CreateContext(IWineD3DDeviceImpl *This, IWineD3DSurfaceImpl *tar
     }
     This->frag_pipe->enable_extension((IWineD3DDevice *) This, TRUE);

+    WineD3DAdapterChangeGLRam(This, size) ;
+
     return ret;

out:
@@ -958,6 +964,7 @@ static void RemoveContextFromArray(IWineD3DDeviceImpl *This, WineD3DContext *con
  *****************************************************************************/
 void DestroyContext(IWineD3DDeviceImpl *This, WineD3DContext *context) {
     struct fbo_entry *entry, *entry2;
+    long size = 0 ;

TRACE("Destroying ctx %p\n", context);

@@ -986,11 +993,18 @@ void DestroyContext(IWineD3DDeviceImpl *This, WineD3DContext *context) {
     /* Cleanup the GL context */
     pwglMakeCurrent(NULL, NULL);
     if(context->isPBuffer) {
+        int iPixelFormat = GetPixelFormat(context->hdc) ;
+        IWineD3DSurfaceImpl* surf = (IWineD3DSurfaceImpl*) context->surface ;
         GL_EXTCALL(wglReleasePbufferDCARB(context->pbuffer, context->hdc));
         GL_EXTCALL(wglDestroyPbufferARB(context->pbuffer));
+        size = surf->currentDesc.Width * surf->currentDesc.Height * surf->bytesPerPixel ;
+        if(This->adapter->cfgs[iPixelFormat].doubleBuffer)
+            size *= 2 ;
     } else ReleaseDC(context->win_handle, context->hdc);
     pwglDeleteContext(context->glCtx);

+    WineD3DAdapterChangeGLRam(This, (-1)*size) ;
+
     HeapFree(GetProcessHeap(), 0, context->vshader_const_dirty);
     HeapFree(GetProcessHeap(), 0, context->pshader_const_dirty);
     RemoveContextFromArray(This, context);