<div class="gmail_quote">On Fri, Mar 11, 2011 at 2:56 PM, Keith Whitwell <<a href="mailto:keithw@vmware.com">keithw@vmware.com</a>> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <div class="im">On Fri, 2011-03-11 at 06:05 +0100, Marek Olšák wrote: > Hi, > > these 2 patches add GL_NV_texture_barrier to Mesa and Gallium, > respectively. The extension can be used for programmable > blending, where the same texture can be bound as both a sampler > and renderbuffer. The same feature exists in Direct10 and > the entry point is: > > VOID APIENTRY ResourceReadAfterWriteHazard( > __in D3D10DDI_HDEVICE hDevice, > __in D3D10DDI_HRESOURCE hResource > ) > > I have chosen the same name for Gallium: > > void (*resource_read_after_write_hazard)(struct pipe_context *, > struct pipe_resource *) > > The function is documented in the second patch. > There is a new piglit test too, called blending-in-shader. > I only have working r300g support, but I may add softpipe > if needed. </div>I support this goal, but think you've probably chosen the wrong name for the function. The call you're introducing is a method for the application to cooperate with the driver to get meaningful results when a single resource is bound for read & write at the same time. In DX10-land, ResourceReadAfterWriteHazard() is something generated internally by the runtime when a resource which was previously bound to write is being rebound to read from, ie. something like: if (ctx->is_resource_referenced(ctx, resource)) ctx->flush(ctx);