intel_buffers.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

   LOCK_HARDWARE(intel);

   intel_batchbuffer_flush(intel->batch);

   if ( intel_fb->pf_active ) {
      swap.seqtype |= DRM_VBLANK_FLIP;

      intel_fb->pf_current_page = (((intel->sarea->pf_current_page >>
				     (intel_fb->pf_planes & 0x2)) & 0x3) + 1) %
				  intel_fb->pf_num_pages;
   }

   if (!drmCommandWriteRead(intel->driFd, DRM_I915_VBLANK_SWAP, &swap,
			    sizeof(swap))) {
      dPriv->vblSeq = swap.sequence;
      swap.sequence -= target;
      *missed_target = swap.sequence > 0 && swap.sequence <= (1 << 23);

      intel_get_renderbuffer(&intel_fb->Base, BUFFER_BACK_LEFT)->vbl_pending =
	 intel_get_renderbuffer(&intel_fb->Base,
				BUFFER_FRONT_LEFT)->vbl_pending =
	 dPriv->vblSeq;

      if (swap.seqtype & DRM_VBLANK_FLIP) {
	 intel_flip_renderbuffers(intel_fb);
	 intel_draw_buffer(&intel->ctx, intel->ctx.DrawBuffer);
      }

      ret = GL_TRUE;
   } else {
      if (swap.seqtype & DRM_VBLANK_FLIP) {
	 intel_fb->pf_current_page = ((intel->sarea->pf_current_page >>
					(intel_fb->pf_planes & 0x2)) & 0x3) %
				     intel_fb->pf_num_pages;
      }

      ret = GL_FALSE;
   }

   UNLOCK_HARDWARE(intel);

   return ret;
}
  
void
intelSwapBuffers(__DRIdrawablePrivate * dPriv)
{
   __DRIscreenPrivate *psp = dPriv->driScreenPriv;

   if (dPriv->driContextPriv && dPriv->driContextPriv->driverPrivate) {
      GET_CURRENT_CONTEXT(ctx);
      struct intel_context *intel;

      if (ctx == NULL)
	 return;

      intel = intel_context(ctx);

      if (ctx->Visual.doubleBufferMode) {
	 GLboolean missed_target;
	 struct intel_framebuffer *intel_fb = dPriv->driverPrivate;
	 int64_t ust;
         
	 _mesa_notifySwapBuffers(ctx);  /* flush pending rendering comands */

         if (!intelScheduleSwap(dPriv, &missed_target)) {
	    driWaitForVBlank(dPriv, &missed_target);

	    /*
	     * Update each buffer's vbl_pending so we don't get too out of
	     * sync
	     */
	    intel_get_renderbuffer(&intel_fb->Base,
				   BUFFER_BACK_LEFT)->vbl_pending = 
		    intel_get_renderbuffer(&intel_fb->Base,
					   BUFFER_FRONT_LEFT)->vbl_pending =
		    dPriv->vblSeq;
	    if (!intelPageFlip(dPriv)) {
	       intelCopyBuffer(dPriv, NULL);
	    }
	 }

	 intel_fb->swap_count++;
	 (*psp->systemTime->getUST) (&ust);
	 if (missed_target) {
	    intel_fb->swap_missed_count++;
	    intel_fb->swap_missed_ust = ust - intel_fb->swap_ust;
	 }

	 intel_fb->swap_ust = ust;
      }
   }
   else {
      /* XXX this shouldn't be an error but we can't handle it for now */
      fprintf(stderr, "%s: drawable has no context!\n", __FUNCTION__);
   }
}

void
intelCopySubBuffer(__DRIdrawablePrivate * dPriv, int x, int y, int w, int h)
{
   if (dPriv->driContextPriv && dPriv->driContextPriv->driverPrivate) {
      struct intel_context *intel =
         (struct intel_context *) dPriv->driContextPriv->driverPrivate;
      GLcontext *ctx = &intel->ctx;

      if (ctx->Visual.doubleBufferMode) {
         drm_clip_rect_t rect;
         rect.x1 = x + dPriv->x;
         rect.y1 = (dPriv->h - y - h) + dPriv->y;
         rect.x2 = rect.x1 + w;
         rect.y2 = rect.y1 + h;
         _mesa_notifySwapBuffers(ctx);  /* flush pending rendering comands */
         intelCopyBuffer(dPriv, &rect);
      }
   }
   else {
      /* XXX this shouldn't be an error but we can't handle it for now */
      fprintf(stderr, "%s: drawable has no context!\n", __FUNCTION__);
   }
}


/**
 * Update the hardware state for drawing into a window or framebuffer object.
 *
 * Called by glDrawBuffer, glBindFramebufferEXT, MakeCurrent, and other
 * places within the driver.
 *
 * Basically, this needs to be called any time the current framebuffer
 * changes, the renderbuffers change, or we need to draw into different
 * color buffers.
 */
void
intel_draw_buffer(GLcontext * ctx, struct gl_framebuffer *fb)
{
   struct intel_context *intel = intel_context(ctx);
   struct intel_region *colorRegions[MAX_DRAW_BUFFERS], *depthRegion = NULL;
   struct intel_renderbuffer *irbDepth = NULL, *irbStencil = NULL;
   int front = 0;               /* drawing to front color buffer? */

   if (!fb) {
      /* this can happen during the initial context initialization */
      return;
   }

   /* Do this here, note core Mesa, since this function is called from
    * many places within the driver.
    */
   if (ctx->NewState & (_NEW_BUFFERS | _NEW_COLOR | _NEW_PIXEL)) {
      /* this updates the DrawBuffer->_NumColorDrawBuffers fields, etc */
      _mesa_update_framebuffer(ctx);
      /* this updates the DrawBuffer's Width/Height if it's a FBO */
      _mesa_update_draw_buffer_bounds(ctx);
   }

   if (fb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
      /* this may occur when we're called by glBindFrameBuffer() during
       * the process of someone setting up renderbuffers, etc.
       */
      /*_mesa_debug(ctx, "DrawBuffer: incomplete user FBO\n");*/
      return;
   }

   if (fb->Name)
      intel_validate_paired_depth_stencil(ctx, fb);

   /* If the batch contents require looping over cliprects, flush them before
    * we go changing which cliprects get referenced when that happens.
    */
   if (intel->batch->cliprect_mode == LOOP_CLIPRECTS)
      intel_batchbuffer_flush(intel->batch);

   /*
    * How many color buffers are we drawing into?
    */
   if (fb->_NumColorDrawBuffers == 0) {
      /* writing to 0  */
      FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_TRUE);
      colorRegions[0] = NULL;

      if (fb->Name != 0)
	 intelSetRenderbufferClipRects(intel);
   } else if (fb->_NumColorDrawBuffers > 1) {
       int i;
       struct intel_renderbuffer *irb;
       FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_FALSE);

       if (fb->Name != 0)
           intelSetRenderbufferClipRects(intel);
       for (i = 0; i < fb->_NumColorDrawBuffers; i++) {
           irb = intel_renderbuffer(fb->_ColorDrawBuffers[i]);
           colorRegions[i] = (irb && irb->region) ? irb->region : NULL;
       }
   }
   else {
      /* draw to exactly one color buffer */
      /*_mesa_debug(ctx, "Hardware rendering\n");*/
      FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_FALSE);
      if (fb->_ColorDrawBufferIndexes[0] == BUFFER_FRONT_LEFT) {
         front = 1;
      }

      /*
       * Get the intel_renderbuffer for the colorbuffer we're drawing into.
       * And set up cliprects.
       */
      if (fb->Name == 0) {
	 /* drawing to window system buffer */
	 if (front) {
	    intelSetFrontClipRects(intel);
	    colorRegions[0] = intel_get_rb_region(fb, BUFFER_FRONT_LEFT);
	 }
	 else {
	    intelSetBackClipRects(intel);
	    colorRegions[0]= intel_get_rb_region(fb, BUFFER_BACK_LEFT);
	 }
      }
      else {
	 /* drawing to user-created FBO */
	 struct intel_renderbuffer *irb;
	 intelSetRenderbufferClipRects(intel);
	 irb = intel_renderbuffer(fb->_ColorDrawBuffers[0]);
	 colorRegions[0] = (irb && irb->region) ? irb->region : NULL;
      }
   }

   /* Update culling direction which changes depending on the
    * orientation of the buffer:
    */
   if (ctx->Driver.FrontFace)
      ctx->Driver.FrontFace(ctx, ctx->Polygon.FrontFace);
   else
      ctx->NewState |= _NEW_POLYGON;

   if (!colorRegions[0]) {
      FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_TRUE);
   }
   else {
      FALLBACK(intel, INTEL_FALLBACK_DRAW_BUFFER, GL_FALSE);
   }

   /***
    *** Get depth buffer region and check if we need a software fallback.
    *** Note that the depth buffer is usually a DEPTH_STENCIL buffer.
    ***/
   if (fb->_DepthBuffer && fb->_DepthBuffer->Wrapped) {
      irbDepth = intel_renderbuffer(fb->_DepthBuffer->Wrapped);
      if (irbDepth && irbDepth->region) {
         FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
         depthRegion = irbDepth->region;
      }
      else {
         FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_TRUE);
         depthRegion = NULL;
      }
   }
   else {
      /* not using depth buffer */
      FALLBACK(intel, INTEL_FALLBACK_DEPTH_BUFFER, GL_FALSE);
      depthRegion = NULL;
   }

   /***
    *** Stencil buffer
    *** This can only be hardware accelerated if we're using a
    *** combined DEPTH_STENCIL buffer (for now anyway).
    ***/
   if (fb->_StencilBuffer && fb->_StencilBuffer->Wrapped) {
      irbStencil = intel_renderbuffer(fb->_StencilBuffer->Wrapped);
      if (irbStencil && irbStencil->region) {
         ASSERT(irbStencil->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT);
         FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
         /* need to re-compute stencil hw state */
	 if (ctx->Driver.Enable != NULL)
	    ctx->Driver.Enable(ctx, GL_STENCIL_TEST, ctx->Stencil.Enabled);
	 else
	    ctx->NewState |= _NEW_STENCIL;
         if (!depthRegion)
            depthRegion = irbStencil->region;
      }
      else {
         FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_TRUE);
      }
   }
   else {
      /* XXX FBO: instead of FALSE, pass ctx->Stencil.Enabled ??? */
      FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
      /* need to re-compute stencil hw state */
      if (ctx->Driver.Enable != NULL)
	 ctx->Driver.Enable(ctx, GL_STENCIL_TEST, ctx->Stencil.Enabled);
      else
	 ctx->NewState |= _NEW_STENCIL;
   }

   /*
    * Update depth test state
    */
   if (ctx->Driver.Enable) {
      if (ctx->Depth.Test && fb->Visual.depthBits > 0) {
	 ctx->Driver.Enable(ctx, GL_DEPTH_TEST, GL_TRUE);
      } else {
	 ctx->Driver.Enable(ctx, GL_DEPTH_TEST, GL_FALSE);
      }
   } else {
      ctx->NewState |= _NEW_DEPTH;
   }

   intel->vtbl.set_draw_region(intel, colorRegions, depthRegion, 
	fb->_NumColorDrawBuffers);

   /* update viewport since it depends on window size */
   if (ctx->Driver.Viewport) {
      ctx->Driver.Viewport(ctx, ctx->Viewport.X, ctx->Viewport.Y,
			   ctx->Viewport.Width, ctx->Viewport.Height);
   } else {
      ctx->NewState |= _NEW_VIEWPORT;
   }

   /* Set state we know depends on drawable parameters:
    */
   if (ctx->Driver.Scissor)
      ctx->Driver.Scissor(ctx, ctx->Scissor.X, ctx->Scissor.Y,
			  ctx->Scissor.Width, ctx->Scissor.Height);
   intel->NewGLState |= _NEW_SCISSOR;

   if (ctx->Driver.DepthRange)
      ctx->Driver.DepthRange(ctx,
			     ctx->Viewport.Near,
			     ctx->Viewport.Far);
}


static void
intelDrawBuffer(GLcontext * ctx, GLenum mode)
{
   intel_draw_buffer(ctx, ctx->DrawBuffer);
}


static void
intelReadBuffer(GLcontext * ctx, GLenum mode)
{
   if (ctx->ReadBuffer == ctx->DrawBuffer) {
      /* This will update FBO completeness status.
       * A framebuffer will be incomplete if the GL_READ_BUFFER setting
       * refers to a missing renderbuffer.  Calling glReadBuffer can set
       * that straight and can make the drawing buffer complete.
       */
      intel_draw_buffer(ctx, ctx->DrawBuffer);
   }
   /* Generally, functions which read pixels (glReadPixels, glCopyPixels, etc)
    * reference ctx->ReadBuffer and do appropriate state checks.
    */
}


void
intelInitBufferFuncs(struct dd_function_table *functions)
{
   functions->Clear = intelClear;
   functions->DrawBuffer = intelDrawBuffer;
   functions->ReadBuffer = intelReadBuffer;
}