Additional login in intel_draw_buffer() to check if any needed renderbuffers

are software/fallback cases.
The hardware's combined depth/stencil buffer is now treated as such
(ala GL_EXT_packed_depth_stencil).  So the depth/stencil span functions
are effectively merged.  Renderbuffers wrappers will extract the depth or
stencil values when needed.

src/mesa/drivers/dri/i915/intel_buffers.c

@@ -503,14 +503,19 @@ void intelSwapBuffers( __DRIdrawablePrivate *dPriv )
 
 /**
  * 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_renderbuffer *irb;
+   struct intel_renderbuffer *irb, *irbDepth, *irbStencil;
    struct intel_region *colorRegion, *depthRegion;
    int front = 0; /* drawing to front color buffer? */
  
@@ -586,9 +591,9 @@ intel_draw_buffer(GLcontext *ctx, struct gl_framebuffer *fb)
       ASSERT(irb);
    }
 
-   /*
-    * Get color buffer region.
-    */
+   /***
+    *** Get color buffer region.
+    ***/
    if (irb && irb->region)
       colorRegion = irb->region;
    else
@@ -602,14 +607,27 @@ intel_draw_buffer(GLcontext *ctx, struct gl_framebuffer *fb)
       intel_region_reference(&intel->draw_region, colorRegion);
    }
 
-   /*
-    * Get depth buffer region
-    */
-   irb = intel_renderbuffer(fb->_DepthBuffer);
-   if (irb && irb->region)
-      depthRegion = irb->region;
-   else
+
+   /***
+    *** Get depth buffer region and check if we need a software fallback.
+    *** Note the BUFFER_DEPTH attachment is usually a DEPTH_STENCIL buffer.
+    ***/
+   irbDepth = intel_renderbuffer(fb->Attachment[BUFFER_DEPTH].Renderbuffer);
+   if (irbDepth) {
+      if (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;
+   }
 
    /*
     * Unbind old depth region, bind new region
@@ -619,6 +637,23 @@ intel_draw_buffer(GLcontext *ctx, struct gl_framebuffer *fb)
       intel_region_reference(&intel->depth_region, depthRegion);
    }
 
+
+   /***
+    *** Stencil buffer
+    *** This can only be hardware accelerated if we're using a
+    *** combined DEPTH_STENCIL buffer (for now anyway).
+    ***/
+   irbStencil =intel_renderbuffer(fb->Attachment[BUFFER_STENCIL].Renderbuffer);
+   if (irbStencil) {
+      if (irbStencil == irbDepth && irbStencil->region)
+         FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
+      else
+         FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_TRUE);
+   }
+   else {
+      FALLBACK(intel, INTEL_FALLBACK_STENCIL_BUFFER, GL_FALSE);
+   }
+
    intel->vtbl.set_draw_region( intel, colorRegion, depthRegion );
 }
 

src/mesa/drivers/dri/i915/intel_context.c

@@ -532,8 +532,9 @@ GLboolean intelMakeCurrent(__DRIcontextPrivate *driContextPriv,
 
       _mesa_make_current(&intel->ctx, drawFb, readFb);
 
-      intel->ctx.Driver.DrawBuffer( &intel->ctx, intel->ctx.Color.DrawBuffer[0] );
-   } else {
+      intel_draw_buffer(&intel->ctx, drawFb);
+   }
+   else {
       _mesa_make_current(NULL, NULL, NULL);
    }
 

src/mesa/drivers/dri/i915/intel_context.h

@@ -57,8 +57,10 @@ typedef void (*intel_point_func)(struct intel_context *, intelVertex *);
 
 #define INTEL_FALLBACK_DRAW_BUFFER	 0x1
 #define INTEL_FALLBACK_READ_BUFFER	 0x2
-#define INTEL_FALLBACK_USER		 0x4
-#define INTEL_FALLBACK_RENDERMODE	 0x8
+#define INTEL_FALLBACK_DEPTH_BUFFER      0x4
+#define INTEL_FALLBACK_STENCIL_BUFFER    0x8
+#define INTEL_FALLBACK_USER		 0x10
+#define INTEL_FALLBACK_RENDERMODE	 0x20
 
 extern void intelFallback( struct intel_context *intel, GLuint bit, GLboolean mode );
 #define FALLBACK( intel, bit, mode ) intelFallback( intel, bit, mode )

src/mesa/drivers/dri/i915/intel_fbo.c

@@ -35,6 +35,7 @@
 #include "texformat.h"
 
 #include "intel_context.h"
+#include "intel_buffers.h"
 #include "intel_bufmgr.h"
 #include "intel_fbo.h"
 #include "intel_mipmap_tree.h"
@@ -190,14 +191,14 @@ intel_alloc_renderbuffer_storage(GLcontext *ctx, struct gl_renderbuffer *rb,
    case GL_DEPTH_COMPONENT24:
    case GL_DEPTH_COMPONENT32:
       rb->InternalFormat = GL_DEPTH24_STENCIL8_EXT;
-      rb->DataType = GL_UNSIGNED_INT;
+      rb->DataType = GL_UNSIGNED_INT_24_8_EXT;
       rb->DepthBits = 24;
       cpp = 4;
       break;
    case GL_DEPTH_STENCIL_EXT:
    case GL_DEPTH24_STENCIL8_EXT:
       rb->InternalFormat = GL_DEPTH24_STENCIL8_EXT;
-      rb->DataType = GL_UNSIGNED_INT;
+      rb->DataType = GL_UNSIGNED_INT_24_8_EXT;
       rb->DepthBits = 24;
       rb->StencilBits = 8;
       cpp = 4;
@@ -336,7 +337,7 @@ intel_create_renderbuffer(GLenum intFormat, GLsizei width, GLsizei height,
       irb->Base._BaseFormat = GL_DEPTH_STENCIL_EXT;
       irb->Base.DepthBits = 24;
       irb->Base.StencilBits = 8;
-      irb->Base.DataType = GL_UNSIGNED_INT;
+      irb->Base.DataType = GL_UNSIGNED_INT_24_8_EXT;
       cpp = 4;
       break;
    default:
@@ -409,7 +410,7 @@ intel_bind_framebuffer(GLcontext *ctx, GLenum target,
    _mesa_debug(ctx, "%s %d\n", __FUNCTION__, fb->Name);
 
    if (target == GL_FRAMEBUFFER_EXT || target == GL_DRAW_FRAMEBUFFER_EXT) {
-      ctx->Driver.DrawBuffer(ctx, 0); /* second param is ignored */
+      intel_draw_buffer(ctx, fb);
       /* Integer depth range depends on depth buffer bits */
       ctx->Driver.DepthRange(ctx, ctx->Viewport.Near, ctx->Viewport.Far);
    }
@@ -432,7 +433,7 @@ intel_framebuffer_renderbuffer(GLcontext *ctx,
                fb->Name, rb->Name);
 
    _mesa_framebuffer_renderbuffer(ctx, fb, attachment, rb);
-   ctx->Driver.DrawBuffer(ctx, 0); /* second param is ignored */
+   intel_draw_buffer(ctx, fb);
 }
 
 
@@ -531,7 +532,7 @@ intel_renderbuffer_texture(GLcontext *ctx,
    intel_image = intel_texture_image(newImage);
    intel_region_reference(&irb->region, intel_image->mt->region);
 
-   ctx->Driver.DrawBuffer(ctx, 0); /* second param is ignored */
+   intel_draw_buffer(ctx, fb);
 }
 
 

src/mesa/drivers/dri/i915/intel_screen.c

@@ -270,8 +270,8 @@ static GLboolean intelCreateBuffer( __DRIscreenPrivate *driScrnPriv,
       if (mesaVis->depthBits == 24 && mesaVis->stencilBits == 8) {
          /* combined depth/stencil buffer */
          struct intel_renderbuffer *depthStencilRb
-            = intel_create_renderbuffer(/**GL_DEPTH24_STENCIL8_EXT,**/
-                                        GL_DEPTH_COMPONENT24,
+            = intel_create_renderbuffer(
+                                        GL_DEPTH24_STENCIL8_EXT,
                                         screen->width, screen->height,
                                         screen->depth.offset,
                                         screen->depth.pitch,
@@ -280,17 +280,6 @@ static GLboolean intelCreateBuffer( __DRIscreenPrivate *driScrnPriv,
          intel_set_span_functions(&depthStencilRb->Base);
          /* note: bind RB to two attachment points */
          _mesa_add_renderbuffer(fb, BUFFER_DEPTH, &depthStencilRb->Base);
-#if 1
-         /* XXX TEMP: separate stencil */
-         depthStencilRb
-            = intel_create_renderbuffer(GL_STENCIL_INDEX8_EXT,
-                                        screen->width, screen->height,
-                                        screen->depth.offset,
-                                        screen->depth.pitch,
-                                        screen->cpp, /* 4! */
-                                        screen->depth.map);
-         intel_set_span_functions(&depthStencilRb->Base);
-#endif
          _mesa_add_renderbuffer(fb, BUFFER_STENCIL, &depthStencilRb->Base);
       }
       else if (mesaVis->depthBits == 16) {

src/mesa/drivers/dri/i915/intel_span.c

@@ -110,8 +110,9 @@
 
 #define LOCAL_STENCIL_VARS LOCAL_DEPTH_VARS 
 
-/* 16 bit depthbuffer functions.
- */
+/**
+ ** 16-bit depthbuffer functions.
+ **/
 #define WRITE_DEPTH( _x, _y, d ) \
    ((GLushort *)buf)[(_x) + (_y) * pitch] = d;
 
@@ -123,22 +124,31 @@
 #include "depthtmp.h"
 
 
-/* 24/8 bit interleaved depth/stencil functions
- */
+/**
+ ** 24/8-bit interleaved depth/stencil functions
+ ** Note: we're actually reading back combined depth+stencil values.
+ ** The wrappers in main/depthstencil.c are used to extract the depth
+ ** and stencil values.
+ **/
+/* Change ZZZS -> SZZZ */
 #define WRITE_DEPTH( _x, _y, d ) {				\
-   GLuint tmp = ((GLuint *)buf)[(_x) + (_y) * pitch];		\
-   tmp &= 0xff000000;						\
-   tmp |= (d) & 0xffffff;					\
+   GLuint tmp = ((d) >> 8) | ((d) << 24);			\
    ((GLuint *)buf)[(_x) + (_y) * pitch] = tmp;			\
 }
 
-#define READ_DEPTH( d, _x, _y )					\
-   d = ((GLuint *)buf)[(_x) + (_y) * pitch] & 0xffffff;
-
+/* Change SZZZ -> ZZZS */
+#define READ_DEPTH( d, _x, _y ) {				\
+   GLuint tmp = ((GLuint *)buf)[(_x) + (_y) * pitch];		\
+   d = (tmp << 8) | (tmp >> 24);				\
+}
 
 #define TAG(x) intel##x##_z24_s8
 #include "depthtmp.h"
 
+
+/**
+ ** 8-bit stencil function (XXX FBO: This is obsolete)
+ **/
 #define WRITE_STENCIL( _x, _y, d ) {				\
    GLuint tmp = ((GLuint *)buf)[(_x) + (_y) * pitch];		\
    tmp &= 0xffffff;						\
@@ -278,10 +288,7 @@ void intelSpanRenderStart( GLcontext *ctx )
       }
    }
 
-#if 1
-   /* XXX FBO: enable this code when old DRI screen mappings go away */
    intel_map_unmap_buffers(intel, GL_TRUE);
-#endif
 }
 
 /**
@@ -310,14 +317,12 @@ void intelSpanRenderFinish( GLcontext *ctx )
       }
    }
 
-#if 1
-   /* XXX FBO: enable this code when old DRI screen mappings go away */
    intel_map_unmap_buffers(intel, GL_FALSE);
-#endif
 
    UNLOCK_HARDWARE( intel );
 }
 
+
 void intelInitSpanFuncs( GLcontext *ctx )
 {
    struct swrast_device_driver *swdd = _swrast_GetDeviceDriverReference(ctx);
@@ -326,6 +331,10 @@ void intelInitSpanFuncs( GLcontext *ctx )
 }
 
 
+/**
+ * Plug in appropriate span read/write functions for the given renderbuffer.
+ * These are used for the software fallbacks.
+ */
 void
 intel_set_span_functions(struct gl_renderbuffer *rb)
 {