gallium: beginnings of draw module vertex rework

Trying to put a structure in place that we can actually optimize.
Initially just implementing a passthrough mode, this will fairly soon
replace all the vertex_cache/prim_queue/shader_queue stuff that's so
hard to understand...

Split the vertex processing into a couple of distinct stages:
- Frontend
    - Prepares two lists of elements (fetch and draw) to be processed
      by the next stage.  This stage doesn't fetch or draw vertices, but
      makes the decision which to draw.  Multiple implementations of this
      will implement different strategies, currently just a vcache
      implementation.
- MiddleEnd
    - Takes the list of fetch elements, fetches them, runs the vertex
      shader, cliptest, viewport transform on them to produce a
      linear array of vertex_header vertices.
    - Passes that list of vertices, plus the draw_elements (which index
      into that list) onto the backend
- Backend
    - Either the existing primitive/clipping pipeline, or the vbuf_render
      hardware backend provided by the driver.

Currently, the middle-end is the old passthrough code, and it build hardware
vertices, not vertex_header vertices as above.  It may be that passthrough
is a special case in this respect.

1 files changed, 338 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/draw/draw_pt_vcache.c b/src/gallium/auxiliary/draw/draw_pt_vcache.c
new file mode 100644
index 0000000000..07e9f0ae5f
--- /dev/null
+++ b/src/gallium/auxiliary/draw/draw_pt_vcache.c
@@ -0,0 +1,338 @@
+/**************************************************************************
+ * 
+ * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ * 
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ * 
+ **************************************************************************/
+
+ /*
+  * Authors:
+  *   Keith Whitwell <keith@tungstengraphics.com>
+  */
+
+#include "pipe/p_util.h"
+#include "draw/draw_context.h"
+#include "draw/draw_private.h"
+//#include "draw/draw_vbuf.h"
+//#include "draw/draw_vertex.h"
+#include "draw/draw_pt.h"
+
+
+#define CACHE_MAX 32
+#define FETCH_MAX 128
+#define DRAW_MAX (16*1024)
+
+struct vcache_frontend {
+   struct draw_pt_front_end base;
+
+   ushort in[CACHE_MAX];
+   ushort out[CACHE_MAX];
+
+   ushort draw_elts[DRAW_MAX];
+   unsigned fetch_elts[FETCH_MAX];
+
+   unsigned draw_count;
+   unsigned fetch_count;
+   
+   pt_elt_func elt_func;
+   const void *elt_ptr;
+
+   struct draw_pt_middle_end *middle;
+   unsigned output_prim;
+};
+
+static void vcache_flush( struct vcache_frontend *vcache )
+{
+#if 0
+   /* Should always be true if output_prim == input_prim, otherwise
+    * not so much...
+    */
+   unsigned i;
+   for (i = 0; i < vcache->draw_count; i++) {
+      assert( vcache->fetch_elts[vcache->draw_elts[i]] == 
+              vcache->elt_func(vcache->elt_ptr, i) );
+   }
+#endif
+
+   if (vcache->draw_count)
+      vcache->middle->run( vcache->middle,
+                           vcache->output_prim,
+                           vcache->fetch_elts,
+                           vcache->fetch_count,
+                           vcache->draw_elts,
+                           vcache->draw_count );
+
+   memset(vcache->in, ~0, sizeof(vcache->in));
+   vcache->fetch_count = 0;
+   vcache->draw_count = 0;
+}
+
+static void vcache_check_flush( struct vcache_frontend *vcache )
+{
+   if ( vcache->draw_count + 6 >= DRAW_MAX ||
+        vcache->fetch_count + 4 >= FETCH_MAX )
+   {
+      vcache_flush( vcache );
+   }
+}
+
+
+static void vcache_elt( struct vcache_frontend *vcache,
+                        unsigned felt )
+{
+   // ushort felt = elt(draw, i);
+
+   ushort idx = felt % CACHE_MAX;
+
+   if (vcache->in[idx] != felt) {
+      assert(vcache->fetch_count < FETCH_MAX);
+
+      vcache->in[idx] = felt;
+      vcache->out[idx] = vcache->fetch_count;
+      vcache->fetch_elts[vcache->fetch_count++] = felt;
+   }
+
+   vcache->draw_elts[vcache->draw_count++] = vcache->out[idx];
+}
+                   
+static void vcache_triangle( struct vcache_frontend *vcache,
+                             unsigned i0,
+                             unsigned i1,
+                             unsigned i2 )
+{
+   /* TODO: encode edgeflags in draw_elts */
+   vcache_elt(vcache, i0);
+   vcache_elt(vcache, i1);
+   vcache_elt(vcache, i2);
+   vcache_check_flush(vcache);
+}
+
+static void vcache_line( struct vcache_frontend *vcache,
+                         boolean reset,
+                         unsigned i0,
+                         unsigned i1 )
+{
+   /* TODO: encode reset-line-stipple in draw_elts */
+   (void) reset;
+   vcache_elt(vcache, i0);
+   vcache_elt(vcache, i1);
+   vcache_check_flush(vcache);
+}
+
+
+static void vcache_point( struct vcache_frontend *vcache,
+                          unsigned i0 )
+{
+   vcache_elt(vcache, i0);
+   vcache_check_flush(vcache);
+}
+
+static void vcache_quad( struct vcache_frontend *vcache,
+                         unsigned i0,
+                         unsigned i1,
+                         unsigned i2,
+                         unsigned i3 )
+{
+   vcache_triangle( vcache, i0, i1, i3 );
+   vcache_triangle( vcache, i1, i2, i3 );
+}
+
+
+static void vcache_prepare( struct draw_pt_front_end *frontend,
+                            struct draw_pt_middle_end *middle )
+{
+   struct vcache_frontend *vcache = (struct vcache_frontend *)frontend;
+   vcache->middle = middle;
+   middle->prepare( middle );
+}
+
+static unsigned reduced_prim[PIPE_PRIM_POLYGON + 1] = {
+   PIPE_PRIM_POINTS,
+   PIPE_PRIM_LINES,
+   PIPE_PRIM_LINES,
+   PIPE_PRIM_LINES,
+   PIPE_PRIM_TRIANGLES,
+   PIPE_PRIM_TRIANGLES,
+   PIPE_PRIM_TRIANGLES,
+   PIPE_PRIM_TRIANGLES,
+   PIPE_PRIM_TRIANGLES,
+   PIPE_PRIM_TRIANGLES
+};
+
+
+static void vcache_run( struct draw_pt_front_end *frontend, 
+                         unsigned prim,
+                         pt_elt_func get_elt,
+                         const void *elts,
+                         unsigned count )
+{
+   struct vcache_frontend *vcache = (struct vcache_frontend *)frontend;
+   unsigned i;
+   
+   /* These are for validation only:
+    */
+   vcache->elt_func = get_elt;
+   vcache->elt_ptr = elts;
+   vcache->output_prim = reduced_prim[prim];
+
+   switch (prim) {
+   case PIPE_PRIM_POINTS:
+      for (i = 0; i < count; i ++) {
+         vcache_point( vcache,
+                       get_elt(elts, i) );
+      }
+      break;
+
+   case PIPE_PRIM_LINES:
+      for (i = 0; i+1 < count; i += 2) {
+         vcache_line( vcache, 
+                      TRUE,
+                      get_elt(elts, i + 0),
+                      get_elt(elts, i + 1));
+      }
+      break;
+
+   case PIPE_PRIM_LINE_LOOP:  
+      if (count >= 2) {
+         for (i = 1; i < count; i++) {
+            vcache_line( vcache, 
+                         i == 1, 	/* XXX: only if vb not split */
+                         get_elt(elts, i - 1),
+                         get_elt(elts, i) );
+         }
+
+         vcache_line( vcache, 
+                      0,
+                      get_elt(elts, count - 1),
+                      get_elt(elts, 0) );
+      }
+      break;
+
+   case PIPE_PRIM_LINE_STRIP:
+      for (i = 1; i < count; i++) {
+         vcache_line( vcache,
+                      i == 1,
+                      get_elt(elts, i - 1),
+                      get_elt(elts, i) );
+      }
+      break;
+
+   case PIPE_PRIM_TRIANGLES:
+      for (i = 0; i+2 < count; i += 3) {
+         vcache_triangle( vcache,
+                          get_elt(elts, i + 0),
+                          get_elt(elts, i + 1),
+                          get_elt(elts, i + 2) );
+      }
+      break;
+
+   case PIPE_PRIM_TRIANGLE_STRIP:
+      for (i = 0; i+2 < count; i++) {
+         if (i & 1) {
+            vcache_triangle( vcache,
+                             get_elt(elts, i + 1),
+                             get_elt(elts, i + 0),
+                             get_elt(elts, i + 2) );
+         }
+         else {
+            vcache_triangle( vcache,
+                             get_elt(elts, i + 0),
+                             get_elt(elts, i + 1),
+                             get_elt(elts, i + 2) );
+         }
+      }
+      break;
+
+   case PIPE_PRIM_TRIANGLE_FAN:
+      for (i = 0; i+2 < count; i++) {
+         vcache_triangle( vcache,
+                          get_elt(elts, 0),
+                          get_elt(elts, i + 1),
+                          get_elt(elts, i + 2) );
+      }
+      break;
+
+
+   case PIPE_PRIM_QUADS:
+      for (i = 0; i+3 < count; i += 4) {
+         vcache_quad( vcache,
+                      get_elt(elts, i + 0),
+                      get_elt(elts, i + 1),
+                      get_elt(elts, i + 2),
+                      get_elt(elts, i + 3));
+      }
+      break;
+
+   case PIPE_PRIM_QUAD_STRIP:
+      for (i = 0; i+3 < count; i += 2) {
+         vcache_quad( vcache,
+                      get_elt(elts, i + 2),
+                      get_elt(elts, i + 0),
+                      get_elt(elts, i + 1),
+                      get_elt(elts, i + 3));
+      }
+      break;
+
+   case PIPE_PRIM_POLYGON:
+      for (i = 0; i+2 < count; i++) {
+         vcache_triangle( vcache,
+                          get_elt(elts, i + 1),
+                          get_elt(elts, i + 2),
+                          get_elt(elts, 0));
+      }
+      break;
+
+   default:
+      assert(0);
+      break;
+   }
+   
+   vcache_flush( vcache );
+}
+
+static void vcache_finish( struct draw_pt_front_end *frontend )
+{
+   struct vcache_frontend *vcache = (struct vcache_frontend *)frontend;
+   vcache->middle->finish( vcache->middle );
+   vcache->middle = NULL;
+}
+
+static void vcache_destroy( struct draw_pt_front_end *frontend )
+{
+   FREE(frontend);
+}
+
+
+struct draw_pt_front_end *draw_pt_vcache( void )
+{
+   struct vcache_frontend *vcache = CALLOC_STRUCT( vcache_frontend );
+ 
+   vcache->base.prepare = vcache_prepare;
+   vcache->base.run     = vcache_run;
+   vcache->base.finish  = vcache_finish;
+   vcache->base.destroy = vcache_destroy;
+   
+   memset(vcache->in, ~0, sizeof(vcache->in));
+  
+   return &vcache->base;
+}