draw: Add vsplit frontend.

vsplit is based on varray.  It sets the split flags when a primitive is
splitted.  It also has support for indexed primitives.

For indexed primitives, unlike vcache, vsplit splits the primitives
instead of decomposes them.

1 files changed, 171 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/draw/draw_split_tmp.h b/src/gallium/auxiliary/draw/draw_split_tmp.h
new file mode 100644
index 0000000000..40ab0b71f1
--- /dev/null
+++ b/src/gallium/auxiliary/draw/draw_split_tmp.h
@@ -0,0 +1,171 @@
+/*
+ * Mesa 3-D graphics library
+ * Version:  7.9
+ *
+ * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * Copyright (C) 2010 LunarG Inc.
+ *
+ * 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, sublicense,
+ * 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 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 NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+static void
+FUNC(FUNC_VARS)
+{
+   unsigned first, incr;
+   LOCAL_VARS
+
+   /*
+    * prim, start, count, and max_count_{simple,loop,fan} should have been
+    * defined
+    */
+   if (0) {
+      debug_printf("%s: prim 0x%x, start %d, count %d, max_count_simple %d, "
+                   "max_count_loop %d, max_count_fan %d\n",
+                   __FUNCTION__, prim, start, count, max_count_simple,
+                   max_count_loop, max_count_fan);
+   }
+
+   draw_pt_split_prim(prim, &first, &incr);
+   /* sanitize primitive length */
+   count = draw_pt_trim_count(count, first, incr);
+   if (count < first)
+      return;
+
+   /* must be able to at least flush two complete primitives */
+   assert(max_count_simple >= first + incr &&
+          max_count_loop >= first + incr &&
+          max_count_fan >= first + incr);
+
+   /* no splitting required */
+   if (count <= max_count_simple) {
+      SEGMENT_SIMPLE(0x0, start, count);
+   }
+   else {
+      const unsigned rollback = first - incr;
+      unsigned flags = DRAW_SPLIT_AFTER, seg_start = 0, seg_max;
+
+      /*
+       * Both count and seg_max below are explicitly trimmed.  Because
+       *
+       *   seg_start = N * (seg_max - rollback) = N' * incr,
+       *
+       * we have
+       *
+       *   remaining = count - seg_start = first + N'' * incr.
+       *
+       * That is, remaining is implicitly trimmed.
+       */
+      switch (prim) {
+      case PIPE_PRIM_POINTS:
+      case PIPE_PRIM_LINES:
+      case PIPE_PRIM_LINE_STRIP:
+      case PIPE_PRIM_TRIANGLES:
+      case PIPE_PRIM_TRIANGLE_STRIP:
+      case PIPE_PRIM_QUADS:
+      case PIPE_PRIM_QUAD_STRIP:
+      case PIPE_PRIM_LINES_ADJACENCY:
+      case PIPE_PRIM_LINE_STRIP_ADJACENCY:
+      case PIPE_PRIM_TRIANGLES_ADJACENCY:
+      case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
+         seg_max =
+            draw_pt_trim_count(MIN2(max_count_simple, count), first, incr);
+         if (prim == PIPE_PRIM_TRIANGLE_STRIP ||
+             prim == PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY) {
+            /* make sure we flush even number of triangles at a time */
+            if (seg_max < count && !(((seg_max - first) / incr) & 1))
+               seg_max -= incr;
+         }
+
+         do {
+            const unsigned remaining = count - seg_start;
+
+            if (remaining > seg_max) {
+               SEGMENT_SIMPLE(flags, start + seg_start, seg_max);
+               seg_start += seg_max - rollback;
+
+               flags |= DRAW_SPLIT_BEFORE;
+            }
+            else {
+               flags &= ~DRAW_SPLIT_AFTER;
+
+               SEGMENT_SIMPLE(flags, start + seg_start, remaining);
+               seg_start += remaining;
+            }
+         } while (seg_start < count);
+         break;
+
+      case PIPE_PRIM_LINE_LOOP:
+         seg_max =
+            draw_pt_trim_count(MIN2(max_count_loop, count), first, incr);
+
+         do {
+            const unsigned remaining = count - seg_start;
+
+            if (remaining > seg_max) {
+               SEGMENT_LOOP(flags, start + seg_start, seg_max, start);
+               seg_start += seg_max - rollback;
+
+               flags |= DRAW_SPLIT_BEFORE;
+            }
+            else {
+               flags &= ~DRAW_SPLIT_AFTER;
+
+               SEGMENT_LOOP(flags, start + seg_start, remaining, start);
+               seg_start += remaining;
+            }
+         } while (seg_start < count);
+         break;
+
+      case PIPE_PRIM_TRIANGLE_FAN:
+      case PIPE_PRIM_POLYGON:
+         seg_max =
+            draw_pt_trim_count(MIN2(max_count_fan, count), first, incr);
+
+         do {
+            const unsigned remaining = count - seg_start;
+
+            if (remaining > seg_max) {
+               SEGMENT_FAN(flags, start + seg_start, seg_max, start);
+               seg_start += seg_max - rollback;
+
+               flags |= DRAW_SPLIT_BEFORE;
+            }
+            else {
+               flags &= ~DRAW_SPLIT_AFTER;
+
+               SEGMENT_FAN(flags, start + seg_start, remaining, start);
+               seg_start += remaining;
+            }
+         } while (seg_start < count);
+         break;
+
+      default:
+         assert(0);
+         break;
+      }
+   }
+}
+
+#undef FUNC
+#undef FUNC_VARS
+#undef LOCAL_VARS
+
+#undef SEGMENT_SIMPLE
+#undef SEGMENT_LOOP
+#undef SEGMENT_FAN