1 files changed, 64 insertions, 0 deletions
diff --git a/src/gallium/drivers/nouveau/nouveau_util.h b/src/gallium/drivers/nouveau/nouveau_util.h
new file mode 100644
index 00000000000..c92041ebeba
--- /dev/null
+++ b/src/gallium/drivers/nouveau/nouveau_util.h
@@ -0,0 +1,64 @@
+#ifndef __NOUVEAU_UTIL_H__
+#define __NOUVEAU_UTIL_H__
+
+/* Determine how many vertices can be pushed into the command stream.
+ * Where the remaining space isn't large enough to represent all verices,
+ * split the buffer at primitive boundaries.
+ *
+ * Returns a count of vertices that can be rendered, and an index to
+ * restart drawing at after a flush.
+ */
+static INLINE unsigned
+nouveau_vbuf_split(unsigned remaining, unsigned overhead, unsigned vpp,
+		   unsigned mode, unsigned start, unsigned count,
+		   unsigned *restart)
+{
+	int max, adj = 0;
+
+	max  = remaining - overhead;
+	if (max < 0)
+		return 0;
+
+	max *= vpp;
+	if (max >= count)
+		return count;
+
+	switch (mode) {
+	case PIPE_PRIM_POINTS:
+		break;
+	case PIPE_PRIM_LINES:
+		max = max & 1;
+		break;
+	case PIPE_PRIM_TRIANGLES:
+		max = max - (max % 3);
+		break;
+	case PIPE_PRIM_QUADS:
+		max = max & 3;
+		break;
+	case PIPE_PRIM_LINE_LOOP:
+	case PIPE_PRIM_LINE_STRIP:
+		if (max < 2)
+			max = 0;
+		adj = 1;
+		break;
+	case PIPE_PRIM_POLYGON:
+	case PIPE_PRIM_TRIANGLE_STRIP:
+	case PIPE_PRIM_TRIANGLE_FAN:
+		if (max < 3)
+			max = 0;
+		adj = 2;
+		break;
+	case PIPE_PRIM_QUAD_STRIP:
+		if (max < 4)
+			max = 0;
+		adj = 3;
+		break;
+	default:
+		assert(0);
+	}
+
+	*restart = start + max - adj;
+	return max;
+}
+
+#endif