X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;ds=sidebyside;f=src%2Fgallium%2Fauxiliary%2Findices%2Fu_unfilled_indices.c;h=c353717d65644b7ff5f94b266cd32124e8b6e7d8;hb=70daad6a99c9815fd55ffa016d35684e4414f257;hp=26c5d4d4c72cad1fc664658973dab87a7f2a4563;hpb=f0c92d96568780d5a6c6b53845e9689893ce99e4;p=mesa.git

diff --git a/src/gallium/auxiliary/indices/u_unfilled_indices.c b/src/gallium/auxiliary/indices/u_unfilled_indices.c
index 26c5d4d4c72..c353717d656 100644
--- a/src/gallium/auxiliary/indices/u_unfilled_indices.c
+++ b/src/gallium/auxiliary/indices/u_unfilled_indices.c
@@ -71,6 +71,11 @@ static void generate_linear_uint( unsigned nr,
 }
 
 
+/**
+ * Given a primitive type and number of vertices, return the number of vertices
+ * needed to draw the primitive with fill mode = PIPE_POLYGON_MODE_LINE using
+ * separate lines (PIPE_PRIM_LINES).
+ */
 static unsigned nr_lines( unsigned prim,
                           unsigned nr )
 {
@@ -86,7 +91,7 @@ static unsigned nr_lines( unsigned prim,
    case PIPE_PRIM_QUAD_STRIP:
       return (nr - 2) / 2 * 8;
    case PIPE_PRIM_POLYGON:
-      return (nr - 2) * 6;
+      return 2 * nr; /* a line (two verts) for each polygon edge */
    default:
       assert(0);
       return 0;