1 files changed, 25 insertions, 5 deletions

diff --git a/source/blender/blenlib/BLI_bitmap_draw_2d.h b/source/blender/blenlib/BLI_bitmap_draw_2d.h
index 8331d8fac08..3831ed3c9e7 100644
--- a/source/blender/blenlib/BLI_bitmap_draw_2d.h
+++ b/source/blender/blenlib/BLI_bitmap_draw_2d.h
@@ -24,23 +24,43 @@
 extern "C" {
 #endif
 
+/**
+ * Plot a line from \a p1 to \a p2 (inclusive).
+ *
+ * \note For clipped line drawing, see: http://stackoverflow.com/a/40902741/432509
+ */
 void BLI_bitmap_draw_2d_line_v2v2i(const int p1[2],
                                    const int p2[2],
                                    bool (*callback)(int, int, void *),
                                    void *user_data);
 
+/**
+ * \note Unclipped (clipped version can be added if needed).
+ */
 void BLI_bitmap_draw_2d_tri_v2i(const int p1[2],
                                 const int p2[2],
                                 const int p3[2],
                                 void (*callback)(int x, int x_end, int y, void *),
                                 void *user_data);
 
-void BLI_bitmap_draw_2d_poly_v2i_n(const int xmin,
-                                   const int ymin,
-                                   const int xmax,
-                                   const int ymax,
+/**
+ * Draws a filled polygon with support for self intersections.
+ *
+ * \param callback: Takes the x, y coords and x-span (\a x_end is not inclusive),
+ * note that \a x_end will always be greater than \a x, so we can use:
+ *
+ * \code{.c}
+ * do {
+ *     func(x, y);
+ * } while (++x != x_end);
+ * \endcode
+ */
+void BLI_bitmap_draw_2d_poly_v2i_n(int xmin,
+                                   int ymin,
+                                   int xmax,
+                                   int ymax,
                                    const int verts[][2],
-                                   const int verts_len,
+                                   int verts_len,
                                    void (*callback)(int x, int x_end, int y, void *),
                                    void *user_data);