Grease Pencil: Add LineArt modifier

This adds the LineArt grease pencil modifier.

It takes objects or collections as input and generates various grease
pencil lines from these objects with the help of the active scene
camera. For example it can generate contour lines, intersection lines
and crease lines to name a few.

This is really useful as artists can then use 3D meshes to automatically
generate grease pencil lines for characters, enviroments or other
visualization purposes.

These lines can then be baked and edited as regular grease pencil lines.

Reviewed By: Sebastian Parborg, Antonio Vazquez, Matias Mendiola

Differential Revision: http://developer.blender.org/D8758

1 files changed, 11 insertions, 0 deletions

diff --git a/source/blender/makesdna/DNA_material_types.h b/source/blender/makesdna/DNA_material_types.h
index 884c2df6480..55d5ea202f7 100644
--- a/source/blender/makesdna/DNA_material_types.h
+++ b/source/blender/makesdna/DNA_material_types.h
@@ -145,6 +145,16 @@ typedef enum eMaterialGPencilStyle_Mode {
   GP_MATERIAL_MODE_SQUARE = 2,
 } eMaterialGPencilStyle_Mode;
 
+typedef struct MaterialLineArt {
+  int flags; /* eMaterialLineArtFlags */
+  unsigned char transparency_mask;
+  unsigned char _pad[3];
+} MaterialLineArt;
+
+typedef enum eMaterialLineArtFlags {
+  LRT_MATERIAL_TRANSPARENCY_ENABLED = (1 << 0),
+} eMaterialLineArtFlags;
+
 typedef struct Material {
   ID id;
   /** Animation data (must be immediately after id for utilities to use it). */
@@ -210,6 +220,7 @@ typedef struct Material {
 
   /** Grease pencil color. */
   struct MaterialGPencilStyle *gp_style;
+  struct MaterialLineArt lineart;
 } Material;
 
 /* **************** MATERIAL ********************* */