LineArt: Shadow and related functionalities.

This patch includes the full shadow functionality for LineArt:

- Light contour and cast shadow lines.
- Lit/shaded region selection.
- Enclosed light/shadow shape calculation.
- Silhouette/anti-silhouette selection.
- Intersection priority based on shadow edge identifier.

Reviewed By: Sebastian Parborg (zeddb)

Differential Revision: https://developer.blender.org/D15109

4 files changed, 137 insertions, 3 deletions

diff --git a/source/blender/makesrna/intern/rna_collection.c b/source/blender/makesrna/intern/rna_collection.c
index 599d36c0af7..8cd83ddcf12 100644
--- a/source/blender/makesrna/intern/rna_collection.c
+++ b/source/blender/makesrna/intern/rna_collection.c
@@ -549,6 +549,22 @@ void RNA_def_collections(BlenderRNA *brna)
       prop, "Masks", "Intersection generated by this collection will have this mask value");
   RNA_def_property_update(prop, NC_SCENE, NULL);
 
+  prop = RNA_def_property(srna, "lineart_intersection_priority", PROP_INT, PROP_NONE);
+  RNA_def_property_range(prop, 0, 255);
+  RNA_def_property_ui_text(prop,
+                           "Intersection Priority",
+                           "The intersection line will be included into the object with the "
+                           "higher intersection priority value");
+  RNA_def_property_update(prop, NC_SCENE, NULL);
+
+  prop = RNA_def_property(srna, "use_lineart_intersection_priority", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_default(prop, 0);
+  RNA_def_property_boolean_sdna(
+      prop, NULL, "lineart_flags", COLLECTION_LRT_USE_INTERSECTION_PRIORITY);
+  RNA_def_property_ui_text(
+      prop, "Use Intersection Priority", "Assign intersection priority value for this collection");
+  RNA_def_property_update(prop, NC_SCENE, NULL);
+
   prop = RNA_def_property(srna, "color_tag", PROP_ENUM, PROP_NONE);
   RNA_def_property_enum_sdna(prop, NULL, "color_tag");
   RNA_def_property_enum_funcs(
diff --git a/source/blender/makesrna/intern/rna_gpencil_modifier.c b/source/blender/makesrna/intern/rna_gpencil_modifier.c
index 47bed955b54..89bfb5684e2 100644
--- a/source/blender/makesrna/intern/rna_gpencil_modifier.c
+++ b/source/blender/makesrna/intern/rna_gpencil_modifier.c
@@ -3196,6 +3196,20 @@ static void rna_def_modifier_gpencillineart(BlenderRNA *brna)
       {0, NULL, 0, NULL, NULL},
   };
 
+  static const EnumPropertyItem modifier_lineart_shadow_region_filtering[] = {
+      {LRT_SHADOW_FILTER_NONE, "NONE", 0, "None", ""},
+      {LRT_SHADOW_FILTER_LIT, "LIT", 0, "Lit", ""},
+      {LRT_SHADOW_FILTER_SHADED, "SHADED", 0, "Shaded", ""},
+      {0, NULL, 0, NULL, NULL},
+  };
+
+  static const EnumPropertyItem modifier_lineart_silhouette_filtering[] = {
+      {LRT_SILHOUETTE_FILTER_NONE, "NONE", 0, "Contour", ""},
+      {LRT_SILHOUETTE_FILTER_GROUP, "GROUP", 0, "Silhouette", ""},
+      {LRT_SILHOUETTE_FILTER_INDIVIDUAL, "INDIVIDUAL", 0, "Individual Silhouette", ""},
+      {0, NULL, 0, NULL, NULL},
+  };
+
   srna = RNA_def_struct(brna, "LineartGpencilModifier", "GpencilModifier");
   RNA_def_struct_ui_text(
       srna, "Line Art Modifier", "Generate line art strokes from selected source");
@@ -3208,7 +3222,7 @@ static void rna_def_modifier_gpencillineart(BlenderRNA *brna)
   RNA_def_property_boolean_sdna(prop, NULL, "calculation_flags", LRT_USE_CUSTOM_CAMERA);
   RNA_def_property_ui_text(
       prop, "Use Custom Camera", "Use custom camera instead of the active camera");
-  RNA_def_property_update(prop, NC_SCENE, "rna_GpencilModifier_update");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_dependency_update");
 
   prop = RNA_def_property(srna, "use_fuzzy_intersections", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "calculation_flags", LRT_INTERSECTION_AS_CONTOUR);
@@ -3250,8 +3264,11 @@ static void rna_def_modifier_gpencillineart(BlenderRNA *brna)
   prop = RNA_def_property(srna, "crease_threshold", PROP_FLOAT, PROP_ANGLE);
   RNA_def_property_range(prop, 0, DEG2RAD(180.0f));
   RNA_def_property_ui_range(prop, 0.0f, DEG2RAD(180.0f), 0.01f, 1);
-  RNA_def_property_ui_text(
-      prop, "Crease Threshold", "Angles smaller than this will be treated as creases");
+  RNA_def_property_ui_text(prop,
+                           "Crease Threshold",
+                           "Angles smaller than this will be treated as creases. Crease angle "
+                           "priority: object line art crease override > mesh auto smooth angle > "
+                           "line art default crease.");
   RNA_def_property_update(prop, NC_SCENE, "rna_GpencilModifier_update");
 
   prop = RNA_def_property(srna, "split_angle", PROP_FLOAT, PROP_ANGLE);
@@ -3367,6 +3384,14 @@ static void rna_def_modifier_gpencillineart(BlenderRNA *brna)
       prop, "Camera Object", "Use specified camera object for generating line art");
   RNA_def_property_update(prop, 0, "rna_GpencilModifier_dependency_update");
 
+  prop = RNA_def_property(srna, "light_contour_object", PROP_POINTER, PROP_NONE);
+  RNA_def_property_flag(prop, PROP_EDITABLE | PROP_ID_SELF_CHECK);
+  RNA_def_property_struct_type(prop, "Object");
+  RNA_def_property_override_flag(prop, PROPOVERRIDE_OVERRIDABLE_LIBRARY);
+  RNA_def_property_ui_text(
+      prop, "Light Object", "Use this light object to generate light contour");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_dependency_update");
+
   prop = RNA_def_property(srna, "source_type", PROP_ENUM, PROP_NONE);
   RNA_def_property_enum_items(prop, modifier_lineart_source_type);
   RNA_def_property_ui_text(prop, "Source Type", "Line art stroke source type");
@@ -3417,6 +3442,41 @@ static void rna_def_modifier_gpencillineart(BlenderRNA *brna)
   RNA_def_property_ui_text(prop, "Use Intersection", "Generate strokes from intersections");
   RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
 
+  prop = RNA_def_property(srna, "use_light_contour", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "edge_types", LRT_EDGE_FLAG_LIGHT_CONTOUR);
+  RNA_def_property_ui_text(prop,
+                           "Use Light Contour",
+                           "Generate light/shadow separation lines from a reference light object");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "use_shadow", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "edge_types", LRT_EDGE_FLAG_PROJECTED_SHADOW);
+  RNA_def_property_ui_text(
+      prop, "Use Shadow", "Project contour lines using a light shource object");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "shadow_region_filtering", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_sdna(prop, NULL, "shadow_selection");
+  RNA_def_property_enum_items(prop, modifier_lineart_shadow_region_filtering);
+  RNA_def_property_ui_text(prop,
+                           "Shadow Region Filtering",
+                           "Select feature lines that comes from lit or shaded regions. Will not "
+                           "affect cast shadow and light contour since they are at the border");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_dependency_update");
+
+  prop = RNA_def_property(srna, "shadow_enclosed_shapes", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "calculation_flags", LRT_SHADOW_ENCLOSED_SHAPES);
+  RNA_def_property_ui_text(prop,
+                           "Shadow Enclosed Shapes",
+                           "Reproject visible lines again to get enclosed shadow shapes");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "silhouette_filtering", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_sdna(prop, NULL, "silhouette_selection");
+  RNA_def_property_enum_items(prop, modifier_lineart_silhouette_filtering);
+  RNA_def_property_ui_text(prop, "Silhouette Filtering", "Select contour or silhouette");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_dependency_update");
+
   prop = RNA_def_property(srna, "use_multiple_levels", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "use_multiple_levels", 0);
   RNA_def_property_ui_text(
@@ -3558,6 +3618,27 @@ static void rna_def_modifier_gpencillineart(BlenderRNA *brna)
       "different occlusion levels than when disabled");
   RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
 
+  prop = RNA_def_property(srna, "shadow_camera_near", PROP_FLOAT, PROP_NONE);
+  RNA_def_property_ui_text(prop, "Shadow Camera Near", "Near clipping distance of shadow camera");
+  RNA_def_property_ui_range(prop, 0.0f, 500.0f, 0.1f, 2);
+  RNA_def_property_range(prop, 0.0f, 10000.0f);
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "shadow_camera_far", PROP_FLOAT, PROP_NONE);
+  RNA_def_property_ui_text(prop, "Shadow Camera Far", "Far clipping distance of shadow camera");
+  RNA_def_property_ui_range(prop, 0.0f, 500.0f, 0.1f, 2);
+  RNA_def_property_range(prop, 0.0f, 10000.0f);
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "shadow_camera_size", PROP_FLOAT, PROP_NONE);
+  RNA_def_property_ui_text(prop,
+                           "Shadow Camera Size",
+                           "This value represent the \"Orthographic Scale\" of an ortho camera."
+                           "If the camera is put at the lamps position with this scale, it will "
+                           "represent the coverage of the shadow \"camera\" ");
+  RNA_def_property_ui_range(prop, 0.0f, 500.0f, 0.1f, 2);
+  RNA_def_property_range(prop, 0.0f, 10000.0f);
+
   prop = RNA_def_property(srna, "use_invert_collection", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flags", LRT_GPENCIL_INVERT_COLLECTION);
   RNA_def_property_ui_text(prop,
@@ -3565,6 +3646,11 @@ static void rna_def_modifier_gpencillineart(BlenderRNA *brna)
                            "Select everything except lines from specified collection");
   RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
 
+  prop = RNA_def_property(srna, "use_invert_silhouette", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "flags", LRT_GPENCIL_INVERT_SILHOUETTE_FILTER);
+  RNA_def_property_ui_text(prop, "Invert Silhouette Filtering", "Select anti-silhouette lines");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
   RNA_define_lib_overridable(false);
 }
 
diff --git a/source/blender/makesrna/intern/rna_material.c b/source/blender/makesrna/intern/rna_material.c
index 4fb7495bac8..4a9bc608598 100644
--- a/source/blender/makesrna/intern/rna_material.c
+++ b/source/blender/makesrna/intern/rna_material.c
@@ -754,6 +754,22 @@ static void rna_def_material_lineart(BlenderRNA *brna)
       "Effectiveness",
       "Faces with this material will behave as if it has set number of layers in occlusion");
   RNA_def_property_update(prop, NC_GPENCIL | ND_SHADING, "rna_MaterialLineArt_update");
+
+  prop = RNA_def_property(srna, "intersection_priority", PROP_INT, PROP_NONE);
+  RNA_def_property_range(prop, 0, 255);
+  RNA_def_property_ui_text(prop,
+                           "Intersection Priority",
+                           "The intersection line will be included into the object with the "
+                           "higher intersection priority value");
+  RNA_def_property_update(prop, NC_GPENCIL | ND_SHADING, "rna_MaterialLineArt_update");
+
+  prop = RNA_def_property(srna, "use_intersection_priority_override", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_default(prop, 0);
+  RNA_def_property_boolean_sdna(prop, NULL, "flags", LRT_MATERIAL_CUSTOM_INTERSECTION_PRIORITY);
+  RNA_def_property_ui_text(prop,
+                           "Use Intersection Priority",
+                           "Override object and collection intersection priority value");
+  RNA_def_property_update(prop, NC_GPENCIL | ND_SHADING, "rna_MaterialLineArt_update");
 }
 
 void RNA_def_material(BlenderRNA *brna)
diff --git a/source/blender/makesrna/intern/rna_object.c b/source/blender/makesrna/intern/rna_object.c
index 46e8b3beb02..99315a580cf 100644
--- a/source/blender/makesrna/intern/rna_object.c
+++ b/source/blender/makesrna/intern/rna_object.c
@@ -2950,6 +2950,22 @@ static void rna_def_object_lineart(BlenderRNA *brna)
   RNA_def_property_ui_range(prop, 0.0f, DEG2RAD(180.0f), 0.01f, 1);
   RNA_def_property_ui_text(prop, "Crease", "Angles smaller than this will be treated as creases");
   RNA_def_property_update(prop, 0, "rna_object_lineart_update");
+
+  prop = RNA_def_property(srna, "use_intersection_priority_override", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "flags", OBJECT_LRT_OWN_INTERSECTION_PRIORITY);
+  RNA_def_property_ui_text(
+      prop,
+      "Use Intersection Priority",
+      "Use this object's intersection priority to override collection setting");
+  RNA_def_property_update(prop, 0, "rna_object_lineart_update");
+
+  prop = RNA_def_property(srna, "intersection_priority", PROP_INT, PROP_NONE);
+  RNA_def_property_range(prop, 0, 255);
+  RNA_def_property_ui_text(prop,
+                           "Intersection Priority",
+                           "The intersection line will be included into the object with the "
+                           "higher intersection priority value");
+  RNA_def_property_update(prop, NC_GPENCIL | ND_SHADING, "rna_object_lineart_update");
 }
 
 static void rna_def_object_visibility(StructRNA *srna)