Freestyle: New options for sorting to arrange the stacking order of lines.

Line styles now have a set of new options for rearranging the stacking order of lines.
This gives artists more control to determine which lines should be drawn on top of others.
Two available sort keys are the distance from camera and curvilinear 2D length.
Since the distance of a line from camera may vary over vertices, another option called
integration type is used to compute the sort key for a line from the values computed at
individual vertices.  Available integration types are MEAN, MIN, MAX, FIRST and LAST
(see the tool tips for more detail).

1 files changed, 41 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_linestyle.c b/source/blender/makesrna/intern/rna_linestyle.c
index 0619bb0352a..e97f3c2b418 100644
--- a/source/blender/makesrna/intern/rna_linestyle.c
+++ b/source/blender/makesrna/intern/rna_linestyle.c
@@ -915,6 +915,24 @@ static void rna_def_linestyle(BlenderRNA *brna)
 		{LS_THICKNESS_RELATIVE, "RELATIVE", 0, "Relative", "Stroke thickness is split by a user-defined ratio"},
 		{0, NULL, 0, NULL, NULL}
 	};
+	static EnumPropertyItem sort_key_items[] = {
+		{LS_SORT_KEY_DISTANCE_FROM_CAMERA, "DISTANCE_FROM_CAMERA", 0, "Distance from Camera", "Sort by distance from camera (closer lines lie on top of further lines)"},
+		{LS_SORT_KEY_2D_LENGTH, "2D_LENGTH", 0, "2D Length", "Sort by curvilinear 2D length (longer lines lie on top of shorter lines)"},
+		{0, NULL, 0, NULL, NULL}
+	};
+	static EnumPropertyItem sort_order_items[] = {
+		{0, "DEFAULT", 0, "Default", "Default order of the sort key"},
+		{LS_REVERSE_ORDER, "REVERSE", 0, "Reverse", "Reverse order"},
+		{0, NULL, 0, NULL, NULL}
+	};
+	static EnumPropertyItem integration_type_items[] = {
+		{LS_INTEGRATION_MEAN, "MEAN", 0, "Mean", "The value computed for the chain is the mean of the values obtained for chain vertices"},
+		{LS_INTEGRATION_MIN, "MIN", 0, "Min", "The value computed for the chain is the minimum of the values obtained for chain vertices"},
+		{LS_INTEGRATION_MAX, "MAX", 0, "Max", "The value computed for the chain is the maximum of the values obtained for chain vertices"},
+		{LS_INTEGRATION_FIRST, "FIRST", 0, "First", "The value computed for the chain is the value obtained for the first chain vertex"},
+		{LS_INTEGRATION_LAST, "LAST", 0, "Last", "The value computed for the chain is the value obtained for the last chain vertex"},
+		{0, NULL, 0, NULL, NULL}
+	};
 
 	srna = RNA_def_struct(brna, "FreestyleLineStyle", "ID");
 	RNA_def_struct_ui_text(srna, "Freestyle Line Style", "Freestyle line style, reusable by multiple line sets");
@@ -1104,6 +1122,29 @@ static void rna_def_linestyle(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Material Boundary", "If true, chains of feature edges are split at material boundaries");
 	RNA_def_property_update(prop, NC_LINESTYLE, NULL);
 
+	prop = RNA_def_property(srna, "use_sorting", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_negative_sdna(prop, NULL, "flag", LS_NO_SORTING);
+	RNA_def_property_ui_text(prop, "Sorting", "Arrange the stacking order of strokes");
+	RNA_def_property_update(prop, NC_LINESTYLE, NULL);
+
+	prop = RNA_def_property(srna, "sort_key", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_sdna(prop, NULL, "sort_key");
+	RNA_def_property_enum_items(prop, sort_key_items);
+	RNA_def_property_ui_text(prop, "Sort Key", "Select the sort key to determine the stacking order of chains");
+	RNA_def_property_update(prop, NC_LINESTYLE, NULL);
+
+	prop = RNA_def_property(srna, "sort_order", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_bitflag_sdna(prop, NULL, "flag");
+	RNA_def_property_enum_items(prop, sort_order_items);
+	RNA_def_property_ui_text(prop, "Sort Order", "Select the sort order");
+	RNA_def_property_update(prop, NC_LINESTYLE, NULL);
+
+	prop = RNA_def_property(srna, "integration_type", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_sdna(prop, NULL, "integration_type");
+	RNA_def_property_enum_items(prop, integration_type_items);
+	RNA_def_property_ui_text(prop, "Integration Type", "Select the way how the sort key is computed for each chain");
+	RNA_def_property_update(prop, NC_LINESTYLE, NULL);
+
 	prop = RNA_def_property(srna, "use_dashed_line", PROP_BOOLEAN, PROP_NONE);
 	RNA_def_property_boolean_sdna(prop, NULL, "flag", LS_DASHED_LINE);
 	RNA_def_property_ui_text(prop, "Dashed Line", "Enable or disable dashed line");