GPencil: Fading for build modifier.

Adds fading support for build modifier so it's not a hard cut off

Reviewed By: Antonio Vazquez (antoniov), Matias Mendiola (mendio)

Differential Revision: https://developer.blender.org/D14309

1 files changed, 43 insertions, 3 deletions

diff --git a/source/blender/makesrna/intern/rna_gpencil_modifier.c b/source/blender/makesrna/intern/rna_gpencil_modifier.c
index 81103f4fe49..f6e44ae7cd8 100644
--- a/source/blender/makesrna/intern/rna_gpencil_modifier.c
+++ b/source/blender/makesrna/intern/rna_gpencil_modifier.c
@@ -382,6 +382,7 @@ RNA_GP_MOD_VGROUP_NAME_SET(WeightAngle, vgname);
 RNA_GP_MOD_VGROUP_NAME_SET(Lineart, vgname);
 RNA_GP_MOD_VGROUP_NAME_SET(Shrinkwrap, vgname);
 RNA_GP_MOD_VGROUP_NAME_SET(Envelope, vgname);
+RNA_GP_MOD_VGROUP_NAME_SET(Build, target_vgname);
 
 #  undef RNA_GP_MOD_VGROUP_NAME_SET
 
@@ -416,6 +417,7 @@ RNA_GP_MOD_OBJECT_SET(Mirror, object, OB_EMPTY);
 RNA_GP_MOD_OBJECT_SET(WeightProx, object, OB_EMPTY);
 RNA_GP_MOD_OBJECT_SET(Shrinkwrap, target, OB_MESH);
 RNA_GP_MOD_OBJECT_SET(Shrinkwrap, aux_target, OB_MESH);
+RNA_GP_MOD_OBJECT_SET(Build, object, OB_EMPTY);
 
 #  undef RNA_GP_MOD_OBJECT_SET
 
@@ -2133,10 +2135,10 @@ static void rna_def_modifier_gpencilbuild(BlenderRNA *brna)
        "Shrink",
        "Hide points from the end of each stroke to the start "
        "(e.g. for animating lines being erased)"},
-      {GP_BUILD_TRANSITION_FADE,
-       "FADE",
+      {GP_BUILD_TRANSITION_VANISH,
+       "FADE", /* "Fade" is the original id string kept for compatibility purpose. */
        0,
-       "Fade",
+       "Vanish",
        "Hide points in the order they occur in each stroke "
        "(e.g. for animating ink fading or vanishing after getting drawn)"},
       {0, NULL, 0, NULL, NULL},
@@ -2242,6 +2244,44 @@ static void rna_def_modifier_gpencilbuild(BlenderRNA *brna)
   RNA_def_property_range(prop, MINAFRAMEF, MAXFRAMEF);
   RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
 
+  prop = RNA_def_property(srna, "use_fading", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_property_boolean_sdna(prop, NULL, "flag", GP_BUILD_USE_FADING);
+  RNA_def_property_ui_text(
+      prop, "Use Fading", "Fade out strokes instead of directly cutting off.");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "fade_factor", PROP_FLOAT, PROP_FACTOR);
+  RNA_def_property_float_sdna(prop, NULL, "fade_fac");
+  RNA_def_property_ui_text(prop, "Fade Factor", "Defines how much of the stroke is fading in/out");
+  RNA_def_property_range(prop, 0.0f, 1.0f);
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "target_vertex_group", PROP_STRING, PROP_NONE);
+  RNA_def_property_string_sdna(prop, NULL, "target_vgname");
+  RNA_def_property_ui_text(prop, "Vertex Group", "Output Vertex group");
+  RNA_def_property_string_funcs(prop, NULL, NULL, "rna_BuildGpencilModifier_target_vgname_set");
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "fade_opacity_strength", PROP_FLOAT, PROP_FACTOR);
+  RNA_def_property_float_sdna(prop, NULL, "fade_opacity_strength");
+  RNA_def_property_ui_text(
+      prop, "Opacity Strength", "How much strength fading applies on top of stroke opacity");
+  RNA_def_property_range(prop, 0.0f, 1.0f);
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "fade_thickness_strength", PROP_FLOAT, PROP_FACTOR);
+  RNA_def_property_float_sdna(prop, NULL, "fade_thickness_strength");
+  RNA_def_property_ui_text(
+      prop, "Thickness Strength", "How much strength fading applies on top of stroke thickness");
+  RNA_def_property_range(prop, 0.0f, 1.0f);
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_update");
+
+  prop = RNA_def_property(srna, "object", PROP_POINTER, PROP_NONE);
+  RNA_def_property_ui_text(prop, "Object", "Object used as build starting position");
+  RNA_def_property_pointer_funcs(prop, NULL, "rna_BuildGpencilModifier_object_set", NULL, NULL);
+  RNA_def_property_flag(prop, PROP_EDITABLE | PROP_ID_SELF_CHECK);
+  RNA_def_property_update(prop, 0, "rna_GpencilModifier_dependency_update");
+
   /* Filters - Layer */
   prop = RNA_def_property(srna, "layer", PROP_STRING, PROP_NONE);
   RNA_def_property_string_sdna(prop, NULL, "layername");