UI: Grease Pencil Modifier Drag and Drop, Layout Changes

This patch implements the list panel system D7490 for grease pencil
modifiers. It also moves their drawing to a callback in
GpencilModifierTypeInfo in line with the extensible architecture
refactoring goal T75724.

This also adds the "set_error" function for grease pencil modifiers,
which hadn't been copied from mesh modifiers yet.

The implementation is basically exactly the same as for the modifier
patch (9b099c86123fc82).

Thanks to Matias Mendiola (mendio) for providing mockups for many
of the layout changes.

Differential Revision: https://developer.blender.org/D7978

1 files changed, 87 insertions, 0 deletions

diff --git a/source/blender/gpencil_modifiers/intern/MOD_gpencilhook.c b/source/blender/gpencil_modifiers/intern/MOD_gpencilhook.c
index d39c94e06d5..a0987aafcd2 100644
--- a/source/blender/gpencil_modifiers/intern/MOD_gpencilhook.c
+++ b/source/blender/gpencil_modifiers/intern/MOD_gpencilhook.c
@@ -28,15 +28,19 @@
 
 #include "BLI_math.h"
 
+#include "BLT_translation.h"
+
 #include "DNA_gpencil_modifier_types.h"
 #include "DNA_gpencil_types.h"
 #include "DNA_meshdata_types.h"
 #include "DNA_modifier_types.h"
 #include "DNA_object_types.h"
 #include "DNA_scene_types.h"
+#include "DNA_screen_types.h"
 
 #include "BKE_action.h"
 #include "BKE_colortools.h"
+#include "BKE_context.h"
 #include "BKE_deform.h"
 #include "BKE_gpencil_geom.h"
 #include "BKE_gpencil_modifier.h"
@@ -45,10 +49,17 @@
 #include "BKE_main.h"
 #include "BKE_modifier.h"
 #include "BKE_scene.h"
+#include "BKE_screen.h"
 
 #include "MEM_guardedalloc.h"
 
+#include "UI_interface.h"
+#include "UI_resources.h"
+
+#include "RNA_access.h"
+
 #include "MOD_gpencil_modifiertypes.h"
+#include "MOD_gpencil_ui_common.h"
 #include "MOD_gpencil_util.h"
 
 #include "DEG_depsgraph.h"
@@ -345,6 +356,81 @@ static void foreachIDLink(GpencilModifierData *md, Object *ob, IDWalkFunc walk,
   foreachObjectLink(md, ob, (ObjectWalkFunc)walk, userData);
 }
 
+static void panel_draw(const bContext *C, Panel *panel)
+{
+  uiLayout *sub, *row, *col;
+  uiLayout *layout = panel->layout;
+
+  PointerRNA ptr;
+  PointerRNA ob_ptr;
+  gpencil_modifier_panel_get_property_pointers(C, panel, &ob_ptr, &ptr);
+
+  PointerRNA hook_object_ptr = RNA_pointer_get(&ptr, "object");
+  bool has_vertex_group = RNA_string_length(&ptr, "vertex_group") != 0;
+
+  uiLayoutSetPropSep(layout, true);
+
+  col = uiLayoutColumn(layout, false);
+  uiItemR(col, &ptr, "object", 0, NULL, ICON_NONE);
+  if (!RNA_pointer_is_null(&hook_object_ptr) &&
+      RNA_enum_get(&hook_object_ptr, "type") == OB_ARMATURE) {
+    PointerRNA hook_object_data_ptr = RNA_pointer_get(&hook_object_ptr, "data");
+    uiItemPointerR(
+        col, &ptr, "subtarget", &hook_object_data_ptr, "bones", IFACE_("Bone"), ICON_NONE);
+  }
+
+  row = uiLayoutRow(layout, true);
+  uiItemPointerR(row, &ptr, "vertex_group", &ob_ptr, "vertex_groups", NULL, ICON_NONE);
+  sub = uiLayoutRow(row, true);
+  uiLayoutSetActive(sub, has_vertex_group);
+  uiLayoutSetPropSep(sub, false);
+  uiItemR(sub, &ptr, "invert_vertex", 0, "", ICON_ARROW_LEFTRIGHT);
+
+  uiItemR(layout, &ptr, "strength", UI_ITEM_R_SLIDER, NULL, ICON_NONE);
+
+  gpencil_modifier_panel_end(layout, &ptr);
+}
+
+static void falloff_panel_draw(const bContext *C, Panel *panel)
+{
+  uiLayout *row;
+  uiLayout *layout = panel->layout;
+
+  PointerRNA ptr;
+  gpencil_modifier_panel_get_property_pointers(C, panel, NULL, &ptr);
+
+  bool use_falloff = RNA_enum_get(&ptr, "falloff_type") != eWarp_Falloff_None;
+
+  uiLayoutSetPropSep(layout, true);
+
+  uiItemR(layout, &ptr, "falloff_type", 0, IFACE_("Type"), ICON_NONE);
+
+  row = uiLayoutRow(layout, false);
+  uiLayoutSetActive(row, use_falloff);
+  uiItemR(row, &ptr, "falloff_radius", 0, NULL, ICON_NONE);
+
+  uiItemR(layout, &ptr, "use_falloff_uniform", 0, NULL, ICON_NONE);
+
+  if (RNA_enum_get(&ptr, "falloff_type") == eWarp_Falloff_Curve) {
+    uiTemplateCurveMapping(layout, &ptr, "falloff_curve", 0, false, false, false, false);
+  }
+}
+
+static void mask_panel_draw(const bContext *C, Panel *panel)
+{
+  gpencil_modifier_masking_panel_draw(C, panel, true, false);
+}
+
+static void panelRegister(ARegionType *region_type)
+{
+  PanelType *panel_type = gpencil_modifier_panel_register(
+      region_type, eGpencilModifierType_Hook, panel_draw);
+  gpencil_modifier_subpanel_register(
+      region_type, "falloff", "Falloff", NULL, falloff_panel_draw, panel_type);
+  gpencil_modifier_subpanel_register(
+      region_type, "mask", "Influence", NULL, mask_panel_draw, panel_type);
+}
+
 GpencilModifierTypeInfo modifierType_Gpencil_Hook = {
     /* name */ "Hook",
     /* structName */ "HookGpencilModifierData",
@@ -367,4 +453,5 @@ GpencilModifierTypeInfo modifierType_Gpencil_Hook = {
     /* foreachObjectLink */ foreachObjectLink,
     /* foreachIDLink */ foreachIDLink,
     /* foreachTexLink */ NULL,
+    /* panelRegister */ panelRegister,
 };