Displace modifier: add global/local space option for X/Y/Z/XYZ directions.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D2309

4 files changed, 72 insertions, 10 deletions

diff --git a/release/scripts/startup/bl_ui/properties_data_modifier.py b/release/scripts/startup/bl_ui/properties_data_modifier.py
index 84ee06c7d70..540c29f31e4 100644
--- a/release/scripts/startup/bl_ui/properties_data_modifier.py
+++ b/release/scripts/startup/bl_ui/properties_data_modifier.py
@@ -336,6 +336,9 @@ class DATA_PT_modifiers(ModifierButtonsPanel, Panel):
         col = split.column(align=True)
         col.label(text="Direction:")
         col.prop(md, "direction", text="")
+        if md.direction in {'X', 'Y', 'Z', 'RGB_TO_XYZ'}:
+            col.label(text="Space:")
+            col.prop(md, "space", text="")
         col.label(text="Vertex Group:")
         col.prop_search(md, "vertex_group", ob, "vertex_groups", text="")
 
diff --git a/source/blender/makesdna/DNA_modifier_types.h b/source/blender/makesdna/DNA_modifier_types.h
index 9187b76f012..1398e9de76f 100644
--- a/source/blender/makesdna/DNA_modifier_types.h
+++ b/source/blender/makesdna/DNA_modifier_types.h
@@ -383,7 +383,7 @@ typedef struct DisplaceModifierData {
 	int direction;
 	char defgrp_name[64];   /* MAX_VGROUP_NAME */
 	float midlevel;
-	int pad;
+	int space;
 } DisplaceModifierData;
 
 /* DisplaceModifierData->direction */
@@ -404,6 +404,12 @@ enum {
 	MOD_DISP_MAP_UV     = 3,
 };
 
+/* DisplaceModifierData->space */
+enum {
+	MOD_DISP_SPACE_LOCAL  = 0,
+	MOD_DISP_SPACE_GLOBAL = 1,
+};
+
 typedef struct UVProjectModifierData {
 	ModifierData modifier;
 
diff --git a/source/blender/makesrna/intern/rna_modifier.c b/source/blender/makesrna/intern/rna_modifier.c
index 34ca6a12fc3..39f6298ca61 100644
--- a/source/blender/makesrna/intern/rna_modifier.c
+++ b/source/blender/makesrna/intern/rna_modifier.c
@@ -2100,6 +2100,12 @@ static void rna_def_modifier_displace(BlenderRNA *brna)
 		{0, NULL, 0, NULL, NULL}
 	};
 
+	static EnumPropertyItem prop_space_items[] = {
+		{MOD_DISP_SPACE_LOCAL, "LOCAL", 0, "Local", "Direction is defined in local coordinates"},
+		{MOD_DISP_SPACE_GLOBAL, "GLOBAL", 0, "Global", "Direction is defined in global coordinates"},
+		{0, NULL, 0, NULL, NULL}
+	};
+
 	srna = RNA_def_struct(brna, "DisplaceModifier", "Modifier");
 	RNA_def_struct_ui_text(srna, "Displace Modifier", "Displacement modifier");
 	RNA_def_struct_sdna(srna, "DisplaceModifierData");
@@ -2130,6 +2136,11 @@ static void rna_def_modifier_displace(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Direction", "");
 	RNA_def_property_update(prop, 0, "rna_Modifier_update");
 
+	prop = RNA_def_property(srna, "space", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_items(prop, prop_space_items);
+	RNA_def_property_ui_text(prop, "Space", "");
+	RNA_def_property_update(prop, 0, "rna_Modifier_dependency_update");
+
 	rna_def_modifier_generic_map_info(srna);
 }
 
diff --git a/source/blender/modifiers/intern/MOD_displace.c b/source/blender/modifiers/intern/MOD_displace.c
index 9ba2d214d50..059e096ddb4 100644
--- a/source/blender/modifiers/intern/MOD_displace.c
+++ b/source/blender/modifiers/intern/MOD_displace.c
@@ -46,6 +46,7 @@
 #include "BKE_modifier.h"
 #include "BKE_texture.h"
 #include "BKE_deform.h"
+#include "BKE_object.h"
 
 #include "depsgraph_private.h"
 #include "MEM_guardedalloc.h"
@@ -65,6 +66,7 @@ static void initData(ModifierData *md)
 	dmd->strength = 1;
 	dmd->direction = MOD_DISP_DIR_NOR;
 	dmd->midlevel = 0.5;
+	dmd->space = MOD_DISP_SPACE_LOCAL;
 }
 
 static void copyData(ModifierData *md, ModifierData *target)
@@ -171,10 +173,13 @@ static void updateDepgraph(ModifierData *md, DagForest *forest,
 	}
 	
 
-	if (dmd->texmapping == MOD_DISP_MAP_GLOBAL)
+	if (dmd->texmapping == MOD_DISP_MAP_GLOBAL ||
+	    (ELEM(dmd->direction, MOD_DISP_DIR_X, MOD_DISP_DIR_Y, MOD_DISP_DIR_Z, MOD_DISP_DIR_RGB_XYZ) &&
+	    dmd->space == MOD_DISP_SPACE_GLOBAL))
+	{
 		dag_add_relation(forest, obNode, obNode,
 		                 DAG_RL_DATA_DATA | DAG_RL_OB_DATA, "Displace Modifier");
-	
+	}
 }
 
 static void updateDepsgraph(ModifierData *md,
@@ -187,7 +192,10 @@ static void updateDepsgraph(ModifierData *md,
 	if (dmd->map_object != NULL && dmd->texmapping == MOD_DISP_MAP_OBJECT) {
 		DEG_add_object_relation(node, dmd->map_object, DEG_OB_COMP_TRANSFORM, "Displace Modifier");
 	}
-	if (dmd->texmapping == MOD_DISP_MAP_GLOBAL) {
+	if (dmd->texmapping == MOD_DISP_MAP_GLOBAL ||
+	    (ELEM(dmd->direction, MOD_DISP_DIR_X, MOD_DISP_DIR_Y, MOD_DISP_DIR_Z, MOD_DISP_DIR_RGB_XYZ) &&
+	    dmd->space == MOD_DISP_SPACE_GLOBAL))
+	{
 		DEG_add_object_relation(node, ob, DEG_OB_COMP_TRANSFORM, "Displace Modifier");
 	}
 }
@@ -206,6 +214,8 @@ static void displaceModifier_do(
 	float weight = 1.0f; /* init value unused but some compilers may complain */
 	const float delta_fixed = 1.0f - dmd->midlevel;  /* when no texture is used, we fallback to white */
 	float (*vert_clnors)[3] = NULL;
+	float local_mat[4][4];
+	const bool use_global_direction = dmd->space == MOD_DISP_SPACE_GLOBAL;
 
 	if (!dmd->texture && dmd->direction == MOD_DISP_DIR_RGB_XYZ) return;
 	if (dmd->strength == 0.0f) return;
@@ -243,11 +253,17 @@ static void displaceModifier_do(
 			direction = MOD_DISP_DIR_NOR;
 		}
 	}
+	else if (ELEM(direction, MOD_DISP_DIR_X, MOD_DISP_DIR_Y, MOD_DISP_DIR_Z, MOD_DISP_DIR_RGB_XYZ) &&
+	         use_global_direction)
+	{
+		copy_m4_m4(local_mat, ob->obmat);
+	}
 
 	for (i = 0; i < numVerts; i++) {
 		TexResult texres;
 		float strength = dmd->strength;
 		float delta;
+		float local_vec[3];
 
 		if (dvert) {
 			weight = defvert_find_weight(dvert + i, defgrp_index);
@@ -270,18 +286,44 @@ static void displaceModifier_do(
 
 		switch (direction) {
 			case MOD_DISP_DIR_X:
-				vertexCos[i][0] += delta;
+				if (use_global_direction) {
+					vertexCos[i][0] += delta * local_mat[0][0];
+					vertexCos[i][1] += delta * local_mat[1][0];
+					vertexCos[i][2] += delta * local_mat[2][0];
+				}
+				else {
+					vertexCos[i][0] += delta;
+				}
 				break;
 			case MOD_DISP_DIR_Y:
-				vertexCos[i][1] += delta;
+				if (use_global_direction) {
+					vertexCos[i][0] += delta * local_mat[0][1];
+					vertexCos[i][1] += delta * local_mat[1][1];
+					vertexCos[i][2] += delta * local_mat[2][1];
+				}
+				else {
+					vertexCos[i][1] += delta;
+				}
 				break;
 			case MOD_DISP_DIR_Z:
-				vertexCos[i][2] += delta;
+				if (use_global_direction) {
+					vertexCos[i][0] += delta * local_mat[0][2];
+					vertexCos[i][1] += delta * local_mat[1][2];
+					vertexCos[i][2] += delta * local_mat[2][2];
+				}
+				else {
+					vertexCos[i][2] += delta;
+				}
 				break;
 			case MOD_DISP_DIR_RGB_XYZ:
-				vertexCos[i][0] += (texres.tr - dmd->midlevel) * strength;
-				vertexCos[i][1] += (texres.tg - dmd->midlevel) * strength;
-				vertexCos[i][2] += (texres.tb - dmd->midlevel) * strength;
+				local_vec[0] = texres.tr - dmd->midlevel;
+				local_vec[1] = texres.tg - dmd->midlevel;
+				local_vec[2] = texres.tb - dmd->midlevel;
+				if (use_global_direction) {
+					mul_transposed_mat3_m4_v3(local_mat, local_vec);
+				}
+				mul_v3_fl(local_vec, strength);
+				add_v3_v3(vertexCos[i], local_vec);
 				break;
 			case MOD_DISP_DIR_NOR:
 				vertexCos[i][0] += delta * (mvert[i].no[0] / 32767.0f);