Sculpt mode Gravity feature from GSOC 2010 by Jason Wilkins.

Reviewers: sergey, brecht, campbellbarton, jwilkins

Differential Revision: http://developer.blender.org/D89

5 files changed, 96 insertions, 0 deletions

diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index be76a8b8c88..e51b3a6f27e 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -5119,6 +5119,11 @@ static void lib_link_scene(FileData *fd, Main *main)
 			link_paint(fd, sce, &sce->toolsettings->wpaint->paint);
 			link_paint(fd, sce, &sce->toolsettings->imapaint.paint);
 			link_paint(fd, sce, &sce->toolsettings->uvsculpt->paint);
+
+			if (sce->toolsettings->sculpt)
+				sce->toolsettings->sculpt->gravity_object =
+						newlibadr_us(fd, sce->id.lib, sce->toolsettings->sculpt->gravity_object);
+
 			sce->toolsettings->skgen_template = newlibadr(fd, sce->id.lib, sce->toolsettings->skgen_template);
 			
 			for (base = sce->base.first; base; base = next) {
diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index c0f0fcf8230..14b6ab8859a 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -317,6 +317,7 @@ typedef struct StrokeCache {
 	int alt_smooth;
 
 	float plane_trim_squared;
+	float gravity_direction[3];
 
 	rcti previous_r; /* previous redraw rectangle */
 } StrokeCache;
@@ -2997,6 +2998,49 @@ static void do_scrape_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnod
 	}
 }
 
+static void do_gravity(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode, float bstrength)
+{
+	SculptSession *ss = ob->sculpt;
+	Brush *brush = BKE_paint_brush(&sd->paint);
+
+	float offset[3]/*, an[3]*/;
+	int n;
+	float gravity_vector[3];
+
+	mul_v3_v3fl(gravity_vector, ss->cache->gravity_direction, -ss->cache->radius_squared);
+
+	/* offset with as much as possible factored in already */
+	mul_v3_v3v3(offset, gravity_vector, ss->cache->scale);
+	mul_v3_fl(offset, bstrength);
+
+	/* threaded loop over nodes */
+	#pragma omp parallel for schedule(guided) if (sd->flags & SCULPT_USE_OPENMP)
+	for(n = 0; n < totnode; n++) {
+		PBVHVertexIter vd;
+		SculptBrushTest test;
+		float (*proxy)[3];
+
+		proxy = BKE_pbvh_node_add_proxy(ss->pbvh, nodes[n])->co;
+
+		sculpt_brush_test_init(ss, &test);
+
+		BKE_pbvh_vertex_iter_begin(ss->pbvh, nodes[n], vd, PBVH_ITER_UNIQUE) {
+			if (sculpt_brush_test_sq(&test, vd.co)) {
+				const float fade = tex_strength(ss, brush, vd.co, sqrt(test.dist),
+	                                            ss->cache->sculpt_normal_symm, vd.no,
+	                                            vd.fno, vd.mask ? *vd.mask : 0.0f);
+
+				mul_v3_v3fl(proxy[vd.i], offset, fade);
+
+				if(vd.mvert)
+					vd.mvert->flag |= ME_VERT_PBVH_UPDATE;
+			}
+		}
+		BKE_pbvh_vertex_iter_end;
+	}
+}
+
+
 void sculpt_vertcos_to_key(Object *ob, KeyBlock *kb, float (*vertCos)[3])
 {
 	Mesh *me = (Mesh *)ob->data;
@@ -3223,6 +3267,9 @@ static void do_brush_action(Sculpt *sd, Object *ob, Brush *brush)
 			}
 		}
 
+		if (brush->sculpt_tool != SCULPT_TOOL_MASK && sd->gravity_factor > 0.0f)
+			do_gravity(sd, ob, nodes, totnode, sd->gravity_factor);
+
 		MEM_freeN(nodes);
 
 		/* update average stroke position */
@@ -3826,6 +3873,24 @@ static void sculpt_update_cache_invariants(bContext *C, Sculpt *sd, SculptSessio
 	cache->scale[1] = max_scale / ob->size[1];
 	cache->scale[2] = max_scale / ob->size[2];
 
+	if (sd->gravity_object) {
+		Object *gravity_object = sd->gravity_object;
+		float rmat[3][3], loc[3], size[3];
+
+		/* get gravity vector in world space */
+		copy_v3_v3(cache->gravity_direction, gravity_object->obmat[2]);
+		normalize_v3(cache->gravity_direction);
+
+		/* transform to sculpted object space by inverting object rotation matrix */
+		mat4_to_loc_rot_size(loc, rmat, size, ob->obmat);
+		/* transposition of orthogonal matrix (rotation), inverts */
+		transpose_m3(rmat);
+		mul_m3_v3(rmat, cache->gravity_direction);
+	}
+	else {
+		cache->gravity_direction[0] = cache->gravity_direction[1] = 0.0;
+		cache->gravity_direction[2] = sd->gravity_factor;
+	}
 
 	cache->plane_trim_squared = brush->plane_trim * brush->plane_trim;
 
diff --git a/source/blender/makesdna/DNA_scene_types.h b/source/blender/makesdna/DNA_scene_types.h
index 86145de3291..a539f26116e 100644
--- a/source/blender/makesdna/DNA_scene_types.h
+++ b/source/blender/makesdna/DNA_scene_types.h
@@ -850,6 +850,13 @@ typedef struct Sculpt {
 
 	/* Direction used for SCULPT_OT_symmetrize operator */
 	int symmetrize_direction;
+
+	/* gravity factor for sculpting */
+	float gravity_factor;
+	int pad;
+
+	struct Object *gravity_object;
+	void *pad2;
 } Sculpt;
 
 typedef struct UvSculpt {
diff --git a/source/blender/makesrna/intern/rna_brush.c b/source/blender/makesrna/intern/rna_brush.c
index 01e8c5956ff..bd4aa050689 100644
--- a/source/blender/makesrna/intern/rna_brush.c
+++ b/source/blender/makesrna/intern/rna_brush.c
@@ -248,6 +248,12 @@ static int rna_BrushCapabilities_has_texture_angle_get(PointerRNA *ptr)
 	             MTEX_MAP_MODE_RANDOM);
 }
 
+static int rna_SculptToolCapabilities_has_gravity_get(PointerRNA *ptr)
+{
+	Brush *br = (Brush *)ptr->data;
+	return br->sculpt_tool != SCULPT_TOOL_MASK;
+}
+
 static int rna_BrushCapabilities_has_texture_angle_source_get(PointerRNA *ptr)
 {
 	Brush *br = (Brush *)ptr->data;
@@ -556,6 +562,7 @@ static void rna_def_sculpt_capabilities(BlenderRNA *brna)
 	SCULPT_TOOL_CAPABILITY(has_smooth_stroke, "Has Smooth Stroke");
 	SCULPT_TOOL_CAPABILITY(has_space_attenuation, "Has Space Attenuation");
 	SCULPT_TOOL_CAPABILITY(has_strength, "Has Strength");
+	SCULPT_TOOL_CAPABILITY(has_gravity, "Has Gravity");
 
 #undef SCULPT_CAPABILITY
 }
diff --git a/source/blender/makesrna/intern/rna_sculpt_paint.c b/source/blender/makesrna/intern/rna_sculpt_paint.c
index 6280e0833e5..402b75c9594 100644
--- a/source/blender/makesrna/intern/rna_sculpt_paint.c
+++ b/source/blender/makesrna/intern/rna_sculpt_paint.c
@@ -427,6 +427,18 @@ static void rna_def_sculpt(BlenderRNA  *brna)
 	RNA_def_property_ui_text(prop, "Detail Refine Method",
 	                         "In dynamic-topology mode, how to add or remove mesh detail");
 	RNA_def_property_update(prop, NC_SCENE | ND_TOOLSETTINGS, NULL);
+
+	prop = RNA_def_property(srna, "gravity", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_float_sdna(prop, NULL, "gravity_factor");
+	RNA_def_property_range(prop, 0.0f, 1.0f);
+	RNA_def_property_ui_range(prop, 0.0f, 1.0f, 0.1, 3);
+	RNA_def_property_ui_text(prop, "Gravity", "Amount of gravity after each dab");
+	RNA_def_property_update(prop, NC_SCENE | ND_TOOLSETTINGS, NULL);
+
+	prop = RNA_def_property(srna, "gravity_object", PROP_POINTER, PROP_NONE);
+	RNA_def_property_flag(prop, PROP_EDITABLE);
+	RNA_def_property_ui_text(prop, "Orientation", "Object whose Z axis defines orientation of gravity");
+	RNA_def_property_update(prop, NC_SCENE | ND_TOOLSETTINGS, NULL);
 }