Expose new Recast partitioning methods for navmesh generation

This patch depends on D1747, which upgrades the Recast version.  It exposes the new Recast partitioning methods in the navmesh generation.

Reviewers: campbellbarton, moguri

Reviewed By: moguri

Projects: #bf_blender

Differential Revision: https://developer.blender.org/D1748

3 files changed, 53 insertions, 12 deletions

diff --git a/source/blender/editors/mesh/mesh_navmesh.c b/source/blender/editors/mesh/mesh_navmesh.c
index 4d07d509616..b95921964eb 100644
--- a/source/blender/editors/mesh/mesh_navmesh.c
+++ b/source/blender/editors/mesh/mesh_navmesh.c
@@ -245,20 +245,41 @@ static bool buildNavMesh(const RecastData *recastParams, int nverts, float *vert
 		return false;
 	}
 
-	/* Prepare for region partitioning, by calculating distance field along the walkable surface */
-	if (!recast_buildDistanceField(chf)) {
-		recast_destroyCompactHeightfield(chf);
+	if (recastParams->partitioning == RC_PARTITION_WATERSHED) {
+		/* Prepare for region partitioning, by calculating distance field along the walkable surface */
+		if (!recast_buildDistanceField(chf)) {
+			recast_destroyCompactHeightfield(chf);
 
-		BKE_report(reports, RPT_ERROR, "Failed to build distance field");
-		return false;
-	}
+			BKE_report(reports, RPT_ERROR, "Failed to build distance field");
+			return false;
+		}
 
-	/* Partition the walkable surface into simple regions without holes */
-	if (!recast_buildRegions(chf, 0, minRegionArea, mergeRegionArea)) {
-		recast_destroyCompactHeightfield(chf);
+		/* Partition the walkable surface into simple regions without holes */
+		if (!recast_buildRegions(chf, 0, minRegionArea, mergeRegionArea)) {
+			recast_destroyCompactHeightfield(chf);
 
-		BKE_report(reports, RPT_ERROR, "Failed to build regions");
-		return false;
+			BKE_report(reports, RPT_ERROR, "Failed to build watershed regions");
+			return false;
+		}
+	}
+	else if (recastParams->partitioning == RC_PARTITION_MONOTONE) {
+		/* Partition the walkable surface into simple regions without holes */
+		/* Monotone partitioning does not need distancefield. */
+		if (!recast_buildRegionsMonotone(chf, 0, minRegionArea, mergeRegionArea)) {
+			recast_destroyCompactHeightfield(chf);
+
+			BKE_report(reports, RPT_ERROR, "Failed to build monotone regions");
+			return false;
+		}
+	}
+	else { /* RC_PARTITION_LAYERS */
+		/* Partition the walkable surface into simple regions without holes */
+		if (!recast_buildLayerRegions(chf, 0, minRegionArea)) {
+			recast_destroyCompactHeightfield(chf);
+
+			BKE_report(reports, RPT_ERROR, "Failed to build layer regions");
+			return false;
+		}
 	}
 
 	/* ** Step 5: Trace and simplify region contours ** */
diff --git a/source/blender/makesdna/DNA_scene_types.h b/source/blender/makesdna/DNA_scene_types.h
index fd37bde65ec..a8f78f6bb34 100644
--- a/source/blender/makesdna/DNA_scene_types.h
+++ b/source/blender/makesdna/DNA_scene_types.h
@@ -795,9 +795,15 @@ typedef struct RecastData {
 	int vertsperpoly;
 	float detailsampledist;
 	float detailsamplemaxerror;
-	short pad1, pad2;
+	char partitioning;
+	char pad1;
+	short pad2;
 } RecastData;
 
+#define RC_PARTITION_WATERSHED 0
+#define RC_PARTITION_MONOTONE 1
+#define RC_PARTITION_LAYERS 2
+
 typedef struct GameData {
 
 	/* standalone player */
diff --git a/source/blender/makesrna/intern/rna_scene.c b/source/blender/makesrna/intern/rna_scene.c
index 2af58a93305..94223f7f7da 100644
--- a/source/blender/makesrna/intern/rna_scene.c
+++ b/source/blender/makesrna/intern/rna_scene.c
@@ -3565,6 +3565,13 @@ static void rna_def_scene_game_recast_data(BlenderRNA *brna)
 	StructRNA *srna;
 	PropertyRNA *prop;
 
+	static EnumPropertyItem rna_enum_partitioning_items[] = {
+		{RC_PARTITION_WATERSHED, "WATERSHED", 0, "Watershed", "Classic Recast partitioning method generating the nicest tessellation"},
+		{RC_PARTITION_MONOTONE, "MONOTONE", 0, "Monotone", "Fastest navmesh generation method, may create long thin polygons"},
+		{RC_PARTITION_LAYERS, "LAYERS", 0, "Layers", "Reasonably fast method that produces better triangles than monotone partitioning"},
+		{0, NULL, 0, NULL, NULL}
+	};
+
 	srna = RNA_def_struct(brna, "SceneGameRecastData", NULL);
 	RNA_def_struct_sdna(srna, "RecastData");
 	RNA_def_struct_nested(brna, srna, "Scene");
@@ -3627,6 +3634,13 @@ static void rna_def_scene_game_recast_data(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Merged Region Size", "Minimum regions size (smaller regions will be merged)");
 	RNA_def_property_update(prop, NC_SCENE, NULL);
 
+	prop = RNA_def_property(srna, "partitioning", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_bitflag_sdna(prop, NULL, "partitioning");
+	RNA_def_property_enum_items(prop, rna_enum_partitioning_items);
+	RNA_def_property_enum_default(prop, RC_PARTITION_WATERSHED);
+	RNA_def_property_ui_text(prop, "Partitioning", "Choose partitioning method");
+	RNA_def_property_update(prop, NC_SCENE, NULL);
+
 	prop = RNA_def_property(srna, "edge_max_len", PROP_FLOAT, PROP_NONE);
 	RNA_def_property_float_sdna(prop, NULL, "edgemaxlen");
 	RNA_def_property_ui_range(prop, 0, 50, 1, 2);