[Bf-blender-cvs] [489c015e706] master: Fix T62891: particle even distribution is not even.

[Brecht Van Lommel]

Commit: 489c015e706cf3bcfd246a2a081664d290ec7096
Author: Brecht Van Lommel
Date:   Mon Mar 25 13:55:03 2019 +0100
Branches: master
https://developer.blender.org/rB489c015e706cf3bcfd246a2a081664d290ec7096

Fix T62891: particle even distribution is not even.

CD_ORCO coordinates are stored normalized by convention, this code path did
not store them correctly.

===================================================================

M	source/blender/blenkernel/intern/particle_distribute.c
M	source/blender/makesdna/DNA_customdata_types.h

===================================================================

diff --git a/source/blender/blenkernel/intern/particle_distribute.c b/source/blender/blenkernel/intern/particle_distribute.c
index dd0a4a24d7b..fc3c998ca1c 100644
--- a/source/blender/blenkernel/intern/particle_distribute.c
+++ b/source/blender/blenkernel/intern/particle_distribute.c
@@ -909,8 +909,12 @@ static int psys_thread_context_init_distribute(ParticleThreadContext *ctx, Parti
 		BKE_mesh_tessface_ensure(mesh);
 
 		/* we need orco for consistent distributions */
-		if (!CustomData_has_layer(&mesh->vdata, CD_ORCO))
-			CustomData_add_layer(&mesh->vdata, CD_ORCO, CD_ASSIGN, BKE_mesh_orco_verts_get(ob), mesh->totvert);
+		if (!CustomData_has_layer(&mesh->vdata, CD_ORCO)) {
+			/* Orcos are stored in normalized 0..1 range by convention. */
+			float (*orcodata)[3] = BKE_mesh_orco_verts_get(ob);
+			BKE_mesh_orco_verts_transform(mesh, orcodata, mesh->totvert, false);
+			CustomData_add_layer(&mesh->vdata, CD_ORCO, CD_ASSIGN, orcodata, mesh->totvert);
+		}
 
 		if (from == PART_FROM_VERT) {
 			MVert *mv = mesh->mvert;
@@ -966,6 +970,7 @@ static int psys_thread_context_init_distribute(ParticleThreadContext *ctx, Parti
 			MFace *mf = &mesh->mface[i];
 
 			if (orcodata) {
+				/* Transform orcos from normalized 0..1 to object space. */
 				copy_v3_v3(co1, orcodata[mf->v1]);
 				copy_v3_v3(co2, orcodata[mf->v2]);
 				copy_v3_v3(co3, orcodata[mf->v3]);
diff --git a/source/blender/makesdna/DNA_customdata_types.h b/source/blender/makesdna/DNA_customdata_types.h
index 91412044e0e..10d18684413 100644
--- a/source/blender/makesdna/DNA_customdata_types.h
+++ b/source/blender/makesdna/DNA_customdata_types.h
@@ -108,7 +108,7 @@ typedef enum CustomDataType {
 	CD_PROP_INT         = 11,
 	CD_PROP_STR         = 12,
 	CD_ORIGSPACE        = 13,  /* for modifier stack face location mapping */
-	CD_ORCO             = 14,
+	CD_ORCO             = 14,  /* undeformed vertex coordinates, normalized to 0..1 range */
 /*	CD_MTEXPOLY         = 15, */  /* deprecated */
 	CD_MLOOPUV          = 16,
 	CD_MLOOPCOL         = 17,