Math Lib: avoid having to pass a pre-calculated normal tot area_poly_v3

add normal_poly_v3

7 files changed, 40 insertions, 65 deletions

diff --git a/source/blender/blenkernel/BKE_mesh.h b/source/blender/blenkernel/BKE_mesh.h
index d6c3734fa2d..4b346b201ba 100644
--- a/source/blender/blenkernel/BKE_mesh.h
+++ b/source/blender/blenkernel/BKE_mesh.h
@@ -192,7 +192,7 @@ void BKE_mesh_calc_poly_center(
         struct MVert *mvarray, float cent[3]);
 float BKE_mesh_calc_poly_area(
         struct MPoly *mpoly, struct MLoop *loopstart,
-        struct MVert *mvarray, const float polynormal[3]);
+        struct MVert *mvarray);
 void BKE_mesh_calc_poly_angles(
         struct MPoly *mpoly, struct MLoop *loopstart,
         struct MVert *mvarray, float angles[]);
diff --git a/source/blender/blenkernel/intern/mesh_evaluate.c b/source/blender/blenkernel/intern/mesh_evaluate.c
index edd0a8540e3..fe37b9222b6 100644
--- a/source/blender/blenkernel/intern/mesh_evaluate.c
+++ b/source/blender/blenkernel/intern/mesh_evaluate.c
@@ -872,7 +872,7 @@ void BKE_mesh_calc_poly_center(MPoly *mpoly, MLoop *loopstart,
 
 /* note, passing polynormal is only a speedup so we can skip calculating it */
 float BKE_mesh_calc_poly_area(MPoly *mpoly, MLoop *loopstart,
-                              MVert *mvarray, const float polynormal[3])
+                              MVert *mvarray)
 {
 	if (mpoly->totloop == 3) {
 		return area_tri_v3(mvarray[loopstart[0].v].co,
@@ -890,22 +890,16 @@ float BKE_mesh_calc_poly_area(MPoly *mpoly, MLoop *loopstart,
 	else {
 		int i;
 		MLoop *l_iter = loopstart;
-		float area, polynorm_local[3];
+		float area;
 		float (*vertexcos)[3] = BLI_array_alloca(vertexcos, (size_t)mpoly->totloop);
-		const float *no = polynormal ? polynormal : polynorm_local;
 
 		/* pack vertex cos into an array for area_poly_v3 */
 		for (i = 0; i < mpoly->totloop; i++, l_iter++) {
 			copy_v3_v3(vertexcos[i], mvarray[l_iter->v].co);
 		}
 
-		/* need normal for area_poly_v3 as well */
-		if (polynormal == NULL) {
-			BKE_mesh_calc_poly_normal(mpoly, loopstart, mvarray, polynorm_local);
-		}
-
 		/* finally calculate the area */
-		area = area_poly_v3((const float (*)[3])vertexcos, (unsigned int)mpoly->totloop, no);
+		area = area_poly_v3((const float (*)[3])vertexcos, (unsigned int)mpoly->totloop);
 
 		return area;
 	}
diff --git a/source/blender/blenkernel/intern/object_dupli.c b/source/blender/blenkernel/intern/object_dupli.c
index b3726ebc8da..786c283cd09 100644
--- a/source/blender/blenkernel/intern/object_dupli.c
+++ b/source/blender/blenkernel/intern/object_dupli.c
@@ -693,7 +693,7 @@ static void get_dupliface_transform(MPoly *mpoly, MLoop *mloop, MVert *mvert,
 	}
 	/* scale */
 	if (use_scale) {
-		float area = BKE_mesh_calc_poly_area(mpoly, mloop, mvert, f_no);
+		float area = BKE_mesh_calc_poly_area(mpoly, mloop, mvert);
 		scale = sqrtf(area) * scale_fac;
 	}
 	else
diff --git a/source/blender/blenlib/BLI_math_geom.h b/source/blender/blenlib/BLI_math_geom.h
index 7dcee518287..3c1b89fbd44 100644
--- a/source/blender/blenlib/BLI_math_geom.h
+++ b/source/blender/blenlib/BLI_math_geom.h
@@ -49,13 +49,14 @@ void cent_quad_v3(float r[3], const float a[3], const float b[3], const float c[
 
 float normal_tri_v3(float r[3], const float a[3], const float b[3], const float c[3]);
 float normal_quad_v3(float r[3], const float a[3], const float b[3], const float c[3], const float d[3]);
+float normal_poly_v3(float r[3], const float verts[][3], unsigned int nr);
 
 MINLINE float area_tri_v2(const float a[2], const float b[2], const float c[2]);
 MINLINE float area_tri_signed_v2(const float v1[2], const float v2[2], const float v3[2]);
 float area_tri_v3(const float a[3], const float b[3], const float c[3]);
 float area_tri_signed_v3(const float v1[3], const float v2[3], const float v3[3], const float normal[3]);
 float area_quad_v3(const float a[3], const float b[3], const float c[3], const float d[3]);
-float area_poly_v3(const float verts[][3], unsigned int nr, const float normal[3]);
+float area_poly_v3(const float verts[][3], unsigned int nr);
 float area_poly_v2(const float verts[][2], unsigned int nr);
 float cotangent_tri_weight_v3(const float v1[3], const float v2[3], const float v3[3]);
 
diff --git a/source/blender/blenlib/intern/math_geom.c b/source/blender/blenlib/intern/math_geom.c
index 01dbe01d152..45e8c425f64 100644
--- a/source/blender/blenlib/intern/math_geom.c
+++ b/source/blender/blenlib/intern/math_geom.c
@@ -88,6 +88,27 @@ float normal_quad_v3(float n[3], const float v1[3], const float v2[3], const flo
 	return normalize_v3(n);
 }
 
+/**
+ * Computes the normal of a planar
+ * polygon See Graphics Gems for
+ * computing newell normal.
+ */
+float normal_poly_v3(float n[3], const float verts[][3], unsigned int nr)
+{
+	float const *v_prev = verts[nr - 1];
+	float const *v_curr = verts[0];
+	unsigned int i;
+
+	zero_v3(n);
+
+	/* Newell's Method */
+	for (i = 0; i < nr; v_prev = v_curr, v_curr = verts[++i]) {
+		add_newell_cross_v3_v3v3(n, v_prev, v_curr);
+	}
+
+	return normalize_v3(n);
+}
+
 /* only convex Quadrilaterals */
 float area_quad_v3(const float v1[3], const float v2[3], const float v3[3], const float v4[3])
 {
@@ -134,25 +155,10 @@ float area_tri_signed_v3(const float v1[3], const float v2[3], const float v3[3]
 	return area;
 }
 
-float area_poly_v3(const float verts[][3], unsigned int nr, const float normal[3])
+float area_poly_v3(const float verts[][3], unsigned int nr)
 {
-	unsigned int a;
-	int px, py;
-	const float max = axis_dominant_v3_max(&px, &py, normal);
-	float area;
-	const float *co_curr, *co_prev;
-
-	/* The Trapezium Area Rule */
-	co_prev = verts[nr - 1];
-	co_curr = verts[0];
-	area = 0.0f;
-	for (a = 0; a < nr; a++) {
-		area += (co_curr[px] - co_prev[px]) * (co_curr[py] + co_prev[py]);
-		co_prev = co_curr;
-		co_curr += 3;
-	}
-
-	return fabsf(0.5f * area / max);
+	float n[3];
+	return normal_poly_v3(n, verts, nr) * 0.5f;
 }
 
 float cross_poly_v2(const float verts[][2], unsigned int nr)
diff --git a/source/blender/bmesh/intern/bmesh_polygon.c b/source/blender/bmesh/intern/bmesh_polygon.c
index aff7d37abe9..17996176555 100644
--- a/source/blender/bmesh/intern/bmesh_polygon.c
+++ b/source/blender/bmesh/intern/bmesh_polygon.c
@@ -70,33 +70,9 @@ static bool testedgesidef(const float v1[2], const float v2[2], const float v3[2
 }
 
 /**
- * \brief COMPUTE POLY NORMAL
- *
- * Computes the normal of a planar
- * polygon See Graphics Gems for
- * computing newell normal.
- */
-static void calc_poly_normal(float normal[3], float verts[][3], int nverts)
-{
-	float const *v_prev = verts[nverts - 1];
-	float const *v_curr = verts[0];
-	float n[3] = {0.0f};
-	int i;
-
-	/* Newell's Method */
-	for (i = 0; i < nverts; v_prev = v_curr, v_curr = verts[++i]) {
-		add_newell_cross_v3_v3v3(n, v_prev, v_curr);
-	}
-
-	if (UNLIKELY(normalize_v3_v3(normal, n) == 0.0f)) {
-		normal[2] = 1.0f; /* other axis set to 0.0 */
-	}
-}
-
-/**
  * \brief COMPUTE POLY NORMAL (BMFace)
  *
- * Same as #calc_poly_normal but operates directly on a bmesh face.
+ * Same as #normal_poly_v3 but operates directly on a bmesh face.
  */
 static void bm_face_calc_poly_normal(const BMFace *f, float n[3])
 {
@@ -229,15 +205,15 @@ void BM_face_calc_tessellation(const BMFace *f, BMLoop **r_loops, unsigned int (
  */
 float BM_face_calc_area(BMFace *f)
 {
-	BMLoop *l;
-	BMIter iter;
+	BMLoop *l_iter, *l_first;
 	float (*verts)[3] = BLI_array_alloca(verts, f->len);
 	float area;
-	int i;
+	unsigned int i = 0;
 
-	BM_ITER_ELEM_INDEX (l, &iter, f, BM_LOOPS_OF_FACE, i) {
-		copy_v3_v3(verts[i], l->v->co);
-	}
+	l_iter = l_first = BM_FACE_FIRST_LOOP(f);
+	do {
+		copy_v3_v3(verts[i++], l_iter->v->co);
+	} while ((l_iter = l_iter->next) != l_first);
 
 	if (f->len == 3) {
 		area = area_tri_v3(verts[0], verts[1], verts[2]);
@@ -246,9 +222,7 @@ float BM_face_calc_area(BMFace *f)
 		area = area_quad_v3(verts[0], verts[1], verts[2], verts[3]);
 	}
 	else {
-		float normal[3];
-		calc_poly_normal(normal, verts, f->len);
-		area = area_poly_v3((const float (*)[3])verts, f->len, normal);
+		area = area_poly_v3((const float (*)[3])verts, f->len);
 	}
 
 	return area;
diff --git a/source/blender/makesrna/intern/rna_mesh.c b/source/blender/makesrna/intern/rna_mesh.c
index 4190ce466ea..8c0f9980108 100644
--- a/source/blender/makesrna/intern/rna_mesh.c
+++ b/source/blender/makesrna/intern/rna_mesh.c
@@ -398,7 +398,7 @@ static float rna_MeshPolygon_area_get(PointerRNA *ptr)
 	Mesh *me = (Mesh *)ptr->id.data;
 	MPoly *mp = (MPoly *)ptr->data;
 
-	return BKE_mesh_calc_poly_area(mp, me->mloop + mp->loopstart, me->mvert, NULL);
+	return BKE_mesh_calc_poly_area(mp, me->mloop + mp->loopstart, me->mvert);
 }
 
 static void rna_MeshTessFace_normal_get(PointerRNA *ptr, float *values)