Fix for #31962, changes image ignores correct aspect ratio. Made

unwrapper flush the correct aspect flag to mtpoly after unwrap. Faces
that have been unwrapped with correct aspect option will fix their
aspect each time a different image is assigned to them. I hope fix works
100%, I can't say that I really understood the bizarre aspect ratio
system.

4 files changed, 62 insertions, 13 deletions

diff --git a/source/blender/editors/uvedit/uvedit_ops.c b/source/blender/editors/uvedit/uvedit_ops.c
index 216ac61b628..05bfc8d4a2e 100644
--- a/source/blender/editors/uvedit/uvedit_ops.c
+++ b/source/blender/editors/uvedit/uvedit_ops.c
@@ -196,7 +196,15 @@ void ED_uvedit_assign_image(Main *bmain, Scene *scene, Object *obedit, Image *im
 	}
 	else {
 		/* old shading system, assign image to selected faces */
-		
+		float prev_aspect[2], fprev_aspect;
+		float aspect[2], faspect;
+
+		ED_image_uv_aspect(previma, prev_aspect, prev_aspect + 1);
+		ED_image_uv_aspect(ima, aspect, aspect + 1);
+
+		fprev_aspect = prev_aspect[0]/prev_aspect[1];
+		faspect = aspect[0]/aspect[1];
+
 		/* ensure we have a uv map */
 		if (!CustomData_has_layer(&em->bm->pdata, CD_MTEXPOLY)) {
 			BM_data_layer_add(em->bm, &em->bm->pdata, CD_MTEXPOLY);
@@ -214,6 +222,19 @@ void ED_uvedit_assign_image(Main *bmain, Scene *scene, Object *obedit, Image *im
 					
 					if (ima->id.us == 0) id_us_plus(&ima->id);
 					else id_lib_extern(&ima->id);
+
+					/* we also need to correct the aspect of uvs */
+					if(tf->unwrap & TF_CORRECT_ASPECT) {
+						BMIter liter;
+						BMLoop *l;
+
+						BM_ITER_ELEM (l, &liter, efa, BM_LOOPS_OF_FACE) {
+							MLoopUV *luv = CustomData_bmesh_get(&em->bm->ldata, l->head.data, CD_MLOOPUV);
+
+							luv->uv[0] *= fprev_aspect;
+							luv->uv[0] /= faspect;
+						}
+					}
 				}
 				else {
 					tf->tpage = NULL;
diff --git a/source/blender/editors/uvedit/uvedit_parametrizer.c b/source/blender/editors/uvedit/uvedit_parametrizer.c
index 87ff36ebf27..a2e276c09e3 100644
--- a/source/blender/editors/uvedit/uvedit_parametrizer.c
+++ b/source/blender/editors/uvedit/uvedit_parametrizer.c
@@ -145,6 +145,7 @@ typedef struct PFace {
 
 	struct PEdge *edge;
 	unsigned char flag;
+	short *unwrap_flag;
 
 } PFace;
 
@@ -232,8 +233,11 @@ typedef struct PHandle {
 
 	RNG *rng;
 	float blend;
+	char do_aspect;
 } PHandle;
 
+/* duplicate, to avoid including DNA_mesh_types.h */
+#define TF_CORRECT_ASPECT  256
 
 /* PHash
  * - special purpose hash that keeps all its elements in a single linked list.
@@ -646,6 +650,7 @@ static void p_vert_load_pin_select_uvs(PHandle *handle, PVert *v)
 static void p_flush_uvs(PHandle *handle, PChart *chart)
 {
 	PEdge *e;
+	PFace *f;
 
 	for (e = chart->edges; e; e = e->nextlink) {
 		if (e->orig_uv) {
@@ -653,6 +658,16 @@ static void p_flush_uvs(PHandle *handle, PChart *chart)
 			e->orig_uv[1] = e->vert->uv[1] / handle->aspy;
 		}
 	}
+
+	for (f = chart->faces; f; f = f->nextlink) {
+		if(f->unwrap_flag) {
+			if (handle->do_aspect) {
+				*f->unwrap_flag |= TF_CORRECT_ASPECT;
+			} else {
+				*f->unwrap_flag &= ~TF_CORRECT_ASPECT;
+			}
+		}
+	}
 }
 
 static void p_flush_uvs_blend(PHandle *handle, PChart *chart, float blend)
@@ -1042,6 +1057,7 @@ static PFace *p_face_add(PHandle *handle)
 	/* allocate */
 	f = (PFace *)BLI_memarena_alloc(handle->arena, sizeof *f);
 	f->flag = 0; // init !
+	f->unwrap_flag = NULL;
 
 	e1 = (PEdge *)BLI_memarena_alloc(handle->arena, sizeof *e1);
 	e2 = (PEdge *)BLI_memarena_alloc(handle->arena, sizeof *e2);
@@ -1068,7 +1084,7 @@ static PFace *p_face_add(PHandle *handle)
 
 static PFace *p_face_add_construct(PHandle *handle, ParamKey key, ParamKey *vkeys,
                                    float *co[3], float *uv[3], int i1, int i2, int i3,
-                                   ParamBool *pin, ParamBool *select)
+                                   ParamBool *pin, ParamBool *select, short *unwrap_flag)
 {
 	PFace *f = p_face_add(handle);
 	PEdge *e1 = f->edge, *e2 = e1->next, *e3 = e2->next;
@@ -1095,6 +1111,7 @@ static PFace *p_face_add_construct(PHandle *handle, ParamKey key, ParamKey *vkey
 
 	/* insert into hash */
 	f->u.key = key;
+	f->unwrap_flag = unwrap_flag;
 	phash_insert(handle->hash_faces, (PHashLink *)f);
 
 	e1->u.key = PHASH_edge(vkeys[i1], vkeys[i2]);
@@ -4087,6 +4104,7 @@ ParamHandle *param_construct_begin(void)
 	handle->arena = BLI_memarena_new((1 << 16), "param construct arena");
 	handle->aspx = 1.0f;
 	handle->aspy = 1.0f;
+	handle->do_aspect = FALSE;
 
 	handle->hash_verts = phash_new((PHashLink **)&handle->construction_chart->verts, 1);
 	handle->hash_edges = phash_new((PHashLink **)&handle->construction_chart->edges, 1);
@@ -4101,6 +4119,7 @@ void param_aspect_ratio(ParamHandle *handle, float aspx, float aspy)
 
 	phandle->aspx = aspx;
 	phandle->aspy = aspy;
+	phandle->do_aspect = TRUE;
 }
 
 void param_delete(ParamHandle *handle)
@@ -4131,7 +4150,7 @@ void param_delete(ParamHandle *handle)
 
 void param_face_add(ParamHandle *handle, ParamKey key, int nverts,
                     ParamKey *vkeys, float **co, float **uv,
-                    ParamBool *pin, ParamBool *select)
+                    ParamBool *pin, ParamBool *select, short *unwrap_flag)
 {
 	PHandle *phandle = (PHandle *)handle;
 
@@ -4141,16 +4160,16 @@ void param_face_add(ParamHandle *handle, ParamKey key, int nverts,
 
 	if (nverts == 4) {
 		if (p_quad_split_direction(phandle, co, vkeys)) {
-			p_face_add_construct(phandle, key, vkeys, co, uv, 0, 1, 2, pin, select);
-			p_face_add_construct(phandle, key, vkeys, co, uv, 0, 2, 3, pin, select);
+			p_face_add_construct(phandle, key, vkeys, co, uv, 0, 1, 2, pin, select, unwrap_flag);
+			p_face_add_construct(phandle, key, vkeys, co, uv, 0, 2, 3, pin, select, unwrap_flag);
 		}
 		else {
-			p_face_add_construct(phandle, key, vkeys, co, uv, 0, 1, 3, pin, select);
-			p_face_add_construct(phandle, key, vkeys, co, uv, 1, 2, 3, pin, select);
+			p_face_add_construct(phandle, key, vkeys, co, uv, 0, 1, 3, pin, select, unwrap_flag);
+			p_face_add_construct(phandle, key, vkeys, co, uv, 1, 2, 3, pin, select, unwrap_flag);
 		}
 	}
 	else if (!p_face_exists(phandle, vkeys, 0, 1, 2)) {
-		p_face_add_construct(phandle, key, vkeys, co, uv, 0, 1, 2, pin, select);
+		p_face_add_construct(phandle, key, vkeys, co, uv, 0, 1, 2, pin, select, unwrap_flag);
 	}
 }
 
diff --git a/source/blender/editors/uvedit/uvedit_parametrizer.h b/source/blender/editors/uvedit/uvedit_parametrizer.h
index 3c886367191..9a2fea0d7f9 100644
--- a/source/blender/editors/uvedit/uvedit_parametrizer.h
+++ b/source/blender/editors/uvedit/uvedit_parametrizer.h
@@ -62,7 +62,7 @@ void param_face_add(ParamHandle *handle,
 					float **co,
 					float **uv,
 					ParamBool *pin,
-					ParamBool *select);
+					ParamBool *select, short *unwrap_flag);
 
 void param_edge_set_seam(ParamHandle *handle,
 						 ParamKey *vkeys);
diff --git a/source/blender/editors/uvedit/uvedit_unwrap_ops.c b/source/blender/editors/uvedit/uvedit_unwrap_ops.c
index 0930edbe46d..1def5caad87 100644
--- a/source/blender/editors/uvedit/uvedit_unwrap_ops.c
+++ b/source/blender/editors/uvedit/uvedit_unwrap_ops.c
@@ -202,6 +202,8 @@ static ParamHandle *construct_param_handle(Scene *scene, BMEditMesh *em,
 		
 			if (aspx != aspy)
 				param_aspect_ratio(handle, aspx, aspy);
+			else
+				param_aspect_ratio(handle, 1.0, 1.0);
 		}
 	}
 	
@@ -211,6 +213,7 @@ static ParamHandle *construct_param_handle(Scene *scene, BMEditMesh *em,
 	BLI_srand(0);
 	
 	BM_ITER_MESH (efa, &iter, em->bm, BM_FACES_OF_MESH) {
+		MTexPoly *tf;
 		ScanFillVert *sf_vert, *sf_vert_last, *sf_vert_first;
 		ScanFillFace *sf_tri;
 		ParamKey key, vkeys[4];
@@ -237,6 +240,7 @@ static ParamHandle *construct_param_handle(Scene *scene, BMEditMesh *em,
 
 		key = (ParamKey)efa;
 
+		tf = CustomData_bmesh_get(&em->bm->pdata, efa->head.data, CD_MTEXPOLY);
 
 		if (efa->len == 3 || efa->len == 4) {
 			/* for quads let parametrize split, it can make better decisions
@@ -253,7 +257,7 @@ static ParamHandle *construct_param_handle(Scene *scene, BMEditMesh *em,
 				i++;
 			}
 
-			param_face_add(handle, key, i, vkeys, co, uv, pin, select);
+			param_face_add(handle, key, i, vkeys, co, uv, pin, select, &tf->unwrap);
 		}
 		else {
 			/* ngon - scanfill time! */
@@ -298,7 +302,7 @@ static ParamHandle *construct_param_handle(Scene *scene, BMEditMesh *em,
 					select[i] = uvedit_uv_select_test(em, scene, ls[i]) != 0;
 				}
 
-				param_face_add(handle, key, 3, vkeys, co, uv, pin, select);
+				param_face_add(handle, key, 3, vkeys, co, uv, pin, select, &tf->unwrap);
 			}
 
 			BLI_scanfill_end(&sf_ctx);
@@ -388,6 +392,8 @@ static ParamHandle *construct_param_handle_subsurfed(Scene *scene, BMEditMesh *e
 
 			if (aspx != aspy)
 				param_aspect_ratio(handle, aspx, aspy);
+			else
+				param_aspect_ratio(handle, 1.0, 1.0);
 		}
 	}
 
@@ -440,7 +446,8 @@ static ParamHandle *construct_param_handle_subsurfed(Scene *scene, BMEditMesh *e
 		float *co[4];
 		float *uv[4];
 		BMFace *origFace = faceMap[i];
-		
+		MTexPoly *tf;
+
 		face = subsurfedFaces + i;
 
 		if (scene->toolsettings->uv_flag & UV_SYNC_SELECTION) {
@@ -452,6 +459,8 @@ static ParamHandle *construct_param_handle_subsurfed(Scene *scene, BMEditMesh *e
 				continue;
 		}
 
+		tf = CustomData_bmesh_get(&em->bm->pdata, origFace->head.data, CD_MTEXPOLY);
+
 		/* We will not check for v4 here. Subsurfed mfaces always have 4 vertices. */
 		key = (ParamKey)face;
 		vkeys[0] = (ParamKey)face->v1;
@@ -471,7 +480,7 @@ static ParamHandle *construct_param_handle_subsurfed(Scene *scene, BMEditMesh *e
 		texface_from_original_index(origFace, origVertIndices[face->v3], &uv[2], &pin[2], &select[2], scene, em);
 		texface_from_original_index(origFace, origVertIndices[face->v4], &uv[3], &pin[3], &select[3], scene, em);
 
-		param_face_add(handle, key, 4, vkeys, co, uv, pin, select);
+		param_face_add(handle, key, 4, vkeys, co, uv, pin, select, &tf->unwrap);
 	}
 
 	/* these are calculated from original mesh too */