Fix modifiers evaluation outside of depsgraph/CoW context.

Fix T58237: Exporters: Curve Modifier not applied when "apply modifiers" are selected.
Fix T58856: Python: "to_mesh" broken in 2.8.

...And many other cases... ;)

Thing is, we need target IDs to always be evaluated ones (at least I
cannot see any case where having orig ones is desired effect here).
Depsgraph/Cow system ensures us that when modifiers are evaluated by it,
but they can also be called outside of this context, e.g. when doing
binding, or object conversion...

So we need to ensure in modifiers code that we actually are always
working with eval data for those targets.

Note that I did not touch to physics modifiers, those are a bit touchy
and rather not 'fix' something there until proven broken!

1 files changed, 13 insertions, 6 deletions

diff --git a/source/blender/modifiers/intern/MOD_util.c b/source/blender/modifiers/intern/MOD_util.c
index 3210105f710..d0c4ee38112 100644
--- a/source/blender/modifiers/intern/MOD_util.c
+++ b/source/blender/modifiers/intern/MOD_util.c
@@ -63,13 +63,16 @@
 
 #include "bmesh.h"
 
-void MOD_init_texture(const Depsgraph *depsgraph, Tex *tex)
+void MOD_init_texture(MappingInfoModifierData *dmd, const ModifierEvalContext *ctx)
 {
-	if (!tex)
+	Tex *tex = (Tex *)DEG_get_evaluated_id(ctx->depsgraph, &dmd->texture->id);
+
+	if (tex == NULL) {
 		return;
+	}
 
 	if (tex->ima && BKE_image_is_animated(tex->ima)) {
-		BKE_image_user_frame_calc(&tex->iuser, DEG_get_ctime(depsgraph));
+		BKE_image_user_frame_calc(&tex->iuser, DEG_get_ctime(ctx->depsgraph));
 	}
 }
 
@@ -77,6 +80,7 @@ void MOD_init_texture(const Depsgraph *depsgraph, Tex *tex)
 /** \param cos may be NULL, in which case we use directly mesh vertices' coordinates. */
 void MOD_get_texture_coords(
         MappingInfoModifierData *dmd,
+        const ModifierEvalContext *ctx,
         Object *ob,
         Mesh *mesh,
         float (*cos)[3],
@@ -88,10 +92,13 @@ void MOD_get_texture_coords(
 	float mapob_imat[4][4];
 
 	if (texmapping == MOD_DISP_MAP_OBJECT) {
-		if (dmd->map_object)
-			invert_m4_m4(mapob_imat, dmd->map_object->obmat);
-		else /* if there is no map object, default to local */
+		if (dmd->map_object != NULL) {
+			Object *map_object = DEG_get_evaluated_object(ctx->depsgraph, dmd->map_object);
+			invert_m4_m4(mapob_imat, map_object->obmat);
+		}
+		else {/* if there is no map object, default to local */
 			texmapping = MOD_DISP_MAP_LOCAL;
+		}
 	}
 
 	/* UVs need special handling, since they come from faces */