Alembic import: fixed bug where local matrix from Alembic was used as object matrix

[blender.git] / source / blender / alembic / intern / abc_object.cc

diff --git a/source/blender/alembic/intern/abc_object.cc b/source/blender/alembic/intern/abc_object.cc
index 0b2c8cb6b8a19b80a886a1303cd6b43b91aa109c..62042d255011d815da266df838f60fddc8fa58c5 100644 (file)
--- a/source/blender/alembic/intern/abc_object.cc
+++ b/source/blender/alembic/intern/abc_object.cc
@@ -214,7 +214,7 @@ Imath::M44d get_matrix(const IXformSchema &schema, const float time)
        return s0.getMatrix();
 }
 
-void AbcObjectReader::readObjectMatrix(const float time)
+void AbcObjectReader::setupObjectTransform(const float time)
 {
        bool is_constant = false;
 
@@ -292,6 +292,16 @@ void AbcObjectReader::read_matrix(float mat[4][4], const float time, const float
        const Imath::M44d matrix = get_matrix(schema, time);
        convert_matrix(matrix, m_object, mat, scale, has_alembic_parent);
 
+       if (has_alembic_parent) {
+               /* In this case, the matrix in Alembic is in local coordinates, so
+                * convert to world matrix. To prevent us from reading and accumulating
+                * all parent matrices in the Alembic file, we assume that the Blender
+                * parent object is already updated for the current timekey, and use its
+                * world matrix. */
+               BLI_assert(m_object->parent);
+               mul_m4_m4m4(mat, m_object->parent->obmat, mat);
+       }
+
        is_constant = schema.isConstant();
 }