Cleanup: CacheFile, use double precision for time

Both the Alembic and USD libraries use double precision floating
point numbers internally to store time. However the Alembic I/O
code defaulted to floats even though Blender's Scene FPS, which is
generally used for look ups, is stored using a double type. Such
downcasts could lead to imprecise lookups, and would cause
compilation warnings (at least on MSVC).

This modifies the Alembic exporter and importer to make use of
doubles for the current scene time, and only downcasting to float
at the very last steps (e.g. for vertex interpolation). For the
importer, doubles are also used for computing interpolation weights,
as it is based on a time offset.

Although the USD code already used doubles internally, floats were used
at the C API level. Those were replaced as well.

Differential Revision: https://developer.blender.org/D13855

15 files changed, 57 insertions, 55 deletions

diff --git a/source/blender/blenkernel/BKE_cachefile.h b/source/blender/blenkernel/BKE_cachefile.h
index 41a0ad3f763..fd559abf7f2 100644
--- a/source/blender/blenkernel/BKE_cachefile.h
+++ b/source/blender/blenkernel/BKE_cachefile.h
@@ -35,7 +35,7 @@ bool BKE_cachefile_filepath_get(const struct Main *bmain,
                                 const struct CacheFile *cache_file,
                                 char r_filename[1024]);
 
-float BKE_cachefile_time_offset(const struct CacheFile *cache_file, float time, float fps);
+double BKE_cachefile_time_offset(const struct CacheFile *cache_file, double time, double fps);
 
 /* Modifiers and constraints open and free readers through these. */
 void BKE_cachefile_reader_open(struct CacheFile *cache_file,
diff --git a/source/blender/blenkernel/intern/cachefile.c b/source/blender/blenkernel/intern/cachefile.c
index 338c74d550c..6b6b7223a0b 100644
--- a/source/blender/blenkernel/intern/cachefile.c
+++ b/source/blender/blenkernel/intern/cachefile.c
@@ -395,8 +395,8 @@ bool BKE_cachefile_filepath_get(const Main *bmain,
   if (cache_file->is_sequence && BLI_path_frame_get(r_filepath, &fframe, &frame_len)) {
     Scene *scene = DEG_get_evaluated_scene(depsgraph);
     const float ctime = BKE_scene_ctime_get(scene);
-    const float fps = (((double)scene->r.frs_sec) / (double)scene->r.frs_sec_base);
-    const float frame = BKE_cachefile_time_offset(cache_file, ctime, fps);
+    const double fps = (((double)scene->r.frs_sec) / (double)scene->r.frs_sec_base);
+    const int frame = (int)BKE_cachefile_time_offset(cache_file, (double)ctime, fps);
 
     char ext[32];
     BLI_path_frame_strip(r_filepath, ext);
@@ -410,10 +410,10 @@ bool BKE_cachefile_filepath_get(const Main *bmain,
   return true;
 }
 
-float BKE_cachefile_time_offset(const CacheFile *cache_file, const float time, const float fps)
+double BKE_cachefile_time_offset(const CacheFile *cache_file, const double time, const double fps)
 {
-  const float time_offset = cache_file->frame_offset / fps;
-  const float frame = (cache_file->override_frame ? cache_file->frame : time);
+  const double time_offset = (double)cache_file->frame_offset / fps;
+  const double frame = (cache_file->override_frame ? (double)cache_file->frame : time);
   return cache_file->is_sequence ? frame : frame / fps - time_offset;
 }
 
diff --git a/source/blender/blenkernel/intern/constraint.c b/source/blender/blenkernel/intern/constraint.c
index fc3f84778f8..0bab3d826fd 100644
--- a/source/blender/blenkernel/intern/constraint.c
+++ b/source/blender/blenkernel/intern/constraint.c
@@ -5417,7 +5417,7 @@ static void transformcache_evaluate(bConstraint *con, bConstraintOb *cob, ListBa
   }
 
   const float frame = DEG_get_ctime(cob->depsgraph);
-  const float time = BKE_cachefile_time_offset(cache_file, frame, FPS);
+  const double time = BKE_cachefile_time_offset(cache_file, (double)frame, FPS);
 
   if (!data->reader || !STREQ(data->reader_object_path, data->object_path)) {
     STRNCPY(data->reader_object_path, data->object_path);
diff --git a/source/blender/io/alembic/ABC_alembic.h b/source/blender/io/alembic/ABC_alembic.h
index d0c10bd7f76..d7d3adefc33 100644
--- a/source/blender/io/alembic/ABC_alembic.h
+++ b/source/blender/io/alembic/ABC_alembic.h
@@ -96,14 +96,14 @@ void ABC_free_handle(struct CacheArchiveHandle *handle);
 
 void ABC_get_transform(struct CacheReader *reader,
                        float r_mat_world[4][4],
-                       float time,
+                       double time,
                        float scale);
 
 /* Either modifies existing_mesh in-place or constructs a new mesh. */
 struct Mesh *ABC_read_mesh(struct CacheReader *reader,
                            struct Object *ob,
                            struct Mesh *existing_mesh,
-                           float time,
+                           double time,
                            const char **err_str,
                            int read_flags,
                            const char *velocity_name,
@@ -112,7 +112,7 @@ struct Mesh *ABC_read_mesh(struct CacheReader *reader,
 bool ABC_mesh_topology_changed(struct CacheReader *reader,
                                struct Object *ob,
                                const struct Mesh *existing_mesh,
-                               float time,
+                               double time,
                                const char **err_str);
 
 void ABC_CacheReader_incref(struct CacheReader *reader);
diff --git a/source/blender/io/alembic/exporter/abc_export_capi.cc b/source/blender/io/alembic/exporter/abc_export_capi.cc
index 53e8cee3a0a..c1ff7df0c37 100644
--- a/source/blender/io/alembic/exporter/abc_export_capi.cc
+++ b/source/blender/io/alembic/exporter/abc_export_capi.cc
@@ -134,7 +134,7 @@ static void export_startjob(void *customdata,
 
       /* Update the scene for the next frame to render. */
       scene->r.cfra = static_cast<int>(frame);
-      scene->r.subframe = frame - scene->r.cfra;
+      scene->r.subframe = static_cast<float>(frame - scene->r.cfra);
       BKE_scene_graph_update_for_newframe(data->depsgraph);
 
       CLOG_INFO(&LOG, 2, "Exporting frame %.2f", frame);
diff --git a/source/blender/io/alembic/intern/abc_customdata.h b/source/blender/io/alembic/intern/abc_customdata.h
index 74a6ca41a85..0ddba866016 100644
--- a/source/blender/io/alembic/intern/abc_customdata.h
+++ b/source/blender/io/alembic/intern/abc_customdata.h
@@ -48,8 +48,8 @@ struct CDStreamConfig {
   Mesh *mesh;
   void *(*add_customdata_cb)(Mesh *mesh, const char *name, int data_type);
 
-  float weight;
-  float time;
+  double weight;
+  Alembic::Abc::chrono_t time;
   int timesample_index;
   bool use_vertex_interpolation;
   Alembic::AbcGeom::index_t index;
@@ -79,8 +79,8 @@ struct CDStreamConfig {
         pack_uvs(false),
         mesh(NULL),
         add_customdata_cb(NULL),
-        weight(0.0f),
-        time(0.0f),
+        weight(0.0),
+        time(0.0),
         index(0),
         ceil_index(0),
         modifier_error_message(NULL)
diff --git a/source/blender/io/alembic/intern/abc_reader_mesh.cc b/source/blender/io/alembic/intern/abc_reader_mesh.cc
index 47f4dd2ea5d..f2daae4b90b 100644
--- a/source/blender/io/alembic/intern/abc_reader_mesh.cc
+++ b/source/blender/io/alembic/intern/abc_reader_mesh.cc
@@ -121,7 +121,7 @@ struct AbcMeshData {
 static void read_mverts_interp(MVert *mverts,
                                const P3fArraySamplePtr &positions,
                                const P3fArraySamplePtr &ceil_positions,
-                               const float weight)
+                               const double weight)
 {
   float tmp[3];
   for (int i = 0; i < positions->size(); i++) {
@@ -129,7 +129,7 @@ static void read_mverts_interp(MVert *mverts,
     const Imath::V3f &floor_pos = (*positions)[i];
     const Imath::V3f &ceil_pos = (*ceil_positions)[i];
 
-    interp_v3_v3v3(tmp, floor_pos.getValue(), ceil_pos.getValue(), weight);
+    interp_v3_v3v3(tmp, floor_pos.getValue(), ceil_pos.getValue(), static_cast<float>(weight));
     copy_zup_from_yup(mvert.co, tmp);
 
     mvert.bweight = 0;
diff --git a/source/blender/io/alembic/intern/abc_reader_object.cc b/source/blender/io/alembic/intern/abc_reader_object.cc
index dac0890e7c5..a698eeca8f1 100644
--- a/source/blender/io/alembic/intern/abc_reader_object.cc
+++ b/source/blender/io/alembic/intern/abc_reader_object.cc
@@ -97,7 +97,9 @@ void AbcObjectReader::object(Object *ob)
   m_object = ob;
 }
 
-static Imath::M44d blend_matrices(const Imath::M44d &m0, const Imath::M44d &m1, const float weight)
+static Imath::M44d blend_matrices(const Imath::M44d &m0,
+                                  const Imath::M44d &m1,
+                                  const double weight)
 {
   float mat0[4][4], mat1[4][4], ret[4][4];
 
@@ -108,16 +110,16 @@ static Imath::M44d blend_matrices(const Imath::M44d &m0, const Imath::M44d &m1,
 
   convert_matrix_datatype(m0, mat0);
   convert_matrix_datatype(m1, mat1);
-  interp_m4_m4m4(ret, mat0, mat1, weight);
+  interp_m4_m4m4(ret, mat0, mat1, static_cast<float>(weight));
   return convert_matrix_datatype(ret);
 }
 
-Imath::M44d get_matrix(const IXformSchema &schema, const float time)
+Imath::M44d get_matrix(const IXformSchema &schema, const chrono_t time)
 {
   Alembic::AbcGeom::index_t i0, i1;
   Alembic::AbcGeom::XformSample s0, s1;
 
-  const float weight = get_weight_and_index(
+  const double weight = get_weight_and_index(
       time, schema.getTimeSampling(), schema.getNumSamples(), i0, i1);
 
   schema.get(s0, Alembic::AbcGeom::ISampleSelector(i0));
@@ -148,7 +150,7 @@ bool AbcObjectReader::topology_changed(const Mesh * /*existing_mesh*/,
   return false;
 }
 
-void AbcObjectReader::setupObjectTransform(const float time)
+void AbcObjectReader::setupObjectTransform(const chrono_t time)
 {
   bool is_constant = false;
   float transform_from_alembic[4][4];
@@ -214,7 +216,7 @@ Alembic::AbcGeom::IXform AbcObjectReader::xform()
 }
 
 void AbcObjectReader::read_matrix(float r_mat[4][4] /* local matrix */,
-                                  const float time,
+                                  const chrono_t time,
                                   const float scale,
                                   bool &is_constant)
 {
diff --git a/source/blender/io/alembic/intern/abc_reader_object.h b/source/blender/io/alembic/intern/abc_reader_object.h
index 5898d1bd529..6c57f32045b 100644
--- a/source/blender/io/alembic/intern/abc_reader_object.h
+++ b/source/blender/io/alembic/intern/abc_reader_object.h
@@ -143,7 +143,7 @@ class AbcObjectReader {
                                 const Alembic::Abc::ISampleSelector &sample_sel);
 
   /** Reads the object matrix and sets up an object transform if animated. */
-  void setupObjectTransform(float time);
+  void setupObjectTransform(chrono_t time);
 
   void addCacheModifier();
 
@@ -154,13 +154,13 @@ class AbcObjectReader {
   void incref();
   void decref();
 
-  void read_matrix(float r_mat[4][4], float time, float scale, bool &is_constant);
+  void read_matrix(float r_mat[4][4], chrono_t time, float scale, bool &is_constant);
 
  protected:
   /** Determine whether we can inherit our parent's XForm. */
   void determine_inherits_xform();
 };
 
-Imath::M44d get_matrix(const Alembic::AbcGeom::IXformSchema &schema, float time);
+Imath::M44d get_matrix(const Alembic::AbcGeom::IXformSchema &schema, chrono_t time);
 
 }  // namespace blender::io::alembic
diff --git a/source/blender/io/alembic/intern/abc_util.cc b/source/blender/io/alembic/intern/abc_util.cc
index a253cb62a6d..90f73d25c22 100644
--- a/source/blender/io/alembic/intern/abc_util.cc
+++ b/source/blender/io/alembic/intern/abc_util.cc
@@ -73,7 +73,7 @@ Imath::M44d convert_matrix_datatype(float mat[4][4])
 
   for (int i = 0; i < 4; i++) {
     for (int j = 0; j < 4; j++) {
-      m[i][j] = mat[i][j];
+      m[i][j] = static_cast<double>(mat[i][j]);
     }
   }
 
@@ -112,35 +112,35 @@ bool has_property(const Alembic::Abc::ICompoundProperty &prop, const std::string
   return prop.getPropertyHeader(name) != nullptr;
 }
 
-using index_time_pair_t = std::pair<Alembic::AbcCoreAbstract::index_t, float>;
+using index_time_pair_t = std::pair<Alembic::AbcCoreAbstract::index_t, Alembic::AbcGeom::chrono_t>;
 
-float get_weight_and_index(float time,
-                           const Alembic::AbcCoreAbstract::TimeSamplingPtr &time_sampling,
-                           int samples_number,
-                           Alembic::AbcGeom::index_t &i0,
-                           Alembic::AbcGeom::index_t &i1)
+double get_weight_and_index(Alembic::AbcGeom::chrono_t time,
+                            const Alembic::AbcCoreAbstract::TimeSamplingPtr &time_sampling,
+                            int samples_number,
+                            Alembic::AbcGeom::index_t &i0,
+                            Alembic::AbcGeom::index_t &i1)
 {
   samples_number = std::max(samples_number, 1);
 
   index_time_pair_t t0 = time_sampling->getFloorIndex(time, samples_number);
   i0 = i1 = t0.first;
 
-  if (samples_number == 1 || (fabs(time - t0.second) < 0.0001f)) {
-    return 0.0f;
+  if (samples_number == 1 || (fabs(time - t0.second) < 0.0001)) {
+    return 0.0;
   }
 
   index_time_pair_t t1 = time_sampling->getCeilIndex(time, samples_number);
   i1 = t1.first;
 
   if (i0 == i1) {
-    return 0.0f;
+    return 0.0;
   }
 
-  const float bias = (time - t0.second) / (t1.second - t0.second);
+  const double bias = (time - t0.second) / (t1.second - t0.second);
 
-  if (fabs(1.0f - bias) < 0.0001f) {
+  if (fabs(1.0 - bias) < 0.0001) {
     i0 = i1;
-    return 0.0f;
+    return 0.0;
   }
 
   return bias;
diff --git a/source/blender/io/alembic/intern/abc_util.h b/source/blender/io/alembic/intern/abc_util.h
index a8479b3d27b..4db90820757 100644
--- a/source/blender/io/alembic/intern/abc_util.h
+++ b/source/blender/io/alembic/intern/abc_util.h
@@ -79,11 +79,11 @@ void get_min_max_time(const Alembic::AbcGeom::IObject &object,
 
 bool has_property(const Alembic::Abc::ICompoundProperty &prop, const std::string &name);
 
-float get_weight_and_index(float time,
-                           const Alembic::AbcCoreAbstract::TimeSamplingPtr &time_sampling,
-                           int samples_number,
-                           Alembic::AbcGeom::index_t &i0,
-                           Alembic::AbcGeom::index_t &i1);
+double get_weight_and_index(Alembic::AbcCoreAbstract::chrono_t time,
+                            const Alembic::AbcCoreAbstract::TimeSamplingPtr &time_sampling,
+                            int samples_number,
+                            Alembic::AbcGeom::index_t &i0,
+                            Alembic::AbcGeom::index_t &i1);
 
 AbcObjectReader *create_reader(const Alembic::AbcGeom::IObject &object, ImportSettings &settings);
 
diff --git a/source/blender/io/alembic/intern/alembic_capi.cc b/source/blender/io/alembic/intern/alembic_capi.cc
index c9c982aad6c..fe459ce4370 100644
--- a/source/blender/io/alembic/intern/alembic_capi.cc
+++ b/source/blender/io/alembic/intern/alembic_capi.cc
@@ -497,7 +497,7 @@ static void import_startjob(void *user_data, short *stop, short *do_update, floa
   chrono_t min_time = std::numeric_limits<chrono_t>::max();
   chrono_t max_time = std::numeric_limits<chrono_t>::min();
 
-  ISampleSelector sample_sel(0.0f);
+  ISampleSelector sample_sel(0.0);
   std::vector<AbcObjectReader *>::iterator iter;
   for (iter = data->readers.begin(); iter != data->readers.end(); ++iter) {
     AbcObjectReader *reader = *iter;
@@ -555,7 +555,7 @@ static void import_startjob(void *user_data, short *stop, short *do_update, floa
   i = 0;
   for (iter = data->readers.begin(); iter != data->readers.end(); ++iter) {
     AbcObjectReader *reader = *iter;
-    reader->setupObjectTransform(0.0f);
+    reader->setupObjectTransform(0.0);
 
     *data->progress = 0.7f + 0.3f * (++i / size);
     *data->do_update = true;
@@ -724,7 +724,7 @@ bool ABC_import(bContext *C,
 
 /* ************************************************************************** */
 
-void ABC_get_transform(CacheReader *reader, float r_mat_world[4][4], float time, float scale)
+void ABC_get_transform(CacheReader *reader, float r_mat_world[4][4], double time, float scale)
 {
   if (!reader) {
     return;
@@ -775,7 +775,7 @@ static AbcObjectReader *get_abc_reader(CacheReader *reader, Object *ob, const ch
   return abc_reader;
 }
 
-static ISampleSelector sample_selector_for_time(float time)
+static ISampleSelector sample_selector_for_time(chrono_t time)
 {
   /* kFloorIndex is used to be compatible with non-interpolating
    * properties; they use the floor. */
@@ -785,7 +785,7 @@ static ISampleSelector sample_selector_for_time(float time)
 Mesh *ABC_read_mesh(CacheReader *reader,
                     Object *ob,
                     Mesh *existing_mesh,
-                    const float time,
+                    const double time,
                     const char **err_str,
                     const int read_flag,
                     const char *velocity_name,
@@ -804,7 +804,7 @@ Mesh *ABC_read_mesh(CacheReader *reader,
 bool ABC_mesh_topology_changed(CacheReader *reader,
                                Object *ob,
                                const Mesh *existing_mesh,
-                               const float time,
+                               const double time,
                                const char **err_str)
 {
   AbcObjectReader *abc_reader = get_abc_reader(reader, ob, err_str);
diff --git a/source/blender/io/usd/intern/usd_capi_import.cc b/source/blender/io/usd/intern/usd_capi_import.cc
index e5083700d7d..58cd7d5014e 100644
--- a/source/blender/io/usd/intern/usd_capi_import.cc
+++ b/source/blender/io/usd/intern/usd_capi_import.cc
@@ -423,7 +423,7 @@ static USDPrimReader *get_usd_reader(CacheReader *reader, Object * /* ob */, con
 struct Mesh *USD_read_mesh(struct CacheReader *reader,
                            struct Object *ob,
                            struct Mesh *existing_mesh,
-                           const float time,
+                           const double time,
                            const char **err_str,
                            const int read_flag)
 {
@@ -437,7 +437,7 @@ struct Mesh *USD_read_mesh(struct CacheReader *reader,
 }
 
 bool USD_mesh_topology_changed(
-    CacheReader *reader, Object *ob, Mesh *existing_mesh, const float time, const char **err_str)
+    CacheReader *reader, Object *ob, Mesh *existing_mesh, const double time, const char **err_str)
 {
   USDGeomReader *usd_reader = dynamic_cast<USDGeomReader *>(get_usd_reader(reader, ob, err_str));
 
diff --git a/source/blender/io/usd/usd.h b/source/blender/io/usd/usd.h
index edc802159b1..e63cd0a4e04 100644
--- a/source/blender/io/usd/usd.h
+++ b/source/blender/io/usd/usd.h
@@ -94,14 +94,14 @@ void USD_get_transform(struct CacheReader *reader, float r_mat[4][4], float time
 struct Mesh *USD_read_mesh(struct CacheReader *reader,
                            struct Object *ob,
                            struct Mesh *existing_mesh,
-                           float time,
+                           double time,
                            const char **err_str,
                            int read_flag);
 
 bool USD_mesh_topology_changed(struct CacheReader *reader,
                                struct Object *ob,
                                struct Mesh *existing_mesh,
-                               float time,
+                               double time,
                                const char **err_str);
 
 struct CacheReader *CacheReader_open_usd_object(struct CacheArchiveHandle *handle,
diff --git a/source/blender/modifiers/intern/MOD_meshsequencecache.cc b/source/blender/modifiers/intern/MOD_meshsequencecache.cc
index eadfdcf5baa..7dbd4c5b260 100644
--- a/source/blender/modifiers/intern/MOD_meshsequencecache.cc
+++ b/source/blender/modifiers/intern/MOD_meshsequencecache.cc
@@ -154,7 +154,7 @@ static Mesh *modifyMesh(ModifierData *md, const ModifierEvalContext *ctx, Mesh *
   Scene *scene = DEG_get_evaluated_scene(ctx->depsgraph);
   CacheFile *cache_file = mcmd->cache_file;
   const float frame = DEG_get_ctime(ctx->depsgraph);
-  const float time = BKE_cachefile_time_offset(cache_file, frame, FPS);
+  const double time = BKE_cachefile_time_offset(cache_file, (double)frame, FPS);
   const char *err_str = nullptr;
 
   if (!mcmd->reader || !STREQ(mcmd->reader_object_path, mcmd->object_path)) {