Cleanup: move animation snap utilities to a separate compilation unit

The snap functions of animation editors were scattered in
`transform_mode` and `transform_snap`.

9 files changed, 175 insertions, 144 deletions

diff --git a/source/blender/editors/transform/CMakeLists.txt b/source/blender/editors/transform/CMakeLists.txt
index ad0a330f0f4..e9efed3cd61 100644
--- a/source/blender/editors/transform/CMakeLists.txt
+++ b/source/blender/editors/transform/CMakeLists.txt
@@ -101,6 +101,7 @@ set(SRC
   transform_ops.c
   transform_orientations.c
   transform_snap.c
+  transform_snap_animation.c
   transform_snap_object.c
   transform_snap_sequencer.c
 
diff --git a/source/blender/editors/transform/transform_convert_graph.c b/source/blender/editors/transform/transform_convert_graph.c
index a6cbbb299ac..c0acdd89b02 100644
--- a/source/blender/editors/transform/transform_convert_graph.c
+++ b/source/blender/editors/transform/transform_convert_graph.c
@@ -41,6 +41,8 @@
 
 #include "transform.h"
 #include "transform_convert.h"
+#include "transform_snap.h"
+
 #include "transform_mode.h"
 
 typedef struct TransDataGraph {
diff --git a/source/blender/editors/transform/transform_convert_nla.c b/source/blender/editors/transform/transform_convert_nla.c
index f96f2e93bbc..4d98b7a489f 100644
--- a/source/blender/editors/transform/transform_convert_nla.c
+++ b/source/blender/editors/transform/transform_convert_nla.c
@@ -42,6 +42,8 @@
 
 #include "transform.h"
 #include "transform_convert.h"
+#include "transform_snap.h"
+
 #include "transform_mode.h"
 
 /** Used for NLA transform (stored in #TransData.extra pointer). */
diff --git a/source/blender/editors/transform/transform_mode.c b/source/blender/editors/transform/transform_mode.c
index 362ee179e7d..8df95222fa1 100644
--- a/source/blender/editors/transform/transform_mode.c
+++ b/source/blender/editors/transform/transform_mode.c
@@ -1068,102 +1068,6 @@ void ElementResize(const TransInfo *t,
 /** \} */
 
 /* -------------------------------------------------------------------- */
-/** \name Transform (Frame Utils)
- * \{ */
-
-/**
- * This function returns the snapping 'mode' for Animation Editors only.
- * We cannot use the standard snapping due to NLA-strip scaling complexities.
- *
- * TODO: these modifier checks should be key-mappable.
- */
-short getAnimEdit_SnapMode(TransInfo *t)
-{
-  short autosnap = SACTSNAP_OFF;
-
-  if (t->spacetype == SPACE_ACTION) {
-    SpaceAction *saction = (SpaceAction *)t->area->spacedata.first;
-
-    if (saction) {
-      autosnap = saction->autosnap;
-    }
-  }
-  else if (t->spacetype == SPACE_GRAPH) {
-    SpaceGraph *sipo = (SpaceGraph *)t->area->spacedata.first;
-
-    if (sipo) {
-      autosnap = sipo->autosnap;
-    }
-  }
-  else if (t->spacetype == SPACE_NLA) {
-    SpaceNla *snla = (SpaceNla *)t->area->spacedata.first;
-
-    if (snla) {
-      autosnap = snla->autosnap;
-    }
-  }
-  else {
-    autosnap = SACTSNAP_OFF;
-  }
-
-  /* toggle autosnap on/off
-   * - when toggling on, prefer nearest frame over 1.0 frame increments
-   */
-  if (t->modifiers & MOD_SNAP_INVERT) {
-    if (autosnap) {
-      autosnap = SACTSNAP_OFF;
-    }
-    else {
-      autosnap = SACTSNAP_FRAME;
-    }
-  }
-
-  return autosnap;
-}
-
-/* This function is used by Animation Editor specific transform functions to do
- * the Snap Keyframe to Nearest Frame/Marker
- */
-void doAnimEdit_SnapFrame(
-    TransInfo *t, TransData *td, TransData2D *td2d, AnimData *adt, short autosnap)
-{
-  if (autosnap != SACTSNAP_OFF) {
-    float val;
-
-    /* convert frame to nla-action time (if needed) */
-    if (adt && (t->spacetype != SPACE_SEQ)) {
-      val = BKE_nla_tweakedit_remap(adt, *(td->val), NLATIME_CONVERT_MAP);
-    }
-    else {
-      val = *(td->val);
-    }
-
-    snapFrameTransform(t, autosnap, true, val, &val);
-
-    /* convert frame out of nla-action time */
-    if (adt && (t->spacetype != SPACE_SEQ)) {
-      *(td->val) = BKE_nla_tweakedit_remap(adt, val, NLATIME_CONVERT_UNMAP);
-    }
-    else {
-      *(td->val) = val;
-    }
-  }
-
-  /* If the handles are to be moved too
-   * (as side-effect of keyframes moving, to keep the general effect)
-   * offset them by the same amount so that the general angles are maintained
-   * (i.e. won't change while handles are free-to-roam and keyframes are snap-locked).
-   */
-  if ((td->flag & TD_MOVEHANDLE1) && td2d->h1) {
-    td2d->h1[0] = td2d->ih1[0] + *td->val - td->ival;
-  }
-  if ((td->flag & TD_MOVEHANDLE2) && td2d->h2) {
-    td2d->h2[0] = td2d->ih2[0] + *td->val - td->ival;
-  }
-}
-/** \} */
-
-/* -------------------------------------------------------------------- */
 /** \name Transform Mode Initialization
  * \{ */
 
diff --git a/source/blender/editors/transform/transform_mode.h b/source/blender/editors/transform/transform_mode.h
index 027fb6b6982..d8601000ddb 100644
--- a/source/blender/editors/transform/transform_mode.h
+++ b/source/blender/editors/transform/transform_mode.h
@@ -63,9 +63,6 @@ void ElementResize(const TransInfo *t,
                    const TransDataContainer *tc,
                    TransData *td,
                    const float mat[3][3]);
-short getAnimEdit_SnapMode(TransInfo *t);
-void doAnimEdit_SnapFrame(
-    TransInfo *t, TransData *td, TransData2D *td2d, struct AnimData *adt, short autosnap);
 void transform_mode_init(TransInfo *t, struct wmOperator *op, const int mode);
 void transform_mode_default_modal_orientation_set(TransInfo *t, int type);
 
diff --git a/source/blender/editors/transform/transform_mode_timescale.c b/source/blender/editors/transform/transform_mode_timescale.c
index 98ffc0abbd4..4123663e849 100644
--- a/source/blender/editors/transform/transform_mode_timescale.c
+++ b/source/blender/editors/transform/transform_mode_timescale.c
@@ -40,6 +40,8 @@
 
 #include "transform.h"
 #include "transform_convert.h"
+#include "transform_snap.h"
+
 #include "transform_mode.h"
 
 /* -------------------------------------------------------------------- */
diff --git a/source/blender/editors/transform/transform_snap.c b/source/blender/editors/transform/transform_snap.c
index 656a1e5d9c7..ea08c8912e9 100644
--- a/source/blender/editors/transform/transform_snap.c
+++ b/source/blender/editors/transform/transform_snap.c
@@ -1461,47 +1461,9 @@ bool snapNodesTransform(
 /** \} */
 
 /* -------------------------------------------------------------------- */
-/** \name snap Frames
+/** \name snap Grid
  * \{ */
 
-/* This function is used by Animation Editor specific transform functions to do
- * the Snap Keyframe to Nearest Frame/Marker
- */
-void snapFrameTransform(TransInfo *t,
-                        const eAnimEdit_AutoSnap autosnap,
-                        const bool is_frame_value,
-                        const float delta,
-                        float *r_val)
-{
-  double val = delta;
-  switch (autosnap) {
-    case SACTSNAP_STEP:
-    case SACTSNAP_FRAME:
-      val = floor(val + 0.5);
-      break;
-    case SACTSNAP_MARKER:
-      /* snap to nearest marker */
-      /* TODO: need some more careful checks for where data comes from. */
-      val = ED_markers_find_nearest_marker_time(&t->scene->markers, (float)val);
-      break;
-    case SACTSNAP_SECOND:
-    case SACTSNAP_TSTEP: {
-      /* second step */
-      const Scene *scene = t->scene;
-      const double secf = FPS;
-      val = floor((val / secf) + 0.5);
-      if (is_frame_value) {
-        val *= secf;
-      }
-      break;
-    }
-    case SACTSNAP_OFF: {
-      break;
-    }
-  }
-  *r_val = (float)val;
-}
-
 static void snap_grid_apply(
     TransInfo *t, const int max_index, const float grid_dist, const float loc[3], float r_out[3])
 {
diff --git a/source/blender/editors/transform/transform_snap.h b/source/blender/editors/transform/transform_snap.h
index 6dfaeab93e6..20cc590d7cc 100644
--- a/source/blender/editors/transform/transform_snap.h
+++ b/source/blender/editors/transform/transform_snap.h
@@ -45,12 +45,6 @@ bool snapNodesTransform(struct TransInfo *t,
                         float r_loc[2],
                         float *r_dist_px,
                         char *r_node_border);
-void snapFrameTransform(struct TransInfo *t,
-                        const eAnimEdit_AutoSnap autosnap,
-                        const bool is_frame_value,
-                        const float delta,
-                        /* return args */
-                        float *r_val);
 
 bool transformModeUseSnap(const TransInfo *t);
 
@@ -86,3 +80,14 @@ struct TransSeqSnapData *transform_snap_sequencer_data_alloc(const TransInfo *t)
 void transform_snap_sequencer_data_free(struct TransSeqSnapData *data);
 bool transform_snap_sequencer_calc(struct TransInfo *t);
 void transform_snap_sequencer_apply_translate(TransInfo *t, float *vec);
+
+/* transform_snap_animation.c */
+short getAnimEdit_SnapMode(TransInfo *t);
+void snapFrameTransform(struct TransInfo *t,
+                        const eAnimEdit_AutoSnap autosnap,
+                        const bool is_frame_value,
+                        const float delta,
+                        /* return args */
+                        float *r_val);
+void doAnimEdit_SnapFrame(
+    TransInfo *t, TransData *td, TransData2D *td2d, struct AnimData *adt, short autosnap);
diff --git a/source/blender/editors/transform/transform_snap_animation.c b/source/blender/editors/transform/transform_snap_animation.c
new file mode 100644
index 00000000000..ac7c47e408f
--- /dev/null
+++ b/source/blender/editors/transform/transform_snap_animation.c
@@ -0,0 +1,156 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup edtransform
+ */
+
+#include "DNA_anim_types.h"
+
+#include "BLI_math.h"
+
+#include "BKE_context.h"
+#include "BKE_nla.h"
+
+#include "ED_markers.h"
+#include "ED_screen.h"
+
+#include "transform.h"
+#include "transform_snap.h"
+
+/* -------------------------------------------------------------------- */
+/** \name Snappint in Anim Editors
+ * \{ */
+
+/**
+ * This function returns the snapping 'mode' for Animation Editors only.
+ * We cannot use the standard snapping due to NLA-strip scaling complexities.
+ *
+ * TODO: these modifier checks should be key-mappable.
+ */
+short getAnimEdit_SnapMode(TransInfo *t)
+{
+  short autosnap = SACTSNAP_OFF;
+
+  if (t->spacetype == SPACE_ACTION) {
+    SpaceAction *saction = (SpaceAction *)t->area->spacedata.first;
+
+    if (saction) {
+      autosnap = saction->autosnap;
+    }
+  }
+  else if (t->spacetype == SPACE_GRAPH) {
+    SpaceGraph *sipo = (SpaceGraph *)t->area->spacedata.first;
+
+    if (sipo) {
+      autosnap = sipo->autosnap;
+    }
+  }
+  else if (t->spacetype == SPACE_NLA) {
+    SpaceNla *snla = (SpaceNla *)t->area->spacedata.first;
+
+    if (snla) {
+      autosnap = snla->autosnap;
+    }
+  }
+  else {
+    autosnap = SACTSNAP_OFF;
+  }
+
+  /* toggle autosnap on/off
+   * - when toggling on, prefer nearest frame over 1.0 frame increments
+   */
+  if (t->modifiers & MOD_SNAP_INVERT) {
+    if (autosnap) {
+      autosnap = SACTSNAP_OFF;
+    }
+    else {
+      autosnap = SACTSNAP_FRAME;
+    }
+  }
+
+  return autosnap;
+}
+
+void snapFrameTransform(TransInfo *t,
+                        const eAnimEdit_AutoSnap autosnap,
+                        const bool is_frame_value,
+                        const float delta,
+                        /* return args */
+                        float *r_val)
+{
+  double val = delta;
+  switch (autosnap) {
+    case SACTSNAP_STEP:
+    case SACTSNAP_FRAME:
+      val = floor(val + 0.5);
+      break;
+    case SACTSNAP_MARKER:
+      /* snap to nearest marker */
+      /* TODO: need some more careful checks for where data comes from. */
+      val = ED_markers_find_nearest_marker_time(&t->scene->markers, (float)val);
+      break;
+    case SACTSNAP_SECOND:
+    case SACTSNAP_TSTEP: {
+      /* second step */
+      const Scene *scene = t->scene;
+      const double secf = FPS;
+      val = floor((val / secf) + 0.5);
+      if (is_frame_value) {
+        val *= secf;
+      }
+      break;
+    }
+    case SACTSNAP_OFF: {
+      break;
+    }
+  }
+  *r_val = (float)val;
+}
+
+/* This function is used by Animation Editor specific transform functions to do
+ * the Snap Keyframe to Nearest Frame/Marker
+ */
+void doAnimEdit_SnapFrame(
+    TransInfo *t, TransData *td, TransData2D *td2d, AnimData *adt, short autosnap)
+{
+  if (autosnap != SACTSNAP_OFF) {
+    float val;
+
+    /* convert frame to nla-action time (if needed) */
+    if (adt && (t->spacetype != SPACE_SEQ)) {
+      val = BKE_nla_tweakedit_remap(adt, *(td->val), NLATIME_CONVERT_MAP);
+    }
+    else {
+      val = *(td->val);
+    }
+
+    snapFrameTransform(t, autosnap, true, val, &val);
+
+    /* convert frame out of nla-action time */
+    if (adt && (t->spacetype != SPACE_SEQ)) {
+      *(td->val) = BKE_nla_tweakedit_remap(adt, val, NLATIME_CONVERT_UNMAP);
+    }
+    else {
+      *(td->val) = val;
+    }
+  }
+}
+
+/** \} */