Cleanup: Rename original curve object type enum

This commit renames enums related the "Curve" object type and ID type
to add `_LEGACY` to the end. The idea is to make our aspirations clearer
in the code and to avoid ambiguities between `CURVE` and `CURVES`.

Ref T95355

To summarize for the record, the plans are:
- In the short/medium term, replace the `Curve` object data type with
 `Curves`
- In the longer term (no immediate plans), use a proper data block for
  3D text and surfaces.

Differential Revision: https://developer.blender.org/D14114

4 files changed, 65 insertions, 55 deletions

diff --git a/source/blender/makesdna/DNA_ID.h b/source/blender/makesdna/DNA_ID.h
index cf11e303234..011f3618e15 100644
--- a/source/blender/makesdna/DNA_ID.h
+++ b/source/blender/makesdna/DNA_ID.h
@@ -879,7 +879,7 @@ typedef enum IDRecalcFlag {
 #define FILTER_ID_AR (1ULL << 1)
 #define FILTER_ID_BR (1ULL << 2)
 #define FILTER_ID_CA (1ULL << 3)
-#define FILTER_ID_CU (1ULL << 4)
+#define FILTER_ID_CU_LEGACY (1ULL << 4)
 #define FILTER_ID_GD (1ULL << 5)
 #define FILTER_ID_GR (1ULL << 6)
 #define FILTER_ID_IM (1ULL << 7)
@@ -912,12 +912,12 @@ typedef enum IDRecalcFlag {
 #define FILTER_ID_SIM (1ULL << 35)
 
 #define FILTER_ID_ALL \
-  (FILTER_ID_AC | FILTER_ID_AR | FILTER_ID_BR | FILTER_ID_CA | FILTER_ID_CU | FILTER_ID_GD | \
-   FILTER_ID_GR | FILTER_ID_IM | FILTER_ID_LA | FILTER_ID_LS | FILTER_ID_LT | FILTER_ID_MA | \
-   FILTER_ID_MB | FILTER_ID_MC | FILTER_ID_ME | FILTER_ID_MSK | FILTER_ID_NT | FILTER_ID_OB | \
-   FILTER_ID_PA | FILTER_ID_PAL | FILTER_ID_PC | FILTER_ID_SCE | FILTER_ID_SPK | FILTER_ID_SO | \
-   FILTER_ID_TE | FILTER_ID_TXT | FILTER_ID_VF | FILTER_ID_WO | FILTER_ID_CF | FILTER_ID_WS | \
-   FILTER_ID_LP | FILTER_ID_CV | FILTER_ID_PT | FILTER_ID_VO | FILTER_ID_SIM)
+  (FILTER_ID_AC | FILTER_ID_AR | FILTER_ID_BR | FILTER_ID_CA | FILTER_ID_CU_LEGACY | \
+   FILTER_ID_GD | FILTER_ID_GR | FILTER_ID_IM | FILTER_ID_LA | FILTER_ID_LS | FILTER_ID_LT | \
+   FILTER_ID_MA | FILTER_ID_MB | FILTER_ID_MC | FILTER_ID_ME | FILTER_ID_MSK | FILTER_ID_NT | \
+   FILTER_ID_OB | FILTER_ID_PA | FILTER_ID_PAL | FILTER_ID_PC | FILTER_ID_SCE | FILTER_ID_SPK | \
+   FILTER_ID_SO | FILTER_ID_TE | FILTER_ID_TXT | FILTER_ID_VF | FILTER_ID_WO | FILTER_ID_CF | \
+   FILTER_ID_WS | FILTER_ID_LP | FILTER_ID_CV | FILTER_ID_PT | FILTER_ID_VO | FILTER_ID_SIM)
 
 /**
  * This enum defines the index assigned to each type of IDs in the array returned by
@@ -998,7 +998,7 @@ enum {
   /* Object data types. */
   INDEX_ID_AR,
   INDEX_ID_ME,
-  INDEX_ID_CU,
+  INDEX_ID_CU_LEGACY,
   INDEX_ID_MB,
   INDEX_ID_CV,
   INDEX_ID_PT,
diff --git a/source/blender/makesdna/DNA_ID_enums.h b/source/blender/makesdna/DNA_ID_enums.h
index a6f950517eb..b0ca13615b8 100644
--- a/source/blender/makesdna/DNA_ID_enums.h
+++ b/source/blender/makesdna/DNA_ID_enums.h
@@ -40,46 +40,46 @@ enum eIconSizes {
  * and the first 2 bytes of #ID.name (for runtime checks, see #GS macro).
  */
 typedef enum ID_Type {
-  ID_SCE = MAKE_ID2('S', 'C'), /* Scene */
-  ID_LI = MAKE_ID2('L', 'I'),  /* Library */
-  ID_OB = MAKE_ID2('O', 'B'),  /* Object */
-  ID_ME = MAKE_ID2('M', 'E'),  /* Mesh */
-  ID_CU = MAKE_ID2('C', 'U'),  /* Curve */
-  ID_MB = MAKE_ID2('M', 'B'),  /* MetaBall */
-  ID_MA = MAKE_ID2('M', 'A'),  /* Material */
-  ID_TE = MAKE_ID2('T', 'E'),  /* Tex (Texture) */
-  ID_IM = MAKE_ID2('I', 'M'),  /* Image */
-  ID_LT = MAKE_ID2('L', 'T'),  /* Lattice */
-  ID_LA = MAKE_ID2('L', 'A'),  /* Light */
-  ID_CA = MAKE_ID2('C', 'A'),  /* Camera */
-  ID_IP = MAKE_ID2('I', 'P'),  /* Ipo (depreciated, replaced by FCurves) */
-  ID_KE = MAKE_ID2('K', 'E'),  /* Key (shape key) */
-  ID_WO = MAKE_ID2('W', 'O'),  /* World */
-  ID_SCR = MAKE_ID2('S', 'R'), /* Screen */
-  ID_VF = MAKE_ID2('V', 'F'),  /* VFont (Vector Font) */
-  ID_TXT = MAKE_ID2('T', 'X'), /* Text */
-  ID_SPK = MAKE_ID2('S', 'K'), /* Speaker */
-  ID_SO = MAKE_ID2('S', 'O'),  /* Sound */
-  ID_GR = MAKE_ID2('G', 'R'),  /* Collection */
-  ID_AR = MAKE_ID2('A', 'R'),  /* bArmature */
-  ID_AC = MAKE_ID2('A', 'C'),  /* bAction */
-  ID_NT = MAKE_ID2('N', 'T'),  /* bNodeTree */
-  ID_BR = MAKE_ID2('B', 'R'),  /* Brush */
-  ID_PA = MAKE_ID2('P', 'A'),  /* ParticleSettings */
-  ID_GD = MAKE_ID2('G', 'D'),  /* bGPdata, (Grease Pencil) */
-  ID_WM = MAKE_ID2('W', 'M'),  /* WindowManager */
-  ID_MC = MAKE_ID2('M', 'C'),  /* MovieClip */
-  ID_MSK = MAKE_ID2('M', 'S'), /* Mask */
-  ID_LS = MAKE_ID2('L', 'S'),  /* FreestyleLineStyle */
-  ID_PAL = MAKE_ID2('P', 'L'), /* Palette */
-  ID_PC = MAKE_ID2('P', 'C'),  /* PaintCurve */
-  ID_CF = MAKE_ID2('C', 'F'),  /* CacheFile */
-  ID_WS = MAKE_ID2('W', 'S'),  /* WorkSpace */
-  ID_LP = MAKE_ID2('L', 'P'),  /* LightProbe */
-  ID_CV = MAKE_ID2('C', 'V'),  /* Curves */
-  ID_PT = MAKE_ID2('P', 'T'),  /* PointCloud */
-  ID_VO = MAKE_ID2('V', 'O'),  /* Volume */
-  ID_SIM = MAKE_ID2('S', 'I'), /* Simulation (geometry node groups) */
+  ID_SCE = MAKE_ID2('S', 'C'),       /* Scene */
+  ID_LI = MAKE_ID2('L', 'I'),        /* Library */
+  ID_OB = MAKE_ID2('O', 'B'),        /* Object */
+  ID_ME = MAKE_ID2('M', 'E'),        /* Mesh */
+  ID_CU_LEGACY = MAKE_ID2('C', 'U'), /* Curve. ID_CV should be used in the future (see T95355). */
+  ID_MB = MAKE_ID2('M', 'B'),        /* MetaBall */
+  ID_MA = MAKE_ID2('M', 'A'),        /* Material */
+  ID_TE = MAKE_ID2('T', 'E'),        /* Tex (Texture) */
+  ID_IM = MAKE_ID2('I', 'M'),        /* Image */
+  ID_LT = MAKE_ID2('L', 'T'),        /* Lattice */
+  ID_LA = MAKE_ID2('L', 'A'),        /* Light */
+  ID_CA = MAKE_ID2('C', 'A'),        /* Camera */
+  ID_IP = MAKE_ID2('I', 'P'),        /* Ipo (depreciated, replaced by FCurves) */
+  ID_KE = MAKE_ID2('K', 'E'),        /* Key (shape key) */
+  ID_WO = MAKE_ID2('W', 'O'),        /* World */
+  ID_SCR = MAKE_ID2('S', 'R'),       /* Screen */
+  ID_VF = MAKE_ID2('V', 'F'),        /* VFont (Vector Font) */
+  ID_TXT = MAKE_ID2('T', 'X'),       /* Text */
+  ID_SPK = MAKE_ID2('S', 'K'),       /* Speaker */
+  ID_SO = MAKE_ID2('S', 'O'),        /* Sound */
+  ID_GR = MAKE_ID2('G', 'R'),        /* Collection */
+  ID_AR = MAKE_ID2('A', 'R'),        /* bArmature */
+  ID_AC = MAKE_ID2('A', 'C'),        /* bAction */
+  ID_NT = MAKE_ID2('N', 'T'),        /* bNodeTree */
+  ID_BR = MAKE_ID2('B', 'R'),        /* Brush */
+  ID_PA = MAKE_ID2('P', 'A'),        /* ParticleSettings */
+  ID_GD = MAKE_ID2('G', 'D'),        /* bGPdata, (Grease Pencil) */
+  ID_WM = MAKE_ID2('W', 'M'),        /* WindowManager */
+  ID_MC = MAKE_ID2('M', 'C'),        /* MovieClip */
+  ID_MSK = MAKE_ID2('M', 'S'),       /* Mask */
+  ID_LS = MAKE_ID2('L', 'S'),        /* FreestyleLineStyle */
+  ID_PAL = MAKE_ID2('P', 'L'),       /* Palette */
+  ID_PC = MAKE_ID2('P', 'C'),        /* PaintCurve */
+  ID_CF = MAKE_ID2('C', 'F'),        /* CacheFile */
+  ID_WS = MAKE_ID2('W', 'S'),        /* WorkSpace */
+  ID_LP = MAKE_ID2('L', 'P'),        /* LightProbe */
+  ID_CV = MAKE_ID2('C', 'V'),        /* Curves */
+  ID_PT = MAKE_ID2('P', 'T'),        /* PointCloud */
+  ID_VO = MAKE_ID2('V', 'O'),        /* Volume */
+  ID_SIM = MAKE_ID2('S', 'I'),       /* Simulation (geometry node groups) */
 } ID_Type;
 
 /* Only used as 'placeholder' in .blend files for directly linked data-blocks. */
diff --git a/source/blender/makesdna/DNA_ipo_types.h b/source/blender/makesdna/DNA_ipo_types.h
index f40fb55e72e..70ee7c99d01 100644
--- a/source/blender/makesdna/DNA_ipo_types.h
+++ b/source/blender/makesdna/DNA_ipo_types.h
@@ -272,7 +272,7 @@ typedef struct Ipo {
 #define SEQ_FAC_SPEED 2
 #define SEQ_FAC_OPACITY 3
 
-/* ********* Curve (ID_CU) *********** */
+/* ********* Curve (ID_CU_LEGACY) *********** */
 
 #define CU_TOTIPO 1
 #define CU_TOTNAM 1
diff --git a/source/blender/makesdna/DNA_object_types.h b/source/blender/makesdna/DNA_object_types.h
index 8c235f403f0..9e0bf7dcc5a 100644
--- a/source/blender/makesdna/DNA_object_types.h
+++ b/source/blender/makesdna/DNA_object_types.h
@@ -471,7 +471,8 @@ typedef struct ObHook {
 enum {
   OB_EMPTY = 0,
   OB_MESH = 1,
-  OB_CURVE = 2,
+  /** Curve object is still used but replaced by "Curves" for the future (see T95355). */
+  OB_CURVES_LEGACY = 2,
   OB_SURF = 3,
   OB_FONT = 4,
   OB_MBALL = 5,
@@ -515,17 +516,26 @@ enum {
         OB_VOLUME))
 #define OB_TYPE_SUPPORT_VGROUP(_type) (ELEM(_type, OB_MESH, OB_LATTICE, OB_GPENCIL))
 #define OB_TYPE_SUPPORT_EDITMODE(_type) \
-  (ELEM(_type, OB_MESH, OB_FONT, OB_CURVE, OB_SURF, OB_MBALL, OB_LATTICE, OB_ARMATURE, OB_CURVES))
-#define OB_TYPE_SUPPORT_PARVERT(_type) (ELEM(_type, OB_MESH, OB_SURF, OB_CURVE, OB_LATTICE))
+  (ELEM(_type, \
+        OB_MESH, \
+        OB_FONT, \
+        OB_CURVES_LEGACY, \
+        OB_SURF, \
+        OB_MBALL, \
+        OB_LATTICE, \
+        OB_ARMATURE, \
+        OB_CURVES))
+#define OB_TYPE_SUPPORT_PARVERT(_type) \
+  (ELEM(_type, OB_MESH, OB_SURF, OB_CURVES_LEGACY, OB_LATTICE))
 
 /** Matches #OB_TYPE_SUPPORT_EDITMODE. */
-#define OB_DATA_SUPPORT_EDITMODE(_type) (ELEM(_type, ID_ME, ID_CU, ID_MB, ID_LT, ID_AR))
+#define OB_DATA_SUPPORT_EDITMODE(_type) (ELEM(_type, ID_ME, ID_CU_LEGACY, ID_MB, ID_LT, ID_AR))
 
 /* is this ID type used as object data */
 #define OB_DATA_SUPPORT_ID(_id_type) \
   (ELEM(_id_type, \
         ID_ME, \
-        ID_CU, \
+        ID_CU_LEGACY, \
         ID_MB, \
         ID_LA, \
         ID_SPK, \
@@ -540,7 +550,7 @@ enum {
 
 #define OB_DATA_SUPPORT_ID_CASE \
   ID_ME: \
-  case ID_CU: \
+  case ID_CU_LEGACY: \
   case ID_MB: \
   case ID_LA: \
   case ID_SPK: \