Sculpt dyntopo: Roughed out skeleton of new brush engine API

Command Lists

* The new system will be based on command lists
  generated by (eventually) a node editor.
* For now, the lists will be hardcoded.
* Idea is to make a minimal viable
  brush engine that won't cause file breakage
  when the upgrade to node-based brushes happen.

Brush Channels

* Wrote new structures and API to wrange
  brush parameters: BrushChannel.
* Supports, floats, ints, enums, bitmasks,
  with plans for vec3 and vec4.
* This will replace UnifiedPaintStruct,
  most of the members of Brush and the
  DynTopoSettings struct.
* Brush channels can
  be mapped to various input device
  channels (e.g. pen pressure); each
  mapping has its own associated curve
  (CurveMapping instance) and bounds.

Brush channel inheritence chaining

* Brush channels can form inheritence chains
* Channel sets are stored in three places:
  in the scene toolsettings, in Brush, and in
  individual brush commands.
* Node groups will also have a channel set.
* Channels in each set can be flagged to
  inherit from the parent set.
* Inheritence happens in seperate merged
  channel sets at runtime.  The final
  Brush channels live in Brush->channels_final,
  while the final command channels live in
  BrushCommand->params_final.

16 files changed, 972 insertions, 318 deletions

diff --git a/source/blender/blenkernel/BKE_brush_engine.h b/source/blender/blenkernel/BKE_brush_engine.h
new file mode 100644
index 00000000000..5695cae3649
--- /dev/null
+++ b/source/blender/blenkernel/BKE_brush_engine.h
@@ -0,0 +1,129 @@
+#pragma once
+
+/*
+ * 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 bke
+ * \brief New brush engine for sculpt
+ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "RNA_types.h"
+
+/*
+The new brush engine is based on command lists.  These lists
+will eventually be created by a node editor.
+
+Key is the concept of BrushChannels.  A brush channel is
+a logical parameter with a type, input settings (e.g. pen),
+a falloff curve, etc.
+
+Brush channels have a concept of inheritance.  There is a
+BrushChannelSet (collection of channels) in Sculpt,
+in Brush, and in BrushCommand.  Inheritence behavior
+is controller via BrushChannel->flag.
+
+This should completely replace UnifiedPaintSettings.
+*/
+struct BrushChannel;
+
+#include "BLO_read_write.h"
+#include "DNA_sculpt_brush_types.h"
+
+typedef struct BrushMappingDef {
+  int curve;
+  bool enabled;
+  bool inv;
+  float min, max;
+  int blendmode;
+} BrushMappingDef;
+
+typedef struct BrushMappingPreset {
+  // must match order of BRUSH_MAPPING_XXX enums
+  struct BrushMappingDef pressure, xtilt, ytilt, angle, speed;
+} BrushMappingPreset;
+
+#define MAX_BRUSH_ENUM_DEF 32
+
+typedef struct BrushEnumDef {
+  EnumPropertyItem items[MAX_BRUSH_ENUM_DEF];
+} BrushEnumDef;
+
+typedef struct BrushChannelType {
+  char name[32], idname[32];
+  float min, max, soft_min, soft_max;
+  BrushMappingPreset mappings;
+
+  int type, flag;
+  int ivalue;
+  float fvalue;
+  BrushEnumDef enumdef;  // if an enum type
+} BrushChannelType;
+
+typedef struct BrushCommand {
+  int tool;
+  struct BrushChannelSet *params;
+  struct BrushChannelSet *params_final;
+  int totparam;
+} BrushCommand;
+
+typedef struct BrushCommandList {
+  BrushCommand *commands;
+  int totcommand;
+} BrushCommandList;
+
+void BKE_brush_channel_free(BrushChannel *ch);
+void BKE_brush_channel_copy(BrushChannel *dst, BrushChannel *src);
+void BKE_brush_channel_init(BrushChannel *ch, BrushChannelType *def);
+BrushChannelSet *BKE_brush_channelset_create();
+
+void BKE_brush_channelset_free(BrushChannelSet *chset);
+void BKE_brush_channelset_add(BrushChannelSet *chset, BrushChannel *ch);
+
+BrushChannel *BKE_brush_channelset_lookup(BrushChannelSet *chset, const char *idname);
+
+bool BKE_brush_channelset_has(BrushChannelSet *chset, const char *idname);
+
+void BKE_brush_channelset_add_builtin(BrushChannelSet *chset, const char *idname);
+bool BKE_brush_channelset_ensure_builtin(BrushChannelSet *chset, const char *idname);
+
+void BKE_brush_channelset_merge(BrushChannelSet *dst,
+                                BrushChannelSet *child,
+                                BrushChannelSet *parent);
+
+void BKE_brush_resolve_channels(struct Brush *brush, struct Sculpt *sd);
+int BKE_brush_channel_get_int(BrushChannelSet *chset, char *idname);
+float BKE_brush_channel_get_float(BrushChannelSet *chset, char *idname);
+float BKE_brush_channel_set_float(BrushChannelSet *chset, char *idname, float val);
+void BKE_brush_init_toolsettings(struct Sculpt *sd);
+void BKE_brush_builtin_create(struct Brush *brush, int tool);
+BrushCommandList *BKE_brush_commandlist_create();
+void BKE_brush_commandlist_free(BrushCommandList *cl);
+BrushCommand *BKE_brush_commandlist_add(BrushCommandList *cl);
+BrushCommand *BKE_brush_command_init(BrushCommand *command, int tool);
+void BKE_builtin_commandlist_create(BrushChannelSet *chset, BrushCommandList *cl, int tool);
+void BKE_brush_channelset_read(BlendDataReader *reader, BrushChannelSet *cset);
+void BKE_brush_channelset_write(BlendWriter *writer, BrushChannelSet *cset);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index c652632aca8..56a221ff09b 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -289,7 +289,8 @@ set(SRC
   intern/workspace.c
   intern/world.c
   intern/writeavi.c
-  
+  intern/brush_engine.c
+
   BKE_DerivedMesh.h
   BKE_action.h
   BKE_action.hh
@@ -451,6 +452,7 @@ set(SRC
   BKE_workspace.h
   BKE_world.h
   BKE_writeavi.h
+  BKE_brush_engine.h
 
   nla_private.h
   particle_private.h
diff --git a/source/blender/blenkernel/intern/brush.c b/source/blender/blenkernel/intern/brush.c
index 7d7b13fe872..552708722ad 100644
--- a/source/blender/blenkernel/intern/brush.c
+++ b/source/blender/blenkernel/intern/brush.c
@@ -34,6 +34,7 @@
 #include "BLT_translation.h"
 
 #include "BKE_brush.h"
+#include "BKE_brush_engine.h"
 #include "BKE_colortools.h"
 #include "BKE_context.h"
 #include "BKE_gpencil.h"
@@ -262,12 +263,21 @@ static void brush_blend_write(BlendWriter *writer, ID *id, const void *id_addres
   if (brush->gradient) {
     BLO_write_struct(writer, ColorBand, brush->gradient);
   }
+
+  if (brush->channels) {
+    BKE_brush_channelset_write(writer, brush->channels);
+  }
 }
 
 static void brush_blend_read_data(BlendDataReader *reader, ID *id)
 {
   Brush *brush = (Brush *)id;
 
+  if (brush->channels) {
+    BLO_read_data_address(reader, &brush->channels);
+    BKE_brush_channelset_read(reader, brush->channels);
+  }
+
   if (brush->dyntopo.radius_scale == 0.0f) {
     brush->dyntopo.radius_scale = 1.0f;
     brush->dyntopo.inherit |= DYNTOPO_INHERIT_RADIUS_SCALE;
diff --git a/source/blender/blenkernel/intern/brush_engine.c b/source/blender/blenkernel/intern/brush_engine.c
new file mode 100644
index 00000000000..a917c92879e
--- /dev/null
+++ b/source/blender/blenkernel/intern/brush_engine.c
@@ -0,0 +1,667 @@
+#include "MEM_guardedalloc.h"
+
+#include "BLI_alloca.h"
+#include "BLI_array.h"
+#include "BLI_bitmap.h"
+#include "BLI_compiler_attrs.h"
+#include "BLI_compiler_compat.h"
+#include "BLI_listbase.h"
+#include "BLI_math.h"
+#include "BLI_memarena.h"
+
+#include "DNA_brush_enums.h"
+#include "DNA_brush_types.h"
+#include "DNA_color_types.h"
+#include "DNA_curveprofile_types.h"
+#include "DNA_node_types.h"
+#include "DNA_sculpt_brush_types.h"
+
+#include "BKE_brush.h"
+#include "BKE_colorband.h"
+#include "BKE_colortools.h"
+#include "BKE_context.h"
+#include "BKE_node.h"
+#include "BKE_paint.h"
+
+#include "BKE_brush_engine.h"
+#include "BKE_curveprofile.h"
+
+#include "BLO_read_write.h"
+
+#define ICON_NONE -1
+
+/*
+Brush command lists.
+
+Command lists are built dynamically from
+brush flags, pen input settings, etc.
+
+Eventually they will be generated by node
+networks.  BrushCommandPreset will be
+generated from the node group inputs.
+*/
+
+/* clang-format off */
+BrushChannelType brush_builtin_channels[] = {
+  {
+    .name = "Radius",
+    .idname = "RADIUS",
+    .min = 0.001f,
+    .type = BRUSH_CHANNEL_FLOAT,
+    .max = 2048.0f,
+    .soft_min = 0.1f,
+    .soft_max = 1024.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = false},
+    }
+  },
+    {
+    .name = "Strength",
+    .idname = "STRENGTH",
+    .min = -1.0f,
+    .type = BRUSH_CHANNEL_FLOAT,
+    .max = 4.0f,
+    .soft_min = 0.0f,
+    .soft_max = 1.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = true},
+    }
+  },
+   {
+    .name = "Spacing",
+    .idname = "SPACING",
+    .min = 0.001f,
+    .type = BRUSH_CHANNEL_FLOAT,
+    .max = 4.0f,
+    .soft_min = 0.005f,
+    .soft_max = 2.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = true},
+    }
+  },
+    {
+    .name = "Autosmooth",
+    .idname = "AUTOSMOOTH",
+    .type = BRUSH_CHANNEL_FLOAT,
+    .min = -1.0f,
+    .max = 4.0f,
+    .soft_min = 0.0f,
+    .soft_max = 1.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = false, .inv = true},
+    }
+  },
+    {
+    .name = "Topology Rake",
+    .idname = "TOPOLOGY_RAKE",
+    .type = BRUSH_CHANNEL_FLOAT,
+    .min = -1.0f,
+    .max = 4.0f,
+    .soft_min = 0.0f,
+    .soft_max = 1.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = false},
+    }
+  },
+  {
+    .name = "Autosmooth Radius Scale",
+    .idname = "AUTOSMOOTH_RADIUS_SCALE",
+    .type = BRUSH_CHANNEL_FLOAT,
+    .min = 0.0001f,
+    .max = 25.0f,
+    .soft_min = 0.1f,
+    .soft_max = 4.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = false},
+    }
+  },
+  {
+    .name = "Rake Radius Scale",
+    .idname = "TOPOLOGY_RAKE_RADIUS_SCALE",
+    .type = BRUSH_CHANNEL_FLOAT,
+    .min = 0.0001f,
+    .max = 25.0f,
+    .soft_min = 0.1f,
+    .soft_max = 4.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = false},
+    }
+  },
+  {
+    .name = "Face Set Slide",
+    .idname = "FSET_SLIDE",
+    .type = BRUSH_CHANNEL_FLOAT,
+    .min = 0.0001f,
+    .max = 1.0f,
+    .soft_min = 0.1f,
+    .soft_max = 1.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = false},
+    }
+  },
+  {
+    .name = "Boundary Smooth",
+    .idname = "BOUNDARY_SMOOTH",
+    .type = BRUSH_CHANNEL_FLOAT,
+    .min = 0.0001f,
+    .max = 1.0f,
+    .soft_min = 0.1f,
+    .soft_max = 1.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = false},
+    }
+  },
+   {
+    .name = "Projection",
+    .idname = "PROJECTION",
+    .type = BRUSH_CHANNEL_FLOAT,
+    .min = 0.0001f,
+    .max = 1.0f,
+    .soft_min = 0.1f,
+    .soft_max = 1.0f,
+    .mappings = {
+        .pressure = {.curve = CURVE_PRESET_SMOOTH, .min = 0.0f, .max = 1.0f, .enabled = false},
+    }
+  },
+  {
+    .name = "Topology Rake Mode",
+    .idname = "TOPOLOGY_RAKE_MODE",
+    .type = BRUSH_CHANNEL_ENUM,
+    .enumdef = {.items = {
+      {0, "BRUSH_DIRECTION", ICON_NONE, "Stroke", "Stroke Direction"},
+      {1, "CURVATURE", ICON_NONE, "Curvature", "Follow mesh curvature"},
+      {-1, 0}
+    }}
+  },
+   {
+     .name = "Automasking",
+     .idname = "AUTOMASKING",
+     .flag = BRUSH_CHANNEL_INHERIT_IF_UNSET | BRUSH_CHANNEL_INHERIT,
+     .type = BRUSH_CHANNEL_BITMASK,
+     .enumdef = {.items = {
+         {BRUSH_AUTOMASKING_BOUNDARY_EDGES, "BOUNDARY_EDGE", ICON_NONE, "Boundary Edges", ""},
+         {BRUSH_AUTOMASKING_BOUNDARY_FACE_SETS, "BOUNDARY_FACE_SETS", ICON_NONE, "Boundary Face Sets", ""},
+         {BRUSH_AUTOMASKING_CONCAVITY, "CONCAVITY", ICON_NONE, "Concave", ""},
+         {BRUSH_AUTOMASKING_INVERT_CONCAVITY, "INVERT_CONCAVITY", ICON_NONE, "Invert Concave", "Invert Concave Map"},
+         {BRUSH_AUTOMASKING_FACE_SETS, "FACE_SETS", ICON_NONE, "Face Sets", ""},
+         {BRUSH_AUTOMASKING_TOPOLOGY, "TOPOLOGY", ICON_NONE, "Topology", ""}
+      }}
+   },
+   {
+     .name = "Disable Dyntopo",
+     .idname = "DYNTOPO_DISABLED",
+     .type = BRUSH_CHANNEL_INT,
+     .flag = BRUSH_CHANNEL_NO_MAPPINGS,
+     .ivalue = 0
+   },
+   {
+     .name = "Detail Range",
+     .idname = "DYNTOPO_DETAIL_RANGE",
+     .type = BRUSH_CHANNEL_FLOAT,
+     .min = 0.001,
+     .max = 0.99,
+     .ivalue = 0
+   },
+};
+
+/* clang-format on */
+const int builtin_channel_len = ARRAY_SIZE(brush_builtin_channels);
+
+void BKE_brush_channel_free(BrushChannel *ch)
+{
+  for (int i = 0; i < BRUSH_MAPPING_MAX; i++) {
+    BKE_curvemapping_free_data(&ch->mappings[i].curve);
+  }
+}
+
+void BKE_brush_channel_copy(BrushChannel *dst, BrushChannel *src)
+{
+  *dst = *src;
+
+  for (int i = 0; i < BRUSH_MAPPING_MAX; i++) {
+    BKE_curvemapping_copy_data(&dst->mappings[i].curve, &src->mappings[i].curve);
+  }
+}
+
+void BKE_brush_channel_init(BrushChannel *ch, BrushChannelType *def)
+{
+  memset(ch, 0, sizeof(*ch));
+
+  strcpy(ch->name, def->name);
+  strcpy(ch->idname, def->idname);
+
+  ch->flag = def->flag;
+  ch->fvalue = def->fvalue;
+  ch->ivalue = def->ivalue;
+
+  ch->def = def;
+
+  for (int i = 0; i < BRUSH_MAPPING_MAX; i++) {
+    BrushMapping *map = ch->mappings + i;
+    CurveMapping *curve = &map->curve;
+
+    BKE_curvemapping_init(curve);
+
+    float min, max;
+
+    BrushMappingDef *mdef = (&def->mappings.pressure) + i;
+
+    if (mdef->min != mdef->max) {
+      min = mdef->min;
+      max = mdef->max;
+    }
+    else {
+      min = 0.0f;
+      max = 1.0f;
+    }
+
+    if (mdef->inv) {
+      ch->mappings[i].flag |= BRUSH_MAPPING_INVERT;
+    }
+
+    map->blendmode = mdef->blendmode;
+    map->factor = 1.0f;
+
+    if (mdef->enabled) {
+      map->flag |= BRUSH_MAPPING_ENABLED;
+    }
+  }
+}
+
+BrushChannelSet *BKE_brush_channelset_create()
+{
+  return (BrushChannelSet *)MEM_callocN(sizeof(BrushChannelSet), "BrushChannelSet");
+}
+
+void BKE_brush_channelset_free(BrushChannelSet *chset)
+{
+  if (chset->channels) {
+    for (int i = 0; i < chset->totchannel; i++) {
+      BKE_brush_channel_free(chset->channels + i);
+    }
+
+    MEM_freeN(chset->channels);
+  }
+  MEM_freeN(chset);
+}
+
+void BKE_brush_channelset_add(BrushChannelSet *chset, BrushChannel *ch)
+{
+  chset->totchannel++;
+
+  if (!chset->channels) {
+    chset->channels = MEM_callocN(sizeof(BrushChannelSet) * chset->totchannel, "chset->channels");
+  }
+  else {
+    chset->channels = MEM_recallocN(chset->channels,
+                                    sizeof(BrushChannelSet) * sizeof(chset->totchannel));
+  }
+
+  memcpy(chset->channels + chset->totchannel - 1, ch, sizeof(BrushChannelSet));
+}
+
+BrushChannel *BKE_brush_channelset_lookup(BrushChannelSet *chset, const char *idname)
+{
+  for (int i = 0; i < chset->totchannel; i++) {
+    if (STREQ(chset->channels[i].idname, idname)) {
+      return chset->channels + i;
+    }
+  }
+
+  return NULL;
+}
+
+bool BKE_brush_channelset_has(BrushChannelSet *chset, const char *idname)
+{
+  return BKE_brush_channelset_lookup(chset, idname) != NULL;
+}
+
+void BKE_brush_channelset_add_builtin(BrushChannelSet *chset, const char *idname)
+{
+  BrushChannelType *def = NULL;
+
+  for (int i = 0; i < builtin_channel_len; i++) {
+    BrushChannelType *def2 = builtin_channel_len + i;
+
+    if (STREQ(def2->idname, idname)) {
+      def = def2;
+      break;
+    }
+  }
+
+  if (!def) {
+    printf("%s: Could not find brush %s\n", __func__, idname);
+    return;
+  }
+
+  BrushChannel ch;
+
+  BKE_brush_channel_init(&ch, def);
+  BKE_brush_channelset_add(chset, &ch);
+}
+
+bool BKE_brush_channelset_ensure_builtin(BrushChannelSet *chset, const char *idname)
+{
+  if (!BKE_brush_channelset_has(chset, idname)) {
+    BKE_brush_channelset_add_builtin(chset, idname);
+    return true;
+  }
+
+  return false;
+}
+
+#define ADDCH(name) BKE_brush_channelset_ensure_builtin(chset, name)
+#define GETCH(name) BKE_brush_channelset_lookup(chset, name)
+
+void BKE_brush_channelset_merge(BrushChannelSet *dst,
+                                BrushChannelSet *child,
+                                BrushChannelSet *parent)
+{
+  // first add missing channels
+
+  for (int step = 0; step < 2; step++) {
+    BrushChannelSet *chset = step ? parent : child;
+
+    for (int i = 0; i < chset->totchannel; i++) {
+      BrushChannel *ch = chset->channels + i;
+
+      if (BKE_brush_channelset_has(dst, ch->idname)) {
+        continue;
+      }
+
+      BrushChannel ch2;
+      BKE_brush_channel_copy(&ch2, ch);
+      BKE_brush_channelset_add(chset, &ch2);
+    }
+  }
+
+  for (int i = 0; i < child->totchannel; i++) {
+    BrushChannel *ch = child->channels + i;
+    BrushChannel *mch = BKE_brush_channelset_lookup(dst, ch->idname);
+    BrushChannel *pch = BKE_brush_channelset_lookup(parent, ch->name);
+
+    bool ok = ch->flag & BRUSH_CHANNEL_INHERIT;
+
+    if (ch->flag & BRUSH_CHANNEL_INHERIT) {
+      BKE_brush_channel_free(mch);
+      BKE_brush_channel_copy(mch, pch);
+      continue;
+    }
+
+    if (ch->type == BRUSH_CHANNEL_BITMASK && (ch->flag & BRUSH_CHANNEL_INHERIT_IF_UNSET)) {
+      mch->ivalue = ch->ivalue | pch->ivalue;
+    }
+  }
+}
+
+void BKE_brush_resolve_channels(Brush *brush, Sculpt *sd)
+{
+  if (brush->channels_final) {
+    BKE_brush_channelset_free(brush->channels_final);
+  }
+
+  brush->channels_final = BKE_brush_channelset_create();
+
+  BKE_brush_channelset_merge(brush->channels_final, brush->channels, sd->channels);
+
+  if (!brush->commandlist) {
+    return;
+  }
+
+  BrushCommandList *cl = brush->commandlist;
+
+  for (int i = 0; i < cl->totcommand; i++) {
+    BrushCommand *command = cl->commands + i;
+
+    if (command->params_final) {
+      BKE_brush_channelset_free(command->params_final);
+    }
+
+    command->params_final = BKE_brush_channelset_create();
+    BKE_brush_channelset_merge(command->params_final, command->params, brush->channels_final);
+  }
+}
+
+int BKE_brush_channel_get_int(BrushChannelSet *chset, char *idname)
+{
+  BrushChannel *ch = BKE_brush_channelset_lookup(chset, idname);
+
+  if (!ch) {
+    printf("%s, unknown channel %s", __func__, idname);
+    return 0;
+  }
+
+  return ch->ivalue;
+}
+
+float BKE_brush_channel_get_float(BrushChannelSet *chset, char *idname)
+{
+  BrushChannel *ch = BKE_brush_channelset_lookup(chset, idname);
+
+  if (!ch) {
+    printf("%s, unknown channel %s", __func__, idname);
+    return 0;
+  }
+
+  return ch->fvalue;
+}
+
+float BKE_brush_channel_set_float(BrushChannelSet *chset, char *idname, float val)
+{
+  BrushChannel *ch = BKE_brush_channelset_lookup(chset, idname);
+
+  if (!ch) {
+    printf("%s, unknown channel %s", __func__, idname);
+    return 0;
+  }
+
+  float old = ch->fvalue;
+
+  ch->fvalue = val;
+
+  return old;
+}
+
+void BKE_brush_init_toolsettings(Sculpt *sd)
+{
+  BrushChannelSet *chset = sd->channels = BKE_brush_channelset_create();
+
+  ADDCH("RADIUS");
+  ADDCH("STRENGTH");
+  ADDCH("AUTOMASKING");
+  ADDCH("DYNTOPO_DISABLED");
+  ADDCH("DYNTOPO_DETAIL_RANGE");
+}
+
+void BKE_brush_builtin_create(Brush *brush, int tool)
+{
+  if (brush->channels) {
+    BKE_brush_channelset_free(brush->channels);
+  }
+
+  BrushChannelSet *chset = brush->channels = BKE_brush_channelset_create();
+
+  ADDCH("RADIUS");
+  ADDCH("STRENGTH");
+  ADDCH("AUTOSMOOTH");
+  ADDCH("TOPOLOGY_RAKE");
+  ADDCH("AUTOSMOOTH_RADIUS_SCLAE");
+  ADDCH("RAKE_RADIUS_SCALE");
+
+  ADDCH("AUTOMASKING");
+
+  switch (tool) {
+    case SCULPT_TOOL_DRAW: {
+      BrushChannel *ch = GETCH("STRENGTH");
+
+      ch->mappings[BRUSH_MAPPING_PRESSURE].flag &= ~BRUSH_MAPPING_ENABLED;
+      ch->flag = BRUSH_CHANNEL_INHERIT;
+      break;
+    }
+  }
+}
+
+BrushCommandList *BKE_brush_commandlist_create()
+{
+  return MEM_callocN(sizeof(BrushCommandList), "BrushCommandList");
+}
+void BKE_brush_commandlist_free(BrushCommandList *cl)
+{
+  for (int i = 0; i < cl->totcommand; i++) {
+    BrushCommand *cmd = cl->commands + i;
+
+    if (cmd->params) {
+      BKE_brush_channelset_free(cmd->params);
+    }
+
+    if (cmd->params_final) {
+      BKE_brush_channelset_free(cmd->params_final);
+    }
+  }
+
+  MEM_SAFE_FREE(cl->commands);
+
+  MEM_freeN(cl);
+}
+BrushCommand *BKE_brush_commandlist_add(BrushCommandList *cl)
+{
+  cl->totcommand++;
+
+  if (!cl->commands) {
+    cl->commands = MEM_callocN(sizeof(BrushCommand) * cl->totcommand, "BrushCommand");
+  }
+  else {
+    cl->commands = MEM_recallocN(cl->commands, sizeof(BrushCommand) * cl->totcommand);
+  }
+
+  BrushCommand *cmd = cl->commands + cl->totcommand - 1;
+  cmd->params = BKE_brush_channelset_create();
+  cmd->params_final = NULL;
+
+  return cmd;
+}
+
+BrushCommand *BKE_brush_command_init(BrushCommand *command, int tool)
+{
+  BrushChannelSet *chset = command->params;
+
+  ADDCH("SPACING");
+
+  switch (tool) {
+    case SCULPT_TOOL_DRAW:
+      ADDCH("RADIUS");
+      ADDCH("STRENGTH");
+      break;
+    case SCULPT_TOOL_SMOOTH:
+      ADDCH("RADIUS");
+      ADDCH("STRENGTH");
+      ADDCH("FSET_SLIDE");
+      ADDCH("BOUNDARY_SMOOTH");
+      ADDCH("PROJECTION");
+      break;
+    case SCULPT_TOOL_TOPOLOGY_RAKE:
+      ADDCH("RADIUS");
+      ADDCH("STRENGTH");
+      // ADDCH("FSET_SLIDE");
+      // ADDCH("BOUNDARY_SMOOTH");
+      ADDCH("PROJECTION");
+      ADDCH("TOPOLOGY_RAKE_MODE");
+      break;
+    case SCULPT_TOOL_DYNTOPO:
+      break;
+  }
+
+  return command;
+}
+
+void BKE_builtin_commandlist_create(BrushChannelSet *chset, BrushCommandList *cl, int tool)
+{
+  BrushCommand *cmd;
+
+  cmd = BKE_brush_commandlist_add(cl);
+  BKE_brush_command_init(cmd, tool);
+
+  for (int i = 0; i < cmd->totparam; i++) {
+    // inherit from brush channels for main tool
+    cmd->params->channels[i].flag |= BRUSH_CHANNEL_INHERIT;
+  }
+
+  float radius = BKE_brush_channel_get_float(chset, "RADIUS");
+  float autosmooth_scale = BKE_brush_channel_get_float(chset, "AUTOSMOOTH_RADIUS_SCALE");
+
+  float autosmooth = BKE_brush_channel_get_float(chset, "AUTOSMOOTH");
+  if (autosmooth > 0.0f) {
+    cmd = BKE_brush_command_init(BKE_brush_commandlist_add(cl), SCULPT_TOOL_SMOOTH);
+    BKE_brush_channel_set_float(cmd->params, "STRENGTH", autosmooth);
+    BKE_brush_channel_set_float(cmd->params, "RADIUS", radius * autosmooth_scale);
+    BKE_brush_channel_set_float(
+        cmd->params, "PROJECTION", BKE_brush_channel_get_float(chset, "AUTOSMOOTH_PROJECTION"));
+  }
+}
+
+void BKE_brush_channelset_read(BlendDataReader *reader, BrushChannelSet *cset)
+{
+  BLO_read_data_address(reader, &cset->channels);
+
+  for (int i = 0; i < cset->totchannel; i++) {
+    BrushChannel *ch = cset->channels + i;
+
+    for (int j = 0; j < BRUSH_MAPPING_MAX; j++) {
+      BKE_curvemapping_blend_read(reader, &ch->mappings[j].curve);
+    }
+  }
+}
+
+void BKE_brush_channelset_write(BlendWriter *writer, BrushChannelSet *cset)
+{
+  BLO_write_struct(writer, BrushChannelSet, cset);
+  BLO_write_struct_array_by_name(writer, "BrushChannel", cset->totchannel, cset->channels);
+
+  for (int i = 0; i < cset->totchannel; i++) {
+    BrushChannel *ch = cset->channels + i;
+
+    for (int j = 0; j < BRUSH_MAPPING_MAX; j++) {
+      BKE_curvemapping_blend_write(writer, &ch->mappings[j].curve);
+    }
+  }
+}
+
+/* clang-format on */
+
+/* idea for building built-in preset node graphs:
+from brush_builder import Builder;
+
+def build(input, output):
+  input.add("Strength", "float", "strength").range(0.0, 3.0)
+  input.add("Radius", "float", "radius").range(0.01, 1024.0)
+  input.add("Autosmooth", "float", "autosmooth").range(0.0, 4.0)
+  input.add("Topology Rake", "float", "topology rake").range(0.0, 4.0)
+  input.add("Smooth Radius Scale", "float", "autosmooth_radius_scale").range(0.01, 5.0)
+  input.add("Rake Radius Scale", "float", "toporake_radius_scale").range(0.01, 5.0)
+
+  draw = input.make.tool("DRAW")
+  draw.radius = input.radius
+  draw.strength = input.strength
+
+  smooth = input.make.tool("SMOOTH")
+  smooth.radius = input.radius * input.autosmooth_radius_scale
+  smooth.strength = input.autosmooth;
+  smooth.flow = draw.outflow
+
+  rake = input.make.tool("TOPORAKE")
+  rake.radius = input.radius * input.toporake_radius_scale
+  rake.strength = input.topology;
+  rake.flow = smooth.outflow
+
+  output.out = rake.outflow
+
+preset = Builder(build)
+
+*/
+
+/*
+bNodeType sculpt_tool_node = {
+  .idname = "SculptTool",
+  .ui_name = "SculptTool",
+};*/
+/* cland-format on */
diff --git a/source/blender/blenkernel/intern/scene.c b/source/blender/blenkernel/intern/scene.c
index 10517f76b04..74fc5e6de7a 100644
--- a/source/blender/blenkernel/intern/scene.c
+++ b/source/blender/blenkernel/intern/scene.c
@@ -69,6 +69,7 @@
 #include "BKE_anim_data.h"
 #include "BKE_animsys.h"
 #include "BKE_armature.h"
+#include "BKE_brush_engine.h"
 #include "BKE_cachefile.h"
 #include "BKE_collection.h"
 #include "BKE_colortools.h"
@@ -849,6 +850,11 @@ static void scene_blend_write(BlendWriter *writer, ID *id, const void *id_addres
   }
   if (tos->sculpt) {
     BLO_write_struct(writer, Sculpt, tos->sculpt);
+
+    if (tos->sculpt->channels) {
+      BKE_brush_channelset_write(writer, tos->sculpt->channels);
+    }
+
     BKE_paint_blend_write(writer, &tos->sculpt->paint);
   }
   if (tos->uvsculpt) {
@@ -1050,6 +1056,11 @@ static void scene_blend_read_data(BlendDataReader *reader, ID *id)
     sce->toolsettings->particle.object = NULL;
     sce->toolsettings->gp_sculpt.paintcursor = NULL;
 
+    if (sce->toolsettings->sculpt && sce->toolsettings->sculpt->channels) {
+      BLO_read_data_address(reader, &sce->toolsettings->sculpt->channels);
+      BKE_brush_channelset_read(reader, sce->toolsettings->sculpt->channels);
+    }
+
     /* relink grease pencil interpolation curves */
     BLO_read_data_address(reader, &sce->toolsettings->gp_interpolate.custom_ipo);
     if (sce->toolsettings->gp_interpolate.custom_ipo) {
diff --git a/source/blender/editors/sculpt_paint/sculpt_brush_machine.c b/source/blender/editors/sculpt_paint/sculpt_brush_machine.c
index b4771bd783d..e69de29bb2d 100644
--- a/source/blender/editors/sculpt_paint/sculpt_brush_machine.c
+++ b/source/blender/editors/sculpt_paint/sculpt_brush_machine.c
@@ -1,316 +0,0 @@
-#if 1
-#  include "MEM_guardedalloc.h"
-
-#  include "BLI_alloca.h"
-#  include "BLI_array.h"
-#  include "BLI_bitmap.h"
-#  include "BLI_compiler_attrs.h"
-#  include "BLI_compiler_compat.h"
-#  include "BLI_listbase.h"
-#  include "BLI_math.h"
-#  include "BLI_memarena.h"
-
-#  include "DNA_brush_enums.h"
-#  include "DNA_brush_types.h"
-#  include "DNA_color_types.h"
-#  include "DNA_curveprofile_types.h"
-#  include "DNA_node_types.h"
-
-#  include "BKE_brush.h"
-#  include "BKE_colorband.h"
-#  include "BKE_colortools.h"
-#  include "BKE_context.h"
-#  include "BKE_node.h"
-#  include "BKE_paint.h"
-
-#  include "BKE_curveprofile.h"
-
-#  define MAX_BRUSH_COMMAND_PARAMS 16
-#  define MAX_BRUSH_CHANNEL_CURVES 3
-
-enum {
-  BRUSH_CHANNEL_RADIUS = 1 << 0,
-  BRUSH_CHANNEL_STRENGTH = 1 << 1,
-  BRUSH_CHANNEL_CLOTH_TYPE = 1 << 2,  // int
-  BRUSH_CHANNEL_RADIUS_SCALE = 1 << 3,
-  //  BRUSH_CHANNEL_ITERATIONS = 1 << 3,  // int
-  //  BRUSH_CHANNEL_BOUNDARY_TYPE = 1 << 4,
-  // BRUSH_CHANNEL_AUTOMASKING_TYPE = 1 << 5,
-  CHANNEL_CUSTOM = 1 << 20
-};
-
-typedef struct BrushChannel {
-  int type;
-  char name[32];  // for custom types
-
-  float value;
-  CurveMapping curves[MAX_BRUSH_CHANNEL_CURVES];
-  int flag;
-} BrushChannel;
-
-#  define MAX_BRUSH_ENUM_DEF 32
-
-typedef struct BrushEnumDef {
-  EnumPropertyItem items[MAX_BRUSH_ENUM_DEF];
-} BrushEnumDef;
-
-typedef struct BrushChannelType {
-  char name[32];
-  int channel;
-  float min, max, softmin, softmax;
-  int curve_presets[MAX_BRUSH_CHANNEL_CURVES];
-  int type, subtype;
-  BrushEnumDef enumdef;  // if an enum type
-} BrushChannelType;
-
-// curves
-enum { BRUSH_CHANNEL_PRESSURE, BRUSH_CHANNEL_XTILT, BRUSH_CHANNEL_YTILT };
-
-enum {
-  BRUSH_CHANNEL_FLOAT = 1 << 0,
-  BRUSH_CHANNEL_INT = 1 << 1,
-  BRUSH_CHANNEL_ENUM = 1 << 0  // subtype
-};
-
-/* BrushChannel->flag */
-enum {
-  /*float only flags*/
-  BRUSH_CHANNEL_USE_PRESSURE = 1 << 0,
-  BRUSH_CHANNEL_INV_PRESSURE = 1 << 1,
-  BRUSH_CHANNEL_USE_TILT = 1 << 2,
-};
-
-/*
-Brush command lists.
-
-Command lists are built dynamically from
-brush flags, pen input settings, etc.
-
-Eventually they will be generated by node
-networks.  BrushCommandPreset will be
-generated from the node group inputs.
-*/
-
-typedef struct BrushCommandPreset {
-  char name[64];
-  int tool;
-
-  struct {
-    char name[32];
-    int type;
-    float defval;
-    BrushChannelType *custom_type;
-  } channels[32];
-} BrushCommandPreset;
-
-/* clang-format off */
-BrushCommandPreset DrawBrush = {
-  .name = "Draw",
-  .tool = SCULPT_TOOL_DRAW,
-  .channels = {
-    {.name = "Radius", .type = BRUSH_CHANNEL_RADIUS, .defval = 50.0f},
-    {.name = "Strength", .type = BRUSH_CHANNEL_STRENGTH, .defval = 1.0f},
-    {.name = "Autosmooth", .type = BRUSH_CHANNEL_STRENGTH, .defval = 0.0f},
-    {.name = "Autosmooth Radius Scale", .type = BRUSH_CHANNEL_RADIUS_SCALE, .defval = 1.0f},
-    {.name = "Topology Rake", .type = BRUSH_CHANNEL_STRENGTH, .defval = 0.0f},
-    {.name = "Topology Rake Radius Scale", .type = BRUSH_CHANNEL_RADIUS_SCALE, .defval = 1.0f},
-    {.type = -1}
-  }
-};
-
-typedef struct BrushCommand {
-  int tool;
-  BrushChannel params[MAX_BRUSH_COMMAND_PARAMS];
-  int totparam;
-} BrushCommand;
-
-typedef struct BrushCommandList {
-  BrushCommand *commands;
-  int totcommand;
-} BrushCommandList;
-
-static BrushChannelType brush_builtin_channels[] = {
-    {.name = "Radius",
-     .channel = BRUSH_CHANNEL_RADIUS,
-     .type = BRUSH_CHANNEL_FLOAT,
-     .min = 0.001,
-     .max = 1024,
-     .softmin = 0.001,
-     .softmax = 700,
-     .curve_presets = {CURVE_PRESET_SMOOTH}},
-    {.name = "Strength",
-     .channel = BRUSH_CHANNEL_STRENGTH,
-     .type = BRUSH_CHANNEL_FLOAT,
-     .min = 0.001,
-     .max = 1024,
-     .softmin = 0.001,
-     .softmax = 700,
-     .curve_presets = {CURVE_PRESET_SMOOTH}},
-    {.name = "Cloth Deform Type",
-     .channel = BRUSH_CHANNEL_CLOTH_TYPE,
-     .type = BRUSH_CHANNEL_INT,
-     .subtype = BRUSH_CHANNEL_ENUM,
-     .enumdef =
-         {
-             {BRUSH_CLOTH_DEFORM_DRAG, "DRAG", 0, "Drag", ""},
-             {BRUSH_CLOTH_DEFORM_PUSH, "PUSH", 0, "Push", ""},
-             {BRUSH_CLOTH_DEFORM_PINCH_POINT, "PINCH_POINT", 0, "Pinch Point", ""},
-             {BRUSH_CLOTH_DEFORM_PINCH_PERPENDICULAR,
-              "PINCH_PERPENDICULAR",
-              0,
-              "Pinch Perpendicular",
-              ""},
-             {BRUSH_CLOTH_DEFORM_INFLATE, "INFLATE", 0, "Inflate", ""},
-             {BRUSH_CLOTH_DEFORM_GRAB, "GRAB", 0, "Grab", ""},
-             {BRUSH_CLOTH_DEFORM_EXPAND, "EXPAND", 0, "Expand", ""},
-             {BRUSH_CLOTH_DEFORM_SNAKE_HOOK, "SNAKE_HOOK", 0, "Snake Hook", ""},
-             {0, NULL, 0, NULL, NULL},
-         }},
-    {.name = "Radius Scale",
-     .channel = BRUSH_CHANNEL_RADIUS,
-     .type = BRUSH_CHANNEL_FLOAT,
-     .min = 0.001,
-     .max = 15.0,
-     .softmin = 0.1,
-     .softmax = 4.0,
-     .curve_presets = {CURVE_PRESET_SMOOTH}}};
-
-enum {
-  BRUSH_COMMAND_TOPOLOGY_RAKE = 500,
-  BRUSH_COMMAND_DYNTOPO = 501,
-  BRUSH_COMMAND_SMOOTH_LAP = 502,
-  BRUSH_COMMAND_SMOOTH_SURFACE = 503,
-};
-
-/* clang-format on */
-
-enum {
-  SCULPT_OP_INT = 1 << 0,
-  SCULPT_OP_FLOAT = 1 << 1,
-  SCULPT_OP_VEC2 = 1 << 2,
-  SCULPT_OP_VEC3 = 1 << 3,
-  SCULPT_OP_VEC4 = 1 << 4,
-  SCULPT_OP_VEC5 = 1 << 5,
-  SCULPT_OP_PTR = 1 << 6
-};
-
-typedef union SculptReg {
-  float f;
-  int i;
-  float v[5];
-  void *p;
-  char ch[32];
-  // BrushChannel *ch;
-} SculptReg;
-
-typedef struct SculptOpCode {
-  int code;
-  SculptReg params[16];
-} SculptOpCode;
-
-#  define SCULPT_MAXREG 32
-
-typedef struct SculptVM {
-  SculptOpCode *opcodes;
-  int totopcode;
-  SculptReg regs[SCULPT_MAXREG];
-};
-
-enum {
-  SOP_LOADF = 0,  // reg, float
-  SOP_LOADI,
-  SOP_LOADF2,   // reg, float, float
-  SOP_LOADF3,   // reg, float, float, float
-  SOP_LOADF4,   // reg, float, float, float, float
-  SOP_LOADPTR,  // reg, ptr
-
-  SOP_PUSH,         // reg
-  SOP_POP,          // reg
-  SOP_POP_DISCARD,  //
-  SOP_MUL,          // dstreg reg reg
-  SOP_ADD,          // dstreg reg reg
-  SOP_SUB,          // dstreg reg reg
-  SOP_DIV,          // dstreg reg reg
-
-  SOP_LOAD_CHANNEL_F,  // reg channel
-  SOP_LOAD_CHANNEL_I,  // reg channel
-  SOP_TOOL_EXEC,       // tool, ...
-};
-
-#  define BRUSH_VALUE_DEFAULT FLT_MAX;
-
-/* clang-format off */
-#define REG_RADIUS 10
-#define REG_STRENGTH 11
-#define REG_AUTOSMOOTH 12
-#define REG_TOPORAKE 13
-
-#define OP(op) {op},
-#define OP_I_CH(op, i1, ch1) {op, {{.i = i1}, {.ch = ch1}, {.i = -1}}},
-#define OP_I(op, i1, i2) {op, {{.i = i1}, {.i = -1}}},
-#define OP_I2(op, i1, i2) {op, {{.i = i1}, {.i = i2}, {.i = -1}}},
-#define OP_I3(op, i1, i2, i3) {op, {{.i = i1}, {.i = i2}, {.i = i3}, {.i = -1}}},
-#define OP_I4(op, i1, i2, i3, i4) {op, {{.i = i1}, {.i = i2}, {.i = i3}, {.i = i4}, {.i = -1}}},
-
-SculptOpCode preset[] = {
-  OP_I_CH(SOP_LOAD_CHANNEL_F, REG_RADIUS, "Radius")
-  OP_I_CH(SOP_LOAD_CHANNEL_F, REG_STRENGTH, "Strength")
-  OP_I3(SOP_TOOL_EXEC, SCULPT_TOOL_DRAW, REG_RADIUS, REG_STRENGTH)
-
-  OP_I_CH(SOP_LOAD_CHANNEL_F, REG_AUTOSMOOTH, "Radius")
-  OP_I_CH(SOP_LOAD_CHANNEL_F, REG_AUTOSMOOTH, "Autosmooth Radius Scale")
-  OP_I3(SOP_MUL, REG_AUTOSMOOTH, REG_AUTOSMOOTH, REG_RADIUS)
-};
-
-typedef struct GraphNode {
-  char name[32];
-  char id[32];
-
-  struct {
-    char src[32];
-    char node[32];
-    char dst[32];
-  } inputs[32];
-} GraphNode;
-
-/* node preset solution b:
-
-from brush_builder import Builder;
-
-def build(input, output):
-  input.add("Strength", "float", "strength").range(0.0, 3.0)
-  input.add("Radius", "float", "radius").range(0.01, 1024.0)
-  input.add("Autosmooth", "float", "autosmooth").range(0.0, 4.0)
-  input.add("Topology Rake", "float", "topology rake").range(0.0, 4.0)
-  input.add("Smooth Radius Scale", "float", "autosmooth_radius_scale").range(0.01, 5.0)
-  input.add("Rake Radius Scale", "float", "toporake_radius_scale").range(0.01, 5.0)
-
-  draw = input.make.tool("DRAW")
-  draw.radius = input.radius
-  draw.strength = input.strength
-
-  smooth = input.make.tool("SMOOTH")
-  smooth.radius = input.radius * input.autosmooth_radius_scale
-  smooth.strength = input.autosmooth;
-  smooth.flow = draw.outflow
-
-  rake = input.make.tool("TOPORAKE")
-  rake.radius = input.radius * input.toporake_radius_scale
-  rake.strength = input.topology;
-  rake.flow = smooth.outflow
-
-  output.out = rake.outflow
-
-preset = Builder(build)
-
-*/
-
-
-
-/*
-bNodeType sculpt_tool_node = {
-  .idname = "SculptTool",
-  .ui_name = "SculptTool",
-};*/
-/* cland-format on */
-#endif
diff --git a/source/blender/makesdna/DNA_brush_enums.h b/source/blender/makesdna/DNA_brush_enums.h
index 2f838513bf0..6f0b09614c7 100644
--- a/source/blender/makesdna/DNA_brush_enums.h
+++ b/source/blender/makesdna/DNA_brush_enums.h
@@ -477,7 +477,10 @@ typedef enum eBrushSculptTool {
   SCULPT_TOOL_DISPLACEMENT_ERASER = 31,
   SCULPT_TOOL_DISPLACEMENT_SMEAR = 32,
   SCULPT_TOOL_VCOL_BOUNDARY = 33,
-  SCULPT_TOOL_UV_SMOOTH = 34
+  SCULPT_TOOL_UV_SMOOTH = 34,
+
+  SCULPT_TOOL_TOPOLOGY_RAKE = 35,
+  SCULPT_TOOL_DYNTOPO = 36
 } eBrushSculptTool;
 
 /* Brush.uv_sculpt_tool */
diff --git a/source/blender/makesdna/DNA_brush_types.h b/source/blender/makesdna/DNA_brush_types.h
index 84809daeb00..42135992477 100644
--- a/source/blender/makesdna/DNA_brush_types.h
+++ b/source/blender/makesdna/DNA_brush_types.h
@@ -36,6 +36,8 @@ struct CurveMapping;
 struct Image;
 struct MTex;
 struct Material;
+struct BrushChannelSet;
+struct BrushCommandList;
 
 typedef struct BrushClone {
   /** Image for clone tool. */
@@ -399,6 +401,12 @@ typedef struct Brush {
   struct BrushGpencilSettings *gpencil_settings;
 
   DynTopoSettings dyntopo, cached_dyntopo;
+
+  /* new brush engine stuff */
+
+  struct BrushChannelSet *channels;
+  struct BrushChannelSet *channels_final;
+  struct BrushCommandList *commandlist;
 } Brush;
 
 /* Struct to hold palette colors for sorting. */
diff --git a/source/blender/makesdna/DNA_scene_types.h b/source/blender/makesdna/DNA_scene_types.h
index 3538d1d01f5..70146d02108 100644
--- a/source/blender/makesdna/DNA_scene_types.h
+++ b/source/blender/makesdna/DNA_scene_types.h
@@ -971,6 +971,8 @@ typedef struct ParticleEditSettings {
 /* ------------------------------------------- */
 /* Sculpt */
 
+struct BrushChannelSet;
+
 /* Sculpt */
 typedef struct Sculpt {
   Paint paint;
@@ -1004,6 +1006,7 @@ typedef struct Sculpt {
   struct Object *gravity_object;
   float dyntopo_radius_scale;
   int _pad[1];
+  struct BrushChannelSet *channels;
 } Sculpt;
 
 typedef struct UvSculpt {
diff --git a/source/blender/makesdna/DNA_sculpt_brush_types.h b/source/blender/makesdna/DNA_sculpt_brush_types.h
new file mode 100644
index 00000000000..eba4c89c5b5
--- /dev/null
+++ b/source/blender/makesdna/DNA_sculpt_brush_types.h
@@ -0,0 +1,84 @@
+/*
+ * 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) 2011 Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup DNA
+ *
+ * Structs used for the sculpt brush system
+ */
+#pragma once
+
+typedef struct BrushMapping {
+  char name[64];
+  CurveMapping curve;
+  float factor;
+  short blendmode;
+  short input_channel;
+  int flag, _pad[1];
+} BrushMapping;
+
+typedef struct BrushChannel {
+  char idname[64];
+  char name[64];
+
+  struct BrushChannelType *def;
+
+  float fvalue;
+  int ivalue;
+  BrushMapping mappings[5];  // should always be BRUSH_MAPPING_MAX
+
+  int type, flag;
+} BrushChannel;
+
+typedef struct BrushChannelSet {
+  BrushChannel *channels;
+  int totchannel, _pad[1];
+} BrushChannelSet;
+
+// mapping flags
+enum { BRUSH_MAPPING_ENABLED = 1 << 0, BRUSH_MAPPING_INVERT = 1 << 1 };
+
+// mapping types
+enum {
+  BRUSH_MAPPING_PRESSURE = 0,
+  BRUSH_MAPPING_XTILT = 1,
+  BRUSH_MAPPING_YTILT = 2,
+  BRUSH_MAPPING_ANGLE = 3,
+  BRUSH_MAPPING_SPEED = 4,
+  BRUSH_MAPPING_MAX = 5  // see BrushChannel.mappings
+};
+
+static_assert(offsetof(BrushChannel, type) - offsetof(BrushChannel, mappings) ==
+                  sizeof(BrushMapping) * BRUSH_MAPPING_MAX,
+              "BrushChannel.mappings must == BRUSH_MAPPING_MAX");
+
+// BrushChannel->flag
+enum {
+  BRUSH_CHANNEL_INHERIT = 1 << 0,
+  BRUSH_CHANNEL_INHERIT_IF_UNSET = 1 << 1,
+  BRUSH_CHANNEL_NO_MAPPINGS = 1 << 2
+};
+
+// BrushChannelType->type
+enum {
+  BRUSH_CHANNEL_FLOAT = 1 << 0,
+  BRUSH_CHANNEL_INT = 1 << 1,
+  BRUSH_CHANNEL_ENUM = 1 << 2,
+  BRUSH_CHANNEL_BITMASK = 1 << 3,
+};
diff --git a/source/blender/makesdna/intern/CMakeLists.txt b/source/blender/makesdna/intern/CMakeLists.txt
index db34cf83fa9..41e95205ccc 100644
--- a/source/blender/makesdna/intern/CMakeLists.txt
+++ b/source/blender/makesdna/intern/CMakeLists.txt
@@ -165,6 +165,7 @@ set(SRC
   ../DNA_view3d_defaults.h
   ../DNA_volume_defaults.h
   ../DNA_world_defaults.h
+  ../DNA_sculpt_brush_types.h
 )
 
 set(LIB
diff --git a/source/blender/makesdna/intern/makesdna.c b/source/blender/makesdna/intern/makesdna.c
index 061c3462a69..6822c48380a 100644
--- a/source/blender/makesdna/intern/makesdna.c
+++ b/source/blender/makesdna/intern/makesdna.c
@@ -142,6 +142,7 @@ static const char *includefiles[] = {
     "DNA_simulation_types.h",
     "DNA_pointcache_types.h",
     "DNA_asset_types.h",
+    "DNA_sculpt_brush_types.h",
 
     /* see comment above before editing! */
 
@@ -1666,6 +1667,7 @@ int main(int argc, char **argv)
 #include "DNA_rigidbody_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_screen_types.h"
+#include "DNA_sculpt_brush_types.h"
 #include "DNA_sdna_types.h"
 #include "DNA_sequence_types.h"
 #include "DNA_session_uuid_types.h"
diff --git a/source/blender/makesrna/intern/CMakeLists.txt b/source/blender/makesrna/intern/CMakeLists.txt
index 7e6d0aea2ee..cdbd7fe023e 100644
--- a/source/blender/makesrna/intern/CMakeLists.txt
+++ b/source/blender/makesrna/intern/CMakeLists.txt
@@ -34,6 +34,7 @@ set(DEFSRC
   rna_attribute.c
   rna_boid.c
   rna_brush.c
+  rna_brush_engine.c
   rna_cachefile.c
   rna_camera.c
   rna_cloth.c
diff --git a/source/blender/makesrna/intern/makesrna.c b/source/blender/makesrna/intern/makesrna.c
index 36f19907080..eda878f378d 100644
--- a/source/blender/makesrna/intern/makesrna.c
+++ b/source/blender/makesrna/intern/makesrna.c
@@ -4365,6 +4365,7 @@ static RNAProcessItem PROCESS_ITEMS[] = {
     {"rna_asset.c", NULL, RNA_def_asset},
     {"rna_boid.c", NULL, RNA_def_boid},
     {"rna_brush.c", NULL, RNA_def_brush},
+    {"rna_brush_engine.c", NULL, RNA_def_brush_engine},
     {"rna_cachefile.c", NULL, RNA_def_cachefile},
     {"rna_camera.c", "rna_camera_api.c", RNA_def_camera},
     {"rna_cloth.c", NULL, RNA_def_cloth},
diff --git a/source/blender/makesrna/intern/rna_brush_engine.c b/source/blender/makesrna/intern/rna_brush_engine.c
new file mode 100644
index 00000000000..2c4011b956b
--- /dev/null
+++ b/source/blender/makesrna/intern/rna_brush_engine.c
@@ -0,0 +1,47 @@
+/*
+ * 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.
+ */
+
+/** \file
+ * \ingroup RNA
+ */
+
+#include <stdlib.h>
+
+#include "DNA_brush_types.h"
+#include "DNA_gpencil_types.h"
+#include "DNA_material_types.h"
+#include "DNA_object_types.h"
+#include "DNA_scene_types.h"
+#include "DNA_texture_types.h"
+#include "DNA_workspace_types.h"
+
+#include "BLI_math.h"
+
+#include "RNA_define.h"
+#include "RNA_enum_types.h"
+
+#include "rna_internal.h"
+
+#include "IMB_imbuf.h"
+
+#include "WM_types.h"
+
+#ifdef RNA_RUNTIME
+#endif
+
+void RNA_def_brush_engine(BlenderRNA *brna)
+{
+}
diff --git a/source/blender/makesrna/intern/rna_internal.h b/source/blender/makesrna/intern/rna_internal.h
index 0bb76fd933a..157ec9fbd90 100644
--- a/source/blender/makesrna/intern/rna_internal.h
+++ b/source/blender/makesrna/intern/rna_internal.h
@@ -156,6 +156,7 @@ void RNA_def_attribute(struct BlenderRNA *brna);
 void RNA_def_asset(struct BlenderRNA *brna);
 void RNA_def_boid(struct BlenderRNA *brna);
 void RNA_def_brush(struct BlenderRNA *brna);
+void RNA_def_brush_engine(struct BlenderRNA *brna);
 void RNA_def_cachefile(struct BlenderRNA *brna);
 void RNA_def_camera(struct BlenderRNA *brna);
 void RNA_def_cloth(struct BlenderRNA *brna);