Move image paint brush to its own compile unit.

4 files changed, 425 insertions, 379 deletions

diff --git a/source/blender/editors/sculpt_paint/CMakeLists.txt b/source/blender/editors/sculpt_paint/CMakeLists.txt
index c1febe5c86b..de7888aa1e8 100644
--- a/source/blender/editors/sculpt_paint/CMakeLists.txt
+++ b/source/blender/editors/sculpt_paint/CMakeLists.txt
@@ -30,6 +30,7 @@ set(SRC
   paint_curve_undo.c
   paint_hide.c
   paint_image.cc
+  paint_image_ops_paint.cc
   paint_image_2d.c
   paint_image_2d_curve_mask.cc
   paint_image_proj.c
diff --git a/source/blender/editors/sculpt_paint/paint_image.cc b/source/blender/editors/sculpt_paint/paint_image.cc
index eda686d808d..9413f872c3a 100644
--- a/source/blender/editors/sculpt_paint/paint_image.cc
+++ b/source/blender/editors/sculpt_paint/paint_image.cc
@@ -286,7 +286,7 @@ static bool image_paint_poll_ex(bContext *C, bool check_tool)
   return false;
 }
 
-static bool image_paint_poll(bContext *C)
+bool image_paint_poll(bContext *C)
 {
   return image_paint_poll_ex(C, true);
 }
@@ -312,24 +312,6 @@ static bool image_paint_2d_clone_poll(bContext *C)
 }
 
 /************************ paint operator ************************/
-enum class eTexPaintMode {
-  _2D,
-  _3D_PROJECT,
-};
-
-struct PaintOperation {
-  eTexPaintMode mode;
-
-  void *stroke_handle;
-
-  float prevmouse[2];
-  float startmouse[2];
-  double starttime;
-
-  wmPaintCursor *cursor;
-  ViewContext vc;
-};
-
 bool paint_use_opacity_masking(Brush *brush)
 {
   return ((brush->flag & BRUSH_AIRBRUSH) || (brush->flag & BRUSH_DRAG_DOT) ||
@@ -419,366 +401,6 @@ void paint_brush_exit_tex(Brush *brush)
   }
 }
 
-static void gradient_draw_line(bContext *UNUSED(C), int x, int y, void *customdata)
-{
-  PaintOperation *pop = (PaintOperation *)customdata;
-
-  if (pop) {
-    GPU_line_smooth(true);
-    GPU_blend(GPU_BLEND_ALPHA);
-
-    GPUVertFormat *format = immVertexFormat();
-    uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_I32, 2, GPU_FETCH_INT_TO_FLOAT);
-
-    ARegion *region = pop->vc.region;
-
-    immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
-
-    GPU_line_width(4.0);
-    immUniformColor4ub(0, 0, 0, 255);
-
-    immBegin(GPU_PRIM_LINES, 2);
-    immVertex2i(pos, x, y);
-    immVertex2i(
-        pos, pop->startmouse[0] + region->winrct.xmin, pop->startmouse[1] + region->winrct.ymin);
-    immEnd();
-
-    GPU_line_width(2.0);
-    immUniformColor4ub(255, 255, 255, 255);
-
-    immBegin(GPU_PRIM_LINES, 2);
-    immVertex2i(pos, x, y);
-    immVertex2i(
-        pos, pop->startmouse[0] + region->winrct.xmin, pop->startmouse[1] + region->winrct.ymin);
-    immEnd();
-
-    immUnbindProgram();
-
-    GPU_blend(GPU_BLEND_NONE);
-    GPU_line_smooth(false);
-  }
-}
-
-static PaintOperation *texture_paint_init(bContext *C, wmOperator *op, const float mouse[2])
-{
-  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
-  Scene *scene = CTX_data_scene(C);
-  ToolSettings *settings = scene->toolsettings;
-  PaintOperation *pop = MEM_cnew<PaintOperation>("PaintOperation"); /* caller frees */
-  Brush *brush = BKE_paint_brush(&settings->imapaint.paint);
-  int mode = RNA_enum_get(op->ptr, "mode");
-  ED_view3d_viewcontext_init(C, &pop->vc, depsgraph);
-
-  copy_v2_v2(pop->prevmouse, mouse);
-  copy_v2_v2(pop->startmouse, mouse);
-
-  /* initialize from context */
-  if (CTX_wm_region_view3d(C)) {
-    ViewLayer *view_layer = CTX_data_view_layer(C);
-    Object *ob = OBACT(view_layer);
-    bool uvs, mat, tex, stencil;
-    if (!ED_paint_proj_mesh_data_check(scene, ob, &uvs, &mat, &tex, &stencil)) {
-      ED_paint_data_warning(op->reports, uvs, mat, tex, stencil);
-      MEM_delete(pop);
-      WM_event_add_notifier(C, NC_SCENE | ND_TOOLSETTINGS, nullptr);
-      return nullptr;
-    }
-    pop->mode = eTexPaintMode::_3D_PROJECT;
-    pop->stroke_handle = paint_proj_new_stroke(C, ob, mouse, mode);
-  }
-  else {
-    pop->mode = eTexPaintMode::_2D;
-    pop->stroke_handle = paint_2d_new_stroke(C, op, mode);
-  }
-
-  if (!pop->stroke_handle) {
-    MEM_delete(pop);
-    return nullptr;
-  }
-
-  if ((brush->imagepaint_tool == PAINT_TOOL_FILL) && (brush->flag & BRUSH_USE_GRADIENT)) {
-    pop->cursor = WM_paint_cursor_activate(
-        SPACE_TYPE_ANY, RGN_TYPE_ANY, image_paint_poll, gradient_draw_line, pop);
-  }
-
-  settings->imapaint.flag |= IMAGEPAINT_DRAWING;
-  ED_image_undo_push_begin(op->type->name, PAINT_MODE_TEXTURE_2D);
-
-  return pop;
-}
-
-static void paint_stroke_update_step(bContext *C,
-                                     wmOperator *UNUSED(op),
-                                     struct PaintStroke *stroke,
-                                     PointerRNA *itemptr)
-{
-  PaintOperation *pop = static_cast<PaintOperation *>(paint_stroke_mode_data(stroke));
-  Scene *scene = CTX_data_scene(C);
-  ToolSettings *toolsettings = CTX_data_tool_settings(C);
-  UnifiedPaintSettings *ups = &toolsettings->unified_paint_settings;
-  Brush *brush = BKE_paint_brush(&toolsettings->imapaint.paint);
-
-  float alphafac = (brush->flag & BRUSH_ACCUMULATE) ? ups->overlap_factor : 1.0f;
-
-  /* initial brush values. Maybe it should be considered moving these to stroke system */
-  float startalpha = BKE_brush_alpha_get(scene, brush);
-
-  float mouse[2];
-  float pressure;
-  float size;
-  float distance = paint_stroke_distance_get(stroke);
-  int eraser;
-
-  RNA_float_get_array(itemptr, "mouse", mouse);
-  pressure = RNA_float_get(itemptr, "pressure");
-  eraser = RNA_boolean_get(itemptr, "pen_flip");
-  size = RNA_float_get(itemptr, "size");
-
-  /* stroking with fill tool only acts on stroke end */
-  if (brush->imagepaint_tool == PAINT_TOOL_FILL) {
-    copy_v2_v2(pop->prevmouse, mouse);
-    return;
-  }
-
-  if (BKE_brush_use_alpha_pressure(brush)) {
-    BKE_brush_alpha_set(scene, brush, max_ff(0.0f, startalpha * pressure * alphafac));
-  }
-  else {
-    BKE_brush_alpha_set(scene, brush, max_ff(0.0f, startalpha * alphafac));
-  }
-
-  if ((brush->flag & BRUSH_DRAG_DOT) || (brush->flag & BRUSH_ANCHORED)) {
-    UndoStack *ustack = CTX_wm_manager(C)->undo_stack;
-    ED_image_undo_restore(ustack->step_init);
-  }
-
-  switch (pop->mode) {
-    case eTexPaintMode::_2D:
-      paint_2d_stroke(pop->stroke_handle, pop->prevmouse, mouse, eraser, pressure, distance, size);
-      break;
-
-    case eTexPaintMode::_3D_PROJECT:
-      paint_proj_stroke(
-          C, pop->stroke_handle, pop->prevmouse, mouse, eraser, pressure, distance, size);
-      break;
-  }
-
-  copy_v2_v2(pop->prevmouse, mouse);
-
-  /* restore brush values */
-  BKE_brush_alpha_set(scene, brush, startalpha);
-}
-
-static void paint_stroke_redraw(const bContext *C, struct PaintStroke *stroke, bool final)
-{
-  PaintOperation *pop = static_cast<PaintOperation *>(paint_stroke_mode_data(stroke));
-
-  switch (pop->mode) {
-    case eTexPaintMode::_2D:
-      paint_2d_redraw(C, pop->stroke_handle, final);
-      break;
-
-    case eTexPaintMode::_3D_PROJECT:
-      paint_proj_redraw(C, pop->stroke_handle, final);
-      break;
-  }
-}
-
-static void paint_stroke_done(const bContext *C, struct PaintStroke *stroke)
-{
-  Scene *scene = CTX_data_scene(C);
-  ToolSettings *toolsettings = scene->toolsettings;
-  PaintOperation *pop = static_cast<PaintOperation *>(paint_stroke_mode_data(stroke));
-  Brush *brush = BKE_paint_brush(&toolsettings->imapaint.paint);
-
-  toolsettings->imapaint.flag &= ~IMAGEPAINT_DRAWING;
-
-  if (brush->imagepaint_tool == PAINT_TOOL_FILL) {
-    if (brush->flag & BRUSH_USE_GRADIENT) {
-      switch (pop->mode) {
-        case eTexPaintMode::_2D:
-          paint_2d_gradient_fill(C, brush, pop->startmouse, pop->prevmouse, pop->stroke_handle);
-          break;
-
-        case eTexPaintMode::_3D_PROJECT:
-          paint_proj_stroke(C,
-                            pop->stroke_handle,
-                            pop->startmouse,
-                            pop->prevmouse,
-                            paint_stroke_flipped(stroke),
-                            1.0,
-                            0.0,
-                            BKE_brush_size_get(scene, brush));
-          /* two redraws, one for GPU update, one for notification */
-          paint_proj_redraw(C, pop->stroke_handle, false);
-          paint_proj_redraw(C, pop->stroke_handle, true);
-          break;
-      }
-    }
-    else {
-      switch (pop->mode) {
-        case eTexPaintMode::_2D: {
-          float color[3];
-          if (paint_stroke_inverted(stroke)) {
-            srgb_to_linearrgb_v3_v3(color, BKE_brush_secondary_color_get(scene, brush));
-          }
-          else {
-            srgb_to_linearrgb_v3_v3(color, BKE_brush_color_get(scene, brush));
-          }
-          paint_2d_bucket_fill(
-              C, color, brush, pop->startmouse, pop->prevmouse, pop->stroke_handle);
-          break;
-        }
-
-        case eTexPaintMode::_3D_PROJECT:
-          paint_proj_stroke(C,
-                            pop->stroke_handle,
-                            pop->startmouse,
-                            pop->prevmouse,
-                            paint_stroke_flipped(stroke),
-                            1.0,
-                            0.0,
-                            BKE_brush_size_get(scene, brush));
-          /* two redraws, one for GPU update, one for notification */
-          paint_proj_redraw(C, pop->stroke_handle, false);
-          paint_proj_redraw(C, pop->stroke_handle, true);
-          break;
-      }
-    }
-  }
-
-  switch (pop->mode) {
-    case eTexPaintMode::_2D:
-      paint_2d_stroke_done(pop->stroke_handle);
-      break;
-
-    case eTexPaintMode::_3D_PROJECT:
-      paint_proj_stroke_done(pop->stroke_handle);
-      break;
-  }
-
-  if (pop->cursor) {
-    WM_paint_cursor_end(pop->cursor);
-  }
-
-  ED_image_undo_push_end();
-
-  /* duplicate warning, see texpaint_init */
-#if 0
-  if (pop->s.warnmultifile) {
-    BKE_reportf(op->reports,
-                RPT_WARNING,
-                "Image requires 4 color channels to paint: %s",
-                pop->s.warnmultifile);
-  }
-  if (pop->s.warnpackedfile) {
-    BKE_reportf(op->reports,
-                RPT_WARNING,
-                "Packed MultiLayer files cannot be painted: %s",
-                pop->s.warnpackedfile);
-  }
-#endif
-  MEM_delete(pop);
-}
-
-static bool paint_stroke_test_start(bContext *C, wmOperator *op, const float mouse[2])
-{
-  PaintOperation *pop;
-
-  /* TODO: Should avoid putting this here. Instead, last position should be requested
-   * from stroke system. */
-
-  if (!(pop = texture_paint_init(C, op, mouse))) {
-    return false;
-  }
-
-  paint_stroke_set_mode_data(static_cast<PaintStroke *>(op->customdata), pop);
-
-  return true;
-}
-
-static int paint_invoke(bContext *C, wmOperator *op, const wmEvent *event)
-{
-  int retval;
-
-  op->customdata = paint_stroke_new(C,
-                                    op,
-                                    nullptr,
-                                    paint_stroke_test_start,
-                                    paint_stroke_update_step,
-                                    paint_stroke_redraw,
-                                    paint_stroke_done,
-                                    event->type);
-
-  if ((retval = op->type->modal(C, op, event)) == OPERATOR_FINISHED) {
-    paint_stroke_free(C, op, static_cast<PaintStroke *>(op->customdata));
-    return OPERATOR_FINISHED;
-  }
-  /* add modal handler */
-  WM_event_add_modal_handler(C, op);
-
-  OPERATOR_RETVAL_CHECK(retval);
-  BLI_assert(retval == OPERATOR_RUNNING_MODAL);
-
-  return OPERATOR_RUNNING_MODAL;
-}
-
-static int paint_exec(bContext *C, wmOperator *op)
-{
-  PropertyRNA *strokeprop;
-  PointerRNA firstpoint;
-  float mouse[2];
-
-  strokeprop = RNA_struct_find_property(op->ptr, "stroke");
-
-  if (!RNA_property_collection_lookup_int(op->ptr, strokeprop, 0, &firstpoint)) {
-    return OPERATOR_CANCELLED;
-  }
-
-  RNA_float_get_array(&firstpoint, "mouse", mouse);
-
-  op->customdata = paint_stroke_new(C,
-                                    op,
-                                    nullptr,
-                                    paint_stroke_test_start,
-                                    paint_stroke_update_step,
-                                    paint_stroke_redraw,
-                                    paint_stroke_done,
-                                    0);
-  /* frees op->customdata */
-  return paint_stroke_exec(C, op, static_cast<PaintStroke *>(op->customdata));
-}
-
-static int paint_modal(bContext *C, wmOperator *op, const wmEvent *event)
-{
-  return paint_stroke_modal(C, op, event, static_cast<PaintStroke *>(op->customdata));
-}
-
-static void paint_cancel(bContext *C, wmOperator *op)
-{
-  paint_stroke_cancel(C, op, static_cast<PaintStroke *>(op->customdata));
-}
-
-void PAINT_OT_image_paint(wmOperatorType *ot)
-{
-  /* identifiers */
-  ot->name = "Image Paint";
-  ot->idname = "PAINT_OT_image_paint";
-  ot->description = "Paint a stroke into the image";
-
-  /* api callbacks */
-  ot->invoke = paint_invoke;
-  ot->modal = paint_modal;
-  ot->exec = paint_exec;
-  ot->poll = image_paint_poll;
-  ot->cancel = paint_cancel;
-
-  /* flags */
-  ot->flag = OPTYPE_BLOCKING;
-
-  paint_stroke_operator_properties(ot);
-}
-
 bool get_imapaint_zoom(bContext *C, float *zoomx, float *zoomy)
 {
   ScrArea *area = CTX_wm_area(C);
diff --git a/source/blender/editors/sculpt_paint/paint_image_ops_paint.cc b/source/blender/editors/sculpt_paint/paint_image_ops_paint.cc
new file mode 100644
index 00000000000..05c637531be
--- /dev/null
+++ b/source/blender/editors/sculpt_paint/paint_image_ops_paint.cc
@@ -0,0 +1,422 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2001-2002 NaN Holding BV. All rights reserved. */
+
+/** \file
+ * \ingroup edsculpt
+ * \brief Functions to paint images in 2D and 3D.
+ */
+
+#include "DNA_brush_types.h"
+#include "DNA_color_types.h"
+#include "DNA_scene_types.h"
+#include "DNA_space_types.h"
+
+#include "BKE_brush.h"
+#include "BKE_context.h"
+#include "BKE_paint.h"
+#include "BKE_undo_system.h"
+
+#include "DEG_depsgraph.h"
+
+#include "ED_paint.h"
+#include "ED_view3d.h"
+
+#include "GPU_immediate.h"
+#include "GPU_state.h"
+
+#include "MEM_guardedalloc.h"
+
+#include "RNA_access.h"
+#include "RNA_define.h"
+
+#include "WM_api.h"
+#include "WM_message.h"
+#include "WM_toolsystem.h"
+#include "WM_types.h"
+
+#include "paint_intern.h"
+
+namespace blender::ed::sculpt_paint::image::ops::paint {
+
+enum class eTexPaintMode {
+  _2D,
+  _3D_PROJECT,
+};
+
+struct PaintOperation {
+  eTexPaintMode mode;
+
+  void *stroke_handle;
+
+  float prevmouse[2];
+  float startmouse[2];
+  double starttime;
+
+  wmPaintCursor *cursor;
+  ViewContext vc;
+};
+
+static void gradient_draw_line(bContext *UNUSED(C), int x, int y, void *customdata)
+{
+  PaintOperation *pop = (PaintOperation *)customdata;
+
+  if (pop) {
+    GPU_line_smooth(true);
+    GPU_blend(GPU_BLEND_ALPHA);
+
+    GPUVertFormat *format = immVertexFormat();
+    uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_I32, 2, GPU_FETCH_INT_TO_FLOAT);
+
+    ARegion *region = pop->vc.region;
+
+    immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
+
+    GPU_line_width(4.0);
+    immUniformColor4ub(0, 0, 0, 255);
+
+    immBegin(GPU_PRIM_LINES, 2);
+    immVertex2i(pos, x, y);
+    immVertex2i(
+        pos, pop->startmouse[0] + region->winrct.xmin, pop->startmouse[1] + region->winrct.ymin);
+    immEnd();
+
+    GPU_line_width(2.0);
+    immUniformColor4ub(255, 255, 255, 255);
+
+    immBegin(GPU_PRIM_LINES, 2);
+    immVertex2i(pos, x, y);
+    immVertex2i(
+        pos, pop->startmouse[0] + region->winrct.xmin, pop->startmouse[1] + region->winrct.ymin);
+    immEnd();
+
+    immUnbindProgram();
+
+    GPU_blend(GPU_BLEND_NONE);
+    GPU_line_smooth(false);
+  }
+}
+
+static PaintOperation *texture_paint_init(bContext *C, wmOperator *op, const float mouse[2])
+{
+  Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
+  Scene *scene = CTX_data_scene(C);
+  ToolSettings *settings = scene->toolsettings;
+  PaintOperation *pop = MEM_cnew<PaintOperation>("PaintOperation"); /* caller frees */
+  Brush *brush = BKE_paint_brush(&settings->imapaint.paint);
+  int mode = RNA_enum_get(op->ptr, "mode");
+  ED_view3d_viewcontext_init(C, &pop->vc, depsgraph);
+
+  copy_v2_v2(pop->prevmouse, mouse);
+  copy_v2_v2(pop->startmouse, mouse);
+
+  /* initialize from context */
+  if (CTX_wm_region_view3d(C)) {
+    ViewLayer *view_layer = CTX_data_view_layer(C);
+    Object *ob = OBACT(view_layer);
+    bool uvs, mat, tex, stencil;
+    if (!ED_paint_proj_mesh_data_check(scene, ob, &uvs, &mat, &tex, &stencil)) {
+      ED_paint_data_warning(op->reports, uvs, mat, tex, stencil);
+      MEM_delete(pop);
+      WM_event_add_notifier(C, NC_SCENE | ND_TOOLSETTINGS, nullptr);
+      return nullptr;
+    }
+    pop->mode = eTexPaintMode::_3D_PROJECT;
+    pop->stroke_handle = paint_proj_new_stroke(C, ob, mouse, mode);
+  }
+  else {
+    pop->mode = eTexPaintMode::_2D;
+    pop->stroke_handle = paint_2d_new_stroke(C, op, mode);
+  }
+
+  if (!pop->stroke_handle) {
+    MEM_delete(pop);
+    return nullptr;
+  }
+
+  if ((brush->imagepaint_tool == PAINT_TOOL_FILL) && (brush->flag & BRUSH_USE_GRADIENT)) {
+    pop->cursor = WM_paint_cursor_activate(
+        SPACE_TYPE_ANY, RGN_TYPE_ANY, image_paint_poll, gradient_draw_line, pop);
+  }
+
+  settings->imapaint.flag |= IMAGEPAINT_DRAWING;
+  ED_image_undo_push_begin(op->type->name, PAINT_MODE_TEXTURE_2D);
+
+  return pop;
+}
+
+static void paint_stroke_update_step(bContext *C,
+                                     wmOperator *UNUSED(op),
+                                     struct PaintStroke *stroke,
+                                     PointerRNA *itemptr)
+{
+  PaintOperation *pop = static_cast<PaintOperation *>(paint_stroke_mode_data(stroke));
+  Scene *scene = CTX_data_scene(C);
+  ToolSettings *toolsettings = CTX_data_tool_settings(C);
+  UnifiedPaintSettings *ups = &toolsettings->unified_paint_settings;
+  Brush *brush = BKE_paint_brush(&toolsettings->imapaint.paint);
+
+  float alphafac = (brush->flag & BRUSH_ACCUMULATE) ? ups->overlap_factor : 1.0f;
+
+  /* initial brush values. Maybe it should be considered moving these to stroke system */
+  float startalpha = BKE_brush_alpha_get(scene, brush);
+
+  float mouse[2];
+  float pressure;
+  float size;
+  float distance = paint_stroke_distance_get(stroke);
+  int eraser;
+
+  RNA_float_get_array(itemptr, "mouse", mouse);
+  pressure = RNA_float_get(itemptr, "pressure");
+  eraser = RNA_boolean_get(itemptr, "pen_flip");
+  size = RNA_float_get(itemptr, "size");
+
+  /* stroking with fill tool only acts on stroke end */
+  if (brush->imagepaint_tool == PAINT_TOOL_FILL) {
+    copy_v2_v2(pop->prevmouse, mouse);
+    return;
+  }
+
+  if (BKE_brush_use_alpha_pressure(brush)) {
+    BKE_brush_alpha_set(scene, brush, max_ff(0.0f, startalpha * pressure * alphafac));
+  }
+  else {
+    BKE_brush_alpha_set(scene, brush, max_ff(0.0f, startalpha * alphafac));
+  }
+
+  if ((brush->flag & BRUSH_DRAG_DOT) || (brush->flag & BRUSH_ANCHORED)) {
+    UndoStack *ustack = CTX_wm_manager(C)->undo_stack;
+    ED_image_undo_restore(ustack->step_init);
+  }
+
+  switch (pop->mode) {
+    case eTexPaintMode::_2D:
+      paint_2d_stroke(pop->stroke_handle, pop->prevmouse, mouse, eraser, pressure, distance, size);
+      break;
+
+    case eTexPaintMode::_3D_PROJECT:
+      paint_proj_stroke(
+          C, pop->stroke_handle, pop->prevmouse, mouse, eraser, pressure, distance, size);
+      break;
+  }
+
+  copy_v2_v2(pop->prevmouse, mouse);
+
+  /* restore brush values */
+  BKE_brush_alpha_set(scene, brush, startalpha);
+}
+
+static void paint_stroke_redraw(const bContext *C, struct PaintStroke *stroke, bool final)
+{
+  PaintOperation *pop = static_cast<PaintOperation *>(paint_stroke_mode_data(stroke));
+
+  switch (pop->mode) {
+    case eTexPaintMode::_2D:
+      paint_2d_redraw(C, pop->stroke_handle, final);
+      break;
+
+    case eTexPaintMode::_3D_PROJECT:
+      paint_proj_redraw(C, pop->stroke_handle, final);
+      break;
+  }
+}
+
+static void paint_stroke_done(const bContext *C, struct PaintStroke *stroke)
+{
+  Scene *scene = CTX_data_scene(C);
+  ToolSettings *toolsettings = scene->toolsettings;
+  PaintOperation *pop = static_cast<PaintOperation *>(paint_stroke_mode_data(stroke));
+  Brush *brush = BKE_paint_brush(&toolsettings->imapaint.paint);
+
+  toolsettings->imapaint.flag &= ~IMAGEPAINT_DRAWING;
+
+  if (brush->imagepaint_tool == PAINT_TOOL_FILL) {
+    if (brush->flag & BRUSH_USE_GRADIENT) {
+      switch (pop->mode) {
+        case eTexPaintMode::_2D:
+          paint_2d_gradient_fill(C, brush, pop->startmouse, pop->prevmouse, pop->stroke_handle);
+          break;
+
+        case eTexPaintMode::_3D_PROJECT:
+          paint_proj_stroke(C,
+                            pop->stroke_handle,
+                            pop->startmouse,
+                            pop->prevmouse,
+                            paint_stroke_flipped(stroke),
+                            1.0,
+                            0.0,
+                            BKE_brush_size_get(scene, brush));
+          /* two redraws, one for GPU update, one for notification */
+          paint_proj_redraw(C, pop->stroke_handle, false);
+          paint_proj_redraw(C, pop->stroke_handle, true);
+          break;
+      }
+    }
+    else {
+      switch (pop->mode) {
+        case eTexPaintMode::_2D: {
+          float color[3];
+          if (paint_stroke_inverted(stroke)) {
+            srgb_to_linearrgb_v3_v3(color, BKE_brush_secondary_color_get(scene, brush));
+          }
+          else {
+            srgb_to_linearrgb_v3_v3(color, BKE_brush_color_get(scene, brush));
+          }
+          paint_2d_bucket_fill(
+              C, color, brush, pop->startmouse, pop->prevmouse, pop->stroke_handle);
+          break;
+        }
+
+        case eTexPaintMode::_3D_PROJECT:
+          paint_proj_stroke(C,
+                            pop->stroke_handle,
+                            pop->startmouse,
+                            pop->prevmouse,
+                            paint_stroke_flipped(stroke),
+                            1.0,
+                            0.0,
+                            BKE_brush_size_get(scene, brush));
+          /* two redraws, one for GPU update, one for notification */
+          paint_proj_redraw(C, pop->stroke_handle, false);
+          paint_proj_redraw(C, pop->stroke_handle, true);
+          break;
+      }
+    }
+  }
+
+  switch (pop->mode) {
+    case eTexPaintMode::_2D:
+      paint_2d_stroke_done(pop->stroke_handle);
+      break;
+
+    case eTexPaintMode::_3D_PROJECT:
+      paint_proj_stroke_done(pop->stroke_handle);
+      break;
+  }
+
+  if (pop->cursor) {
+    WM_paint_cursor_end(pop->cursor);
+  }
+
+  ED_image_undo_push_end();
+
+  /* duplicate warning, see texpaint_init */
+#if 0
+  if (pop->s.warnmultifile) {
+    BKE_reportf(op->reports,
+                RPT_WARNING,
+                "Image requires 4 color channels to paint: %s",
+                pop->s.warnmultifile);
+  }
+  if (pop->s.warnpackedfile) {
+    BKE_reportf(op->reports,
+                RPT_WARNING,
+                "Packed MultiLayer files cannot be painted: %s",
+                pop->s.warnpackedfile);
+  }
+#endif
+  MEM_delete(pop);
+}
+
+static bool paint_stroke_test_start(bContext *C, wmOperator *op, const float mouse[2])
+{
+  PaintOperation *pop;
+
+  /* TODO: Should avoid putting this here. Instead, last position should be requested
+   * from stroke system. */
+
+  if (!(pop = texture_paint_init(C, op, mouse))) {
+    return false;
+  }
+
+  paint_stroke_set_mode_data(static_cast<PaintStroke *>(op->customdata), pop);
+
+  return true;
+}
+
+static int paint_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  int retval;
+
+  op->customdata = paint_stroke_new(C,
+                                    op,
+                                    nullptr,
+                                    paint_stroke_test_start,
+                                    paint_stroke_update_step,
+                                    paint_stroke_redraw,
+                                    paint_stroke_done,
+                                    event->type);
+
+  if ((retval = op->type->modal(C, op, event)) == OPERATOR_FINISHED) {
+    paint_stroke_free(C, op, static_cast<PaintStroke *>(op->customdata));
+    return OPERATOR_FINISHED;
+  }
+  /* add modal handler */
+  WM_event_add_modal_handler(C, op);
+
+  OPERATOR_RETVAL_CHECK(retval);
+  BLI_assert(retval == OPERATOR_RUNNING_MODAL);
+
+  return OPERATOR_RUNNING_MODAL;
+}
+
+static int paint_exec(bContext *C, wmOperator *op)
+{
+  PropertyRNA *strokeprop;
+  PointerRNA firstpoint;
+  float mouse[2];
+
+  strokeprop = RNA_struct_find_property(op->ptr, "stroke");
+
+  if (!RNA_property_collection_lookup_int(op->ptr, strokeprop, 0, &firstpoint)) {
+    return OPERATOR_CANCELLED;
+  }
+
+  RNA_float_get_array(&firstpoint, "mouse", mouse);
+
+  op->customdata = paint_stroke_new(C,
+                                    op,
+                                    nullptr,
+                                    paint_stroke_test_start,
+                                    paint_stroke_update_step,
+                                    paint_stroke_redraw,
+                                    paint_stroke_done,
+                                    0);
+  /* frees op->customdata */
+  return paint_stroke_exec(C, op, static_cast<PaintStroke *>(op->customdata));
+}
+
+static int paint_modal(bContext *C, wmOperator *op, const wmEvent *event)
+{
+  return paint_stroke_modal(C, op, event, static_cast<PaintStroke *>(op->customdata));
+}
+
+static void paint_cancel(bContext *C, wmOperator *op)
+{
+  paint_stroke_cancel(C, op, static_cast<PaintStroke *>(op->customdata));
+}
+}  // namespace blender::ed::sculpt_paint::image::ops::paint
+
+extern "C" {
+void PAINT_OT_image_paint(wmOperatorType *ot)
+{
+  using namespace blender::ed::sculpt_paint::image::ops::paint;
+
+  /* identifiers */
+  ot->name = "Image Paint";
+  ot->idname = "PAINT_OT_image_paint";
+  ot->description = "Paint a stroke into the image";
+
+  /* api callbacks */
+  ot->invoke = paint_invoke;
+  ot->modal = paint_modal;
+  ot->exec = paint_exec;
+  ot->poll = image_paint_poll;
+  ot->cancel = paint_cancel;
+
+  /* flags */
+  ot->flag = OPTYPE_BLOCKING;
+
+  paint_stroke_operator_properties(ot);
+}
+}
diff --git a/source/blender/editors/sculpt_paint/paint_intern.h b/source/blender/editors/sculpt_paint/paint_intern.h
index ba363f687dc..82fdf49c28e 100644
--- a/source/blender/editors/sculpt_paint/paint_intern.h
+++ b/source/blender/editors/sculpt_paint/paint_intern.h
@@ -269,6 +269,7 @@ void paint_brush_color_get(struct Scene *scene,
 bool paint_use_opacity_masking(struct Brush *brush);
 void paint_brush_init_tex(struct Brush *brush);
 void paint_brush_exit_tex(struct Brush *brush);
+bool image_paint_poll(struct bContext *C);
 
 void PAINT_OT_grab_clone(struct wmOperatorType *ot);
 void PAINT_OT_sample_color(struct wmOperatorType *ot);