Cleanup: Replace eTexPaintMode with classes.

For an upcoming prototype we would introduced a new eTexPaintMode
option. That would add more cases and if statements. This change migrate
the eTexPaintMode to 3 classes. AbstractPaintMode contains a shared interface.
ImagePaintMode for 2d painting and ProjectionPaintMode for 3d painting.

1 files changed, 530 insertions, 0 deletions

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..79701bba01c
--- /dev/null
+++ b/source/blender/editors/sculpt_paint/paint_image_ops_paint.cc
@@ -0,0 +1,530 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright 2001-2002 NaN Holding BV. All rights reserved. */
+
+/** \file
+ * \ingroup edsculpt
+ * \brief Painting operator to paint 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 {
+
+/**
+ * Interface to use the same painting operator for 3D and 2D painting. Interface removes the
+ * differences between the actual calls that are being performed.
+ */
+class AbstractPaintMode {
+ public:
+  virtual void *paint_new_stroke(
+      bContext *C, wmOperator *op, Object *ob, const float mouse[2], int mode) = 0;
+  virtual void paint_stroke(bContext *C,
+                            void *stroke_handle,
+                            float prev_mouse[2],
+                            float mouse[2],
+                            int eraser,
+                            float pressure,
+                            float distance,
+                            float size) = 0;
+
+  virtual void paint_stroke_redraw(const bContext *C, void *stroke_handle, bool final) = 0;
+  virtual void paint_stroke_done(void *stroke_handle) = 0;
+  virtual void paint_gradient_fill(const bContext *C,
+                                   const Scene *scene,
+                                   Brush *brush,
+                                   struct PaintStroke *stroke,
+                                   void *stroke_handle,
+                                   float mouse_start[2],
+                                   float mouse_end[2]) = 0;
+  virtual void paint_bucket_fill(const bContext *C,
+                                 const Scene *scene,
+                                 Brush *brush,
+                                 struct PaintStroke *stroke,
+                                 void *stroke_handle,
+                                 float mouse_start[2],
+                                 float mouse_end[2]) = 0;
+};
+
+class ImagePaintMode : public AbstractPaintMode {
+ public:
+  void *paint_new_stroke(bContext *C,
+                         wmOperator *op,
+                         Object *UNUSED(ob),
+                         const float UNUSED(mouse[2]),
+                         int mode) override
+  {
+    return paint_2d_new_stroke(C, op, mode);
+  }
+
+  void paint_stroke(bContext *UNUSED(C),
+                    void *stroke_handle,
+                    float prev_mouse[2],
+                    float mouse[2],
+                    int eraser,
+                    float pressure,
+                    float distance,
+                    float size) override
+  {
+    paint_2d_stroke(stroke_handle, prev_mouse, mouse, eraser, pressure, distance, size);
+  }
+
+  void paint_stroke_redraw(const bContext *C, void *stroke_handle, bool final) override
+  {
+    paint_2d_redraw(C, stroke_handle, final);
+  }
+
+  void paint_stroke_done(void *stroke_handle) override
+  {
+    paint_2d_stroke_done(stroke_handle);
+  }
+
+  void paint_gradient_fill(const bContext *C,
+                           const Scene *UNUSED(scene),
+                           Brush *brush,
+                           struct PaintStroke *UNUSED(stroke),
+                           void *stroke_handle,
+                           float mouse_start[2],
+                           float mouse_end[2]) override
+  {
+    paint_2d_gradient_fill(C, brush, mouse_start, mouse_end, stroke_handle);
+  }
+
+  void paint_bucket_fill(const bContext *C,
+                         const Scene *scene,
+                         Brush *brush,
+                         struct PaintStroke *stroke,
+                         void *stroke_handle,
+                         float mouse_start[2],
+                         float mouse_end[2]) override
+  {
+    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, mouse_start, mouse_end, stroke_handle);
+  }
+};
+
+class ProjectionPaintMode : public AbstractPaintMode {
+ public:
+  void *paint_new_stroke(
+      bContext *C, wmOperator *UNUSED(op), Object *ob, const float mouse[2], int mode) override
+  {
+    return paint_proj_new_stroke(C, ob, mouse, mode);
+  }
+
+  void paint_stroke(bContext *C,
+                    void *stroke_handle,
+                    float prev_mouse[2],
+                    float mouse[2],
+                    int eraser,
+                    float pressure,
+                    float distance,
+                    float size) override
+  {
+    paint_proj_stroke(C, stroke_handle, prev_mouse, mouse, eraser, pressure, distance, size);
+  };
+
+  void paint_stroke_redraw(const bContext *C, void *stroke_handle, bool final) override
+  {
+    paint_proj_redraw(C, stroke_handle, final);
+  }
+
+  void paint_stroke_done(void *stroke_handle) override
+  {
+    paint_proj_stroke_done(stroke_handle);
+  }
+
+  void paint_gradient_fill(const bContext *C,
+                           const Scene *scene,
+                           Brush *brush,
+                           struct PaintStroke *stroke,
+                           void *stroke_handle,
+                           float mouse_start[2],
+                           float mouse_end[2]) override
+  {
+    paint_fill(C, scene, brush, stroke, stroke_handle, mouse_start, mouse_end);
+  }
+
+  void paint_bucket_fill(const bContext *C,
+                         const Scene *scene,
+                         Brush *brush,
+                         struct PaintStroke *stroke,
+                         void *stroke_handle,
+                         float mouse_start[2],
+                         float mouse_end[2]) override
+  {
+    paint_fill(C, scene, brush, stroke, stroke_handle, mouse_start, mouse_end);
+  }
+
+ private:
+  void paint_fill(const bContext *C,
+                  const Scene *scene,
+                  Brush *brush,
+                  struct PaintStroke *stroke,
+                  void *stroke_handle,
+                  float mouse_start[2],
+                  float mouse_end[2])
+  {
+    paint_proj_stroke(C,
+                      stroke_handle,
+                      mouse_start,
+                      mouse_end,
+                      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, stroke_handle, false);
+    paint_proj_redraw(C, stroke_handle, true);
+  }
+};
+
+struct PaintOperation {
+  AbstractPaintMode *mode = nullptr;
+
+  void *stroke_handle = nullptr;
+
+  float prevmouse[2] = {0.0f, 0.0f};
+  float startmouse[2] = {0.0f, 0.0f};
+  double starttime = 0.0;
+
+  wmPaintCursor *cursor = nullptr;
+  ViewContext vc = {nullptr};
+
+  PaintOperation() = default;
+  ~PaintOperation()
+  {
+    MEM_delete(mode);
+    mode = nullptr;
+
+    if (cursor) {
+      WM_paint_cursor_end(cursor);
+      cursor = nullptr;
+    }
+  }
+};
+
+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_new<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);
+
+  ViewLayer *view_layer = CTX_data_view_layer(C);
+  Object *ob = OBACT(view_layer);
+
+  /* initialize from context */
+  if (CTX_wm_region_view3d(C)) {
+    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 = MEM_new<ProjectionPaintMode>("ProjectionPaintMode");
+  }
+  else {
+    pop->mode = MEM_new<ImagePaintMode>("ImagePaintMode");
+  }
+
+  pop->stroke_handle = pop->mode->paint_new_stroke(C, op, ob, mouse, 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);
+  }
+
+  pop->mode->paint_stroke(
+      C, pop->stroke_handle, pop->prevmouse, mouse, eraser, pressure, distance, size);
+
+  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));
+  pop->mode->paint_stroke_redraw(C, pop->stroke_handle, final);
+}
+
+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) {
+      pop->mode->paint_gradient_fill(
+          C, scene, brush, stroke, pop->stroke_handle, pop->startmouse, pop->prevmouse);
+    }
+    else {
+      pop->mode->paint_bucket_fill(
+          C, scene, brush, stroke, pop->stroke_handle, pop->startmouse, pop->prevmouse);
+    }
+  }
+  pop->mode->paint_stroke_done(pop->stroke_handle);
+  pop->stroke_handle = nullptr;
+
+  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);
+}
+}