masks.h

Go to the documentation of this file.

/*
    This file is part of darktable,
    Copyright (C) 2013-2014, 2016, 2019, 2021 Aldric Renaudin.
    Copyright (C) 2013, 2018, 2020-2021 Pascal Obry.
    Copyright (C) 2013 Simon Spannagel.
    Copyright (C) 2013-2014, 2016-2018 Tobias Ellinghaus.
    Copyright (C) 2013-2017, 2019-2020 Ulrich Pegelow.
    Copyright (C) 2014-2016 Roman Lebedev.
    Copyright (C) 2017-2019 Edgardo Hoszowski.
    Copyright (C) 2021 Hanno Schwalm.
    Copyright (C) 2021 Hubert Kowalski.
    Copyright (C) 2021 luzpaz.
    Copyright (C) 2021 Philipp Lutz.
    Copyright (C) 2021 Ralf Brown.
    Copyright (C) 2022 Martin Bařinka.
    Copyright (C) 2023, 2025-2026 Aurélien PIERRE.
    Copyright (C) 2023 Luca Zulberti.
    Copyright (C) 2025 Alynx Zhou.
    Copyright (C) 2025-2026 Guillaume Stutin.
    
    darktable 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 3 of the License, or
    (at your option) any later version.
    
    darktable 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 darktable.  If not, see <http://www.gnu.org/licenses/>.
*/
 
 
/*
Typical forms tree structure :
 
GList darktable.develop->forms
  |
  0) dt_masks_form_t  circle --------------------> ID 1771813676,  "circle #2"
  |    { GList *points
  |        | dt_masks_form_t  --------------------> dt_masks_type_t type; const dt_masks_functions_t *functions;
  |            |                                     float source[2]; char name[128]; int formid; int version;
  |              { GList *points;
  |                  | dt_masks_node_circle_t ----> float center[2]; float radius; float border;
  |
  |
  1) dt_masks_form_t  group ---------------------> ID 1771813678,  "grp retouch"
  |    { GList *points
  |        |-> dt_masks_form_group_t :   ID 1771813676,  parentid: 1771813678,    state: use show union 
  |        |-> dt_masks_form_group_t :   ID 1771942330,  parentid: 1771813678,    state: use show union 
  |
  |
  2) dt_masks_form_t  polygon -------------------> ID 1771815454,  "polygon #1"
  |    { GList *points
  |        | dt_masks_form_t   -------------------> dt_masks_type_t type; const dt_masks_functions_t *functions;
  |              |                                   float source[2]; char name[128]; int formid; int version;
  |              { GList *points;
  |                  | dt_masks_node_polygon_t ---> float node[2]; float ctrl1[2]; float ctrl2[2]; float border[2];
  |                  | dt_masks_node_polygon_t ---> ...
  |                  | ...
  |                  | ...
  |
  |
  3) dt_masks_form_t  group ---------------------> ID 1771942331,  "grp exposure"
  |    { GList *points
  |        |-> dt_masks_form_group_t :  ID 1771815454,   parentid: 1771942331,    state: use show union 
  |        |-> dt_masks_form_group_t :  ID 1771877226,   parentid: 1771942331,    state: use show union 
  |        |-> dt_masks_form_group_t :  ID 1771877232,   parentid: 1771942331,    state: use show union 
  |
  |
  4) dt_masks_form_t  ellipse -------------------> ID 1771877226,  "ellipse #1"
  |    { GList *points
  |        | dt_masks_form_t  --------------------> dt_masks_type_t type; const dt_masks_functions_t *functions;
  |              |                                   float source[2]; char name[128]; int formid; int version;
  |              { GList *points;
  |                  | dt_masks_node_ellipse_t ---> float center[2]; float radius[2]; float rotation;
  |                                                  float border; dt_masks_ellipse_flags_t flags;
  |
  |
  5) dt_masks_form_t  brush ---------------------> ID 1771877232,  "brush #1"
  |    { GList *points
  |        | dt_masks_form_t  --------------------> dt_masks_type_t type; const dt_masks_functions_t *functions;
  |              |                                   float source[2]; char name[128]; int formid; int version;
  |              { GList *points;
  |                  | dt_masks_node_brush_t ----->  float node[2]; float pressure; float hardness; float size;
  |                  |                                dt_masks_pressure_sensitivity_t pressure_sensitivity;
  |                  | dt_masks_node_brush_t -----> ...
  |                  |
  |                  | ...
  |                  | ...
  |
  |
  6) dt_masks_form_t  gradient -------------------> ID 1771942330,  "gradient #1"
  |    { GList *points
  |        | dt_masks_form_t  ---------------------> dt_masks_type_t type; const dt_masks_functions_t *functions;
  |              |                                    float source[2]; char name[128]; int formid; int version;
  |              { GList *points;
  |                  | dt_masks_anchor_gradient_t -> float center[2]; float rotation; float extent; float steepness; float curvature;
  |
  7)...
  |
  ...
 
 
*/
 
#pragma once
 
#include "common/darktable.h"
#include "common/opencl.h"
#include "develop/pixelpipe.h"
#include "dtgtk/button.h"
#include "dtgtk/gradientslider.h"
#include "gui/draw.h"
#include "control/control.h"
 
#include <assert.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
#define DEVELOP_MASKS_VERSION (6)
 
typedef enum dt_masks_type_t
{
  DT_MASKS_NONE = 0, // keep first
  DT_MASKS_CIRCLE = 1 << 0,
  DT_MASKS_POLYGON = 1 << 1,
  DT_MASKS_GROUP = 1 << 2,
  DT_MASKS_CLONE = 1 << 3,
  DT_MASKS_GRADIENT = 1 << 4,
  DT_MASKS_ELLIPSE = 1 << 5,
  DT_MASKS_BRUSH = 1 << 6,
  DT_MASKS_NON_CLONE = 1 << 7,
 
  DT_MASKS_ALL = DT_MASKS_CIRCLE | DT_MASKS_POLYGON | DT_MASKS_GROUP |
                 DT_MASKS_GRADIENT | DT_MASKS_ELLIPSE | DT_MASKS_BRUSH,
 
  DT_MASKS_IS_CLOSED_SHAPE = DT_MASKS_CIRCLE | DT_MASKS_ELLIPSE | DT_MASKS_POLYGON,
  DT_MASKS_IS_OPEN_SHAPE   = DT_MASKS_ALL & ~DT_MASKS_IS_CLOSED_SHAPE,
  
  DT_MASKS_IS_RETOUCHE = DT_MASKS_CLONE | DT_MASKS_NON_CLONE,
 
  DT_MASKS_IS_PATH_SHAPE   = DT_MASKS_POLYGON | DT_MASKS_BRUSH,
  DT_MASKS_IS_PRIMITIVE_SHAPE = DT_MASKS_CIRCLE | DT_MASKS_ELLIPSE | DT_MASKS_GRADIENT
 
} dt_masks_type_t;
 
typedef enum dt_masks_event_t
{
  DT_MASKS_EVENT_NONE   = 0,
  DT_MASKS_EVENT_ADD    = 1,
  DT_MASKS_EVENT_REMOVE = 2,
  DT_MASKS_EVENT_UPDATE = 3,
  DT_MASKS_EVENT_DELETE = 4,
  DT_MASKS_EVENT_CHANGE = 5,
  DT_MASKS_EVENT_RESET  = 6
} dt_masks_event_t;
typedef enum dt_masks_state_t
{
  DT_MASKS_STATE_NONE = 0,
  DT_MASKS_STATE_USE = 1 << 0,
  DT_MASKS_STATE_SHOW = 1 << 1,
  DT_MASKS_STATE_INVERSE = 1 << 2,
  DT_MASKS_STATE_UNION = 1 << 3,
  DT_MASKS_STATE_INTERSECTION = 1 << 4,
  DT_MASKS_STATE_DIFFERENCE = 1 << 5,
  DT_MASKS_STATE_EXCLUSION = 1 << 6,
  DT_MASKS_STATE_NOOP = 1 << 7,
 
  DT_MASKS_STATE_IS_COMBINE_OP = DT_MASKS_STATE_UNION | DT_MASKS_STATE_INTERSECTION | DT_MASKS_STATE_DIFFERENCE | DT_MASKS_STATE_EXCLUSION
} dt_masks_state_t;
 
typedef enum dt_masks_points_states_t
{
  DT_MASKS_POINT_STATE_NORMAL = 1,
  DT_MASKS_POINT_STATE_USER = 2
} dt_masks_points_states_t;
 
typedef enum dt_masks_gradient_states_t
{
  DT_MASKS_GRADIENT_STATE_LINEAR = 1,
  DT_MASKS_GRADIENT_STATE_SIGMOIDAL = 2
} dt_masks_gradient_states_t;
 
typedef enum dt_masks_increment_t
{
  DT_MASKS_INCREMENT_ABSOLUTE = 0,
  DT_MASKS_INCREMENT_SCALE = 1,
  DT_MASKS_INCREMENT_OFFSET = 2
} dt_masks_increment_t;
 
typedef enum dt_masks_edit_mode_t
{
  DT_MASKS_EDIT_OFF = 0,
  DT_MASKS_EDIT_FULL = 1,
  DT_MASKS_EDIT_RESTRICTED = 2
} dt_masks_edit_mode_t;
 
typedef enum dt_masks_pressure_sensitivity_t
{
  DT_MASKS_PRESSURE_OFF = 0,
  DT_MASKS_PRESSURE_HARDNESS_REL = 1,
  DT_MASKS_PRESSURE_HARDNESS_ABS = 2,
  DT_MASKS_PRESSURE_OPACITY_REL = 3,
  DT_MASKS_PRESSURE_OPACITY_ABS = 4,
  DT_MASKS_PRESSURE_BRUSHSIZE_REL = 5
} dt_masks_pressure_sensitivity_t;
 
typedef enum dt_masks_ellipse_flags_t
{
  DT_MASKS_ELLIPSE_EQUIDISTANT = 0,
  DT_MASKS_ELLIPSE_PROPORTIONAL = 1
} dt_masks_ellipse_flags_t;
 
typedef enum dt_masks_source_pos_type_t
{
  DT_MASKS_SOURCE_POS_RELATIVE = 0,
  DT_MASKS_SOURCE_POS_RELATIVE_TEMP = 1,
  DT_MASKS_SOURCE_POS_ABSOLUTE = 2
} dt_masks_source_pos_type_t;
 
typedef struct dt_masks_node_circle_t
{
  float center[2]; // point in normalized input space
  float radius;
  float border;
} dt_masks_node_circle_t;
 
typedef struct dt_masks_node_ellipse_t
{
  float center[2];
  float radius[2];
  float rotation;
  float border;
  dt_masks_ellipse_flags_t flags;
} dt_masks_node_ellipse_t;
 
typedef struct dt_masks_node_polygon_t
{
  float node[2];
  float ctrl1[2];
  float ctrl2[2];
  float border[2];
  dt_masks_points_states_t state;
} dt_masks_node_polygon_t;
 
typedef struct dt_masks_node_brush_t
{
  float node[2];
  float ctrl1[2];
  float ctrl2[2];
  float border[2];
  float density;
  float hardness;
  dt_masks_points_states_t state;
} dt_masks_node_brush_t;
 
typedef struct dt_masks_anchor_gradient_t
{
  float center[2];
  float rotation;
  float extent;
  float steepness;
  float curvature;
  dt_masks_gradient_states_t state;
} dt_masks_anchor_gradient_t;
 
typedef struct dt_masks_form_group_t
{
  int formid;
  int parentid;
  int state;
  float opacity;
} dt_masks_form_group_t;
 
struct dt_masks_form_t;
struct dt_masks_form_gui_t;
struct dt_develop_t;
 
/*
* Type of user interaction to map with internal properties of masks.
* Those were initially handled implicitly by Shift/Ctrl/Shift+Ctrl + mouse scroll
* at the scope of each mask type, which is a shitty design when using Wacom tablets.
* This case is now covered by the DT_MASK_INTERACTION_UNDEF.
* Otherwise, when calling the mouse_scroll callback from GUI, we set the case
* explicitly, along with a value.
*/
typedef enum dt_masks_interaction_t
{
  DT_MASKS_INTERACTION_UNDEF = 0,    // let it be deduced contextually from key modifiers, implicit
  DT_MASKS_INTERACTION_SIZE = 1,     // property of the form (shape), explicit
  DT_MASKS_INTERACTION_HARDNESS = 2, // property of the form (shape), explicit
  DT_MASKS_INTERACTION_OPACITY = 3,  // property of the group in which the form is included, explicit
  DT_MASKS_INTERACTION_LAST
} dt_masks_interaction_t;
 
typedef struct dt_masks_functions_t
{
  int point_struct_size;   // sizeof(struct dt_masks_point_*_t)
  void (*sanitize_config)(dt_masks_type_t type_flags);
  void (*set_form_name)(struct dt_masks_form_t *const form, const size_t nb);
  void (*set_hint_message)(const struct dt_masks_form_gui_t *const gui, const struct dt_masks_form_t *const form,
                           const int opacity, char *const __restrict__ msgbuf, const size_t msgbuf_len);
  void (*duplicate_points)(struct dt_develop_t *const dev, struct dt_masks_form_t *base, struct dt_masks_form_t *dest);
  void (*initial_source_pos)(const float iwd, const float iht, float *x, float *y);
  // input coordinates are in absolute output-image space, dist is squared in the same space
  void (*get_distance)(float x, float y, float as, struct dt_masks_form_gui_t *gui, int index, int num_points,
                       int *inside, int *inside_border, int *near, int *inside_source, float *dist);
  int (*get_points)(struct dt_develop_t *dev, float x, float y, float radius_a, float radius_b, float rotation,
                    float **points, int *points_count);
  int (*get_points_border)(struct dt_develop_t *dev, struct dt_masks_form_t *form, float **points, int *points_count,
                           float **border, int *border_count, int source, const dt_iop_module_t *const module);
  int (*get_mask)(const dt_iop_module_t *const module, struct dt_dev_pixelpipe_t *pipe,
                  const dt_dev_pixelpipe_iop_t *const piece,
                  struct dt_masks_form_t *const form,
                  float **buffer, int *width, int *height, int *posx, int *posy);
  int (*get_mask_roi)(const dt_iop_module_t *const fmodule, struct dt_dev_pixelpipe_t *pipe,
                      const dt_dev_pixelpipe_iop_t *const piece,
                      struct dt_masks_form_t *const form,
                      const dt_iop_roi_t *roi, float *buffer);
  int (*get_area)(const dt_iop_module_t *const module, struct dt_dev_pixelpipe_t *pipe,
                  const dt_dev_pixelpipe_iop_t *const piece,
                  struct dt_masks_form_t *const form,
                  int *width, int *height, int *posx, int *posy);
  int (*get_source_area)(dt_iop_module_t *module, struct dt_dev_pixelpipe_t *pipe,
                         dt_dev_pixelpipe_iop_t *piece, struct dt_masks_form_t *form,
                         int *width, int *height, int *posx, int *posy);
  gboolean (*get_gravity_center)(const struct dt_masks_form_t *form, float center[2], float *area);
  float (*get_interaction_value)(const struct dt_masks_form_t *form, dt_masks_interaction_t interaction);
  float (*set_interaction_value)(struct dt_masks_form_t *form, dt_masks_interaction_t interaction, float value,
                                 dt_masks_increment_t increment, int flow,
                                 struct dt_masks_form_gui_t *gui, struct dt_iop_module_t *module);
  /* Recompute hovered handles/nodes from the cached cursor state in gui. */
  int (*update_hover)(struct dt_masks_form_t *form, struct dt_masks_form_gui_t *gui, int index);
  /* Mouse x and y are widget-space coordinates from GTK/Cairo */
  int (*mouse_moved)(struct dt_iop_module_t *module, double x, double y, double pressure, int which,
                     struct dt_masks_form_t *form, int parentid, struct dt_masks_form_gui_t *gui, int index);
  /* Mouse x and y are widget-space coordinates from GTK/Cairo */
  int (*mouse_scrolled)(struct dt_iop_module_t *module, double x, double y, int up, const int delta_y, uint32_t state,
                        struct dt_masks_form_t *form, int parentid, struct dt_masks_form_gui_t *gui, int index,
                        dt_masks_interaction_t interaction);
  /* Mouse x and y are widget-space coordinates from GTK/Cairo */
  int (*button_pressed)(struct dt_iop_module_t *module, double x, double y,
                        double pressure, int which, int type, uint32_t state,
                        struct dt_masks_form_t *form, int parentid, struct dt_masks_form_gui_t *gui, int index);
  /* Mouse x and y are widget-space coordinates from GTK/Cairo */
  int (*button_released)(struct dt_iop_module_t *module, double x, double y, int which, uint32_t state,
                         struct dt_masks_form_t *form, int parentid, struct dt_masks_form_gui_t *gui, int index);
  /* Key event */
  int (*key_pressed)(struct dt_iop_module_t *module, GdkEventKey *event, struct dt_masks_form_t *form, int parentid, struct dt_masks_form_gui_t *gui, int index);
  void (*post_expose)(cairo_t *cr, float zoom_scale, struct dt_masks_form_gui_t *gui, int index, int num_points);
  // The function to draw the shape in question.
  void (*draw_shape)(cairo_t *cr, const float *points, const int points_count, const int nb, const gboolean border, const gboolean source);
  void (*init_ctrl_points)(struct dt_masks_form_t *form);
  int (*populate_context_menu)(GtkWidget *menu, struct dt_masks_form_t *form, struct dt_masks_form_gui_t *gui, const float pzx, const float pzy);
} dt_masks_functions_t;
 
typedef struct dt_masks_form_t
{
  GList *points; // list of point structures (nodes)
  dt_masks_type_t type;
  const dt_masks_functions_t *functions;
  // TRUE when gui_points->points uses the Bezier layout (points[k*6+2])
  gboolean uses_bezier_points_layout;
 
  // position of the origin point of source (used only for clone)
  // in normalized coordinates in raw input space
  float source[2];
 
  // cached center of gravity
  // in normalized coordinates in raw input space
  float gravity_center[2];
 
  // cached shape area, taken as a weight estimator to get
  // the gravity center of multi-shapes by combining
  // weight and gravity centers of all shapes
  float area;
  // name of the form
  char name[128];
  // id used to store the form
  int formid;
  // version of the form
  int version;
} dt_masks_form_t;
 
typedef struct dt_masks_form_gui_points_t
{
  float *points;   // points in absolute coordinates in output image space
  int points_count;
  float *border;   // border points in absolute coordinates in output image space
  int border_count;
  float *source;   // source point in absolute coordinates in output image space
  int source_count;
  gboolean clockwise;
} dt_masks_form_gui_points_t;
 
typedef struct dt_masks_dynbuf_t
{
  float *buffer;
  char tag[128];
  size_t pos;
  size_t size;
} dt_masks_dynbuf_t;
 
 
typedef struct dt_masks_form_gui_t
{
  dt_masks_type_t type;
  // currently visible form when editing masks (GUI-only; may be a temporary copy)
  dt_masks_form_t *form_visible;
  // points used to draw the form
  GList *points; // list of dt_masks_form_gui_points_t 
 
  // points used to sample mouse moves
  dt_masks_dynbuf_t *guipoints, *guipoints_payload;
  int guipoints_count;
 
  // values for mouse positions, etc...
 
  // Mouse position in absolute coordinates in final image space
  // This is used to map input event handlers to *_post_expose() drawing functions
  // and to record drag & drop starting coordinates.
  float pos[2];
 
  // Mouse position in normalized coordinates in output image space.
  // This is cached once per top-level event and replaces ad-hoc pzx/pzy recomputation.
  float rel_pos[2];
 
  // Mouse position in absolute coordinates in raw input image space.
  // This is cached once per top-level event so nested handlers can reuse it.
  float raw_pos[2];
 
  // delta movement of the mouse in absolute coordinates in final image space
  // This is used to map input event handlers to *_post_expose() drawing functions
  float delta[2];
 
  // scroll offset
  float scrollx, scrolly;
 
  // Position of a clone mask's source point (in what coordinates space ?)
  float pos_source[2];
 
  dt_masks_edit_mode_t edit_mode;
 
  int node_hovered;           // this is the index of the node, refreshed on mouse_moved when a a group is selected
  int handle_hovered;         // this is the index of the node, refreshed on mouse_moved when a a group is selected
  int seg_hovered;            // this is the index of the segment, refreshed on mouse_moved when a a group is selected
  int handle_border_hovered;  // this is the index of the node, refreshed on mouse_moved when a a group is selected
 
  gboolean node_selected;     // this is the state of the node referenced by node_hovered
  gboolean handle_selected;   // this is the state of the handle referenced by handle_hovered
  gboolean seg_selected;      // this is the state of the segment referenced by segment_hovered
  gboolean handle_border_selected; // this is the state of the border handle referenced by handle_border_hovered
  int node_selected_idx;      // stable selected node index, distinct from current hover
 
  gboolean form_selected;
  gboolean border_selected;
  gboolean source_selected;
  gboolean pivot_selected;
 
  int group_selected;
  
  int source_pos_type;
 
  gboolean form_dragging;
  gboolean source_dragging;
  gboolean form_rotating;
  gboolean border_toggling;
  gboolean gradient_toggling;
  int node_dragging;
  int handle_dragging;
  int seg_dragging;
  int handle_border_dragging;
 
  // Throttle GUI rebuilds while dragging to avoid heavy border recomputation.
  double last_rebuild_ts;
  float last_rebuild_pos[2];
  gboolean rebuild_pending;
 
  // Throttle handle hit-testing when cursor barely moves.
  float last_hit_test_pos[2];
 
  gboolean creation;
  gboolean creation_closing_form;
  dt_iop_module_t *creation_module;
 
  dt_masks_pressure_sensitivity_t pressure_sensitivity;
 
  // ids
  int formid;
  uint64_t pipe_hash;
} dt_masks_form_gui_t;
 
dt_masks_form_t *dt_masks_get_visible_form(const struct dt_develop_t *dev);
void dt_masks_set_visible_form(struct dt_develop_t *dev, dt_masks_form_t *form);
void dt_masks_gui_init(struct dt_develop_t *dev);
void dt_masks_gui_cleanup(struct dt_develop_t *dev);
void dt_masks_gui_set_dragging(dt_masks_form_gui_t *gui);
void dt_masks_gui_reset_dragging(dt_masks_form_gui_t *gui);
gboolean dt_masks_gui_is_dragging(const dt_masks_form_gui_t *gui);
 
// Test wether the form, the border, the source or the pivot is selected 
static inline gboolean dt_masks_gui_was_anything_selected(const dt_masks_form_gui_t *gui)
{
  return gui && (gui->form_selected || gui->border_selected || gui->source_selected || gui->pivot_selected);
}
 
static inline int dt_masks_gui_selected_node_index(const dt_masks_form_gui_t *gui)
{
  return (gui && gui->node_selected) ? gui->node_selected_idx : -1;
}
 
static inline int dt_masks_gui_selected_handle_index(const dt_masks_form_gui_t *gui)
{
  return (gui && gui->handle_selected) ? gui->handle_hovered : -1;
}
 
static inline int dt_masks_gui_selected_handle_border_index(const dt_masks_form_gui_t *gui)
{
  return (gui && gui->handle_border_selected) ? gui->handle_border_hovered : -1;
}
 
static inline int dt_masks_gui_selected_segment_index(const dt_masks_form_gui_t *gui)
{
  return (gui) ? gui->seg_hovered : -1;
}
 
static inline gboolean dt_masks_gui_change_affects_selected_node_or_all(const dt_masks_form_gui_t *gui,
                                                                        const int index)
{
  if(!gui) return TRUE;
 
  const int selected_node = dt_masks_gui_selected_node_index(gui);
  return selected_node < 0 || selected_node == index;
}
 
static inline float dt_masks_get_form_size_from_nodes(const GList *points)
{
  if(!points || !points->data) return 0.0f;
 
  // Brush and polygon node payloads both start with `float node[2]`.
  const float *first = (const float *)points->data;
  float min_x = first[0];
  float max_x = first[0];
  float min_y = first[1];
  float max_y = first[1];
 
  for(const GList *point_node = points; point_node; point_node = g_list_next(point_node))
  {
    const float *node = (const float *)point_node->data;
    if(!node) continue;
    min_x = fminf(min_x, node[0]);
    max_x = fmaxf(max_x, node[0]);
    min_y = fminf(min_y, node[1]);
    max_y = fmaxf(max_y, node[1]);
  }
 
  return fmaxf(max_x - min_x, max_y - min_y);
}
 
static inline gboolean dt_masks_gui_should_hit_test(dt_masks_form_gui_t *gui)
{
  const float hit_thresh = DT_GUI_MOUSE_EFFECT_RADIUS_SCALED * 0.5f;
  const float dx = gui->pos[0] - gui->last_hit_test_pos[0];
  const float dy = gui->pos[1] - gui->last_hit_test_pos[1];
  if(gui->last_hit_test_pos[0] < 0.0f || (dx * dx + dy * dy) > (hit_thresh * hit_thresh))
  {
    gui->last_hit_test_pos[0] = gui->pos[0];
    gui->last_hit_test_pos[1] = gui->pos[1];
    return TRUE;
  }
  return FALSE;
}
 
// High-level mask event dispatchers cache the current cursor in raw absolute coordinates.
// Reuse that cache for current-cursor conversions instead of backtransforming `gui->pos` again.
static inline void dt_masks_gui_cursor_to_raw_norm(dt_develop_t *dev, const dt_masks_form_gui_t *gui, float point[2])
{
  point[0] = gui->raw_pos[0];
  point[1] = gui->raw_pos[1];
  dt_dev_coordinates_raw_abs_to_raw_norm(dev, point, 1);
}
 
// Reuse the cached absolute output-image cursor and drag delta to derive a raw-normalized point.
static inline void dt_masks_gui_delta_to_raw_norm(dt_develop_t *dev, const dt_masks_form_gui_t *gui, float point[2])
{
  point[0] = gui->pos[0] + gui->delta[0];
  point[1] = gui->pos[1] + gui->delta[1];
  dt_dev_coordinates_image_abs_to_raw_norm(dev, point, 1);
}
 
static inline void dt_masks_gui_delta_to_image_abs(const dt_masks_form_gui_t *gui, float point[2])
{
  point[0] = gui->pos[0] + gui->delta[0];
  point[1] = gui->pos[1] + gui->delta[1];
}
 
// Drag branches need the same "cursor + drag delta" converted back to raw space.
// Keep that conversion in one place so all shapes use the same anchor semantics.
static inline void dt_masks_gui_delta_from_raw_anchor(dt_develop_t *dev, const dt_masks_form_gui_t *gui,
                                                      const float anchor[2], float *delta_x, float *delta_y)
{
  float point[2];
  dt_masks_gui_delta_to_raw_norm(dev, gui, point);
  *delta_x = point[0] - anchor[0];
  *delta_y = point[1] - anchor[1];
}
 
// Clone and spot forms share the same default presets, while regular drawn masks use their own.
static inline gboolean dt_masks_form_uses_spot_defaults(const dt_masks_form_t *form)
{
  return (form->type & (DT_MASKS_CLONE | DT_MASKS_NON_CLONE)) != 0;
}
 
static inline gboolean dt_masks_form_is_clone(const dt_masks_form_t *form)
{
  return (form->type & DT_MASKS_CLONE) != 0;
}
 
static inline void dt_masks_reset_source(dt_masks_form_t *form)
{
  form->source[0] = 0.0f;
  form->source[1] = 0.0f;
}
 
static inline void dt_masks_translate_source(dt_masks_form_t *form, const float delta_x, const float delta_y)
{
  form->source[0] += delta_x;
  form->source[1] += delta_y;
}
 
static inline void dt_masks_translate_ctrl_node(float node[2], float ctrl1[2], float ctrl2[2],
                                                const float delta_x, const float delta_y)
{
  node[0] += delta_x;
  node[1] += delta_y;
  ctrl1[0] += delta_x;
  ctrl1[1] += delta_y;
  ctrl2[0] += delta_x;
  ctrl2[1] += delta_y;
}
 
static inline void dt_masks_set_ctrl_points(float ctrl1[2], float ctrl2[2], const float control_points[4])
{
  ctrl1[0] = control_points[0];
  ctrl1[1] = control_points[1];
  ctrl2[0] = control_points[2];
  ctrl2[1] = control_points[3];
}
 
gboolean dt_masks_node_is_cusp(const dt_masks_form_gui_points_t *gpt, const int index);
void dt_masks_gui_form_create(dt_masks_form_t *form, dt_masks_form_gui_t *gui, int index,
                              struct dt_iop_module_t *module);
 
// Brush and polygon nodes share the same node/control-point edit semantics.
static inline gboolean dt_masks_toggle_bezier_node_type(struct dt_iop_module_t *module,
                                                        struct dt_masks_form_t *mask_form,
                                                        struct dt_masks_form_gui_t *mask_gui,
                                                        const int form_index,
                                                        const struct dt_masks_form_gui_points_t *gui_points,
                                                        const int node_index,
                                                        float node[2], float ctrl1[2], float ctrl2[2],
                                                        dt_masks_points_states_t *state)
{
  if(!mask_form || !mask_gui || !gui_points || !state || node_index < 0) return FALSE;
 
  if(dt_masks_node_is_cusp(gui_points, node_index))
  {
    *state = DT_MASKS_POINT_STATE_NORMAL;
    if(mask_form->functions && mask_form->functions->init_ctrl_points)
      mask_form->functions->init_ctrl_points(mask_form);
  }
  else
  {
    ctrl1[0] = ctrl2[0] = node[0];
    ctrl1[1] = ctrl2[1] = node[1];
    *state = DT_MASKS_POINT_STATE_USER;
  }
 
  dt_masks_gui_form_create(mask_form, mask_gui, form_index, module);
  return TRUE;
}
 
static inline gboolean dt_masks_reset_bezier_ctrl_points(struct dt_iop_module_t *module,
                                                         struct dt_masks_form_t *mask_form,
                                                         struct dt_masks_form_gui_t *mask_gui,
                                                         const int form_index,
                                                         const struct dt_masks_form_gui_points_t *gui_points,
                                                         const int node_index,
                                                         dt_masks_points_states_t *state)
{
  if(!mask_form || !mask_gui || !gui_points || !state || node_index < 0) return FALSE;
 
  if(*state != DT_MASKS_POINT_STATE_NORMAL && !dt_masks_node_is_cusp(gui_points, node_index))
  {
    *state = DT_MASKS_POINT_STATE_NORMAL;
    if(mask_form->functions && mask_form->functions->init_ctrl_points)
      mask_form->functions->init_ctrl_points(mask_form);
    dt_masks_gui_form_create(mask_form, mask_gui, form_index, module);
  }
 
  return TRUE;
}
 
// Brush and polygon border handles both constrain the cursor to the node->handle axis.
static inline void dt_masks_project_on_line(const float cursor[2], const float node[2],
                                            const float handle[2], float point[2])
{
  const float dx_line = handle[0] - node[0];
  const float dy_line = handle[1] - node[1];
 
  if(fabsf(dx_line) < 1e-6f)
  {
    point[0] = node[0];
    point[1] = cursor[1];
  }
  else
  {
    const float a = dy_line / dx_line;
    const float b = node[1] - a * node[0];
    const float denom = a * a + 1.0f;
    const float xproj = (a * cursor[1] + cursor[0] - b * a) / denom;
 
    point[0] = xproj;
    point[1] = a * xproj + b;
  }
}
 
// Border handles store normalized raw-space radii, but hit/drag code works in image space.
// Convert both ends once here so all shapes derive border thickness the same way.
static inline float dt_masks_border_from_projected_handle(dt_develop_t *dev, const float node[2],
                                                          const float projected_image_pos[2],
                                                          const float scale_ref)
{
  float projected_raw[2] = { projected_image_pos[0], projected_image_pos[1] };
  float node_raw[2] = { node[0], node[1] };
  dt_dev_coordinates_image_abs_to_raw_abs(dev, projected_raw, 1);
  dt_dev_coordinates_raw_norm_to_raw_abs(dev, node_raw, 1);
 
  const float delta_x = projected_raw[0] - node_raw[0];
  const float delta_y = projected_raw[1] - node_raw[1];
  return sqrtf(delta_x * delta_x + delta_y * delta_y) / scale_ref;
}
 
// Circle, ellipse and gradient creation previews all follow the same drawing sequence:
// optional save/restore, draw the shape, then draw the border preview if present.
static inline void dt_masks_draw_preview_shape(cairo_t *cr, const float zoom_scale, const int num_points,
                                               float *points, const int points_count,
                                               float *border, const int border_count,
                                               void (*const *draw_shape)(cairo_t *cr, const float *points,
                                                                         const int points_count, const int nb,
                                                                         const gboolean border,
                                                                         const gboolean source),
                                               const cairo_line_cap_t shape_cap,
                                               const cairo_line_cap_t border_cap,
                                               const gboolean save_restore)
{
  if(save_restore) cairo_save(cr);
  if(points && points_count > 0)
    dt_draw_shape_lines(DT_MASKS_NO_DASH, FALSE, cr, num_points, FALSE, zoom_scale, points, points_count,
                        draw_shape, shape_cap);
  if(border && border_count > 0)
    dt_draw_shape_lines(DT_MASKS_DASH_STICK, FALSE, cr, num_points, FALSE, zoom_scale, border, border_count,
                        draw_shape, border_cap);
  if(save_restore) cairo_restore(cr);
}
 
// Shared scratch buffers for creation previews. Keeping them grouped makes the shape
// preview helpers return a single value and centralizes cleanup.
typedef struct dt_masks_preview_buffers_t
{
  float *points;
  int points_count;
  float *border;
  int border_count;
} dt_masks_preview_buffers_t;
 
static inline void dt_masks_preview_buffers_cleanup(dt_masks_preview_buffers_t *buffers)
{
  dt_pixelpipe_cache_free_align(buffers->points);
  dt_pixelpipe_cache_free_align(buffers->border);
}
 
typedef struct dt_masks_gui_center_point_t
{
  struct
  {
    float x;
    float y;
  }main;
 
  struct 
  {
    float x;
    float y;
  }source;
} dt_masks_gui_center_point_t;
 
extern const dt_masks_functions_t dt_masks_functions_circle;
extern const dt_masks_functions_t dt_masks_functions_ellipse;
extern const dt_masks_functions_t dt_masks_functions_brush;
extern const dt_masks_functions_t dt_masks_functions_polygon;
extern const dt_masks_functions_t dt_masks_functions_gradient;
extern const dt_masks_functions_t dt_masks_functions_group;
 
void dt_masks_init_form_gui(dt_masks_form_gui_t *gui);
 
int dt_masks_get_points_border(struct dt_develop_t *dev, dt_masks_form_t *form, float **points, int *points_count,
                               float **border, int *border_count, int source, dt_iop_module_t *module);
 
int dt_masks_get_area(dt_iop_module_t *module, dt_dev_pixelpipe_t *pipe, dt_dev_pixelpipe_iop_t *piece,
                      dt_masks_form_t *form,
                      int *width, int *height, int *posx, int *posy);
int dt_masks_get_source_area(dt_iop_module_t *module, dt_dev_pixelpipe_t *pipe,
                             dt_dev_pixelpipe_iop_t *piece, dt_masks_form_t *form,
                             int *width, int *height, int *posx, int *posy);
static inline int dt_masks_get_mask(const dt_iop_module_t *const module, dt_dev_pixelpipe_t *pipe,
                      const dt_dev_pixelpipe_iop_t *const piece,
                      dt_masks_form_t *const form,
                      float **buffer, int *width, int *height, int *posx, int *posy)
{
  return (form->functions && form->functions->get_mask)
    ? form->functions->get_mask(module, pipe, piece, form, buffer, width, height, posx, posy)
    : 1;
}
static inline int dt_masks_get_mask_roi(const dt_iop_module_t *const module, dt_dev_pixelpipe_t *pipe,
                          const dt_dev_pixelpipe_iop_t *const piece,
                          dt_masks_form_t *const form, const dt_iop_roi_t *roi, float *buffer)
{
  return (form->functions && form->functions->get_mask_roi)
    ? form->functions->get_mask_roi(module, pipe, piece, form, roi, buffer)
    : 1;
}
 
int dt_masks_group_render_roi(dt_iop_module_t *module, dt_dev_pixelpipe_t *pipe,
                              const dt_dev_pixelpipe_iop_t *piece, dt_masks_form_t *form,
                              const dt_iop_roi_t *roi, float *buffer);
 
// returns current masks version
int dt_masks_version(void);
 
void dt_masks_append_form(dt_develop_t *dev, dt_masks_form_t *form);
void dt_masks_remove_form(dt_develop_t *dev, dt_masks_form_t *form);
void dt_masks_remove_node(struct dt_iop_module_t *module, dt_masks_form_t *form, int parentid,
                          dt_masks_form_gui_t *gui, int index, int node_index);
 
// update masks from older versions
int dt_masks_legacy_params(dt_develop_t *dev, void *params, const int old_version, const int new_version);
/*
 * TODO:
 *
 * int
 * dt_masks_legacy_params(
 *   dt_develop_t *dev,
 *   const void *const old_params, const int old_version,
 *   void *new_params,             const int new_version);
 */
 
dt_masks_form_t *dt_masks_create(dt_masks_type_t type);
dt_masks_form_t *dt_masks_create_ext(dt_masks_type_t type);
void dt_masks_replace_current_forms(dt_develop_t *dev, GList *forms);
GList *dt_masks_snapshot_current_forms(dt_develop_t *dev, gboolean reset_changed);
dt_masks_form_t *dt_masks_get_from_id_ext(GList *forms, int id);
dt_masks_form_t *dt_masks_get_from_id(dt_develop_t *dev, int id);
int dt_masks_copy_used_forms_for_module(dt_develop_t *dev_dest, dt_develop_t *dev_src,
                                        const struct dt_iop_module_t *mod_src);
struct dt_iop_module_t *dt_masks_get_mask_manager(struct dt_develop_t *dev);
 
void dt_masks_read_masks_history(dt_develop_t *dev, const int32_t imgid);
void dt_masks_write_masks_history_item(const int32_t imgid, const int num, dt_masks_form_t *form);
void dt_masks_free_form(dt_masks_form_t *form);
void dt_masks_cleanup_unused(dt_develop_t *dev);
 
void dt_masks_change_form_gui(dt_masks_form_t *newform);
void dt_masks_clear_form_gui(dt_develop_t *dev);
void dt_masks_reset_form_gui(void);
void dt_masks_soft_reset_form_gui(dt_masks_form_gui_t *gui);
void dt_masks_reset_show_masks_icons(void);
 
int dt_masks_events_mouse_moved(struct dt_iop_module_t *module, double x, double y, double pressure,
                                int which);
int dt_masks_events_button_released(struct dt_iop_module_t *module, double x, double y, int which,
                                    uint32_t state);
int dt_masks_events_button_pressed(struct dt_iop_module_t *module, double x, double y, double pressure,
                                   int which, int type, uint32_t state);
int dt_masks_events_mouse_scrolled(struct dt_iop_module_t *module, double x, double y, int up, uint32_t state, int delta_y);
 
int dt_masks_events_key_pressed(struct dt_iop_module_t *module, GdkEventKey *event);
gboolean dt_masks_node_is_cusp(const dt_masks_form_gui_points_t *gpt, const int index);
 
void dt_masks_draw_source(cairo_t *cr, dt_masks_form_gui_t *gui, const int index, const int nb, 
  const float zoom_scale, struct dt_masks_gui_center_point_t *center_point, const shape_draw_function_t *draw_shape_func);
void dt_masks_draw_path_seg_by_seg(cairo_t *cr, dt_masks_form_gui_t *gui, const int index, const float *points,
                                   const int points_count, const int node_count, const float zoom_scale);
 
void dt_masks_events_post_expose(struct dt_iop_module_t *module, cairo_t *cr, int32_t width, int32_t height,
                                 int32_t pointerx, int32_t pointery);
int dt_masks_events_mouse_leave(struct dt_iop_module_t *module);
int dt_masks_events_mouse_enter(struct dt_iop_module_t *module);
 
void dt_masks_gui_form_create(dt_masks_form_t *form, dt_masks_form_gui_t *gui, int index,
                              struct dt_iop_module_t *module);
gboolean dt_masks_gui_form_create_throttled(dt_masks_form_t *form, dt_masks_form_gui_t *gui, int index,
                                            struct dt_iop_module_t *module, float posx, float posy);
 
gboolean dt_masks_gui_delete(struct dt_iop_module_t *module, dt_masks_form_t *form, dt_masks_form_gui_t *gui, const int parentid);
 
// Remove a mask
gboolean dt_masks_form_cancel_creation(dt_iop_module_t *module, dt_masks_form_gui_t *gui);
 
 
void dt_masks_gui_form_remove(dt_masks_form_t *form, dt_masks_form_gui_t *gui, int index);
void dt_masks_gui_form_test_create(dt_masks_form_t *form, dt_masks_form_gui_t *gui, struct dt_iop_module_t *module);
void dt_masks_gui_form_save_creation(dt_develop_t *dev, struct dt_iop_module_t *module, dt_masks_form_t *form,
                                     dt_masks_form_gui_t *gui);
void dt_masks_group_ungroup(dt_masks_form_t *dest_grp, dt_masks_form_t *grp);
void dt_masks_group_update_name(dt_iop_module_t *module);
dt_masks_form_group_t *dt_masks_group_add_form(dt_masks_form_t *grp, dt_masks_form_t *form);
 
void dt_masks_iop_value_changed_callback(GtkWidget *widget, struct dt_iop_module_t *module);
dt_masks_edit_mode_t dt_masks_get_edit_mode(struct dt_iop_module_t *module);
void dt_masks_set_edit_mode(struct dt_iop_module_t *module, dt_masks_edit_mode_t value);
void dt_masks_iop_update(struct dt_iop_module_t *module);
void dt_masks_iop_combo_populate(GtkWidget *w, void *module);
void dt_masks_iop_use_same_as(struct dt_iop_module_t *module, struct dt_iop_module_t *src);
uint64_t dt_masks_group_get_hash(uint64_t hash, dt_masks_form_t *form);
 
void dt_masks_form_remove(struct dt_iop_module_t *module, dt_masks_form_t *grp, dt_masks_form_t *form);
int dt_masks_form_change_opacity(dt_masks_form_t *form, int parentid, int up, const int flow);
void dt_masks_form_move(dt_masks_form_t *grp, int formid, int up);
int dt_masks_form_duplicate(dt_develop_t *dev, int formid);
/* returns a duplicate tof form, including the formid */
dt_masks_form_t *dt_masks_dup_masks_form(const dt_masks_form_t *form);
/* duplicate the list of forms, replace item in the list with form with the same formid */
GList *dt_masks_dup_forms_deep(GList *forms, dt_masks_form_t *form);
 
int dt_masks_point_in_form_exact(const float *pts, int num_pts, const float *points, int points_start, int points_count);
 
void dt_masks_select_form(struct dt_iop_module_t *module, dt_masks_form_t *sel);
 
void dt_masks_set_source_pos_initial_state(dt_masks_form_gui_t *gui, const uint32_t state);
void dt_masks_set_source_pos_initial_value(dt_masks_form_gui_t *gui, dt_masks_form_t *form);
void dt_masks_calculate_source_pos_value(dt_masks_form_gui_t *gui, const float initial_xpos,
                                         const float initial_ypos, const float xpos, const float ypos, float *px,
                                         float *py, const int adding);
static inline void dt_masks_draw_source_preview(cairo_t *cr, const float zoom_scale, dt_masks_form_gui_t *gui,
                                                const float initial_xpos, const float initial_ypos,
                                                const float xpos, const float ypos, const int adding)
{
  float source_pos[2] = { 0.0f, 0.0f };
  dt_masks_calculate_source_pos_value(gui, initial_xpos, initial_ypos, xpos, ypos,
                                      &source_pos[0], &source_pos[1], adding);
  dt_draw_cross(cr, zoom_scale, source_pos[0], source_pos[1]);
}
float dt_masks_rotate_with_anchor(dt_develop_t *dev, const float anchor[2], const float center[2], dt_masks_form_gui_t *gui);
 
dt_masks_form_group_t *dt_masks_form_group_from_parentid(int parentid, int formid);
int dt_masks_group_index_from_formid(const dt_masks_form_t *group_form, int formid);
dt_masks_form_group_t *dt_masks_form_get_selected_group(const struct dt_masks_form_t *form,
                                                        const struct dt_masks_form_gui_t *gui);
 
gboolean dt_masks_is_anything_selected(const dt_masks_form_gui_t *mask_gui);
 
gboolean dt_masks_is_anything_hovered(const dt_masks_form_gui_t *mask_gui);
 
dt_masks_form_group_t *dt_masks_form_get_selected_group_live(const struct dt_masks_form_t *form,
                                                             const struct dt_masks_form_gui_t *gui);
float dt_masks_form_get_interaction_value(dt_masks_form_group_t *form_group,
                                          dt_masks_interaction_t interaction);
gboolean dt_masks_form_get_gravity_center(const struct dt_masks_form_t *form, float center[2], float *area);
void dt_masks_form_update_gravity_center(struct dt_masks_form_t *form);
float dt_masks_form_set_interaction_value(dt_masks_form_group_t *form_group,
                                          dt_masks_interaction_t interaction,
                                          float value, dt_masks_increment_t increment, int flow,
                                          struct dt_masks_form_gui_t *gui, struct dt_iop_module_t *module);
 
float dt_masks_get_set_conf_value(dt_masks_form_t *form, char *feature, float new_value, float v_min, float v_max,
                                  dt_masks_increment_t increment, const int flow);
float dt_masks_get_set_conf_value_with_toast(dt_masks_form_t *form, const char *feature, float amount,
                                             float v_min, float v_max, dt_masks_increment_t increment, int flow,
                                             const char *toast_fmt, float toast_scale);
 
void dt_masks_duplicate_points(const dt_masks_form_t *base, dt_masks_form_t *dest, size_t node_size);
 
float dt_masks_apply_increment(float current, float amount, dt_masks_increment_t increment, int flow);
 
float dt_masks_apply_increment_precomputed(float current, float amount, float scale_amount, float offset_amount,
                                            dt_masks_increment_t increment);
 
void dt_masks_extend_border(float *const mask, const int width, const int height, const int border);
void dt_masks_blur_9x9_coeff(float *coeffs, const float sigma);
void dt_masks_blur_9x9(float *const src, float *const out, const int width, const int height, const float sigma);
void dt_masks_calc_rawdetail_mask(float *const src, float *const out, float *const tmp, const int width,
                                  const int height, const dt_aligned_pixel_t wb);
void dt_masks_calc_detail_mask(float *const src, float *const out, float *const tmp, const int width, const int height, const float threshold, const gboolean detail);
 
void dt_group_events_post_expose(cairo_t *cr, float zoom_scale, dt_masks_form_t *form,
                                 dt_masks_form_gui_t *gui);
 
static inline gboolean _dt_masks_dynbuf_growto(dt_masks_dynbuf_t *a, size_t size)
{
  const size_t newsize = dt_round_size_sse(sizeof(float) * size) / sizeof(float);
  float *newbuf = dt_pixelpipe_cache_alloc_align_float_cache(newsize, 0);
  if (!newbuf)
  {
    // not much we can do here except emit an error message
    fprintf(stderr, "critical: out of memory for dynbuf '%s' with size request %zu!\n", a->tag, size);
    return FALSE;
  }
  if (a->buffer)
  {
    memcpy(newbuf, a->buffer, a->size * sizeof(float));
    dt_print(DT_DEBUG_MASKS, "[masks dynbuf '%s'] grows to size %lu (is %p, was %p)\n", a->tag,
             (unsigned long)a->size, newbuf, a->buffer);
    dt_pixelpipe_cache_free_align(a->buffer);
  }
  a->size = newsize;
  a->buffer = newbuf;
  return TRUE;
}
 
static inline dt_masks_dynbuf_t *dt_masks_dynbuf_init(size_t size, const char *tag)
{
  assert(size > 0);
  dt_masks_dynbuf_t *a = (dt_masks_dynbuf_t *)calloc(1, sizeof(dt_masks_dynbuf_t));
 
  if(a != NULL)
  {
    g_strlcpy(a->tag, tag, sizeof(a->tag)); //only for debugging purposes
    a->pos = 0;
    if(_dt_masks_dynbuf_growto(a, size))
      dt_print(DT_DEBUG_MASKS, "[masks dynbuf '%s'] with initial size %lu (is %p)\n", a->tag,
               (unsigned long)a->size, a->buffer);
    if(a->buffer == NULL)
    {
      dt_free(a);
    }
  }
  return a;
}
 
static inline void dt_masks_dynbuf_add_2(dt_masks_dynbuf_t *a, float value1, float value2)
{
  assert(a != NULL);
  assert(a->pos <= a->size);
  if(__builtin_expect(a->pos + 2 >= a->size, 0))
  {
    if (a->size == 0 || !_dt_masks_dynbuf_growto(a, 2 * (a->size+1)))
      return;
  }
  a->buffer[a->pos++] = value1;
  a->buffer[a->pos++] = value2;
}
 
// Return a pointer to N floats past the current end of the dynbuf's contents, marking them as already in use.
// The caller should then fill in the reserved elements using the returned pointer.
static inline float *dt_masks_dynbuf_reserve_n(dt_masks_dynbuf_t *a, const int n)
{
  assert(a != NULL);
  assert(a->pos <= a->size);
  if(__builtin_expect(a->pos + n >= a->size, 0))
  {
    if(a->size == 0) return NULL;
    size_t newsize = a->size;
    while(a->pos + n >= newsize) newsize *= 2;
    if (!_dt_masks_dynbuf_growto(a, newsize))
    {
      return NULL;
    }
  }
  // get the current end of the (possibly reallocated) buffer, then mark the next N items as in-use
  float *reserved = a->buffer + a->pos;
  a->pos += n;
  return reserved;
}
 
static inline void dt_masks_dynbuf_add_zeros(dt_masks_dynbuf_t *a, const int n)
{
  assert(a != NULL);
  assert(a->pos <= a->size);
  if(__builtin_expect(a->pos + n >= a->size, 0))
  {
    if(a->size == 0) return;
    size_t newsize = a->size;
    while(a->pos + n >= newsize) newsize *= 2;
    if (!_dt_masks_dynbuf_growto(a, newsize))
    {
      return;
    }
  }
  // now that we've ensured a sufficiently large buffer add N zeros to the end of the existing data
  memset(a->buffer + a->pos, 0, n * sizeof(float));
  a->pos += n;
}
 
 
static inline float dt_masks_dynbuf_get(dt_masks_dynbuf_t *a, int offset)
{
  assert(a != NULL);
  // offset: must be negative distance relative to end of buffer
  assert(offset < 0);
  assert((long)a->pos + offset >= 0);
  return (a->buffer[a->pos + offset]);
}
 
static inline void dt_masks_dynbuf_set(dt_masks_dynbuf_t *a, int offset, float value)
{
  assert(a != NULL);
  // offset: must be negative distance relative to end of buffer
  assert(offset < 0);
  assert((long)a->pos + offset >= 0);
  a->buffer[a->pos + offset] = value;
}
 
static inline float *dt_masks_dynbuf_buffer(dt_masks_dynbuf_t *a)
{
  assert(a != NULL);
  return a->buffer;
}
 
static inline gboolean dt_masks_center_of_gravity_from_points(const float *points, const int points_count,
                                                              float center[2], float *area)
{
  if(!points || !center || !area || points_count <= 0)
  {
    if(center)
    {
      center[0] = 0.0f;
      center[1] = 0.0f;
    }
    if(area) *area = 0.0f;
    return FALSE;
  }
 
  double start = 0.;
  if(darktable.unmuted & DT_DEBUG_PERF) start = dt_get_wtime();
 
  // Points must be ordered sequentially along the polygon boundary.
  // Use the shoelace formula to compute area and centroid.
  if(points_count >= 3)
  {
    double area2 = 0.0;
    double cx = 0.0;
    double cy = 0.0;
 
    for(int i = 0; i < points_count; i++)
    {
      const int j = (i + 1 < points_count) ? (i + 1) : 0;
      const double x0 = points[i * 2];
      const double y0 = points[i * 2 + 1];
      const double x1 = points[j * 2];
      const double y1 = points[j * 2 + 1];
 
      const double cross = x0 * y1 - x1 * y0;
      area2 += cross;
      cx += (x0 + x1) * cross;
      cy += (y0 + y1) * cross;
    }
 
    if(fabs(area2) > 1e-12)
    {
      const double inv = 1.0 / (3.0 * area2);
      center[0] = (float)(cx * inv);
      center[1] = (float)(cy * inv);
 
      *area = (float)(0.5 * fabs(area2));
      return TRUE;
    }
  }
 
  // Fallback to arithmetic mean for degenerate polygons or short lists.
  float sum_x = 0.0f;
  float sum_y = 0.0f;
  const float inv_count = 1.0f / (float)points_count;
  for(int i = 0; i < points_count; i++)
  {
    sum_x += points[i * 2] * inv_count;
    sum_y += points[i * 2 + 1] * inv_count;
  }
 
  if(darktable.unmuted & DT_DEBUG_PERF)
    dt_print(DT_DEBUG_MASKS, "[masks] computing centroid took %0.04f sec\n",
             dt_get_wtime() - start);
 
 
  center[0] = sum_x;
  center[1] = sum_y;
  *area = 0.0f;
  return TRUE;
}
 
static inline size_t dt_masks_dynbuf_position(dt_masks_dynbuf_t *a)
{
  assert(a != NULL);
  return a->pos;
}
 
static inline void dt_masks_dynbuf_reset(dt_masks_dynbuf_t *a)
{
  assert(a != NULL);
  a->pos = 0;
}
 
static inline float *dt_masks_dynbuf_harvest(dt_masks_dynbuf_t *a)
{
  // take out data buffer and make dynamic buffer obsolete
  if(a == NULL) return NULL;
  float *r = a->buffer;
  a->buffer = NULL;
  a->pos = a->size = 0;
  return r;
}
 
static inline void dt_masks_dynbuf_free(dt_masks_dynbuf_t *a)
{
  if(a == NULL) return;
  dt_print(DT_DEBUG_MASKS, "[masks dynbuf '%s'] freed (was %p)\n", a->tag,
          a->buffer);
  dt_pixelpipe_cache_free_align(a->buffer);
  dt_free(a);
}
 
static inline int dt_masks_roundup(int num, int mult)
{
  const int rem = num % mult;
 
  return (rem == 0) ? num : num + mult - rem;
}
 
gboolean dt_masks_point_is_within_radius(const float px, const float py,
                                        const float cx, const float cy,
                                        const float radius);
 
typedef gboolean (*dt_masks_border_handle_fn)(const dt_masks_form_gui_points_t *gui_points, int node_count,
                                              int node_index, float *handle_x, float *handle_y, void *user_data);
typedef void (*dt_masks_curve_handle_fn)(const dt_masks_form_gui_points_t *gui_points, int node_index,
                                         float *handle_x, float *handle_y, void *user_data);
typedef void (*dt_masks_node_position_fn)(const dt_masks_form_gui_points_t *gui_points, int node_index,
                                          float *node_x, float *node_y, void *user_data);
typedef void (*dt_masks_distance_fn)(float pointer_x, float pointer_y, float cursor_radius,
                                     dt_masks_form_gui_t *mask_gui, int form_index, int node_count,
                                     int *inside, int *inside_border, int *near, int *inside_source, float *dist,
                                     void *user_data);
typedef void (*dt_masks_post_select_fn)(dt_masks_form_gui_t *mask_gui, int inside, int inside_border,
                                        int inside_source, void *user_data);
 
int dt_masks_find_closest_handle_common(dt_masks_form_t *mask_form, dt_masks_form_gui_t *mask_gui,
                                        int form_index, int node_count_override,
                                        dt_masks_border_handle_fn border_handle_cb,
                                        dt_masks_curve_handle_fn curve_handle_cb,
                                        dt_masks_node_position_fn node_position_cb,
                                        dt_masks_distance_fn distance_cb,
                                        dt_masks_post_select_fn post_select_cb,
                                        void *user_data);
 
gboolean dt_masks_creation_mode(dt_iop_module_t *module, const dt_masks_type_t type);
void apply_operation(struct dt_masks_form_group_t *pt, const dt_masks_state_t apply_state);
 
#define menu_item_set_fake_accel(menu_item, keyval, mods)             \
                                                                      \
{                                                                     \
  GtkWidget *child = gtk_bin_get_child(GTK_BIN(menu_item));           \
  if(GTK_IS_ACCEL_LABEL(child))                                       \
    gtk_accel_label_set_accel(GTK_ACCEL_LABEL(child), keyval, mods);  \
}
 
void _masks_gui_delete_node_callback(GtkWidget *menu, gpointer user_data);
 
GdkModifierType dt_masks_get_accel_mods(dt_masks_interaction_t interaction);
 
GtkWidget *dt_masks_create_menu(dt_masks_form_gui_t *gui, dt_masks_form_t *form, const dt_masks_form_group_t *fpt,
                                const float pzx, const float pzy);
 
#ifdef __cplusplus
}
#endif
 
// clang-format off
// modelines: These editor modelines have been set for all relevant files by tools/update_modelines.py
// vim: shiftwidth=2 expandtab tabstop=2 cindent
// kate: tab-indents: off; indent-width 2; replace-tabs on; indent-mode cstyle; remove-trailing-spaces modified;
// clang-format on