#include "CLG_log.h"
#include "MEM_guardedalloc.h"
#include "BLI_blenlib.h"
#include "BLI_math.h"
#include "BLI_threads.h"
#include "BLI_utildefines.h"
#include "DNA_image_types.h"
#include "DNA_object_types.h"
#include "DNA_screen_types.h"
#include "DNA_space_types.h"
#include "DNA_windowmanager_types.h"
#include "IMB_imbuf.h"
#include "IMB_imbuf_types.h"
#include "BKE_context.h"
#include "BKE_image.h"
#include "BKE_paint.h"
#include "BKE_undo_system.h"
#include "DEG_depsgraph.h"
#include "ED_object.h"
#include "ED_paint.h"
#include "ED_undo.h"
#include "ED_util.h"
#include "WM_api.h"

Classes
struct	PaintTile

struct	UndoImageTile

struct	UndoImageBuf

struct	UndoImageHandle

struct	ImageUndoStep

Functions
Image Undo Internal Utilities
static UndoImageBuf *	uhandle_lookup_ubuf (UndoImageHandle uh, const Image UNUSED(image), const char *ibuf_name)

static UndoImageBuf *	uhandle_add_ubuf (UndoImageHandle uh, Image image, ImBuf *ibuf)

static UndoImageBuf *	uhandle_ensure_ubuf (UndoImageHandle uh, Image image, ImBuf *ibuf)

static UndoImageHandle *	uhandle_lookup_by_name (ListBase undo_handles, const Image image, int tile_number)

static UndoImageHandle *	uhandle_lookup (ListBase undo_handles, const Image image, int tile_number)

static UndoImageHandle *	uhandle_add (ListBase undo_handles, Image image, ImageUser *iuser)

static UndoImageHandle *	uhandle_ensure (ListBase undo_handles, Image image, ImageUser *iuser)

Utilities
Note image undo exposes ED_image_undo_push_begin, ED_image_undo_push_end which must be called by the operator directly. Unlike most other undo stacks this is needed: So we can always access the state before the image was painted onto, which is needed if previous undo states aren't image-type. So operators can access the pixel-data before the stroke was applied, at run-time.
ListBase *	ED_image_paint_tile_list_get (void)

void	ED_image_undo_restore (UndoStep *us)

static ImageUndoStep *	image_undo_push_begin (const char *name, int paint_mode)

void	ED_image_undo_push_begin (const char *name, int paint_mode)

void	ED_image_undo_push_begin_with_image (const char name, Image image, ImBuf ibuf, ImageUser iuser)

void	ED_image_undo_push_end (void)

Variables
static CLG_LogRef	LOG = {"ed.image.undo"}

Paint Tiles
Created on demand while painting, use to access the previous state for some paint operations. These buffers are also used for undo when available.
typedef struct PaintTile	PaintTile

static ImBuf *	imbuf_alloc_temp_tile (void)

static void	ptile_free (PaintTile *ptile)

static void	ptile_free_list (ListBase *paint_tiles)

static void	ptile_invalidate_list (ListBase *paint_tiles)

void *	ED_image_paint_tile_find (ListBase paint_tiles, Image image, ImBuf ibuf, ImageUser iuser, int x_tile, int y_tile, ushort **r_mask, bool validate)

void *	ED_image_paint_tile_push (ListBase paint_tiles, Image image, ImBuf ibuf, ImBuf tmpibuf, ImageUser iuser, int x_tile, int y_tile, ushort r_mask, bool r_valid, bool use_thread_lock, bool find_prev)

static void	ptile_restore_runtime_list (ListBase *paint_tiles)

Image Undo Tile
typedef struct UndoImageTile	UndoImageTile

static uint	index_from_xy (uint tile_x, uint tile_y, const uint tiles_dims[2])

static UndoImageTile *	utile_alloc (bool has_float)

static void	utile_init_from_imbuf (UndoImageTile utile, const uint x, const uint y, const ImBuf ibuf, ImBuf *tmpibuf)

static void	utile_restore (const UndoImageTile utile, const uint x, const uint y, ImBuf ibuf, ImBuf *tmpibuf)

static void	utile_decref (UndoImageTile *utile)

Image Undo Buffer
typedef struct UndoImageBuf	UndoImageBuf

static UndoImageBuf *	ubuf_from_image_no_tiles (Image image, const ImBuf ibuf)

static void	ubuf_from_image_all_tiles (UndoImageBuf ubuf, const ImBuf ibuf)

static void	ubuf_ensure_compat_ibuf (const UndoImageBuf ubuf, ImBuf ibuf)

static void	ubuf_free (UndoImageBuf *ubuf)

Image Undo Handle
typedef struct UndoImageHandle	UndoImageHandle

static void	uhandle_restore_list (ListBase *undo_handles, bool use_init)

static void	uhandle_free_list (ListBase *undo_handles)

Implements ED Undo System
typedef struct ImageUndoStep	ImageUndoStep

static UndoImageBuf *	ubuf_lookup_from_reference (ImageUndoStep us_prev, const Image image, int tile_number, const UndoImageBuf *ubuf)

static bool	image_undosys_poll (bContext *C)

static void	image_undosys_step_encode_init (struct bContext UNUSED(C), UndoStep us_p)

static bool	image_undosys_step_encode (struct bContext C, struct Main UNUSED(bmain), UndoStep *us_p)

static void	image_undosys_step_decode_undo_impl (ImageUndoStep *us, bool is_final)

static void	image_undosys_step_decode_redo_impl (ImageUndoStep *us)

static void	image_undosys_step_decode_undo (ImageUndoStep *us, bool is_final)

static void	image_undosys_step_decode_redo (ImageUndoStep *us)

static void	image_undosys_step_decode (struct bContext C, struct Main bmain, UndoStep *us_p, const eUndoStepDir dir, bool is_final)

static void	image_undosys_step_free (UndoStep *us_p)

static void	image_undosys_foreach_ID_ref (UndoStep us_p, UndoTypeForEachIDRefFn foreach_ID_ref_fn, void user_data)

void	ED_image_undosys_type (UndoType *ut)

Thread Locking
static SpinLock	paint_tiles_lock

void	ED_image_paint_tile_lock_init (void)

void	ED_image_paint_tile_lock_end (void)

Detailed Description

Overview

Each undo step is a ImageUndoStep
Each ImageUndoStep stores a list of UndoImageHandle
- Each UndoImageHandle stores a list of UndoImageBuf (this is the undo systems equivalent of an ImBuf).
  - Each UndoImageBuf stores an array of UndoImageTile The tiles are shared between UndoImageBuf's to avoid duplication.

When the undo system manages an image, there will always be a full copy (as a UndoImageBuf) each new undo step only stores modified tiles.

Definition in file image_undo.c.

Typedef Documentation

◆ ImageUndoStep

typedef struct ImageUndoStep ImageUndoStep

◆ PaintTile

typedef struct PaintTile PaintTile

◆ UndoImageBuf

typedef struct UndoImageBuf UndoImageBuf

◆ UndoImageHandle

typedef struct UndoImageHandle UndoImageHandle

◆ UndoImageTile

typedef struct UndoImageTile UndoImageTile

Function Documentation

◆ ED_image_paint_tile_find()

void* ED_image_paint_tile_find	(	ListBase *	paint_tiles,
		Image *	image,
		ImBuf *	ibuf,
		ImageUser *	iuser,
		int	x_tile,
		int	y_tile,
		ushort **	r_mask,
		bool	validate
	)

Definition at line 151 of file image_undo.c.

References ED_IMAGE_UNDO_TILE_SIZE, LISTBASE_FOREACH, MEM_callocN, NULL, square_i(), and ImageUser::tile.

Referenced by ED_image_paint_tile_push(), and paint_2d_do_making_brush().

◆ ED_image_paint_tile_list_get()

ListBase* ED_image_paint_tile_list_get ( void )

Definition at line 1027 of file image_undo.c.

References BKE_undosys_stack_init_or_active_with_type(), BKE_UNDOSYS_TYPE_IMAGE, BLI_assert, ED_undo_stack_get(), ImageUndoStep::paint_mode, PAINT_MODE_TEXTURE_2D, ImageUndoStep::paint_tiles, and UndoStack::step_init.

Referenced by ED_imapaint_dirty_region(), paint_2d_do_making_brush(), and project_paint_undo_subtiles().

◆ ED_image_paint_tile_lock_end()

void ED_image_paint_tile_lock_end ( void )

Definition at line 81 of file image_undo.c.

References BLI_spin_end(), and paint_tiles_lock.

Referenced by project_paint_end().

◆ ED_image_paint_tile_lock_init()

void ED_image_paint_tile_lock_init ( void )

Definition at line 76 of file image_undo.c.

References BLI_spin_init(), and paint_tiles_lock.

Referenced by proj_paint_state_thread_init().

◆ ED_image_paint_tile_push()

void* ED_image_paint_tile_push	(	ListBase *	paint_tiles,
		Image *	image,
		ImBuf *	ibuf,
		ImBuf **	tmpibuf,
		ImageUser *	iuser,
		int	x_tile,
		int	y_tile,
		ushort **	r_mask,
		bool **	r_valid,
		bool	use_thread_lock,
		bool	find_prev
	)