greasepencil_tools/box_deform.py

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  15 #  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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  17 # ##### END GPL LICENSE BLOCK #####
  18
  19 '''Based on Box_deform standalone addon - Author: Samuel Bernou'''
  20
  21 from .prefs import get_addon_prefs
  22
  23 import bpy
  24 import numpy as np
  25
  26 def location_to_region(worldcoords):
  27     from bpy_extras import view3d_utils
  28     return view3d_utils.location_3d_to_region_2d(bpy.context.region, bpy.context.space_data.region_3d, worldcoords)
  29
  30 def region_to_location(viewcoords, depthcoords):
  31     from bpy_extras import view3d_utils
  32     return view3d_utils.region_2d_to_location_3d(bpy.context.region, bpy.context.space_data.region_3d, viewcoords, depthcoords)
  33
  34 def store_cage(self, vg_name):
  35     import time
  36     unique_id = time.strftime(r'%y%m%d%H%M%S') # ex: 20210711111117
  37     # name = f'gp_lattice_{unique_id}'
  38     name = f'{self.gp_obj.name}_lat{unique_id}'
  39     vg = self.gp_obj.vertex_groups.get(vg_name)
  40     if vg:
  41         vg.name = name
  42     for o in self.other_gp:
  43         vg = o.vertex_groups.get(vg_name)
  44         if vg:
  45             vg.name = name
  46
  47     self.cage.name = name
  48     self.cage.data.name = name
  49     mod = self.gp_obj.grease_pencil_modifiers.get('tmp_lattice')
  50     if mod:
  51         mod.name = name #f'Lattice_{unique_id}'
  52         mod.vertex_group = name
  53     for o in self.other_gp:
  54         mod = o.grease_pencil_modifiers.get('tmp_lattice')
  55         if mod:
  56             mod.name = name
  57             mod.vertex_group = name
  58
  59 def assign_vg(obj, vg_name, delete=False):
  60     ## create vertex group
  61     vg = obj.vertex_groups.get(vg_name)
  62     if vg:
  63         # remove to start clean
  64         obj.vertex_groups.remove(vg)
  65     if delete:
  66         return
  67
  68     vg = obj.vertex_groups.new(name=vg_name)
  69     bpy.ops.gpencil.vertex_group_assign()
  70     return vg
  71
  72 def view_cage(obj):
  73     prefs = get_addon_prefs()
  74     lattice_interp = prefs.default_deform_type
  75
  76     gp = obj.data
  77     gpl = gp.layers
  78
  79     from_obj = bpy.context.mode == 'OBJECT'
  80     all_gps = [o for o in bpy.context.selected_objects if o.type == 'GPENCIL']
  81     other_gp = [o for o in all_gps if o is not obj]
  82
  83     coords = []
  84     initial_mode = bpy.context.mode
  85
  86     ## get points
  87     if bpy.context.mode == 'EDIT_GPENCIL':
  88         for l in gpl:
  89             if l.lock or l.hide or not l.active_frame:#or len(l.frames)
  90                 continue
  91             if gp.use_multiedit:
  92                 target_frames = [f for f in l.frames if f.select]
  93             else:
  94                 target_frames = [l.active_frame]
  95
  96             for f in target_frames:
  97                 for s in f.strokes:
  98                     if not s.select:
  99                         continue
 100                     for p in s.points:
 101                         if p.select:
 102                             # get real location
 103                             coords.append(obj.matrix_world @ p.co)
 104
 105     elif bpy.context.mode == 'OBJECT': # object mode -> all points of all selected gp objects
 106         for gpo in all_gps:
 107             for l in gpo.data.layers:# if l.hide:continue# only visible ? (might break things)
 108                 if not len(l.frames):
 109                     continue # skip frameless layer
 110                 for s in l.active_frame.strokes:
 111                     for p in s.points:
 112                         coords.append(gpo.matrix_world @ p.co)
 113
 114     elif bpy.context.mode == 'PAINT_GPENCIL':
 115         # get last stroke points coordinated
 116         if not gpl.active or not gpl.active.active_frame:
 117             return 'No frame to deform'
 118
 119         if not len(gpl.active.active_frame.strokes):
 120             return 'No stroke found to deform'
 121
 122         paint_id = -1
 123         if bpy.context.scene.tool_settings.use_gpencil_draw_onback:
 124             paint_id = 0
 125         coords = [obj.matrix_world @ p.co for p in gpl.active.active_frame.strokes[paint_id].points]
 126
 127     else:
 128         return 'Wrong mode!'
 129
 130     if not coords:
 131         ## maybe silent return instead (need special str code to manage errorless return)
 132         return 'No points found!'
 133
 134     if bpy.context.mode in ('EDIT_GPENCIL', 'PAINT_GPENCIL') and len(coords) < 2:
 135         # Dont block object mod
 136         return 'Less than two point selected'
 137
 138     vg_name = 'lattice_cage_deform_group'
 139
 140     if bpy.context.mode == 'EDIT_GPENCIL':
 141         vg = assign_vg(obj, vg_name)
 142
 143     if bpy.context.mode == 'PAINT_GPENCIL':
 144         # points cannot be assign to API yet(ugly and slow workaround but only way)
 145         # -> https://developer.blender.org/T56280 so, hop'in'ops !
 146
 147         # store selection and deselect all
 148         plist = []
 149         for s in gpl.active.active_frame.strokes:
 150             for p in s.points:
 151                 plist.append([p, p.select])
 152                 p.select = False
 153
 154         # select
 155         ## foreach_set does not update
 156         # gpl.active.active_frame.strokes[paint_id].points.foreach_set('select', [True]*len(gpl.active.active_frame.strokes[paint_id].points))
 157         for p in gpl.active.active_frame.strokes[paint_id].points:
 158             p.select = True
 159
 160         # assign
 161         bpy.ops.object.mode_set(mode='EDIT_GPENCIL')
 162         vg = assign_vg(obj, vg_name)
 163
 164         # restore
 165         for pl in plist:
 166             pl[0].select = pl[1]
 167
 168
 169     ## View axis Mode ---
 170
 171     ## get view coordinate of all points
 172     coords2D = [location_to_region(co) for co in coords]
 173
 174     # find centroid for depth (or more economic, use obj origin...)
 175     centroid = np.mean(coords, axis=0)
 176
 177     # not a mean ! a mean of extreme ! centroid2d = np.mean(coords2D, axis=0)
 178     all_x, all_y = np.array(coords2D)[:, 0], np.array(coords2D)[:, 1]
 179     min_x, min_y = np.min(all_x), np.min(all_y)
 180     max_x, max_y = np.max(all_x), np.max(all_y)
 181
 182     width = (max_x - min_x)
 183     height = (max_y - min_y)
 184     center_x = min_x + (width/2)
 185     center_y = min_y + (height/2)
 186
 187     centroid2d = (center_x,center_y)
 188     center = region_to_location(centroid2d, centroid)
 189     # bpy.context.scene.cursor.location = center#Dbg
 190
 191
 192     #corner Bottom-left to Bottom-right
 193     x0 = region_to_location((min_x, min_y), centroid)
 194     x1 = region_to_location((max_x, min_y), centroid)
 195     x_worldsize = (x0 - x1).length
 196
 197     #corner Bottom-left to top-left
 198     y0 = region_to_location((min_x, min_y), centroid)
 199     y1 = region_to_location((min_x, max_y), centroid)
 200     y_worldsize = (y0 - y1).length
 201
 202     ## in case of 3
 203
 204     lattice_name = 'lattice_cage_deform'
 205     # cleaning
 206     cage = bpy.data.objects.get(lattice_name)
 207     if cage:
 208         bpy.data.objects.remove(cage)
 209
 210     lattice = bpy.data.lattices.get(lattice_name)
 211     if lattice:
 212         bpy.data.lattices.remove(lattice)
 213
 214     # create lattice object
 215     lattice = bpy.data.lattices.new(lattice_name)
 216     cage = bpy.data.objects.new(lattice_name, lattice)
 217     cage.show_in_front = True
 218
 219     ## Master (root) collection
 220     bpy.context.scene.collection.objects.link(cage)
 221
 222     # spawn cage and align it to view
 223
 224     r3d = bpy.context.space_data.region_3d
 225     viewmat = r3d.view_matrix
 226
 227     cage.matrix_world = viewmat.inverted()
 228     cage.scale = (x_worldsize, y_worldsize, 1)
 229     ## Z aligned in view direction (need minus X 90 degree to be aligned FRONT)
 230     # cage.rotation_euler.x -= radians(90)
 231     # cage.scale = (x_worldsize, 1, y_worldsize)
 232     cage.location = center
 233
 234     lattice.points_u = 2
 235     lattice.points_v = 2
 236     lattice.points_w = 1
 237
 238     lattice.interpolation_type_u = lattice_interp #'KEY_LINEAR'-'KEY_BSPLINE'
 239     lattice.interpolation_type_v = lattice_interp
 240     lattice.interpolation_type_w = lattice_interp
 241
 242     mod = obj.grease_pencil_modifiers.new('tmp_lattice', 'GP_LATTICE')
 243     if from_obj:
 244         mods = []
 245         for o in other_gp:
 246             mods.append( o.grease_pencil_modifiers.new('tmp_lattice', 'GP_LATTICE') )
 247
 248     # move to top if modifiers exists
 249     for _ in range(len(obj.grease_pencil_modifiers)):
 250         bpy.ops.object.gpencil_modifier_move_up(modifier='tmp_lattice')
 251     if from_obj:
 252         for o in other_gp:
 253             for _ in range(len(o.grease_pencil_modifiers)):
 254                 bpy.ops.object.gpencil_modifier_move_up({'object':o}, modifier='tmp_lattice')
 255
 256     mod.object = cage
 257     if from_obj:
 258         for m in mods:
 259             m.object = cage
 260
 261     if initial_mode == 'PAINT_GPENCIL':
 262         mod.layer = gpl.active.info
 263
 264     # note : if initial was Paint, changed to Edit
 265     #        so vertex attribution is valid even for paint
 266     if bpy.context.mode == 'EDIT_GPENCIL':
 267         mod.vertex_group = vg.name
 268
 269     # Go in object mode if not already
 270     if bpy.context.mode != 'OBJECT':
 271         bpy.ops.object.mode_set(mode='OBJECT')
 272
 273     # Store name of deformed object in case of 'revive modal'
 274     cage.vertex_groups.new(name=obj.name)
 275     if from_obj:
 276         for o in other_gp:
 277             cage.vertex_groups.new(name=o.name)
 278
 279     ## select and make cage active
 280     # cage.select_set(True)
 281     bpy.context.view_layer.objects.active = cage
 282     obj.select_set(False) # deselect GP object
 283     bpy.ops.object.mode_set(mode='EDIT') # go in lattice edit mode
 284     bpy.ops.lattice.select_all(action='SELECT') # select all points
 285
 286     if prefs.use_clic_drag:
 287         ## Eventually change tool mode to tweak for direct point editing (reset after before leaving)
 288         bpy.ops.wm.tool_set_by_id(name="builtin.select") # Tweaktoolcode
 289     return cage
 290
 291
 292 def back_to_obj(obj, gp_mode, org_lattice_toolset, context):
 293     if context.mode == 'EDIT_LATTICE' and org_lattice_toolset: # Tweaktoolcode - restore the active tool used by lattice edit..
 294         bpy.ops.wm.tool_set_by_id(name = org_lattice_toolset) # Tweaktoolcode
 295
 296     # gp object active and selected
 297     bpy.ops.object.mode_set(mode='OBJECT')
 298     obj.select_set(True)
 299     bpy.context.view_layer.objects.active = obj
 300
 301
 302 def delete_cage(cage):
 303     lattice = cage.data
 304     bpy.data.objects.remove(cage)
 305     bpy.data.lattices.remove(lattice)
 306
 307 def apply_cage(gp_obj):
 308     mod = gp_obj.grease_pencil_modifiers.get('tmp_lattice')
 309     multi_user = None
 310     if mod:
 311         if gp_obj.data.users > 1:
 312             old = gp_obj.data
 313             multi_user = old.name
 314             other_user = [o for o in bpy.data.objects if o is not gp_obj and o.data is old]
 315             gp_obj.data = gp_obj.data.copy()
 316
 317         # bpy.ops.object.gpencil_modifier_apply(apply_as='DATA', modifier=mod.name)
 318         bpy.ops.object.gpencil_modifier_apply({'object': gp_obj}, apply_as='DATA', modifier=mod.name)
 319
 320         if multi_user:
 321             for o in other_user: # relink
 322                 o.data = gp_obj.data
 323             bpy.data.grease_pencils.remove(old)
 324             gp_obj.data.name = multi_user
 325
 326     else:
 327         print('tmp_lattice modifier not found to apply...')
 328
 329 def cancel_cage(self):
 330     #remove modifier
 331     mod = self.gp_obj.grease_pencil_modifiers.get('tmp_lattice')
 332     if mod:
 333         self.gp_obj.grease_pencil_modifiers.remove(mod)
 334     else:
 335         print(f'tmp_lattice modifier not found to remove on {self.gp_obj.name}')
 336
 337     for ob in self.other_gp:
 338         mod = ob.grease_pencil_modifiers.get('tmp_lattice')
 339         if mod:
 340             ob.grease_pencil_modifiers.remove(mod)
 341         else:
 342             print(f'tmp_lattice modifier not found to remove on {ob.name}')
 343
 344     delete_cage(self.cage)
 345
 346
 347 class GP_OT_latticeGpDeform(bpy.types.Operator):
 348     """Create a lattice to use as quad corner transform"""
 349     bl_idname = "gp.latticedeform"
 350     bl_label = "Box Deform"
 351     bl_description = "Use lattice for free box transforms on grease pencil points (Ctrl+T)"
 352     bl_options = {"REGISTER", "UNDO"}
 353
 354     @classmethod
 355     def poll(cls, context):
 356         return context.object is not None and context.object.type in ('GPENCIL','LATTICE')
 357
 358     # local variable
 359     tab_press_ct = 0
 360
 361     def modal(self, context, event):
 362         display_text = f"Deform Cage size: {self.lat.points_u}x{self.lat.points_v} (1-9 or ctrl + ←→↑↓)  | \
 363 mode (M) : {'Linear' if self.lat.interpolation_type_u == 'KEY_LINEAR' else 'Spline'} | \
 364 valid:Spacebar/Enter, cancel:Del/Backspace/Tab/Ctrl+T"
 365         context.area.header_text_set(display_text)
 366
 367
 368         ## Handle ctrl+Z
 369         if event.type in {'Z'} and event.value == 'PRESS' and event.ctrl:
 370             ## Disable (capture key)
 371             return {"RUNNING_MODAL"}
 372             ## Not found how possible to find modal start point in undo stack to
 373             # print('ops list', context.window_manager.operators.keys())
 374             # if context.window_manager.operators:#can be empty
 375             #     print('\nlast name', context.window_manager.operators[-1].name)
 376
 377         # Auto interpo check
 378         if self.auto_interp:
 379             if event.type in {'TWO', 'THREE', 'FOUR', 'FIVE', 'SIX', 'SEVEN', 'EIGHT', 'NINE', 'ZERO',} and event.value == 'PRESS':
 380                 self.set_lattice_interp('KEY_BSPLINE')
 381             if event.type in {'DOWN_ARROW', "UP_ARROW", "RIGHT_ARROW", "LEFT_ARROW"} and event.value == 'PRESS' and event.ctrl:
 382                 self.set_lattice_interp('KEY_BSPLINE')
 383             if event.type in {'ONE'} and event.value == 'PRESS':
 384                 self.set_lattice_interp('KEY_LINEAR')
 385
 386         # Single keys
 387         if event.type in {'H'} and event.value == 'PRESS':
 388             # self.report({'INFO'}, "Can't hide")
 389             return {"RUNNING_MODAL"}
 390
 391         if event.type in {'ONE'} and event.value == 'PRESS':# , 'NUMPAD_1'
 392             self.lat.points_u = self.lat.points_v = 2
 393             return {"RUNNING_MODAL"}
 394
 395         if event.type in {'TWO'} and event.value == 'PRESS':# , 'NUMPAD_2'
 396             self.lat.points_u = self.lat.points_v = 3
 397             return {"RUNNING_MODAL"}
 398
 399         if event.type in {'THREE'} and event.value == 'PRESS':# , 'NUMPAD_3'
 400             self.lat.points_u = self.lat.points_v = 4
 401             return {"RUNNING_MODAL"}
 402
 403         if event.type in {'FOUR'} and event.value == 'PRESS':# , 'NUMPAD_4'
 404             self.lat.points_u = self.lat.points_v = 5
 405             return {"RUNNING_MODAL"}
 406
 407         if event.type in {'FIVE'} and event.value == 'PRESS':# , 'NUMPAD_5'
 408             self.lat.points_u = self.lat.points_v = 6
 409             return {"RUNNING_MODAL"}
 410
 411         if event.type in {'SIX'} and event.value == 'PRESS':# , 'NUMPAD_6'
 412             self.lat.points_u = self.lat.points_v = 7
 413             return {"RUNNING_MODAL"}
 414
 415         if event.type in {'SEVEN'} and event.value == 'PRESS':# , 'NUMPAD_7'
 416             self.lat.points_u = self.lat.points_v = 8
 417             return {"RUNNING_MODAL"}
 418
 419         if event.type in {'EIGHT'} and event.value == 'PRESS':# , 'NUMPAD_8'
 420             self.lat.points_u = self.lat.points_v = 9
 421             return {"RUNNING_MODAL"}
 422
 423         if event.type in {'NINE'} and event.value == 'PRESS':# , 'NUMPAD_9'
 424             self.lat.points_u = self.lat.points_v = 10
 425             return {"RUNNING_MODAL"}
 426
 427         if event.type in {'ZERO'} and event.value == 'PRESS':# , 'NUMPAD_0'
 428             self.lat.points_u = 2
 429             self.lat.points_v = 1
 430             return {"RUNNING_MODAL"}
 431
 432         if event.type in {'RIGHT_ARROW'} and event.value == 'PRESS' and event.ctrl:
 433             if self.lat.points_u < 20:
 434                 self.lat.points_u += 1
 435             return {"RUNNING_MODAL"}
 436
 437         if event.type in {'LEFT_ARROW'} and event.value == 'PRESS' and event.ctrl:
 438             if self.lat.points_u > 1:
 439                 self.lat.points_u -= 1
 440             return {"RUNNING_MODAL"}
 441
 442         if event.type in {'UP_ARROW'} and event.value == 'PRESS' and event.ctrl:
 443             if self.lat.points_v < 20:
 444                 self.lat.points_v += 1
 445             return {"RUNNING_MODAL"}
 446
 447         if event.type in {'DOWN_ARROW'} and event.value == 'PRESS' and event.ctrl:
 448             if self.lat.points_v > 1:
 449                 self.lat.points_v -= 1
 450             return {"RUNNING_MODAL"}
 451
 452
 453         # change modes
 454         if event.type in {'M'} and event.value == 'PRESS':
 455             self.auto_interp = False
 456             interp = 'KEY_BSPLINE' if self.lat.interpolation_type_u == 'KEY_LINEAR' else 'KEY_LINEAR'
 457             self.set_lattice_interp(interp)
 458             return {"RUNNING_MODAL"}
 459
 460         # Valid
 461         if event.type in {'RET', 'SPACE', 'NUMPAD_ENTER'}:
 462             if event.value == 'PRESS':
 463                 context.window_manager.boxdeform_running = False
 464                 self.restore_prefs(context)
 465                 back_to_obj(self.gp_obj, self.gp_mode, self.org_lattice_toolset, context)
 466                 if event.shift:
 467                     # Let the cage as is with a unique ID
 468                     store_cage(self, 'lattice_cage_deform_group')
 469                 else:
 470                     apply_cage(self.gp_obj) # must be in object mode
 471                     assign_vg(self.gp_obj, 'lattice_cage_deform_group', delete=True)
 472                     for o in self.other_gp:
 473                         apply_cage(o)
 474                         assign_vg(o, 'lattice_cage_deform_group', delete=True)
 475                     delete_cage(self.cage)
 476
 477                 # back to original mode
 478                 if self.gp_mode != 'OBJECT':
 479                     bpy.ops.object.mode_set(mode=self.gp_mode)
 480                 context.area.header_text_set(None)#reset header
 481
 482                 return {'FINISHED'}
 483
 484         # Abort ---
 485         # One Warning for Tab cancellation.
 486         if event.type == 'TAB' and event.value == 'PRESS':
 487             self.tab_press_ct += 1
 488             if self.tab_press_ct < 2:
 489                 self.report({'WARNING'}, "Pressing TAB again will Cancel")
 490                 return {"RUNNING_MODAL"}
 491
 492         if event.type in {'T'} and event.value == 'PRESS' and event.ctrl:# Retyped same shortcut
 493             self.cancel(context)
 494             return {'CANCELLED'}
 495
 496         if event.type in {'DEL', 'BACK_SPACE'} or self.tab_press_ct >= 2:#'ESC',
 497             self.cancel(context)
 498             return {'CANCELLED'}
 499
 500         return {'PASS_THROUGH'}
 501
 502     def set_lattice_interp(self, interp):
 503         self.lat.interpolation_type_u = self.lat.interpolation_type_v = self.lat.interpolation_type_w = interp
 504
 505     def cancel(self, context):
 506         context.window_manager.boxdeform_running = False
 507         self.restore_prefs(context)
 508         back_to_obj(self.gp_obj, self.gp_mode, self.org_lattice_toolset, context)
 509         cancel_cage(self)
 510         assign_vg(self.gp_obj, 'lattice_cage_deform_group', delete=True)
 511         context.area.header_text_set(None)
 512         if self.gp_mode != 'OBJECT':
 513             bpy.ops.object.mode_set(mode=self.gp_mode)
 514
 515     def store_prefs(self, context):
 516         # store_valierables <-< preferences
 517         self.use_drag_immediately = context.preferences.inputs.use_drag_immediately
 518         self.drag_threshold_mouse = context.preferences.inputs.drag_threshold_mouse
 519         self.drag_threshold_tablet = context.preferences.inputs.drag_threshold_tablet
 520         self.use_overlays = context.space_data.overlay.show_overlays
 521         # maybe store in windows manager to keep around in case of modal revival ?
 522
 523     def restore_prefs(self, context):
 524         # preferences <-< store_valierables
 525         context.preferences.inputs.use_drag_immediately = self.use_drag_immediately
 526         context.preferences.inputs.drag_threshold_mouse = self.drag_threshold_mouse
 527         context.preferences.inputs.drag_threshold_tablet = self.drag_threshold_tablet
 528         context.space_data.overlay.show_overlays = self.use_overlays
 529
 530     def set_prefs(self, context):
 531         context.preferences.inputs.use_drag_immediately = True
 532         context.preferences.inputs.drag_threshold_mouse = 1
 533         context.preferences.inputs.drag_threshold_tablet = 3
 534         context.space_data.overlay.show_overlays = True
 535
 536     def invoke(self, context, event):
 537         ## Restrict to 3D view
 538         if context.area.type != 'VIEW_3D':
 539             self.report({'WARNING'}, "View3D not found, cannot run operator")
 540             return {'CANCELLED'}
 541
 542         if not context.object:#do it in poll ?
 543             self.report({'ERROR'}, "No active objects found")
 544             return {'CANCELLED'}
 545
 546         if context.window_manager.boxdeform_running:
 547             return {'CANCELLED'}
 548
 549         self.prefs = get_addon_prefs()#get_prefs
 550         self.auto_interp = self.prefs.auto_swap_deform_type
 551         self.org_lattice_toolset = None
 552         ## usability toggles
 553         if self.prefs.use_clic_drag:#Store the active tool since we will change it
 554             self.org_lattice_toolset = bpy.context.workspace.tools.from_space_view3d_mode(bpy.context.mode, create=False).idname# Tweaktoolcode
 555
 556         #store (scene properties needed in case of ctrlZ revival)
 557         self.store_prefs(context)
 558         self.gp_mode = 'EDIT_GPENCIL'
 559
 560         # --- special Case of lattice revive modal, just after ctrl+Z back into lattice with modal stopped
 561         if context.mode == 'EDIT_LATTICE' and context.object.name == 'lattice_cage_deform' and len(context.object.vertex_groups):
 562             self.gp_obj = context.scene.objects.get(context.object.vertex_groups[0].name)
 563             if not self.gp_obj:
 564                 self.report({'ERROR'}, "/!\\ Box Deform : Cannot find object to target")
 565                 return {'CANCELLED'}
 566             if not self.gp_obj.grease_pencil_modifiers.get('tmp_lattice'):
 567                 self.report({'ERROR'}, "/!\\ No 'tmp_lattice' modifiers on GP object")
 568                 return {'CANCELLED'}
 569             self.cage = context.object
 570             self.lat = self.cage.data
 571             self.set_prefs(context)
 572
 573             if self.prefs.use_clic_drag:
 574                 bpy.ops.wm.tool_set_by_id(name="builtin.select")
 575             context.window_manager.boxdeform_running = True
 576             context.window_manager.modal_handler_add(self)
 577             return {'RUNNING_MODAL'}
 578
 579         if context.object.type != 'GPENCIL':
 580             # self.report({'ERROR'}, "Works only on gpencil objects")
 581             ## silent return
 582             return {'CANCELLED'}
 583
 584         if context.mode not in ('EDIT_GPENCIL', 'OBJECT', 'PAINT_GPENCIL'):
 585             # self.report({'WARNING'}, "Works only in following GPencil modes: object / edit/ paint")# ERROR
 586             ## silent return
 587             return {'CANCELLED'}
 588
 589
 590         # bpy.ops.ed.undo_push(message="Box deform step")#don't work as expected (+ might be obsolete)
 591         # https://developer.blender.org/D6147 <- undo forget
 592
 593         self.gp_obj = context.object
 594
 595         self.from_object = context.mode == 'OBJECT'
 596         self.all_gps = self.other_gp = []
 597         if self.from_object:
 598             self.all_gps = [o for o in bpy.context.selected_objects if o.type == 'GPENCIL']
 599             self.other_gp = [o for o in self.all_gps if o is not self.gp_obj]
 600
 601         # Clean potential failed previous job (delete tmp lattice)
 602         mod = self.gp_obj.grease_pencil_modifiers.get('tmp_lattice')
 603         if mod:
 604             print('Deleted remaining lattice modifiers')
 605             self.gp_obj.grease_pencil_modifiers.remove(mod)
 606
 607         phantom_obj = context.scene.objects.get('lattice_cage_deform')
 608         if phantom_obj:
 609             print('Deleted remaining lattice object')
 610             delete_cage(phantom_obj)
 611
 612         if bpy.app.version < (2,93,0):
 613             if [m for m in self.gp_obj.grease_pencil_modifiers if m.type == 'GP_LATTICE']:
 614                 self.report({'ERROR'}, "Grease pencil object already has a lattice modifier (multi-lattices are enabled in blender 2.93+)")
 615                 return {'CANCELLED'}
 616
 617         self.gp_mode = context.mode # store mode for restore
 618
 619         # All good, create lattice and start modal
 620
 621         # Create lattice (and switch to lattice edit) ----
 622         self.cage = view_cage(self.gp_obj)
 623         if isinstance(self.cage, str):#error, cage not created, display error
 624             self.report({'ERROR'}, self.cage)
 625             return {'CANCELLED'}
 626
 627         self.lat = self.cage.data
 628
 629         self.set_prefs(context)
 630         context.window_manager.boxdeform_running = True
 631         context.window_manager.modal_handler_add(self)
 632         return {'RUNNING_MODAL'}
 633
 634 ## --- KEYMAP
 635
 636 addon_keymaps = []
 637 def register_keymaps():
 638     addon = bpy.context.window_manager.keyconfigs.addon
 639
 640     km = addon.keymaps.new(name = "Grease Pencil", space_type = "EMPTY", region_type='WINDOW')
 641     kmi = km.keymap_items.new("gp.latticedeform", type ='T', value = "PRESS", ctrl = True)
 642     kmi.repeat = False
 643     addon_keymaps.append((km, kmi))
 644
 645 def unregister_keymaps():
 646     for km, kmi in addon_keymaps:
 647         km.keymap_items.remove(kmi)
 648     addon_keymaps.clear()
 649
 650 ### --- REGISTER ---
 651
 652 def register():
 653     if bpy.app.background:
 654         return
 655     bpy.types.WindowManager.boxdeform_running = bpy.props.BoolProperty(default=False)
 656     bpy.utils.register_class(GP_OT_latticeGpDeform)
 657     register_keymaps()
 658
 659 def unregister():
 660     if bpy.app.background:
 661         return
 662     unregister_keymaps()
 663     bpy.utils.unregister_class(GP_OT_latticeGpDeform)
 664     wm = bpy.context.window_manager
 665     p = 'boxdeform_running'
 666     if p in wm:
 667         del wm[p]