power_sequencer/operators/swap_strips.py

   1 #
   2 # Copyright (C) 2016-2019 by Nathan Lovato, Daniel Oakey, Razvan Radulescu, and contributors
   3 #
   4 # This file is part of Power Sequencer.
   5 #
   6 # Power Sequencer is free software: you can redistribute it and/or modify it under the terms of the
   7 # GNU General Public License as published by the Free Software Foundation, either version 3 of the
   8 # License, or (at your option) any later version.
   9 #
  10 # Power Sequencer is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  11 # without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License along with Power Sequencer. If
  15 # not, see <https://www.gnu.org/licenses/>.
  16 #
  17 import bpy
  18 from operator import attrgetter
  19
  20 from .utils.doc import doc_name, doc_idname, doc_brief, doc_description
  21
  22
  23 class POWER_SEQUENCER_OT_swap_strips(bpy.types.Operator):
  24     """
  25     *brief* Swaps the 2 strips between them
  26
  27
  28     Places the first strip in the channel and starting frame (frame_final_start) of the second
  29     strip, and places the second strip in the channel and starting frame (frame_final_end) of
  30     the first strip.  If there is no space for the swap, it does nothing.
  31     """
  32
  33     doc = {
  34         "name": doc_name(__qualname__),
  35         "demo": "",
  36         "description": doc_description(__doc__),
  37         "shortcuts": [],
  38         "keymap": "Sequencer",
  39     }
  40     bl_idname = doc_idname(__qualname__)
  41     bl_label = doc["name"]
  42     bl_description = doc_brief(doc["description"])
  43     bl_options = {"REGISTER", "UNDO"}
  44
  45     direction: bpy.props.EnumProperty(
  46         name="Direction",
  47         description="The direction to find the closest strip",
  48         items=[
  49             ("up", "Up", "The direction up from the selected strip"),
  50             ("down", "Down", "The direction down from the selected strip"),
  51         ],
  52         default="up",
  53     )
  54
  55     @classmethod
  56     def poll(cls, context):
  57         return context.selected_sequences
  58
  59     def execute(self, context):
  60         strip_1 = context.selected_sequences[0]
  61         if len(context.selected_sequences) == 1:
  62             strip_2 = self.find_closest_strip_vertical(context, strip_1, self.direction)
  63         else:
  64             strip_2 = context.selected_sequences[1]
  65         if not strip_2 or strip_1.lock or strip_2.lock:
  66             return {"CANCELLED"}
  67
  68         # Swap a strip and one of its effects
  69         if hasattr(strip_1, "input_1") or hasattr(strip_2, "input_1"):
  70             if not self.are_linked(strip_1, strip_2):
  71                 return {"CANCELLED"}
  72             self.swap_with_effect(strip_1, strip_2)
  73             return {"FINISHED"}
  74
  75         s1_start, s1_channel = strip_1.frame_final_start, strip_1.channel
  76         s2_start, s2_channel = strip_2.frame_final_start, strip_2.channel
  77
  78         self.move_to_end(strip_1, context)
  79         self.move_to_end(strip_2, context)
  80
  81         s1_start_2 = strip_1.frame_final_start
  82         s2_start_2 = strip_2.frame_final_start
  83
  84         group_1 = {
  85             s: s.channel
  86             for s in context.sequences
  87             if s.frame_final_start == s1_start_2 and s != strip_1
  88         }
  89         group_2 = {
  90             s: s.channel
  91             for s in context.sequences
  92             if s.frame_final_start == s2_start_2 and s != strip_2
  93         }
  94
  95         strip_2.select = False
  96         bpy.ops.transform.seq_slide(
  97             value=(s2_start - strip_1.frame_final_start, s2_channel - strip_1.channel)
  98         )
  99
 100         bpy.ops.sequencer.select_all(action="DESELECT")
 101         strip_2.select = True
 102         bpy.ops.transform.seq_slide(
 103             value=(s1_start - strip_2.frame_final_start, s1_channel - strip_2.channel)
 104         )
 105
 106         if not self.fits(
 107             strip_1, group_1, s2_start, s1_channel, s2_channel, context
 108         ) or not self.fits(strip_2, group_2, s1_start, s2_channel, s1_channel, context):
 109             self.reconstruct(strip_1, s1_channel, group_1, context)
 110             self.reconstruct(strip_2, s2_channel, group_2, context)
 111
 112             bpy.ops.sequencer.select_all(action="DESELECT")
 113             strip_1.select = True
 114             bpy.ops.transform.seq_slide(
 115                 value=(s1_start - strip_1.frame_final_start, s1_channel - strip_1.channel)
 116             )
 117
 118             bpy.ops.sequencer.select_all(action="DESELECT")
 119             strip_2.select = True
 120             bpy.ops.transform.seq_slide(
 121                 value=(s2_start - strip_2.frame_final_start, s2_channel - strip_2.channel)
 122             )
 123
 124             bpy.ops.sequencer.select_all(action="DESELECT")
 125             strip_1.select = True
 126             strip_2.select = True
 127             return {"CANCELLED"}
 128
 129         bpy.ops.sequencer.select_all(action="DESELECT")
 130         strip_1.select = True
 131         strip_2.select = True
 132         return {"FINISHED"}
 133
 134     def move_to_frame(self, strip, frame, context):
 135         """
 136         Moves a strip based on its frame_final_start without changing its
 137         duration.
 138         Args:
 139         - strip: The strip to be moved.
 140         - frame: The frame, the frame_final_start of the strip will be placed
 141                  at.
 142         """
 143         selected_strips = context.selected_sequences
 144         bpy.ops.sequencer.select_all(action="DESELECT")
 145         strip.select = True
 146
 147         bpy.ops.transform.seq_slide(value=(frame - strip.frame_final_start, 0))
 148
 149         bpy.ops.sequencer.select_all(action="DESELECT")
 150         for s in selected_strips:
 151             s.select = True
 152
 153     def move_to_end(self, strip, context):
 154         """
 155         Moves a strip to an empty slot at the end of the sequencer, different
 156         than its initial slot.
 157         Args:
 158         - strip: The strip to move.
 159         """
 160         end_frame = max(context.sequences, key=attrgetter("frame_final_end")).frame_final_end
 161         self.move_to_frame(strip, end_frame, context)
 162
 163     def fits(self, strip, group, frame, init_channel, target_channel, context):
 164         """
 165         Checks if a swap has been successful or not.
 166         Args:
 167         - strip: The core strip of the swap.
 168         - group: The effect strips of the core strip.
 169         - frame: The starting frame of the target location.
 170         - init_channel: The initial channel of the strip, before the swap took
 171                         place.
 172         - target_channel: The channel of the target location.
 173         Returns: True if the swap was successful, otherwise False.
 174         """
 175         if strip.frame_final_start != frame or strip.channel != target_channel:
 176             return False
 177
 178         offset = strip.channel - init_channel
 179         for s in group.keys():
 180             if s.channel != group[s] + offset:
 181                 return False
 182
 183         return context.selected_sequences
 184
 185     def reconstruct(self, strip, init_channel, group, context):
 186         """
 187         Reconstructs a failed swap, based on a core strip. After its done, the
 188         core strip is placed at the end of the sequencer, in an empty slot.
 189         Args:
 190         - strip: The core strip of the swap.
 191         - init_channel: The initial channel of the core strip.
 192         - group: A dictionary with the effect strips of the core strip, and
 193                  their target channels.
 194         """
 195         self.move_to_end(strip, context)
 196         bpy.ops.sequencer.select_all(action="DESELECT")
 197         strip.select = True
 198         bpy.ops.transform.seq_slide(value=(0, init_channel - strip.channel))
 199
 200         for s in group.keys():
 201             channel = group[s]
 202             for u in group.keys():
 203                 if u.channel == channel and u != s:
 204                     u.channel += 1
 205             s.channel = channel
 206
 207     def find_closest_strip_vertical(self, context, strip, direction):
 208         """
 209         Finds the closest strip to a given strip in a specific direction.
 210         Args:
 211         - strip: The base strip.
 212         Returns: The closest strip to the given strip, in the proper direction.
 213                  If no strip is found, returns None.
 214         """
 215         strips_in_range = (
 216             s
 217             for s in context.sequences
 218             if strip.frame_final_start <= s.frame_final_start
 219             and s.frame_final_end <= strip.frame_final_end
 220         )
 221         if direction == "up":
 222             strips_above = [s for s in strips_in_range if s.channel > strip.channel]
 223             if not strips_above:
 224                 return
 225             return min(strips_above, key=attrgetter("channel"))
 226         elif direction == "down":
 227             strips_below = [s for s in strips_in_range if s.channel < strip.channel]
 228             if not strips_below:
 229                 return
 230             return max(strips_below, key=attrgetter("channel"))
 231
 232         def are_linked(self, strip_1, strip_2):
 233             return (
 234                 strip_1.frame_final_start == strip_2.frame_final_start
 235                 and strip_1.frame_final_end == strip_2.frame_final_end
 236             )
 237
 238         def swap_with_effect(self, strip_1, strip_2):
 239             effect_strip = strip_1 if hasattr(strip_1, "input_1") else strip_2
 240             other_strip = strip_1 if effect_strip != strip_1 else strip_2
 241
 242             effect_strip_channel = effect_strip.channel
 243             other_strip_channel = other_strip.channel
 244
 245             effect_strip.channel -= 1
 246             other_strip.channel = effect_strip_channel
 247             effect_strip.channel = other_strip_channel