power_sequencer/operators/crossfade_edit.py

   1 # SPDX-FileCopyrightText: 2016-2020 by Nathan Lovato, Daniel Oakey, Razvan Radulescu, and contributors
   2 #
   3 # SPDX-License-Identifier: GPL-3.0-or-later
   4
   5 import bpy
   6
   7 from .utils.global_settings import SequenceTypes
   8 from .utils.doc import doc_name, doc_idname, doc_brief, doc_description
   9
  10
  11 class POWER_SEQUENCER_OT_crossfade_edit(bpy.types.Operator):
  12     """
  13     *brief* Adjust the location of the crossfade between 2 strips
  14
  15
  16     Selects the handles of both inputs of a crossfade strip's input and
  17     calls the grab operator. Allows you to quickly change the location
  18     of a fade transition between two strips.
  19     """
  20
  21     doc = {
  22         "name": doc_name(__qualname__),
  23         "demo": "https://i.imgur.com/rCmLhg6.gif",
  24         "description": doc_description(__doc__),
  25         "shortcuts": [],
  26         "keymap": "Sequencer",
  27     }
  28     bl_idname = doc_idname(__qualname__)
  29     bl_label = doc["name"]
  30     bl_description = doc_brief(doc["description"])
  31     bl_options = {"REGISTER", "UNDO"}
  32
  33     crossfade_types = ["CROSS", "GAMMA_CROSS"]
  34
  35     @classmethod
  36     def poll(cls, context):
  37         return context.scene.sequence_editor.active_strip and context.selected_sequences
  38
  39     def execute(self, context):
  40         active = context.scene.sequence_editor.active_strip
  41         if active.type not in self.crossfade_types:
  42             effect = self.find_cross_effect(context, active)
  43             if not effect:
  44                 return {"CANCELLED"}
  45             active = context.scene.sequence_editor.active_strip = effect
  46
  47         bpy.ops.sequencer.select_all(action="DESELECT")
  48         active.select = True
  49         active.input_1.select_right_handle = True
  50         active.input_2.select_left_handle = True
  51         active.input_1.select = True
  52         active.input_2.select = True
  53         bpy.ops.transform.seq_slide("INVOKE_DEFAULT")
  54         return {"FINISHED"}
  55
  56     def find_cross_effect(self, sequence):
  57         """
  58         Takes a single strip and finds effect strips that use it as input
  59         Returns the effect strip(s) found as a list, ordered by starting frame
  60         Returns None if no effect was found
  61         """
  62         if sequence.type not in SequenceTypes.VIDEO + SequenceTypes.IMAGE:
  63             return
  64
  65         effect_sequences = (s for s in context.sequences if s.type in SequenceTypes.EFFECT)
  66         found_effect_strips = []
  67         for s in effect_sequences:
  68             if s.input_1.name == sequence.name:
  69                 found_effect_strips.append(s)
  70             if s.input_count == 2:
  71                 if s.input_2.name == sequence.name:
  72                     found_effect_strips.append(s)
  73         for e in found_effect_strips:
  74             if e.type not in self.crossfade_types:
  75                 continue
  76             return e