add step select gp frames feature

2.5.0

- added: Animation manager new button `Frame Select Step` (sort of a checker deselect, but in GP dopesheet)

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+2.5.0
+
+- added: Animation manager new button `Frame Select Step` (sort of a checker deselect, but in GP dopesheet)
+
 2.4.0
 
 - changed: Batch reproject consider camera movement and is almost 8x faster

OP_helpers.py

@@ -1,15 +1,17 @@
-from time import ctime
 import bpy
 import mathutils
-from mathutils import Vector#, Matrix
-from pathlib import Path
 import math
+
+from time import ctime
+from mathutils import Vector #, Matrix
+from pathlib import Path
 from math import radians
+from bpy.types import Operator
+
 from .view3d_utils import View3D
 from . import utils
 
-
+class GPTB_OT_copy_text(Operator):
-class GPTB_OT_copy_text(bpy.types.Operator):
     bl_idname = "wm.copytext"
     bl_label = "Copy To Clipboard"
     bl_description = "Insert passed text to clipboard"
@@ -23,7 +25,7 @@ class GPTB_OT_copy_text(bpy.types.Operator):
         self.report({'INFO'}, mess)
         return {"FINISHED"}
 
-class GPTB_OT_flipx_view(bpy.types.Operator):
+class GPTB_OT_flipx_view(Operator):
     bl_idname = "view3d.camera_mirror_flipx"
     bl_label = "Cam Mirror Flipx"
     bl_description = "Invert X scale on camera to flip image horizontally"
@@ -38,7 +40,7 @@ class GPTB_OT_flipx_view(bpy.types.Operator):
         context.scene.camera.scale.x *= -1
         return {"FINISHED"}
 
-class GPTB_OT_view_camera_frame_fit(bpy.types.Operator):
+class GPTB_OT_view_camera_frame_fit(Operator):
     bl_idname = "view3d.view_camera_frame_fit"
     bl_label = "View Fit"
     bl_description = "Fit the camera in view (view 1:1)"
@@ -67,7 +69,7 @@ class GPTB_OT_view_camera_frame_fit(bpy.types.Operator):
 
         return {"FINISHED"}
 
-class GPTB_OT_rename_data_from_obj(bpy.types.Operator):
+class GPTB_OT_rename_data_from_obj(Operator):
     bl_idname = "gp.rename_data_from_obj"
     bl_label = "Rename GP From Object"
     bl_description = "Rename the GP datablock with the same name as the object"
@@ -148,7 +150,7 @@ def get_gp_alignement_vector(context):
     elif orient == 'CURSOR':
         return Vector((0,0,1))#.rotate(context.scene.cursor.matrix)
 
-class GPTB_OT_draw_cam(bpy.types.Operator):
+class GPTB_OT_draw_cam(Operator):
     bl_idname = "gp.draw_cam_switch"
     bl_label = "Draw Cam Switch"
     bl_description = "switch between main camera and draw (manipulate) camera"
@@ -276,7 +278,7 @@ class GPTB_OT_draw_cam(bpy.types.Operator):
         return {"FINISHED"}
 
 
-class GPTB_OT_set_view_as_cam(bpy.types.Operator):
+class GPTB_OT_set_view_as_cam(Operator):
     bl_idname = "gp.set_view_as_cam"
     bl_label = "Cam At View"
     bl_description = "Place the active camera at current viewpoint, parent to active object. (need to be out of camera)"
@@ -318,7 +320,7 @@ class GPTB_OT_set_view_as_cam(bpy.types.Operator):
         return {"FINISHED"}
 
 
-class GPTB_OT_reset_cam_rot(bpy.types.Operator):
+class GPTB_OT_reset_cam_rot(Operator):
     bl_idname = "gp.reset_cam_rot"
     bl_label = "Reset Rotation"
     bl_description = "Reset rotation of the draw manipulation camera"
@@ -396,7 +398,7 @@ class GPTB_OT_reset_cam_rot(bpy.types.Operator):
         context.space_data.region_3d.view_camera_offset = new_cam_offset
         return {"FINISHED"}
 
-class GPTB_OT_toggle_mute_animation(bpy.types.Operator):
+class GPTB_OT_toggle_mute_animation(Operator):
     bl_idname = "gp.toggle_mute_animation"
     bl_label = "Toggle Animation Mute"
     bl_description = "Enable/Disable animation evaluation\n(shift+clic to affect selection only)"
@@ -451,7 +453,7 @@ class GPTB_OT_toggle_mute_animation(bpy.types.Operator):
 
         return {'FINISHED'}
 
-class GPTB_OT_toggle_hide_gp_modifier(bpy.types.Operator):
+class GPTB_OT_toggle_hide_gp_modifier(Operator):
     bl_idname = "gp.toggle_hide_gp_modifier"
     bl_label = "Toggle Modifier Hide"
     bl_description = "Show/Hide viewport on GP objects modifier\
@@ -481,7 +483,7 @@ class GPTB_OT_toggle_hide_gp_modifier(bpy.types.Operator):
 
         return {'FINISHED'}
 
-class GPTB_OT_list_disabled_anims(bpy.types.Operator):
+class GPTB_OT_list_disabled_anims(Operator):
     bl_idname = "gp.list_disabled_anims"
     bl_label = "List Disabled Anims"
     bl_description = "List disabled animations channels in scene. (shit+clic to list only on seleciton)"
@@ -546,7 +548,7 @@ class GPTB_OT_list_disabled_anims(bpy.types.Operator):
 
 ## TODO presets are still not used... need to make a custom preset save/remove/quickload manager to be efficient (UIlist ?)
 
-class GPTB_OT_overlay_presets(bpy.types.Operator):
+class GPTB_OT_overlay_presets(Operator):
     bl_idname = "gp.overlay_presets"
     bl_label = "Overlay presets"
     bl_description = "Overlay save/load presets for showing only whats needed"
@@ -601,7 +603,7 @@ class GPTB_OT_overlay_presets(bpy.types.Operator):
         
         return {'FINISHED'}
 
-class GPTB_OT_clear_active_frame(bpy.types.Operator):
+class GPTB_OT_clear_active_frame(Operator):
     bl_idname = "gp.clear_active_frame"
     bl_label = "Clear Active Frame"
     bl_description = "Delete all strokes in active frames"
@@ -633,7 +635,7 @@ class GPTB_OT_clear_active_frame(bpy.types.Operator):
         
         return {'FINISHED'}
 
-class GPTB_OT_check_canvas_alignement(bpy.types.Operator):
+class GPTB_OT_check_canvas_alignement(Operator):
     bl_idname = "gp.check_canvas_alignement"
     bl_label = "Check Canvas Alignement"
     bl_description = "Check if view is aligned to canvas\nWarn if the drawing angle to surface is too high\nThere can be some error margin"
@@ -663,7 +665,116 @@ class GPTB_OT_check_canvas_alignement(bpy.types.Operator):
         # self.report({ret}, message)
         return {'FINISHED'}
 
-class GPTB_OT_open_addon_prefs(bpy.types.Operator):
+class GPTB_OT_step_select_frames(Operator):
+    bl_idname = "gptb.step_select_frames"
+    bl_label = "Step Select Frame"
+    bl_description = "Select frames by a step frame value"
+    bl_options = {"REGISTER", "UNDO"}
+
+    @classmethod
+    def poll(cls, context):
+        return context.object and context.object.type == 'GPENCIL'
+
+    start : bpy.props.IntProperty(name='Start Frame',
+                                  description='Start frame of the step animation',
+                                  default=100)
+    
+    step : bpy.props.IntProperty(name='Step',
+                                  description='Step of the frame, value of 2 select one frame on two',
+                                  default=2,
+                                  min=2)
+
+    strict : bpy.props.BoolProperty(name='Strict',
+                                  description='Strictly select step frame from start to scene end range\
+                                    \nElse reset step when a gap exsits already',
+                                  default=False)
+
+    # TODO: add option to start at cursor (True default)
+
+    def invoke(self, context, execute):
+                ## list frame to keep
+        return context.window_manager.invoke_props_dialog(self, width=450)
+        # return self.execute(context)
+
+    def draw(self, context):
+        layout = self.layout
+        col = layout.column()
+        col.prop(self, 'step')
+
+        col.prop(self, 'strict')
+        if self.strict:
+            col.prop(self, 'start')
+        
+        ## helper (need more work)
+        # col.separator()
+        # range_string = f"{', '.join(numbers[:3])} ... {', '.join(numbers[-3:])}"
+        # col.label(text=f'Will keep {range_string}')
+        if not self.strict:
+            col.label(text=f'Each gap will be considered a new step start', icon='INFO')
+
+    def execute(self, context):
+        numbers = [i for i in range(self.start, context.scene.frame_end + 1, self.step)]
+        self.to_select = numbers
+
+        ## Negative switch : list frames to remove
+        self.to_select = [i for i in range(self.start, context.scene.frame_end + 1) if i not in numbers]
+
+        gp = context.object.data
+        
+        ## Get frame summary (reset start after each existing gaps)
+        key_summary = list(set([f.frame_number for l in gp.layers for f in l.frames]))
+        key_summary.sort()
+        print('key summary: ', key_summary)
+
+        start = key_summary[0]
+        if self.strict:
+            to_select = self.to_select
+        else:
+            to_select = []
+            prev = None
+            for k in key_summary:
+                print(k, prev)
+                if prev is not None and k != prev + 1:
+                    ## this is a gap ! new start
+                    prev = start = k
+                    # print('new start', start)
+                    continue
+                
+                new_range = [i for i in range(start, key_summary[-1] + 1, self.step)]
+                # print('new_range: ', new_range)
+                if k not in new_range:
+                    to_select.append(k)
+
+                prev = k
+
+        ## deselect all
+        for l in gp.layers:
+            for f in l.frames:
+                f.select = False
+
+        print('To select:', to_select)
+        gct = 0
+        for i in to_select:
+            ct = 0
+            for l in gp.layers:
+                frame = next((f for f in l.frames if f.frame_number == i), None)
+                if not frame:
+                    continue
+
+                ## Select instead of remove
+                frame.select = True
+                ## Optionnally remove frames ?
+                # l.frames.remove(frame)
+
+                ct += 1
+            
+            # print(f'{i}: Selected {ct} frame(s)')
+            gct += ct
+
+        self.report({'INFO'}, f'Selected {gct} frames')
+        return {"FINISHED"}
+
+class GPTB_OT_open_addon_prefs(Operator):
     bl_idname = "gptb.open_addon_prefs"
     bl_label = "Open Addon Prefs"
     bl_description = "Open user preferences window in addon tab and prefill the search with addon name"
@@ -686,6 +797,7 @@ GPTB_OT_toggle_hide_gp_modifier,
 GPTB_OT_list_disabled_anims,
 GPTB_OT_clear_active_frame,
 GPTB_OT_check_canvas_alignement,
+GPTB_OT_step_select_frames,
 GPTB_OT_open_addon_prefs,
 )
 

UI_tools.py

@@ -242,6 +242,9 @@ class GPTB_PT_anim_manager(Panel):
         row.operator('gp.toggle_hide_gp_modifier', text='ON', icon=on_icon).show = True
         row.operator('gp.toggle_hide_gp_modifier', text='OFF', icon=off_icon).show = False
 
+        ## Step Select Frames
+        col.operator('gptb.step_select_frames')
+
         ## Follow curve path
         col = col.column()
         row = col.row(align=True)

__init__.py

@@ -4,7 +4,7 @@ bl_info = {
 "name": "GP toolbox",
 "description": "Tool set for Grease Pencil in animation production",
 "author": "Samuel Bernou, Christophe Seux",
-"version": (2, 4, 0),
+"version": (2, 5, 0),
 "blender": (3, 0, 0),
 "location": "Sidebar (N menu) > Gpencil > Toolbox / Gpencil properties",
 "warning": "",