Files
test/scripts/startup/bl_ui/properties_animviz.py
Christoph Lendenfeld 79f84775f2 Anim: Motion Paths in camera space
Animators (especially for film and TV) often need
to track the movement of things in screenspace.
At the end of the day, the pixel motion is what counts.
But motion paths were always in world space,
which made it hard to use when the camera
is also animated (during action scenes e.g.)

This PR introduces the feature of projecting a motion path into the screen space of the active scene camera.

Limitations
This makes the motion path only useful when looking through the active scene camera.
Switching the scene camera using markers is not yet supported.

Technical Implementation
This is achieved by baking the motion path points into the
camera space on creation. For every point calculated,
the camera is evaluated through the depsgraph and
the resulting world matrix is used.
Then I pass in the current frame's world matrix of the
camera into the shader to make sure the points follow it.
As can be seen in the video, it looks quite odd when
viewed at another angle but this is expected.
I mentioned that in the tooltip, so it shouldn't be an issue

Pull Request: https://projects.blender.org/blender/blender/pulls/117593
2024-02-06 23:14:17 +01:00

125 lines
4.3 KiB
Python

# SPDX-FileCopyrightText: 2010-2023 Blender Authors
#
# SPDX-License-Identifier: GPL-2.0-or-later
# Generic Panels (Independent of DataType)
# NOTE:
# The specialized panel types are derived in their respective UI modules
# don't register these classes since they are only helpers.
class MotionPathButtonsPanel:
bl_space_type = 'PROPERTIES'
bl_region_type = 'WINDOW'
bl_label = "Motion Paths"
# bl_options = {'DEFAULT_CLOSED'}
def draw_settings(self, _context, avs, mpath, bones=False):
layout = self.layout
mps = avs.motion_path
layout.use_property_split = True
layout.use_property_decorate = False
col = layout.column(align=True)
col.prop(mps, "type")
range_group = col.column(align=True)
range_group.active = mps.type == 'RANGE'
range_group.prop(mps, "range", text="Calculation Range")
if mps.type == 'CURRENT_FRAME':
col = layout.column(align=True)
col.prop(mps, "frame_before", text="Frame Range Before")
col.prop(mps, "frame_after", text="After")
col.prop(mps, "frame_step", text="Step")
elif mps.type == 'RANGE':
col = layout.column(align=True)
start_end_group = col.column(align=True)
start_end_group.active = mps.range == 'MANUAL'
start_end_group.prop(mps, "frame_start", text="Frame Range Start")
start_end_group.prop(mps, "frame_end", text="End")
col.prop(mps, "frame_step", text="Step")
row = col.row()
row.prop(mps, "bake_in_camera_space", text="Bake to Active Camera")
if bones:
op_category = "pose"
icon = 'BONE_DATA'
else:
op_category = "object"
icon = 'OBJECT_DATA'
if mpath:
col = layout.column(align=True)
row = col.row(align=True)
row.enabled = False
row.prop(mpath, "frame_start", text="Cached Range")
row.prop(mpath, "frame_end", text="")
# Update Selected.
col = layout.column(align=True)
row = col.row(align=True)
row.operator(op_category + ".paths_update", text="Update Path", icon=icon)
row.operator(op_category + ".paths_clear", text="", icon='X').only_selected = True
else:
# Calculate.
col = layout.column(align=True)
col.label(text="Nothing to show yet...", icon='ERROR')
col.operator(op_category + ".paths_calculate", text="Calculate...", icon=icon)
# Update All & Clear All.
# Note that `col` is from inside the preceding `if` or `else` block.
row = col.row(align=True)
row.operator("object.paths_update_visible", text="Update All Paths", icon='WORLD')
row.operator(op_category + ".paths_clear", text="", icon='X').only_selected = False
class MotionPathButtonsPanel_display:
bl_space_type = 'PROPERTIES'
bl_region_type = 'WINDOW'
bl_label = "Display"
def draw_settings(self, _context, avs, mpath, bones=False):
layout = self.layout
mps = avs.motion_path
layout.use_property_split = True
layout.use_property_decorate = False
flow = layout.grid_flow(row_major=False, columns=0, even_columns=False, even_rows=False, align=True)
flow.prop(mps, "show_frame_numbers", text="Frame Numbers")
flow.prop(mps, "show_keyframe_highlight", text="Keyframes")
sub = flow.column()
sub.enabled = mps.show_keyframe_highlight
if bones:
sub.prop(mps, "show_keyframe_action_all", text="+ Non-Grouped Keyframes")
sub.prop(mps, "show_keyframe_numbers", text="Keyframe Numbers")
# Customize path
if mpath is not None:
flow.prop(mpath, "lines", text="Lines")
col = layout.column()
col.prop(mpath, "line_thickness", text="Thickness")
split = col.split(factor=0.6)
split.prop(mpath, "use_custom_color", text="Custom Color")
sub = split.column()
sub.enabled = mpath.use_custom_color
sub.prop(mpath, "color", text="")
classes = (
)
if __name__ == "__main__": # only for live edit.
from bpy.utils import register_class
for cls in classes:
register_class(cls)