Beispiel #1
0
def encode_vmd_boneframe(nice: List[vmdstruct.VmdBoneFrame],
                         moreinfo: bool) -> bytearray:
    output = bytearray()
    #############################
    # bone frames
    # first, the number of frames
    if moreinfo:
        core.MY_PRINT_FUNC("...# of boneframes          = %d" % len(nice))
    output += core.my_pack(fmt_number, len(nice))
    # then, all the actual frames
    for i, frame in enumerate(nice):
        # assemble the boneframe
        # first, gotta convert from euler to quaternion!
        euler = frame.rot  # x y z
        (w, x, y, z) = core.euler_to_quaternion(euler)  # w x y z
        quat = [x, y, z, w]  # x y z w
        # then, do the part that isn't the interpolation curve (first 9 values in binary, 8 things in frame), save as frame
        try:
            # now encode/pack/append the non-interp, non-phys portion
            packme = [frame.name, frame.f, *frame.pos, *quat]
            # packme.extend(frame.pos)
            # packme.extend(quat)
            output += core.my_pack(fmt_boneframe_no_interpcurve, packme)
            # then, create one line of the interpolation curve (last 16 values of frame obj)
            interp = core.my_pack(fmt_boneframe_interpcurve_oneline,
                                  frame.interp)
        except Exception as e:
            core.MY_PRINT_FUNC(e.__class__.__name__, e)
            core.MY_PRINT_FUNC("line=", i)
            core.MY_PRINT_FUNC("section=boneframe")
            core.MY_PRINT_FUNC(
                "Err: something went wrong while synthesizing binary output, probably the wrong type/order of values on a line"
            )
            raise RuntimeError()
        # do the dumb copy-and-shift thing to rebuild the original 4-line structure of redundant bytes
        interp += interp[1:] + bytes(1) + interp[2:] + bytes(
            2) + interp[3:] + bytes(3)
        # now overwrite the odd missing bytes with physics enable/disable data
        if frame.phys_off is True:
            interp[2] = 99
            interp[3] = 15
        else:
            interp[2] = 0
            interp[3] = 0
        # append the interpolation data onto the real output
        output += interp
        # progress thing just because
        core.print_progress_oneline(ENCODE_PERCENT_BONE * i / len(nice))

    return output
Beispiel #2
0
def write_vpd(vpd_filepath: str, vmd: vmdstruct.Vmd, moreinfo=False):
    """
	Grab all bone/morph frames at time=0 in a VMD object and write them to a properly-formatted VPD text file.
	
	:param vpd_filepath: destination filepath/name, relative from CWD or absolute
	:param vmd: input VMD object
	:param moreinfo: if true, get extra printouts with more info about stuff
	"""
    cleanname = core.get_clean_basename(vpd_filepath) + ".vpd"
    core.MY_PRINT_FUNC("Begin writing VPD file '%s'" % cleanname)

    # first, lets partition boneframes & morphframes into those at/notat time=0
    pose_bones, otherbones = core.my_list_partition(vmd.boneframes,
                                                    lambda b: b.f == 0)
    pose_morphs, othermorphs = core.my_list_partition(vmd.morphframes,
                                                      lambda b: b.f == 0)

    # if there are frames not on time=0, raise a warning but continue
    if otherbones or othermorphs:
        core.MY_PRINT_FUNC(
            "Warning: input VMD contains %d frames not at time=0, these will not be captured in the resulting pose!"
            % (len(otherbones) + len(othermorphs)))

    if moreinfo:
        core.MY_PRINT_FUNC("...model name   = JP:'%s'" % vmd.header.modelname)
    # init printlist with magic header, title, and numbones
    printlist = [
        "Vocaloid Pose Data file",
        "",
        "{:s}.osm;".format(vmd.header.modelname),
        "{:d};".format(len(pose_bones)),
        "",
    ]

    # now iterate over all bones
    # bone-floats always have exactly 6 digits
    if moreinfo:
        core.MY_PRINT_FUNC("...# of boneframes          = %d" %
                           len(pose_bones))
    for d, pb in enumerate(pose_bones):
        quat = list(core.euler_to_quaternion(pb.rot))  # returns quat WXYZ
        quat.append(quat.pop(0))  # WXYZ -> XYZW, AKA move head (w) to tail
        newitem = [
            "Bone{:d}{{{:s}".format(d, pb.name),
            "  {:.6f},{:.6f},{:.6f};".format(*pb.pos),
            "  {:.6f},{:.6f},{:.6f},{:.6f};".format(*quat),
            "}",
            "",
        ]
        printlist.extend(newitem)

    # now iterate over all morphs
    # morph-floats are flexible, need to TEST how long they can be!
    # lets say max precision is 3, but strip any trailing zeros and reduce "1." to "1"
    if moreinfo:
        core.MY_PRINT_FUNC("...# of morphframes         = %d" %
                           len(pose_morphs))
    for d, pm in enumerate(pose_morphs):
        newitem = [
            "Morph{:d}{{{:s}".format(d, pm.name),
            "  {:.3f}".format(pm.val).rstrip("0").rstrip(".") + ";", "}", ""
        ]
        printlist.extend(newitem)

    # ok, now i'm done building the printlist! now actually write it!
    core.write_list_to_txtfile(vpd_filepath, printlist, use_jis_encoding=True)
    core.MY_PRINT_FUNC("Done writing VPD file '%s'" % cleanname)

    return None
Beispiel #3
0
def rotation_calculate_ideal_bezier_slope(
        A: Optional[Tuple[int, Sequence[float]]], B: Tuple[int,
                                                           Sequence[float]],
        C: Optional[Tuple[int, Sequence[float]]]) -> Tuple[float, float]:
    """
	Calculate the ideal bezier slope for rotation interpolation curve. There is
	only one Bezier curve for the entire 3d rotation, meaning it can vary the speed
	along the path between keyframes but cannot deviate from that path.
	Part 1 is speeding/slowing to match angular speed when approaching/leaving a keyframe.
	Part 2 is detecting the "sharpness" of the corners and slowing down when approaching/leaving
	a sharp corner.
	
	:param A: tuple(frame, euler xyz) or None
	:param B: tuple(frame, euler xyz)
	:param C: tuple(frame, euler xyz) or None
	:return: ideal bezier slopes, 2 floats, tuple(approach,depart)
	"""
    if A is None and C is None:  # both sides are cutpoints
        return 1, 1
    if A is None:  # AB is an endpoint!
        # mark B-approach as a cutpoint (1) and B-depart as a cutpoint border (-1)
        return 1, -1
    if C is None:  # BC is an endpoint!
        # mark B-approach as a cutpoint border (-1) and B-depart as a cutpoint (1)
        return -1, 1
    # now i can proceed knowing that A and C are guaranteed to not be None

    quatA = core.euler_to_quaternion(A[1])
    quatB = core.euler_to_quaternion(B[1])
    quatC = core.euler_to_quaternion(C[1])

    # first, calc angle between each quat to get slerp "length"
    # technically the clamp shouldn't be necessary but floating point inaccuracy caused it to die
    asdf = abs(core.my_dot(quatA, quatB))
    asdf = core.clamp(asdf, -1.0, 1.0)
    angdist_AB = math.acos(asdf)
    asdf = abs(core.my_dot(quatB, quatC))
    asdf = core.clamp(asdf, -1.0, 1.0)
    angdist_BC = math.acos(asdf)
    # do some rounding to make extremely small numbers become zero
    if angdist_AB < CLOSE_TO_ZERO: angdist_AB = 0
    if angdist_BC < CLOSE_TO_ZERO: angdist_BC = 0
    # print(math.degrees(angdist_AB), math.degrees(angdist_BC))
    # use framedelta to turn the "length" into "speed"
    # this is also the "truespace slope" of the approach/depart
    # cannot be negative, can be zero
    angslope_AB = angdist_AB / (B[0] - A[0])
    angslope_BC = angdist_BC / (C[0] - B[0])
    # second, average/compromise them to get the "desired truespace slope"
    if HOW_TO_FIND_DESIRED_SLOPE_FOR_ROTATION == 1:
        # desired = angle bisector method
        angslope_AB, angslope_BC = calculate_slope_bisectors(
            angslope_AB, angslope_BC, AVERAGE_SLOPES_BY_HOW_MUCH)
    else:  # elif HOW_TO_FIND_DESIRED_SLOPE_FOR_POSITION == 2:
        # desired = total angular distance over total time
        total_slope = (angdist_AB + angdist_BC) / (C[0] - A[0])
        blend = AVERAGE_SLOPES_BY_HOW_MUCH
        angslope_AB = (blend * total_slope) + ((blend - 1) * angslope_AB)
        angslope_BC = (blend * total_slope) + ((blend - 1) * angslope_BC)

    # third, determine how sharp the corner is [0-1]. 3d rotations are wierd.
    # reduce the slopes by this factor.
    factor = get_corner_sharpness_factor(quatA, quatB, quatC)
    angslope_AB *= factor
    angslope_BC *= factor
    if angdist_AB != 0 and angdist_BC != 0 and B[0] - A[0] != 0 and C[0] - B[
            0] != 0:
        # print(factor)
        ANGLE_SHARPNESS_FACTORS.append(factor)

    # fourth, scale the desired truespace slope to the bezier scale
    # also handle any corner cases
    out1, out2 = desired_truespace_slope_to_bezier_slope(
        (B[0] - A[0], angdist_AB), angslope_AB, (C[0] - B[0], angdist_BC),
        angslope_BC)
    # return exactly 1 approach slope and one depart slope
    return out1, out2
def main(moreinfo=True):
	# the goal: extract rotation around the "arm" bone local X? axis and transfer it to rotation around the "armtwist" bone local axis
	
	# prompt PMX name
	core.MY_PRINT_FUNC("Please enter name of PMX input file:")
	input_filename_pmx = core.MY_FILEPROMPT_FUNC(".pmx")
	pmx = pmxlib.read_pmx(input_filename_pmx, moreinfo=moreinfo)
	core.MY_PRINT_FUNC("")
	# get bones
	realbones = pmx.bones
	
	twistbone_axes = []
	# then, grab the "twist" bones & save their fixed-rotate axes, if they have them
	# fallback plan: find the arm-to-elbow and elbow-to-wrist unit vectors and use those
	for i in range(len(jp_twistbones)):
		r = core.my_list_search(realbones, lambda x: x.name_jp == jp_twistbones[i], getitem=True)
		if r is None:
			core.MY_PRINT_FUNC("ERROR1: twist bone '{}'({}) cannot be found model, unable to continue. Ensure they use the correct semistandard names, or edit the script to change the JP names it is looking for.".format(jp_twistbones[i], eng_twistbones[i]))
			raise RuntimeError()
		if r.has_fixedaxis:
			# this bone DOES have fixed-axis enabled! use the unit vector in r[18]
			twistbone_axes.append(r.fixedaxis)
		else:
			# i can infer local axis by angle from arm-to-elbow or elbow-to-wrist
			start = core.my_list_search(realbones, lambda x: x.name_jp == jp_sourcebones[i], getitem=True)
			if start is None:
				core.MY_PRINT_FUNC("ERROR2: semistandard bone '%s' is missing from the model, unable to infer axis of rotation" % jp_sourcebones[i])
				raise RuntimeError()
			end = core.my_list_search(realbones, lambda x: x.name_jp == jp_pointat_bones[i], getitem=True)
			if end is None:
				core.MY_PRINT_FUNC("ERROR3: semistandard bone '%s' is missing from the model, unable to infer axis of rotation" % jp_pointat_bones[i])
				raise RuntimeError()
			start_pos = start.pos
			end_pos = end.pos
			# now have both startpoint and endpoint! find the delta!
			delta = [b - a for a,b in zip(start_pos, end_pos)]
			# normalize to length of 1
			length = core.my_euclidian_distance(delta)
			unit = [t / length for t in delta]
			twistbone_axes.append(unit)
	
	# done extracting axes limits from bone CSV, in list "twistbone_axes"
	core.MY_PRINT_FUNC("...done extracting axis limits from PMX...")
	
	
	###################################################################################
	# prompt VMD file name
	core.MY_PRINT_FUNC("Please enter name of VMD dance input file:")
	input_filename_vmd = core.MY_FILEPROMPT_FUNC(".vmd")
	
	# next, read/use/prune the dance vmd
	nicelist_in = vmdlib.read_vmd(input_filename_vmd, moreinfo=moreinfo)
	
	# sort boneframes into individual lists: one for each [Larm + Lelbow + Rarm + Relbow] and remove them from the master boneframelist
	# frames for all other bones stay in the master boneframelist
	all_sourcebone_frames = []
	for sourcebone in jp_sourcebones:
		# partition & writeback
		temp, nicelist_in.boneframes = core.my_list_partition(nicelist_in.boneframes, lambda x: x.name == sourcebone)
		# all frames for "sourcebone" get their own sublist here
		all_sourcebone_frames.append(temp)
	
	# verify that there is actually arm/elbow frames to process
	sourcenumframes = sum([len(x) for x in all_sourcebone_frames])
	if sourcenumframes == 0:
		core.MY_PRINT_FUNC("No arm/elbow bone frames are found in the VMD, nothing for me to do!")
		core.MY_PRINT_FUNC("Aborting: no files were changed")
		return None
	else:
		core.MY_PRINT_FUNC("...source contains " + str(sourcenumframes) + " arm/elbow bone frames to decompose...")
	
	if USE_OVERKEY_BANDAID:
		# to fix the path that the arms take during interpolation we need to overkey the frames
		# i.e. create intermediate frames that they should have been passing through already, to FORCE it to take the right path
		# i'm replacing the interpolation curves with actual frames
		for sublist in all_sourcebone_frames:
			newframelist = []
			sublist.sort(key=lambda x: x.f) # ensure they are sorted by frame number
			# for each frame
			for i in range(1, len(sublist)):
				this = sublist[i]
				prev = sublist[i-1]
				# use interpolation curve i to interpolate from i-1 to i
				# first: do i need to do anything or are they already close on the timeline?
				thisframenum = this.f
				prevframenum = prev.f
				if (thisframenum - prevframenum) <= OVERKEY_FRAME_SPACING:
					continue
				# if they are far enough apart that i need to do something,
				thisframequat = core.euler_to_quaternion(this.rot)
				prevframequat = core.euler_to_quaternion(prev.rot)
				# 3, 7, 11, 15 = r_ax, r_ay, r_bx, r_by
				bez = core.MyBezier((this.interp[3], this.interp[7]), (this.interp[11], this.interp[15]), resolution=50)
				# create new frames at these frame numbers, spacing is OVERKEY_FRAME_SPACING
				for interp_framenum in range(prevframenum + OVERKEY_FRAME_SPACING, thisframenum, OVERKEY_FRAME_SPACING):
					# calculate the x time percentage from prev frame to this frame
					x = (interp_framenum - prevframenum) / (thisframenum - prevframenum)
					# apply the interpolation curve to translate X to Y
					y = bez.approximate(x)
					# interpolate from prev to this by amount Y
					interp_quat = core.my_slerp(prevframequat, thisframequat, y)
					# begin building the new frame
					newframe = vmdstruct.VmdBoneFrame(
						name=this.name,  # same name
						f=interp_framenum,  # overwrite frame num
						pos=list(this.pos),  # same pos (but make a copy)
						rot=list(core.quaternion_to_euler(interp_quat)),  # overwrite euler angles
						phys_off=this.phys_off,  # same phys_off
						interp=list(core.bone_interpolation_default_linear)  # overwrite interpolation
					)
					newframelist.append(newframe)
				# overwrite thisframe interp curve with default too
				this.interp = list(core.bone_interpolation_default_linear) # overwrite custom interpolation
			# concat the new frames onto the existing frames for this sublist
			sublist += newframelist
			
	# re-count the number of frames for printing purposes
	totalnumframes = sum([len(x) for x in all_sourcebone_frames])
	overkeyframes = totalnumframes - sourcenumframes
	if overkeyframes != 0:
		core.MY_PRINT_FUNC("...overkeying added " + str(overkeyframes) + " arm/elbow bone frames...")
	core.MY_PRINT_FUNC("...beginning decomposition of " + str(totalnumframes) + " arm/elbow bone frames...")
	
	# now i am completely done reading the VMD file and parsing its data! everything has been distilled down to:
	# all_sourcebone_frames = [Larm, Lelbow, Rarm, Relbow] plus nicelist_in[1]
	
	###################################################################################
	# begin the actual calculations
	
	# output array
	new_twistbone_frames = []
	# progress tracker
	curr_progress = 0
	
	# for each sourcebone & corresponding twistbone,
	for (twistbone, axis_orig, sourcebone_frames) in zip(jp_twistbones, twistbone_axes, all_sourcebone_frames):
		# for each frame of the sourcebone,
		for frame in sourcebone_frames:
			# XYZrot = 567 euler
			quat_in = core.euler_to_quaternion(frame.rot)
			axis = list(axis_orig)	# make a copy to be safe
			
			# "swing twist decomposition"
			# swing = "local" x rotation and nothing else
			# swing = sourcebone, twist = twistbone
			(swing, twist) = swing_twist_decompose(quat_in, axis)
			
			# modify "frame" in-place
			# only modify the XYZrot to use new values
			new_sourcebone_euler = core.quaternion_to_euler(swing)
			frame.rot = list(new_sourcebone_euler)
			
			# create & store new twistbone frame
			# name=twistbone, framenum=copy, XYZpos=copy, XYZrot=new, phys=copy, interp16=copy
			new_twistbone_euler = core.quaternion_to_euler(twist)
			newframe = vmdstruct.VmdBoneFrame(
				name=twistbone,
				f=frame.f,
				pos=list(frame.pos),
				rot=list(new_twistbone_euler),
				phys_off=frame.phys_off,
				interp=list(frame.interp)
			)
			new_twistbone_frames.append(newframe)
			# print progress updates
			curr_progress += 1
			core.print_progress_oneline(curr_progress / totalnumframes)
	
	
	######################################################################
	# done with calculations!
	core.MY_PRINT_FUNC("...done with decomposition, now reassembling output...")
	# attach the list of newly created boneframes, modify the original input
	for sublist in all_sourcebone_frames:
		nicelist_in.boneframes += sublist
	nicelist_in.boneframes += new_twistbone_frames
	
	core.MY_PRINT_FUNC("")
	# write out the VMD
	output_filename_vmd = "%s_twistbones_for_%s.vmd" % \
						   (input_filename_vmd[0:-4], core.get_clean_basename(input_filename_pmx))
	output_filename_vmd = core.get_unused_file_name(output_filename_vmd)
	vmdlib.write_vmd(output_filename_vmd, nicelist_in, moreinfo=moreinfo)
	
	core.MY_PRINT_FUNC("Done!")
	return None
Beispiel #5
0
def main(moreinfo=True):
    # prompt PMX name
    core.MY_PRINT_FUNC("Please enter name of PMX input file:")
    input_filename_pmx = core.MY_FILEPROMPT_FUNC(".pmx")
    pmx = pmxlib.read_pmx(input_filename_pmx, moreinfo=moreinfo)
    # get bones
    realbones = pmx.bones
    # then, make 2 lists: one starting from jp_righttoe, one starting from jp_lefttoe
    # start from each "toe" bone (names are known), go parent-find-parent-find until reaching no-parent
    bonechain_r = build_bonechain(realbones, jp_righttoe)
    bonechain_l = build_bonechain(realbones, jp_lefttoe)

    # assert that the bones were found, have correct names, and are in the correct positions
    # also verifies that they are direct parent-child with nothing in between
    try:
        assert bonechain_r[-1].name == jp_righttoe
        assert bonechain_r[-2].name == jp_rightfoot
        assert bonechain_l[-1].name == jp_lefttoe
        assert bonechain_l[-2].name == jp_leftfoot
    except AssertionError:
        core.MY_PRINT_FUNC(
            "ERROR: unexpected structure found for foot/toe bones, verify semistandard names and structure"
        )
        raise RuntimeError()

    # then walk down these 2 lists, add each name to a set: build union of all relevant bones
    relevant_bones = set()
    for b in bonechain_r + bonechain_l:
        relevant_bones.add(b.name)

    # check if waist-cancellation bones are in "relevant_bones", print a warning if they are
    if jp_left_waistcancel in relevant_bones or jp_right_waistcancel in relevant_bones:
        # TODO LOW: i probably could figure out how to support them but this whole script is useless so idgaf
        core.MY_PRINT_FUNC(
            "Warning: waist-cancellation bones found in the model! These are not supported, tool may produce bad results! Attempting to continue..."
        )

    # also need to find initial positions of ik bones (names are known)
    # build a full parentage-chain for each leg
    bonechain_ikr = build_bonechain(realbones, jp_righttoe_ik)
    bonechain_ikl = build_bonechain(realbones, jp_lefttoe_ik)

    # verify that the ik bones were found, have correct names, and are in the correct positions
    try:
        assert bonechain_ikr[-1].name == jp_righttoe_ik
        assert bonechain_ikr[-2].name == jp_rightfoot_ik
        assert bonechain_ikl[-1].name == jp_lefttoe_ik
        assert bonechain_ikl[-2].name == jp_leftfoot_ik
    except AssertionError:
        core.MY_PRINT_FUNC(
            "ERROR: unexpected structure found for foot/toe IK bones, verify semistandard names and structure"
        )
        raise RuntimeError()

    # verify that the bonechains are symmetric in length
    try:
        assert len(bonechain_l) == len(bonechain_r)
        assert len(bonechain_ikl) == len(bonechain_ikr)
    except AssertionError:
        core.MY_PRINT_FUNC(
            "ERROR: unexpected structure found, model is not left-right symmetric"
        )
        raise RuntimeError()

    # determine how many levels of parentage, this value "t" should hold the first level where they are no longer shared
    t = 0
    while bonechain_l[t].name == bonechain_ikl[t].name:
        t += 1
    # back off one level
    lowest_shared_parent = t - 1

    # now i am completely done with the bones CSV, all the relevant info has been distilled down to:
    # !!! bonechain_r, bonechain_l, bonechain_ikr, bonechain_ikl, relevant_bones
    core.MY_PRINT_FUNC("...identified " + str(len(bonechain_l)) +
                       " bones per leg-chain, " + str(len(relevant_bones)) +
                       " relevant bones total")
    core.MY_PRINT_FUNC("...identified " + str(len(bonechain_ikl)) +
                       " bones per IK leg-chain")

    ###################################################################################
    # prompt VMD file name
    core.MY_PRINT_FUNC("Please enter name of VMD dance input file:")
    input_filename_vmd = core.MY_FILEPROMPT_FUNC(".vmd")
    nicelist_in = vmdlib.read_vmd(input_filename_vmd, moreinfo=moreinfo)

    # check if this VMD uses IK or not, print a warning if it does
    any_ik_on = False
    for ikdispframe in nicelist_in.ikdispframes:
        for ik_bone in ikdispframe.ikbones:
            if ik_bone.enable is True:
                any_ik_on = True
                break
    if any_ik_on:
        core.MY_PRINT_FUNC(
            "Warning: the input VMD already has IK enabled, there is no point in running this script. Attempting to continue..."
        )

    # reduce down to only the boneframes for the relevant bones
    # also build a list of each framenumber with a frame for a bone we care about
    relevant_framenums = set()
    boneframe_list = []
    for boneframe in nicelist_in.boneframes:
        if boneframe.name in relevant_bones:
            boneframe_list.append(boneframe)
            relevant_framenums.add(boneframe.f)
    # sort the boneframes by frame number
    boneframe_list.sort(key=lambda x: x.f)
    # make the relevant framenumbers also an ascending list
    relevant_framenums = sorted(list(relevant_framenums))

    boneframe_dict = dict()
    # now restructure the data from a list to a dictionary, keyed by bone name. also discard excess data when i do
    for b in boneframe_list:
        if b.name not in boneframe_dict:
            boneframe_dict[b.name] = []
        # only storing the frame#(1) + position(234) + rotation values(567)
        saveme = [b.f, *b.pos, *b.rot]
        boneframe_dict[b.name].append(saveme)

    core.MY_PRINT_FUNC(
        "...running interpolation to rectangularize the frames...")

    has_warned = False
    # now fill in the blanks by using interpolation, if needed
    for key, bone in boneframe_dict.items():  # for each bone,
        # start a list of frames generated by interpolation
        interpframe_list = []
        i = 0
        j = 0
        while j < len(relevant_framenums):  # for each frame it should have,
            if i == len(bone):
                # if i is beyond end of bone, then copy the values from the last frame and use as a new frame
                newframe = [relevant_framenums[j]] + bone[-1][1:7]
                interpframe_list.append(newframe)
                j += 1
            elif bone[i][0] == relevant_framenums[j]:  # does it have it?
                i += 1
                j += 1
            else:
                # TODO LOW: i could modify this to include my interpolation curve math now that I understand it, but i dont care
                if not has_warned:
                    core.MY_PRINT_FUNC(
                        "Warning: interpolation is needed but interpolation curves are not fully tested! Assuming linear interpolation..."
                    )
                    has_warned = True
                # if there is a mismatch then the target framenum is less than the boneframe framenum
                # build a frame that has frame# + position(123) + rotation values(456)
                newframe = [relevant_framenums[j]]
                # if target is less than the current boneframe, interp between here and prev boneframe
                for p in range(1, 4):
                    # interpolate for each position offset
                    newframe.append(
                        core.linear_map(bone[i][0], bone[i][p], bone[i - 1][0],
                                        bone[i - 1][p], relevant_framenums[j]))
                # rotation interpolation must happen in the quaternion-space
                quat1 = core.euler_to_quaternion(bone[i - 1][4:7])
                quat2 = core.euler_to_quaternion(bone[i][4:7])
                # desired frame is relevant_framenums[j] = d
                # available frames are bone[i-1][0] = s and bone[i][0] = e
                # percentage = (d - s) / (e - s)
                percentage = (relevant_framenums[j] -
                              bone[i - 1][0]) / (bone[i][0] - bone[i - 1][0])
                quat_slerp = core.my_slerp(quat1, quat2, percentage)
                euler_slerp = core.quaternion_to_euler(quat_slerp)
                newframe += euler_slerp
                interpframe_list.append(newframe)
                j += 1
        bone += interpframe_list
        bone.sort(key=core.get1st)

    # the dictionary should be fully filled out and rectangular now
    for bone in boneframe_dict:
        assert len(boneframe_dict[bone]) == len(relevant_framenums)

    # now i am completely done reading the VMD file and parsing its data! everything has been distilled down to:
    # relevant_framenums, boneframe_dict

    ###################################################################################
    # begin the actual calculations
    core.MY_PRINT_FUNC("...beginning forward kinematics computation for " +
                       str(len(relevant_framenums)) + " frames...")

    # output array
    ikframe_list = []

    # have list of bones, parentage, initial pos
    # have list of frames
    # now i "run the dance" and build the ik frames
    # for each relevant frame,
    for I in range(len(relevant_framenums)):
        # for each side,
        for (thisik, this_chain) in zip([bonechain_ikr, bonechain_ikl],
                                        [bonechain_r, bonechain_l]):
            # for each bone in this_chain (ordered, start with root!),
            for J in range(len(this_chain)):
                # reset the current to be the inital position again
                this_chain[J].reset()
            # for each bone in this_chain (ordered, start with toe! do children before parents!)
            # also, don't read/use root! because the IK are also children of root, they inherit the same root transformations
            # count backwards from end to lowest_shared_parent, not including lowest_shared_parent
            for J in range(len(this_chain) - 1, lowest_shared_parent, -1):
                # get bone J within this_chain, translate to name
                name = this_chain[J].name
                # get bone [name] at index I: position & rotation
                try:
                    xpos, ypos, zpos, xrot, yrot, zrot = boneframe_dict[name][
                        I][1:7]
                except KeyError:
                    continue
                # apply position offset to self & children
                # also resets the currposition when changing frames
                for K in range(J, len(this_chain)):
                    # set this_chain[K].current456 = current456 + position
                    this_chain[K].xcurr += xpos
                    this_chain[K].ycurr += ypos
                    this_chain[K].zcurr += zpos
                # apply rotation offset to all children, but not self
                _origin = [
                    this_chain[J].xcurr, this_chain[J].ycurr,
                    this_chain[J].zcurr
                ]
                _angle = [xrot, yrot, zrot]
                _angle_quat = core.euler_to_quaternion(_angle)
                for K in range(J, len(this_chain)):
                    # set this_chain[K].current456 = current rotated around this_chain[J].current456
                    _point = [
                        this_chain[K].xcurr, this_chain[K].ycurr,
                        this_chain[K].zcurr
                    ]
                    _newpoint = rotate3d(_origin, _angle_quat, _point)
                    (this_chain[K].xcurr, this_chain[K].ycurr,
                     this_chain[K].zcurr) = _newpoint

                    # also rotate the angle of this bone
                    curr_angle_euler = [
                        this_chain[K].xrot, this_chain[K].yrot,
                        this_chain[K].zrot
                    ]
                    curr_angle_quat = core.euler_to_quaternion(
                        curr_angle_euler)
                    new_angle_quat = core.hamilton_product(
                        _angle_quat, curr_angle_quat)
                    new_angle_euler = core.quaternion_to_euler(new_angle_quat)
                    (this_chain[K].xrot, this_chain[K].yrot,
                     this_chain[K].zrot) = new_angle_euler
                    pass
                pass
            # now i have cascaded this frame's pose data down the this_chain
            # grab foot/toe (-2 and -1) current position and calculate IK offset from that

            # first, foot:
            # footikend - footikinit = footikoffset
            xfoot = this_chain[-2].xcurr - thisik[-2].xinit
            yfoot = this_chain[-2].ycurr - thisik[-2].yinit
            zfoot = this_chain[-2].zcurr - thisik[-2].zinit
            # save as boneframe to be ultimately formatted for VMD:
            # 	need bonename = (known)
            # 	need frame# = relevantframe#s[I]
            # 	position = calculated
            # 	rotation = 0
            # 	phys = not disabled
            # 	interp = default (20/107)
            # # then, foot-angle: just copy the angle that the foot has
            if STORE_IK_AS_FOOT_ONLY:
                ikframe = [
                    thisik[-2].name, relevant_framenums[I], xfoot, yfoot,
                    zfoot, this_chain[-2].xrot, this_chain[-2].yrot,
                    this_chain[-2].zrot, False
                ]
            else:
                ikframe = [
                    thisik[-2].name, relevant_framenums[I], xfoot, yfoot,
                    zfoot, 0.0, 0.0, 0.0, False
                ]
            ikframe += [20] * 8
            ikframe += [107] * 8
            # append the freshly-built frame
            ikframe_list.append(ikframe)
            if not STORE_IK_AS_FOOT_ONLY:
                # then, toe:
                # toeikend - toeikinit - footikoffset = toeikoffset
                xtoe = this_chain[-1].xcurr - thisik[-1].xinit - xfoot
                ytoe = this_chain[-1].ycurr - thisik[-1].yinit - yfoot
                ztoe = this_chain[-1].zcurr - thisik[-1].zinit - zfoot
                ikframe = [
                    thisik[-1].name, relevant_framenums[I], xtoe, ytoe, ztoe,
                    0.0, 0.0, 0.0, False
                ]
                ikframe += [20] * 8
                ikframe += [107] * 8
                # append the freshly-built frame
                ikframe_list.append(ikframe)
        # now done with a timeframe for all bones on both sides
        # print progress updates
        core.print_progress_oneline(I / len(relevant_framenums))

    core.MY_PRINT_FUNC(
        "...done with forward kinematics computation, now writing output...")

    if INCLUDE_IK_ENABLE_FRAME:
        # create a single ikdispframe that enables the ik bones at frame 0
        ikbones = [
            vmdstruct.VmdIkbone(name=jp_rightfoot_ik, enable=True),
            vmdstruct.VmdIkbone(name=jp_righttoe_ik, enable=True),
            vmdstruct.VmdIkbone(name=jp_leftfoot_ik, enable=True),
            vmdstruct.VmdIkbone(name=jp_lefttoe_ik, enable=True)
        ]
        ikdispframe_list = [
            vmdstruct.VmdIkdispFrame(f=0, disp=True, ikbones=ikbones)
        ]
    else:
        ikdispframe_list = []
        core.MY_PRINT_FUNC(
            "Warning: IK following will NOT be enabled when this VMD is loaded, you will need enable it manually!"
        )

    # convert old-style bonelist ikframe_list to new object format
    ikframe_list = [
        vmdstruct.VmdBoneFrame(name=r[0],
                               f=r[1],
                               pos=r[2:5],
                               rot=r[5:8],
                               phys_off=r[8],
                               interp=r[9:]) for r in ikframe_list
    ]
    # build actual VMD object
    nicelist_out = vmdstruct.Vmd(
        vmdstruct.VmdHeader(2, "SEMISTANDARD-IK-BONES--------"),
        ikframe_list,  # bone
        [],  # morph
        [],  # cam
        [],  # light
        [],  # shadow
        ikdispframe_list  # ikdisp
    )

    # write out
    output_filename_vmd = "%s_ik_from_%s.vmd" % \
           (input_filename_vmd[0:-4], core.get_clean_basename(input_filename_pmx))
    output_filename_vmd = core.get_unused_file_name(output_filename_vmd)
    vmdlib.write_vmd(output_filename_vmd, nicelist_out, moreinfo=moreinfo)

    core.MY_PRINT_FUNC("Done!")
    return None