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bemaniutils/bemani/format/afp/blend/blend.py
2021-05-29 22:11:15 +00:00

398 lines
15 KiB
Python

import multiprocessing
import signal
from PIL import Image # type: ignore
from typing import Any, List, Optional, Sequence
from ..types import Color, Matrix, Point
def clamp(color: float) -> int:
return min(max(0, round(color)), 255)
def blend_normal(
# RGBA color tuple representing what's already at the dest.
dest: Sequence[int],
# RGBA color tuple representing the source we want to blend to the dest.
src: Sequence[int],
) -> Sequence[int]:
# "Normal" blend mode, which is just alpha blending. Various games use the DX
# equation Src * As + Dst * (1 - As). We premultiply Dst by Ad as well, since
# we are blitting onto a destination that could have transparency. Once we are
# done, we divide out the premultiplied Ad in order to put the pixes back to
# their full blended values since we are not setting the destination alpha to 1.0.
# This enables partial transparent backgrounds to work properly.
# Short circuit for speed.
if src[3] == 0:
return dest
if src[3] == 255:
return src
# Calculate alpha blending.
srcpercent = src[3] / 255.0
destpercent = dest[3] / 255.0
srcremainder = 1.0 - srcpercent
new_alpha = max(min(0.0, srcpercent + destpercent * srcremainder), 1.0)
return (
clamp(((dest[0] * destpercent * srcremainder) + (src[0] * srcpercent)) / new_alpha),
clamp(((dest[1] * destpercent * srcremainder) + (src[1] * srcpercent)) / new_alpha),
clamp(((dest[2] * destpercent * srcremainder) + (src[2] * srcpercent)) / new_alpha),
clamp(255 * new_alpha)
)
def blend_addition(
# RGBA color tuple representing what's already at the dest.
dest: Sequence[int],
# RGBA color tuple representing the source we want to blend to the dest.
src: Sequence[int],
) -> Sequence[int]:
# "Addition" blend mode, which is used for fog/clouds/etc. Various games use the DX
# equation Src * As + Dst * 1. It appears jubeat does not premultiply the source
# by its alpha component.
# Short circuit for speed.
if src[3] == 0:
return dest
# Calculate final color blending.
srcpercent = src[3] / 255.0
return (
clamp(dest[0] + (src[0] * srcpercent)),
clamp(dest[1] + (src[1] * srcpercent)),
clamp(dest[2] + (src[2] * srcpercent)),
# Additive blending doesn't actually make sense on semi-transparent destinations,
# as that implies that the semi-transparent pixel will be later displayed on top
# of something else. That doesn't work since additive blending needs to non-linearly
# mix with the destination. So, in reality, we should be doing what subtractive
# blending does and keeping the destination alpha (which should always be 255),
# but if somebody renders an animation with additive blending meant to go over a
# background onto a transparent or semi-transparent background this will make the
# resulting graphic look more correct.
clamp(dest[3] + (255 * srcpercent)),
)
def blend_subtraction(
# RGBA color tuple representing what's already at the dest.
dest: Sequence[int],
# RGBA color tuple representing the source we want to blend to the dest.
src: Sequence[int],
) -> Sequence[int]:
# "Subtraction" blend mode, used for darkening an image. Various games use the DX
# equation Dst * 1 - Src * As. It appears jubeat does not premultiply the source
# by its alpha component much like the "additive" blend above..
# Short circuit for speed.
if src[3] == 0:
return dest
# Calculate final color blending.
srcpercent = src[3] / 255.0
return (
clamp(dest[0] - (src[0] * srcpercent)),
clamp(dest[1] - (src[1] * srcpercent)),
clamp(dest[2] - (src[2] * srcpercent)),
dest[3],
)
def blend_multiply(
# RGBA color tuple representing what's already at the dest.
dest: Sequence[int],
# RGBA color tuple representing the source we want to blend to the dest.
src: Sequence[int],
) -> Sequence[int]:
# "Multiply" blend mode, used for darkening an image. Various games use the DX
# equation Src * 0 + Dst * Src. It appears jubeat uses the alternative formula
# Src * Dst + Dst * (1 - As) which reduces to the first equation as long as the
# source alpha is always 255.
# Calculate final color blending.
return (
clamp(255 * ((dest[0] / 255.0) * (src[0] / 255.0))),
clamp(255 * ((dest[1] / 255.0) * (src[1] / 255.0))),
clamp(255 * ((dest[2] / 255.0) * (src[2] / 255.0))),
dest[3],
)
def affine_composite(
img: Image.Image,
add_color: Color,
mult_color: Color,
transform: Matrix,
mask: Optional[Image.Image],
blendfunc: int,
texture: Image.Image,
single_threaded: bool = False,
) -> Image.Image:
# Calculate the inverse so we can map canvas space back to texture space.
try:
inverse = transform.inverse()
except ZeroDivisionError:
# If this happens, that means one of the scaling factors was zero, making
# this object invisible. We can ignore this since the object should not
# be drawn.
return img
# Warn if we have an unsupported blend.
if blendfunc not in {0, 1, 2, 3, 8, 9, 70, 256, 257}:
print(f"WARNING: Unsupported blend {blendfunc}")
return img
# These are calculated properties and caching them outside of the loop
# speeds things up a bit.
imgwidth = img.width
imgheight = img.height
texwidth = texture.width
texheight = texture.height
# Calculate the maximum range of update this texture can possibly reside in.
pix1 = transform.multiply_point(Point.identity())
pix2 = transform.multiply_point(Point.identity().add(Point(texwidth, 0)))
pix3 = transform.multiply_point(Point.identity().add(Point(0, texheight)))
pix4 = transform.multiply_point(Point.identity().add(Point(texwidth, texheight)))
# Map this to the rectangle we need to sweep in the rendering image.
minx = max(int(min(pix1.x, pix2.x, pix3.x, pix4.x)), 0)
maxx = min(int(max(pix1.x, pix2.x, pix3.x, pix4.x)) + 1, imgwidth)
miny = max(int(min(pix1.y, pix2.y, pix3.y, pix4.y)), 0)
maxy = min(int(max(pix1.y, pix2.y, pix3.y, pix4.y)) + 1, imgheight)
if maxx <= minx or maxy <= miny:
# This image is entirely off the screen!
return img
cores = multiprocessing.cpu_count()
if single_threaded or cores < 2:
# Get the data in an easier to manipulate and faster to update fashion.
imgmap = list(img.getdata())
texmap = list(texture.getdata())
if mask:
alpha = mask.split()[-1]
maskmap = alpha.tobytes('raw', 'L')
else:
maskmap = None
# We don't have enough CPU cores to bother multiprocessing.
for imgy in range(miny, maxy):
for imgx in range(minx, maxx):
# Determine offset
imgoff = imgx + (imgy * imgwidth)
# Calculate what texture pixel data goes here.
texloc = inverse.multiply_point(Point(float(imgx + 0.5), float(imgy + 0.5)))
texx, texy = texloc.as_tuple()
# If we're out of bounds, don't update.
if texx < 0 or texy < 0 or texx >= texwidth or texy >= texheight:
continue
# Blend it.
texoff = texx + (texy * texwidth)
if maskmap is not None and maskmap[imgoff] == 0:
# This pixel is masked off!
continue
imgmap[imgoff] = blend_point(add_color, mult_color, texmap[texoff], imgmap[imgoff], blendfunc)
img.putdata(imgmap)
else:
imgbytes = img.tobytes('raw', 'RGBA')
texbytes = texture.tobytes('raw', 'RGBA')
if mask:
alpha = mask.split()[-1]
maskbytes = alpha.tobytes('raw', 'L')
else:
maskbytes = None
# Let's spread the load across multiple processors.
procs: List[multiprocessing.Process] = []
work: multiprocessing.Queue = multiprocessing.Queue()
results: multiprocessing.Queue = multiprocessing.Queue()
expected: int = 0
interrupted: bool = False
def ctrlc(sig: Any, frame: Any) -> None:
nonlocal interrupted
interrupted = True
previous_handler = signal.getsignal(signal.SIGINT)
signal.signal(signal.SIGINT, ctrlc)
for _ in range(cores):
proc = multiprocessing.Process(
target=pixel_renderer,
args=(
work,
results,
minx,
maxx,
imgwidth,
texwidth,
texheight,
inverse,
add_color,
mult_color,
blendfunc,
imgbytes,
texbytes,
maskbytes,
),
)
procs.append(proc)
proc.start()
for imgy in range(miny, maxy):
work.put(imgy)
expected += 1
lines: List[bytes] = [
imgbytes[x:(x + (imgwidth * 4))]
for x in range(
0,
imgwidth * imgheight * 4,
imgwidth * 4,
)
]
for _ in range(expected):
imgy, result = results.get()
lines[imgy] = result
for proc in procs:
work.put(None)
for proc in procs:
proc.join()
signal.signal(signal.SIGINT, previous_handler)
if interrupted:
raise KeyboardInterrupt()
img = Image.frombytes('RGBA', (imgwidth, imgheight), b''.join(lines))
return img
def blend_mask_create(
# RGBA color tuple representing what's already at the dest.
dest: Sequence[int],
# RGBA color tuple representing the source we want to blend to the dest.
src: Sequence[int],
) -> Sequence[int]:
# Mask creating just allows a pixel to be drawn if the source image has a nonzero
# alpha, according to the SWF spec.
if src[3] != 0:
return (255, 0, 0, 255)
else:
return (0, 0, 0, 0)
def blend_mask_combine(
# RGBA color tuple representing what's already at the dest.
dest: Sequence[int],
# RGBA color tuple representing the source we want to blend to the dest.
src: Sequence[int],
) -> Sequence[int]:
# Mask blending just takes the source and destination and ands them together, making
# a final mask that is the intersection of the original mask and the new mask. The
# reason we even have a color component to this is for debugging visibility.
if dest[3] != 0 and src[3] != 0:
return (255, 0, 0, 255)
else:
return (0, 0, 0, 0)
def pixel_renderer(
work: multiprocessing.Queue,
results: multiprocessing.Queue,
minx: int,
maxx: int,
imgwidth: int,
texwidth: int,
texheight: int,
inverse: Matrix,
add_color: Color,
mult_color: Color,
blendfunc: int,
imgbytes: bytes,
texbytes: bytes,
maskbytes: Optional[bytes],
) -> None:
while True:
imgy = work.get()
if imgy is None:
return
result: List[Sequence[int]] = []
for imgx in range(imgwidth):
# Determine offset
imgoff = imgx + (imgy * imgwidth)
if imgx < minx or imgx >= maxx:
result.append(imgbytes[(imgoff * 4):((imgoff + 1) * 4)])
continue
# Calculate what texture pixel data goes here.
texloc = inverse.multiply_point(Point(float(imgx + 0.5), float(imgy + 0.5)))
texx, texy = texloc.as_tuple()
# If we're out of bounds, don't update.
if texx < 0 or texy < 0 or texx >= texwidth or texy >= texheight:
result.append(imgbytes[(imgoff * 4):((imgoff + 1) * 4)])
continue
# Blend it.
texoff = texx + (texy * texwidth)
if maskbytes is not None and maskbytes[imgoff] == 0:
# This pixel is masked off!
result.append(imgbytes[(imgoff * 4):((imgoff + 1) * 4)])
continue
result.append(blend_point(add_color, mult_color, texbytes[(texoff * 4):((texoff + 1) * 4)], imgbytes[(imgoff * 4):((imgoff + 1) * 4)], blendfunc))
linebytes = bytes([channel for pixel in result for channel in pixel])
results.put((imgy, linebytes))
def blend_point(
add_color: Color,
mult_color: Color,
# This should be a sequence of exactly 4 values, either bytes or a tuple.
src_color: Sequence[int],
# This should be a sequence of exactly 4 values, either bytes or a tuple.
dest_color: Sequence[int],
blendfunc: int,
) -> Sequence[int]:
# Calculate multiplicative and additive colors against the source.
src_color = (
clamp((src_color[0] * mult_color.r) + (255 * add_color.r)),
clamp((src_color[1] * mult_color.g) + (255 * add_color.g)),
clamp((src_color[2] * mult_color.b) + (255 * add_color.b)),
clamp((src_color[3] * mult_color.a) + (255 * add_color.a)),
)
if blendfunc == 3:
return blend_multiply(dest_color, src_color)
# TODO: blend mode 4, which is "screen" blending according to SWF references. I've only seen this
# in Jubeat and it implements it using OpenGL equation Src * (1 - Dst) + Dst * 1.
# TODO: blend mode 5, which is "lighten" blending according to SWF references. Jubeat does not
# premultiply by alpha, but the GL/DX equation is max(Src * As, Dst * 1).
# TODO: blend mode 6, which is "darken" blending according to SWF references. Jubeat does not
# premultiply by alpha, but the GL/DX equation is min(Src * As, Dst * 1).
# TODO: blend mode 10, which is "invert" according to SWF references. The only game I could find
# that implemented this had equation Src * (1 - Dst) + Dst * (1 - As).
# TODO: blend mode 13, which is "overlay" according to SWF references. The equation seems to be
# Src * Dst + Dst * Src but Jubeat thinks it should be Src * Dst + Dst * (1 - As).
elif blendfunc == 8:
return blend_addition(dest_color, src_color)
elif blendfunc == 9 or blendfunc == 70:
return blend_subtraction(dest_color, src_color)
# TODO: blend mode 75, which is not in the SWF spec and appears to have the equation
# Src * (1 - Dst) + Dst * (1 - Src).
elif blendfunc == 256:
# Dummy blend function for calculating masks.
return blend_mask_combine(dest_color, src_color)
elif blendfunc == 257:
# Dummy blend function for calculating masks.
return blend_mask_create(dest_color, src_color)
else:
return blend_normal(dest_color, src_color)