Files
diffvg/gradientmesh/gmtypes.py
2023-05-17 16:27:52 +02:00

301 lines
8.5 KiB
Python

#!/usr/bin/env ipython
from __future__ import annotations
import torch
from random import uniform
import math
from util import rgb2hex, any_map
class Point:
"""2D point, optionally with control points;
alternatively, 2-vector"""
def __init__(self, x: float, y: float,
round=False):
self.x = x
self.y = y
if round:
self.round()
def as_xy(self):
return [self.x, self.y]
def round(self):
self.x = int(self.x * 100) / 100.0
self.y = int(self.y * 100) / 100.0
return self
def add(self, pt: Point):
self.x += pt.x
self.y += pt.y
return self
def mult(self, pt: Point):
self.x *= pt.x
self.y *= pt.y
return self
@classmethod
def random(cls, rx=(0, 1), ry=(0, 1)):
# Clamp to (0, 1)
rx = (max(0, rx[0]), min(1, max(0, rx[1])))
ry = (max(0, ry[0]), min(1, max(0, ry[1])))
out = cls(uniform(*rx), uniform(*ry))
out.round()
return out
def __hash__(self):
# Used for removing duplicate points
return id(self)
def __repr__(self):
return f"P<({self.x}, {self.y})>"
def __str__(self):
return self.__repr__()
class Patch:
"""Bicubic patch."""
def __init__(self,
points: list[Point],
controls: list[list[Point]],
color=(0.2, 0.5, 0.7, 1.0)):
self.points = points
self.controls = controls
self.color = color
def translate(self, pt: Point):
for p in self.points:
p.add(pt)
for q in self.controls:
for p in q:
p.add(pt)
def scale(self, pt: Point):
for p in self.points:
p.mult(pt)
for q in self.controls:
for p in q:
p.mult(pt)
@classmethod
def random(cls, degree=4, num_control_points=2):
num_control_points = [num_control_points] * degree
"""Returns a random Patch with `degree` vertices
and `num_control_points` control points per edge."""
# Random tweaks to regular polygon base
angle = 2 * math.pi / degree
angle = uniform(0.8 * angle, 1.2 * angle)
points = []
for i in range(degree):
pt = Point(
uniform(0.3, 0.7) + 0.5 * math.cos(i * angle),
uniform(0.3, 0.7) + 0.5 * math.sin(i * angle)
)
# Stochastically clamp to (0,1)
for c in ['x', 'y']:
if (v := getattr(pt, c)) > 1:
diff = v - 1
setattr(pt, c, v - uniform(diff, 2 * diff))
elif v < 0:
diff = -v
setattr(pt, c, v + uniform(diff, 2 * diff))
points.append(pt)
control_points = []
for i in range(len(num_control_points)):
pt = points[i]
npt = points[i+1 if i+1 < degree else 0]
ncp = num_control_points[i]
dx = (npt.x - pt.x) / (ncp + 1)
dy = (npt.y - pt.y) / (ncp + 1)
control_points.append([
Point(
pt.x + j * dx * uniform(0.8, 1.2) + uniform(0, 0.2),
pt.y + j * dy * uniform(0.8, 1.2) + uniform(0, 0.2)
) for j in range(1, ncp+1)
])
out = cls(points, control_points)
out.color = (
uniform(0, 1),
uniform(0, 1),
uniform(0, 1),
0.7
)
return out
def __repr__(self):
out = f"F<({rgb2hex(*self.color)})"
out += f"[{', '.join([str(x) for x in self.points])}]>"
return out
class Quad(Patch):
"""Quadrilateral bicubic patch."""
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
# Assign 4 vertices as self.{top, bototm, left, right}
self.top, self.right, self.bottom, self.left = self.points
by_y = sorted(self.points, key=lambda pt: pt.y)
self.top, self.bottom = by_y[0], by_y[-1]
by_x = sorted([pt for pt in self.points
if pt not in [self.top, self.bottom]],
key=lambda pt: pt.x)
self.left, self.right = by_x
# Assign 4 edges as self.{northeat, southeast, southwest, northwest}
self.northeast = self.controls[self.points.index(self.top)]
self.southeast = self.controls[self.points.index(self.right)]
self.southwest = self.controls[self.points.index(self.bottom)]
self.northwest = self.controls[self.points.index(self.left)]
self.set_points()
def set_points(self):
"""Reset self.points and self.controls; used after mutating
e.g. self.top, self.southwest &c."""
self.points = [self.left, self.top,
self.right, self.bottom]
self.controls = [self.northwest, self.northeast,
self.southeast, self.southwest]
class PointMapping:
"""Mapping of unique points in a mesh to separate shapes for diffvg."""
def __init__(self, points, controls, raw_points, colors):
self.points = points
self.controls = controls
self.raw_points = raw_points
self.data = torch.tensor(
[pt.as_xy() for pt in raw_points], requires_grad=True
)
self.colors = colors
def as_shapes(self):
out = []
for i in range(len(self.points)):
quad = self.points[i]
quadpoints = []
for j in range(len(quad)):
quadpoints.append(quad[j])
quadpoints += self.controls[i][j]
out.append(quadpoints)
return [torch.stack(x) for x in
any_map(lambda idx: self.data[idx], out)]
class GradientMesh:
"""Bicubic quadrilateral mesh."""
def __init__(self, *quads: Quad):
self.quads = quads
def as_mapping(self):
"""Convert GradientMesh to PointMapping"""
points = []
controls = []
raw_points = []
for q in self.quads:
points.append(q.points)
controls.append(q.controls)
raw_points += q.points
for cp in q.controls:
raw_points += cp
raw_points = list(set(raw_points))
points = any_map(lambda p: raw_points.index(p), points)
controls = any_map(lambda p: raw_points.index(p), controls)
colors = torch.tensor([q.color for q in self.quads],
requires_grad=True)
return PointMapping(points, controls, raw_points, colors)
def from_mapping(self, mapping: PointMapping):
pass
def average_points(*points: list[Point]) -> Point:
"""Average (i.e. geometric center) of points."""
x = sum([pt.x for pt in points]) / len(points)
y = sum([pt.y for pt in points]) / len(points)
return Point(x, y)
def join_quads(a: Quad, b: Quad, c: Quad, d: Quad,
scale=True, translate=True,
step=10):
"""Join 4 quadrilaterals so that they form a mesh with a center point."""
def combine_cp(cpa, cpb):
return [average_points(a, b) for a, b in zip(cpa, cpb)]
# If each quad occupies full space, make it so that they occupy 1/4 of space
if scale:
a.scale(Point(0.5, 0.5))
b.scale(Point(0.5, 0.5))
c.scale(Point(0.5, 0.5))
d.scale(Point(0.5, 0.5))
# If quads are on top of each other, translate so they are not
if translate:
b.translate(a.top)
c.translate(a.right)
d.translate(a.bottom)
# Equalize centerpoint
a.right, b.bottom, c.left, d.top = [
average_points(a.right, b.bottom, c.left, d.top)
] * 4
# Equalize non-center shared points
a.top, b.left = [average_points(a.top, b.left)] * 2
a.bottom, d.left = [average_points(a.bottom, d.left)] * 2
b.right, c.top = [average_points(b.right, c.top)] * 2
c.bottom, d.right = [average_points(c.bottom, d.right)] * 2
# Equalize edges
a.northeast, b.southwest = (
(comb := combine_cp(a.northeast, b.southwest)),
comb[::-1]
)
b.southeast, c.northwest = (
(comb := combine_cp(b.southeast, c.northwest)),
comb[::-1]
)
c.southwest, d.northeast = (
(comb := combine_cp(c.southwest, d.northeast)),
comb[::-1]
)
d.northwest, a.southeast = (
(comb := combine_cp(d.northwest, a.southeast)),
comb[::-1]
)
# Update points
for q in [a, b, c, d]:
q.set_points()