kopia lustrzana https://github.com/villares/sketch-a-day
143 wiersze
4.9 KiB
Python
143 wiersze
4.9 KiB
Python
# -*- coding: utf-8 -*-
|
|
|
|
ROTATION = {0: 0,
|
|
BOTTOM: 0,
|
|
DOWN: 0,
|
|
1: HALF_PI,
|
|
LEFT: HALF_PI,
|
|
2: PI,
|
|
TOP: PI,
|
|
UP: PI,
|
|
3: PI + HALF_PI,
|
|
RIGHT: PI + HALF_PI,
|
|
BOTTOM + RIGHT: 0,
|
|
DOWN + RIGHT: 0,
|
|
DOWN + LEFT: HALF_PI,
|
|
BOTTOM + LEFT: HALF_PI,
|
|
TOP + LEFT: PI,
|
|
UP + LEFT: PI,
|
|
TOP + RIGHT: PI + HALF_PI,
|
|
UP + RIGHT: PI + HALF_PI,
|
|
}
|
|
|
|
def quarter_circle(x, y, radius, quadrant):
|
|
circle_arc(x, y, radius, ROTATION[quadrant], HALF_PI)
|
|
|
|
def half_circle(x, y, radius, quadrant):
|
|
circle_arc(x, y, radius, ROTATION[quadrant], PI)
|
|
|
|
def circle_arc(x, y, radius, start_ang, sweep_ang):
|
|
arc(x, y, radius * 2, radius * 2, start_ang, start_ang + sweep_ang)
|
|
|
|
def b_circle_arc(x, y, radius, start_ang, sweep_ang, mode=0):
|
|
b_arc(x, y, radius * 2, radius * 2, start_ang, start_ang + sweep_ang,
|
|
mode=mode)
|
|
|
|
def b_arc(cx, cy, w, h, start_angle, end_angle, mode=0):
|
|
"""
|
|
A bezier approximation of an arc
|
|
using the same signature as the original Processing arc()
|
|
mode: 0 "normal" arc, using beginShape() and endShape()
|
|
1 "middle" used in recursive call of smaller arcs
|
|
2 "naked" like normal, but without beginShape() and endShape()
|
|
for use inside a larger PShape
|
|
"""
|
|
theta = end_angle - start_angle
|
|
# Compute raw Bezier coordinates.
|
|
if mode != 1 or theta < HALF_PI:
|
|
x0 = cos(theta / 2.0)
|
|
y0 = sin(theta / 2.0)
|
|
x3 = x0
|
|
y3 = 0 - y0
|
|
x1 = (4.0 - x0) / 3.0
|
|
if y0 != 0:
|
|
y1 = ((1.0 - x0) * (3.0 - x0)) / (3.0 * y0) # y0 != 0...
|
|
else:
|
|
y1 = 0
|
|
x2 = x1
|
|
y2 = 0 - y1
|
|
# Compute rotationally-offset Bezier coordinates, using:
|
|
# x' = cos(angle) * x - sin(angle) * y
|
|
# y' = sin(angle) * x + cos(angle) * y
|
|
bezAng = start_angle + theta / 2.0
|
|
cBezAng = cos(bezAng)
|
|
sBezAng = sin(bezAng)
|
|
rx0 = cBezAng * x0 - sBezAng * y0
|
|
ry0 = sBezAng * x0 + cBezAng * y0
|
|
rx1 = cBezAng * x1 - sBezAng * y1
|
|
ry1 = sBezAng * x1 + cBezAng * y1
|
|
rx2 = cBezAng * x2 - sBezAng * y2
|
|
ry2 = sBezAng * x2 + cBezAng * y2
|
|
rx3 = cBezAng * x3 - sBezAng * y3
|
|
ry3 = sBezAng * x3 + cBezAng * y3
|
|
# Compute scaled and translated Bezier coordinates.
|
|
rx, ry = w / 2.0, h / 2.0
|
|
px0 = cx + rx * rx0
|
|
py0 = cy + ry * ry0
|
|
px1 = cx + rx * rx1
|
|
py1 = cy + ry * ry1
|
|
px2 = cx + rx * rx2
|
|
py2 = cy + ry * ry2
|
|
px3 = cx + rx * rx3
|
|
py3 = cy + ry * ry3
|
|
# Debug points... comment this out!
|
|
# stroke(0)
|
|
# ellipse(px3, py3, 15, 15)
|
|
# ellipse(px0, py0, 5, 5)
|
|
# Drawing
|
|
if mode == 0: # 'normal' arc (not 'middle' nor 'naked')
|
|
beginShape()
|
|
if mode != 1: # if not 'middle'
|
|
vertex(px3, py3)
|
|
if theta < HALF_PI:
|
|
bezierVertex(px2, py2, px1, py1, px0, py0)
|
|
else:
|
|
# to avoid distortion, break into 2 smaller arcs
|
|
b_arc(cx, cy, w, h, start_angle, end_angle - theta / 2.0, mode=1)
|
|
b_arc(cx, cy, w, h, start_angle + theta / 2.0, end_angle, mode=1)
|
|
if mode == 0: # end of a 'normal' arc
|
|
endShape()
|
|
|
|
def p_circle_arc(x, y, radius, start_ang, sweep_ang, mode=0, num_points=None):
|
|
p_arc(x, y, radius * 2, radius * 2, start_ang, start_ang + sweep_ang,
|
|
mode=mode, num_points=num_points)
|
|
|
|
def p_arc(cx, cy, w, h, start_angle, end_angle, mode=0, num_points=None):
|
|
"""
|
|
A poly approximation of an arc
|
|
using the same signature as the original Processing arc()
|
|
mode: 0 "normal" arc, using beginShape() and endShape()
|
|
2 "naked" like normal, but without beginShape() and endShape()
|
|
for use inside a larger PShape
|
|
"""
|
|
if not num_points:
|
|
num_points = 24
|
|
# start_angle = start_angle if start_angle < end_angle else start_angle - TWO_PI
|
|
sweep_angle = end_angle - start_angle
|
|
if mode == 0:
|
|
beginShape()
|
|
if sweep_angle < 0:
|
|
start_angle, end_angle = end_angle, start_angle
|
|
sweep_angle = -sweep_angle
|
|
angle = sweep_angle / int(num_points)
|
|
a = end_angle
|
|
while a >= start_angle:
|
|
sx = cx + cos(a) * w / 2.
|
|
sy = cy + sin(a) * h / 2.
|
|
vertex(sx, sy)
|
|
a -= angle
|
|
elif sweep_angle > 0:
|
|
angle = sweep_angle / int(num_points)
|
|
a = start_angle
|
|
while a <= end_angle:
|
|
sx = cx + cos(a) * w / 2.
|
|
sy = cy + sin(a) * h / 2.
|
|
vertex(sx, sy)
|
|
a += angle
|
|
else:
|
|
sx = cx + cos(start_angle) * w / 2.
|
|
sy = cy + sin(start_angle) * h / 2.
|
|
vertex(sx, sy)
|
|
if mode == 0:
|
|
endShape()
|