def render(self):
"Render the vector as an arrow on a pygame.Surface"
l = self.length() * self.canvas.unit
if l < 2:
return Image((1, 1), self.stroke).image
shape = self.arrowShape
if type(shape) is dict:
if shape["fixed"]:
shape = shape.copy()
shape["width"] /= l
shape["head"] /= l
del shape["fixed"]
a = Arrow(l, **shape).config(fill=self.fill,
stroke=self.stroke,
weight=self.weight)
else:
dx, dy = shape
cv = Canvas((l, 2 * dy))
y = cv.center[1]
cv += Line((0, y), (l, y)).config(stroke=self.stroke,
weight=self.weight)
cv += Line((l - dx, y - dy), (l, y)).config(stroke=self.stroke,
weight=self.weight)
cv += Line((l - dx, y + dy), (l, y)).config(stroke=self.stroke,
weight=self.weight)
a = cv.snapshot()
return a.image
def axis(self, x=None, y=None, **kwargs):
"Draw coordinate axes"
style = {"weight": 2, "stroke": "black"}
style.update(kwargs)
px = self.px
if y is None and len(x) == 4:
x, y = x[:2], x[2:]
if x: self += Line(px(x[0], 0), px(x[1], 0)).config(**style)
if y: self += Line(px(0, y[0]), px(0, y[1])).config(**style)
return self
def gridlines(self, lrbt, step=1, axis=None, **kwargs):
"Draw gridlines and optional coordinate axes"
style = {"weight": 1, "stroke": "lightgrey"}
style.update(kwargs)
if type(step) in (int, float): dx = dy = step
else: dx, dy = step
x0, x1, y0, y1 = lrbt
px = self.px
if dx:
x = x0
while x < x1 + dx / 2:
self += Line(px(x, y0), px(x, y1)).config(**style)
x += dx
if dy:
while y0 < y1 + dy / 2:
self += Line(px(x0, y0), px(x1, y0)).config(**style)
y0 += dy
return self if axis is None else self.axis(lrbt, **axis)
def drawLot(self):
px = self.px
self += Line(px(-2.7, 0), px(2.7, 0)).config(weight=10, stroke="blue")
attr = dict(stroke="orange", weight=4)
for x in range(-2, 3):
self += Line(px(x, 2), px(x, 1)).config(**attr)
self += Line(px(x, -2), px(x, -1)).config(**attr)
self.flatten()
img = Circle(0.4 * self.unit).config(fill="grey", weight=0).snapshot()
for x in range(-3, 3):
self += Sprite(img).config(pos=px(x + 0.5, 2.36),
mass=50,
drag=0.02,
wrap=0)
self += Sprite(img).config(pos=px(x + 0.5, -2.37),
mass=50,
drag=0.02,
wrap=0)
return self
def _distToWall(pos, angle, sWidth, w, h):
"Calculate the distance to the sketch walls in the specified direction"
walls = Polygon([(0, 0), (w, 0), (w, h), (0, h)])
w += h
pts = []
for n in (-1, 0, 1):
v = vec2d(w, angle + n * sWidth)
line = Line(pos, vector=v)
pts.extend(walls.intersect(line))
return min(dist(pos, pt) for pt in pts) if len(pts) else None
def setup(game):
"Create Tic-Tac-Toe board with 100 pixel squares and 20 pixel margins"
# Load costumes for X and O sprites, and logo
img = Image(resolvePath("img/xo.png", __file__)).tiles(3)
game.alien = Image.fromBytes(sc8prData("alien")).config(height=36)
# Create and position sprites, one per square
for s in range(9):
pos = 70 + 100 * (s % 3), 70 + 100 * (s // 3)
game += Sprite(img).bind(contains=Graphic.contains,
onclick=clickSquare).config(pos=pos, width=100)
# Draw the board and start game
for pts in [((20,120), (320,120)), ((20,220), (320,220)),
((120,20), (120,320)), ((220,20), (220,320))]: game += Line(*pts)
startGame(game)
def setup(self):
self.caption = "Electric Force Simulation"
w, h = self.size
y = h - 40
x = w / 1.5
pivot = x, y - 200
self["string"] = Line(pivot, (x, y)).config(weight=3)
self += Charge().config(pos=(x, y))
self["blue"] = QCircle(60).config(
fill="blue").snapshot().bind(ondrag).config(pos=(40, y), height=24)
self["angle"] = Text().config(
pos=pivot, anchor=TOPRIGHT, font=MONO,
color="red").config(height=24).bind(ondrag)
self += Ruler(self.scale).config(pos=self.center)
msg = "Red Sphere\n m = {:.2f} g\n q = {:.0f} nC\n\nBlue Sphere\n q = {:.0f} nC"
msg = msg.format(self.mass, 1000 * self.q1, 1000 * self.q2)
self += MessageBox(msg, buttons="Close", fontSize=14,
font=MONO).bind(ondrag).config(pos=(8, 8),
anchor=TOPLEFT)
def __init__(self, scale=10, size=50, step=5, unit=("cm", 2), **cfg):
if "bg" not in cfg: cfg["bg"] = Image(bg="#e0e0f0a0")
if "weight" not in cfg: cfg["weight"] = 1
coord = lambda x: (x + 1) * scale
h = 3.5 * scale
super().__init__((coord(size + 1), h))
self.config(**cfg)
x = 0
cfg = dict(anchor=BOTTOM, font=MONO, fontStyle=BOLD, color="#000000a0")
while x <= size:
self += Text(x).config(pos=(coord(x), h - 1), **cfg)
x += step
if unit:
self += Text(unit[0]).config(pos=(coord(unit[1]), h - 1), **cfg)
x = 0
while x <= size:
s = coord(x)
self += Line((s, 0), (s, scale / (2 if x % step else 1)))
x += 1
for t in self:
if isinstance(t, Text): t.config(height=h / 2)
self.bind(ondrag)