How to draw a dashed curved line with pygame? - python

I need to draw sine and cosine waves on a coordinate system exactly like in this picture. I did all the work well except I failed to represent dashed and curved line with pygame. I have smth similar to what I need, but how can I make it curved? Or how can I improve this to make it like pygame.draw.lines, not pygame.draw.line?
import pygame
import math
class Point:
# constructed using a normal tupple
def __init__(self, point_t = (0,0)):
self.x = float(point_t[0])
self.y = float(point_t[1])
# define all useful operators
def __add__(self, other):
return Point((self.x + other.x, self.y + other.y))
def __sub__(self, other):
return Point((self.x - other.x, self.y - other.y))
def __mul__(self, scalar):
return Point((self.x*scalar, self.y*scalar))
def __div__(self, scalar):
return Point((self.x/scalar, self.y/scalar))
def __len__(self):
return int(math.sqrt(self.x**2 + self.y**2))
# get back values in original tuple format
def get(self):
return (self.x, self.y)
def draw_dashed_line(surf, color, start_pos, end_pos, width=1, dash_length=4):
origin = Point(start_pos)
target = Point(end_pos)
displacement = target - origin
length = len(displacement)
slope = displacement.__div__(length)
for index in range(0, int(length/dash_length), 2):
start = origin + (slope * index * dash_length)
end = origin + (slope * (index + 1) * dash_length)
pygame.draw.line(surf, color, start.get(), end.get(), width)
pygame.init()
screen = pygame.display.set_mode((400, 300))
done = False
while not done:
draw_dashed_line(screen,(0,255,0),(0,0),(110,110))
for event in pygame.event.get():
if event.type == pygame.QUIT:
done = True
pygame.display.flip()

Write a function that operates similar as pygame.draw.line() but draws a dashed straight line. The function has an additional argument prev_line_len which indicates where the line segment is within a consecutive curve. Compute the Euclidean distance between the points and the Unit vector that points from the beginning of the line segment to its end. Distribute the strokes along the line:
def draw_dashed_line(surf, color, p1, p2, prev_line_len, dash_length=8):
dx, dy = p2[0]-p1[0], p2[1]-p1[1]
if dx == 0 and dy == 0:
return
dist = math.hypot(dx, dy)
dx /= dist
dy /= dist
step = dash_length*2
start = (int(prev_line_len) // step) * step
end = (int(prev_line_len + dist) // step + 1) * step
for i in range(start, end, dash_length*2):
s = max(0, start - prev_line_len)
e = min(start - prev_line_len + dash_length, dist)
if s < e:
ps = p1[0] + dx * s, p1[1] + dy * s
pe = p1[0] + dx * e, p1[1] + dy * e
pygame.draw.line(surf, color, pe, ps
Write another function that behaves similarly to pygame.draw.lines(), but uses the former function (draw_dashed_line) to draw the dashed curve. Calculate the length from the beginning of the curve to the beginning of each line segment and pass it to the function:
def draw_dashed_lines(surf, color, points, dash_length=8):
line_len = 0
for i in range(1, len(points)):
p1, p2 = points[i-1], points[i]
dist = math.hypot(p2[0]-p1[0], p2[1]-p1[1])
draw_dashed_line(surf, color, p1, p2, line_len, dash_length)
line_len += dist
Minimal example:
repl.it/#Rabbid76/DashedLine
import pygame
import math
def draw_dashed_line(surf, color, p1, p2, prev_line_len, dash_length=8):
dx, dy = p2[0]-p1[0], p2[1]-p1[1]
if dx == 0 and dy == 0:
return
dist = math.hypot(dx, dy)
dx /= dist
dy /= dist
step = dash_length*2
start = (int(prev_line_len) // step) * step
end = (int(prev_line_len + dist) // step + 1) * step
for i in range(start, end, dash_length*2):
s = max(0, start - prev_line_len)
e = min(start - prev_line_len + dash_length, dist)
if s < e:
ps = p1[0] + dx * s, p1[1] + dy * s
pe = p1[0] + dx * e, p1[1] + dy * e
pygame.draw.line(surf, color, pe, ps)
def draw_dashed_lines(surf, color, points, dash_length=8):
line_len = 0
for i in range(1, len(points)):
p1, p2 = points[i-1], points[i]
dist = math.hypot(p2[0]-p1[0], p2[1]-p1[1])
draw_dashed_line(surf, color, p1, p2, line_len, dash_length)
line_len += dist
pygame.init()
screen = pygame.display.set_mode((400, 300))
done = False
line = [(i, 150 + math.sin(math.radians(i*2)) * 100) for i in range(400)]
while not done:
for event in pygame.event.get():
if event.type == pygame.QUIT:
done = True
draw_dashed_lines(screen, (255, 255, 255), line)
pygame.display.flip()

Related

How to obtain the precise values of the streets of a city with OSMnx?

I want to make a traffic simulator of a city and for that I need to get the exact location of the streets and then plot them.
To draw the map I'm taking the streets of omsnx, but these have some flaws.Here I show how it looks like using the omsnx.plot_graph() function.
But using the values of G.edges() and building the graph myself there are inconsistencies like extra streets. This is an example of what the graph looks like using exactly the values provided by the edges.
Note that both images show the same traffic circle.
So the question is how to obtain the real street values without noise, i.e. without several streets playing the role of one.
This is the code I use to plot with pygame.
import osmnx as ox
address_name='Ciudad Deportiva, Havana, Cuba'
#Import graph
point = (23.1021, -82.3936)
G = ox.graph_from_point(point, dist=1000, retain_all=True, simplify=True, network_type='drive')
G = ox.project_graph(G)
import pygame
from map import Map
RED = (255, 0, 0)
BLUE = (0, 0, 20)
GRAY = (215,215,215)
WHITE = (255, 255, 255)
inc = 0.8
m = Map(1400, 800, lng=inc*2555299.469922482, lat=inc*356731.10053785384, i_zoom=0.1)
last_x = -1
last_y = -1
i=0
while True:
for event in pygame.event.get():
if event.type == pygame.MOUSEBUTTONDOWN:
if event.button == 4:
m.inc_zoom()
elif event.button == 5:
m.dec_zoom()
if event.type == pygame.MOUSEMOTION:
if event.buttons[0] == 1:
if last_x == last_y == -1:
last_x, last_y = event.pos
else:
m.x += (event.pos[0] - last_x)/2
m.y += (event.pos[1] - last_y)/2
last_x, last_y = event.pos
if event.type == pygame.MOUSEBUTTONUP:
if event.button == 1:
last_x = last_y = -1
m.fill(GRAY)
# Here I take the coordinates of the streets and paint them
for _, _, data in G.edges(data=True):
try:
m.draw_road(data['geometry'], inc, BLUE)
except:
pass
m.update()
Other functions and objects I use for plotting. This is the code of map.py
from typing import List, Tuple
from window import Window
from pygame import gfxdraw
from shapely.geometry import LineString
def build_rect(
start: Tuple[float,float],
end: Tuple[float,float],
width: float = 3
) -> List[Tuple[float,float]]:
x0, y0 = start
x1, y1 = end
if x0**2 + y0**2 > x1**2 + y1**2:
x0, y0 = end
x1, y1 = start
# vector from start to end
vX, vY = x1 - x0, y1 - y0
# normal vector
nX, nY = -vY, vX
# normalize
n = (nX**2 + nY**2)**0.5
nX, nY = width/n * nX, width/n * nY
# third vector
x2, y2 = x1 + nX, y1 + nY
# fourth vector
x3, y3 = x0 + nX, y0 + nY
return [(x0, y0), (x1, y1), (x2, y2), (x3, y3)]
class Map(Window):
def __init__(self, width, height, **kwargs):
super().__init__(width, height, **kwargs)
def draw_road(self, st: LineString, inc: float, color: Tuple[float,float,float]):
last = None
for c in st.__geo_interface__['coordinates']:
c = (inc*c[0], inc*c[1])
if last == None:
last = (c[0] - self.lat,c[1] - self.lng)
continue
lat = c[0] - self.lat
lng = c[1] - self.lng
pts = build_rect(last, (lat, lng))
gfxdraw.filled_polygon(self.screen, [
(self.x + lat * self.zoom, self.y + lng * self.zoom)
for lat, lng in pts
], color)
And this is the code of window.py.
import pygame
from pygame import gfxdraw
from pygame.locals import *
class Window:
def __init__(self, width, height, **kwargs):
self.width = width
self.height = height
self.zoom = 1
self.x = self.y = 0
self.i_zoom = 0.001
self.__dict__.update(kwargs)
pygame.init()
self.screen = pygame.display.set_mode((width, height))
def inc_zoom(self):
self.zoom += self.i_zoom
def dec_zoom(self):
self.zoom -= self.i_zoom
self.zoom = max(0, self.zoom)
def draw_polygon(self, points, color):
gfxdraw.filled_polygon(self.screen, [
(self.x + pt[0] * self.zoom, self.y + pt[1] * self.zoom)
for pt in points], color)
def fill(self, color):
self.screen.fill(color)
def update(self):
pygame.display.update()

Python 2d Raycaster not using proper depth [duplicate]

This question already has answers here:
How do I fix wall warping in my raycaster?
(1 answer)
Problem with recognising where a ray in raycaster intersects a wall along the horizontal axis
(1 answer)
cant get raycast to work from angles 90 to 270 pygame
(1 answer)
Why my raycasting keeps going through walls?
(1 answer)
Closed 3 months ago.
I am trying to create a raycast visualizer. The lines are supposed to shoot out and stop when they collide with a wall. Currently the length is entirely random and sometimes the rays point in directions that are even behind me. I am using an scale of 47 when i draw things to the screen for tiling purposes. I have tried for 10 or so hours every scale in the raycast code and I can't see what I am missing.
import pygame
import numpy
from PygameEngine import GameEngine
import sys
import math
class RayCasting:
FOV = numpy.pi/5
HALF_FOV = FOV/2
NUM_RAYS = GameEngine.WIDTH//2
HALF_NUM_RAYS = NUM_RAYS//2
DELTA_ANGLE = FOV/NUM_RAYS
MAX_DEPTH = 20
def __init__(self, game):
self.game = game
def rayCast(self):
ox, oy = self.game.wasd.pos
x_map = int(ox)
y_map = int(oy)
ray_angle = self.game.wasd.angle - self.HALF_FOV + 0.000001
for ray in range(self.NUM_RAYS):
sin_a = math.sin(ray_angle)
cos_a = math.cos(ray_angle)
# horizontals
y_hor, dy = (y_map + 1, 1) if sin_a > 0 else (y_map - 1e-6, -1)
depth_hor = (y_hor - oy) / sin_a
x_hor = ox + depth_hor * cos_a
delta_depth = dy / sin_a
dx = delta_depth * cos_a
print("YHor: ",y_hor, " DY:", dy, " Depth Hor: ", depth_hor, "X Hor: ", x_hor,
" Delta Depth: ", delta_depth, " DX: ", dx)
for i in range(self.MAX_DEPTH):
tile_hor = int(x_hor), int(y_hor)
if tile_hor in self.game.MAP.wallMap:
# print("INSIDE HOR")
break
x_hor += dx
y_hor += dy
depth_hor += delta_depth
# verticals
x_vert, dx = (x_map + 1, 1) if cos_a > 0 else (x_map - 1e-6, -1)
depth_vert = (x_vert - ox) / cos_a
y_vert = oy + depth_vert * sin_a
delta_depth = dx / cos_a
dy = delta_depth * sin_a
for i in range(self.MAX_DEPTH):
tile_vert = int(x_vert), int(y_vert)
if tile_vert in self.game.MAP.wallMap:
# print("INSIDE VERT")
break
x_vert += dx
y_vert += dy
depth_vert += delta_depth
# depth, texture offset
if depth_vert < depth_hor:
depth = depth_vert
#y_vert %= 1
#offset = y_vert if cos_a > 0 else (1 - y_vert)
else:
depth = depth_hor
#x_hor %= 1
#offset = (1 - x_hor) if sin_a > 0 else x_hor
# remove fishbowl effect
#depth *= math.cos(self.game.wasd.angle - ray_angle)
# projection
#proj_height = SCREEN_DIST / (depth + 0.0001)
# ray casting result
#self.ray_casting_result.append((depth, proj_height, texture, offset))
ray_angle += self.DELTA_ANGLE
pygame.draw.line(self.game.screen, "yellow", (ox*self.game.CELLSIZE,oy*self.game.CELLSIZE), (ox*self.game.CELLSIZE+depth*cos_a, oy*self.game.CELLSIZE+depth*sin_a), 1)
def update(self):
self.rayCast()
from PygameEngine import GameEngine
from Circle import Circle
import pygame
from pygame.locals import *
import sys
import numpy
from map import Map
from RaycastFunction import RayCasting
class RaycastGame(GameEngine):
# Space bar to place this circle which will connect to the WASD with a line
planet = Circle((0,0,0))
planet.keyX = 5
planet.keyY = 5
# Grid set up
def __init__(self):
super().__init__()
self.load()
self.MAP = Map()
self.CELLSIZE = self.MAP.CELLSIZE
# Circle controllable with WASD
self.wasd = Circle((123, 255, 123))
self.raycast = RayCasting(self)
def DDA(self):
# -
# * |
# Remember the Plane is - --m-- +
# * = target |
# m = mouse +
distX = self.wasd.keyX - self.planet.pos[0]
distY = self.wasd.keyY - self.planet.pos[1]
#hypotenuse = numpy.sqrt(distX**2+distY**2)
theta = numpy.arctan((distY/(distX+.0001)))
theta += numpy.deg2rad(90)
# print(numpy.rad2deg(theta), " THETA")
collisionPos = (0,0)
def draw(self):
# Draw MAP array
self.MAP.drawMap()
self.MAP.drawGrid()
# Draw mouse character
#pygame.draw.circle(self.screen, (0, 0, 0),
#(self.plane), Circle.radius)
# Draw planet
# self.planet.draw(self.screen)
# Draw wasd character
self.wasd.draw(self.screen)
# Connect mouse and wasd characters with a line
#pygame.draw.line(self.screen, (255, 255, 255), self.planet.pos, (self.wasd.keyX, self.wasd.keyY), 5)
def update(self):
self.planet.placePlanet()
self.wasd.move()
self.DDA()
self.raycast.update()
def run(self):
# Game loop.
while True:
#This gets written over. Only for clearing screen before each draw
self.screen.fill((0, 0, 0))
for event in pygame.event.get():
if event.type == QUIT:
pygame.quit()
sys.exit()
# Update.
self.update()
# Draw
self.draw()
pygame.display.flip()
self.fpsClock.tick(self.FPS)
I do not understand why the rays are not stopping in the proper area.

Coulombs Law: Protons atract each other

I'am working on a simulation of the Coulomb's Law with pygame, but I have a problem. When I start the Simulation an set two Protons, they attract each other. But there is more!
When I set an electron and a proton, they both start to "travel" with a constant distance to each other in the same direction.
Here is my code:
import pygame
import numpy as np
import math
pygame.init()
# window-settings
WIDTH, HEIGHT = 800, 800
WIN = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption("Electric field simulation")
# constants
Pi = np.pi
epsilon0 = 8.85 * (10**(-12))
q = 1.6 * (10**-19)
# colors
WHITE = (255,255,255)
BLACK = (0,0,0)
BLUE = (100, 149, 237)
RED = (188, 39, 50)
class Charge:
TIMESTEP = 50000
def __init__(self, x, y, radius, color, q):
self.x = x
self.y = y
self.radius = radius
self.color = color
self.q = q
self.x_vel = 0
self.y_vel = 0
def draw(self, win):
pygame.draw.circle(win, self.color, (self.x, self.y), self.radius)
def attraction(self, other):
other_x, other_y = other.x, other.y
distance_x = other_x - self.x
distance_y = other_y - self.y
distance = math.sqrt(distance_x ** 2 + distance_y ** 2)
force = (1 / (4 * Pi * epsilon0)) * self.q * other.q / (distance ** 2)
theta = math.atan2(distance_y, distance_x)
force_x = math.cos(theta) * force
force_y = math.sin(theta) * force
return force_x, force_y
def update_position(self, charges):
total_fx = total_fy = 0
for charge in charges:
if self == charge:
continue
fx, fy = self.attraction(charge)
total_fx += fx
total_fy += fy
self.x_vel += total_fx / self.q * self.TIMESTEP
self.y_vel += total_fy / self.q * self.TIMESTEP
self.x += self.x_vel * self.TIMESTEP
self.y += self.y_vel * self.TIMESTEP
def main():
run = True
clock = pygame.time.Clock()
proton = Charge(200, 200, 10, RED, q)
electron = Charge(300, 200, 10, BLUE, -q)
charges = [electron, proton]
while run:
clock.tick(60)
WIN.fill(WHITE)
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if event.type == pygame.MOUSEBUTTONDOWN: # To set charges
if event.button == 1: # Sets positive charge
charges.append(Charge(pygame.mouse.get_pos()[0], pygame.mouse.get_pos()[1], 10, RED, q))
if event.button == 3: # Sets negitive charge
charges.append(Charge(pygame.mouse.get_pos()[0], pygame.mouse.get_pos()[1], 10, BLUE, -q))
for charge in charges:
charge.update_position(charges)
charge.draw(WIN)
pygame.display.update()
pygame.quit()
if __name__ == "__main__":
main()
I think the problem is the attraction-function, but I don't know how to solve it.
At the moment I have not the possibility to run your code but have you mixed up the direction of your force?
At least Wikipedia calculates r1-r2
Annother source of error might be the sin, cos etc. functions have you checked for your example that the calculated values are correct?
If I understand your code correct you update all positions one after eachother and apply the changes right away. Dependend on your application you might want to
Calculate all forces
Update all Values
Otherwise you have a multiple states of your system in just one time step.
Okay I solved the problem by calculating the direction of the force. With this I calculate at first the the force but return the absolute and then calculate the direction and speed.
Here is the code of my changes (I just changed something in the updating and attracting function):
def attraction(self, other):
other_x, other_y = other.x, other.y
distance_x = self.x - other_x
distance_y = self.y - other_y
distance = math.sqrt(distance_x ** 2 + distance_y ** 2)
if self.q != other.q and distance < 5:
return 0,0
force = (1 / (4 * Pi * epsilon0)) * self.q * other.q / (distance ** 2)
force_x = distance_x / distance*np.abs(force)
force_y = distance_y / distance*np.abs(force)
return force_x, force_y
def update_position(self, charges):
total_fx = total_fy = 0
for charge in charges:
if self == charge:
continue
fx, fy = self.attraction(charge)
total_fx += fx
total_fy += fy
self.x_vel += total_fx / self.q * self.TIMESTEP
self.y_vel += total_fy / self.q * self.TIMESTEP
if self != charge and self.q < 0 and self.q != charge.q:
x = abs(self.x - charge.x)
y = abs(self.y - charge.y)
self.direction = [x / np.sqrt((x ** 2) + (y ** 2)),y / np.sqrt((x ** 2) + (y ** 2))]
elif self != charge and self.q > 0 and self.q != charge.q:
x = abs(self.x - charge.x)
y = abs(self.y - charge.y)
self.direction = [-x / np.sqrt((x ** 2) + (y ** 2)), -y / np.sqrt((x ** 2) + (y ** 2))]
elif self != charge and self.q < 0 and self.q == charge.q:
x = abs(self.x - charge.x)
y = abs(self.y - charge.y)
self.direction = [-x / np.sqrt((x ** 2) + (y ** 2)), -y / np.sqrt((x ** 2) + (y ** 2))]
elif self != charge and self.q > 0 and self.q == charge.q:
x = abs(self.x - charge.x)
y = abs(self.y - charge.y)
self.direction = [x / np.sqrt((x ** 2) + (y ** 2)), y / np.sqrt((x ** 2) + (y ** 2))]
self.x += self.x_vel * self.TIMESTEP * self.direction[0]
self.y += self.y_vel * self.TIMESTEP * self.direction[1]
I know this code isn't that beautiful, but at first it works.

Pygame: How do I apply Separating Axis Theorem (SAT) to Rotating Squares?

I don't want the code (I really do want the code), but can someone explain to me how I can create the diagonal line to see if there's a gap? I know we have to use vectors, but I don't know how to do that using python
So, using the logic of Separating Axis Theorem that if you cant draw a line in between 2 squares then they are overlapping and colliding. I made something close, its not perfect but its close, I also haven't accounted for rotation of squares but if you find a way to find the vertices/corners of the square, then this could easily work. The way i did it was that i turned the squares into lines and drew a line directly in the middle of the squares and at the normal of the line in between the squares, its a bit confusing but it makes sense once you see it. I then used line intersecting maths to find if they intersect.
import pygame
from pygame.locals import *
from pygame import Vector2
pygame.init()
screen = pygame.display.set_mode((500,500))
#check if 2 lines are intersecting
def LineIntersect(line1, line2):
#the math is from wikipedia
x1 = line1[0].x
y1 = line1[0].y
x2 = line1[1].x
y2 = line1[1].y
x3 = line2[0].x
y3 = line2[0].y
x4 = line2[1].x
y4 = line2[1].y
den = (x1 - x2) * (y3 - y4) - (y1 - y2) * (x3 - x4)
if den == 0:
return
t = ((x1 - x3) * (y3 - y4) - (y1 - y3) * (x3 - x4)) / den
u = -((x1 - x2) * (y1 - y3) - (y1 - y2) * (x1 - x3)) / den
if t > 0 and t < 1 and u > 0 and u < 1:
pt = Vector2()
pt.x = x1 + t * (x2 - x1)
pt.y = y1 + t * (y2 - y1)
return pt
return
#class for sqaure
class square:
def __init__(self,x,y,w):
self.x = x
self.y = y
self.w = w
self.centerx = self.x + w//2
self.centery = self.y + w//2
self.col = (255,0,0)
def Draw(self, outline = False):
if outline:
self.Outline()
else:
pygame.draw.rect(screen,self.col,(self.x,self.y,self.w,self.w))
def Outline(self):
for point1, point2 in self.Lines():
pygame.draw.line(screen,sqr2.col,point1,point2,1)
#get the lines that make up the square, the outline/perameter
def Lines(self):
lines = []
lines.append((Vector2(self.x,self.y),Vector2(self.x+self.w,self.y)))
lines.append((Vector2(self.x,self.y),Vector2(self.x,self.y + self.w)))
lines.append((Vector2(self.x + self.w,self.y + self.w),Vector2(self.x+self.w,self.y)))
lines.append((Vector2(self.x + self.w,self.y + self.w),Vector2(self.x,self.y + self.w)))
return lines
#draw a line inbetween the 2 squares
def DrawLineInBetween():
#draw a line between the 2 squares, get gradient
#to avoid divide by zero
if abs(sqr1.x - sqr2.x) == 0:
gradient = "infinity"
else:
#rise over run
#left - right = run
left = sqr1 if sqr1.x < sqr2.x else sqr2
right = sqr1 if left == sqr2 else sqr2
gradient = ((left.y - right.y)/abs(sqr1.x - sqr2.x))
#print("gradient:",gradient)
#get the middle point between the centers of the squares
middle = (max(sqr1.x + sqr1.w//2, sqr2.x + sqr2.w//2) - abs(sqr1.x - sqr2.x)//2,
max(sqr1.y + sqr1.w//2, sqr2.y + sqr2.w//2) - abs(sqr1.y - sqr2.y)//2)
#to avoid divide by 0
if gradient == 0:
point1 = Vector2(middle[0], middle[1] + 100)
point2 = Vector2(middle[0], middle[1] - 100)
elif gradient == "infinity":
point1 = Vector2(middle[0] - 100, middle[1])
point2 = Vector2(middle[0] + 100, middle[1])
else:
#get normal of line
gradient = -1/gradient
#print("normal:",gradient)
point1 = Vector2(middle[0] + 100, middle[1] + int(-100 * gradient))
point2 = Vector2(middle[0] - 100, middle[1] + int(100 * gradient))
#print(point1)
#print(point2)
#print(middle)
pygame.draw.line(screen,(0,255,0),point1,point2,1)
line = (point1, point2)
return line
sqr1 = square(100,100,50)
sqr2 = square(200,100,50)
Clock = pygame.time.Clock()
running = True
key = ""
while running:
screen.fill((0,0,0))
sqr1.Draw(outline=True)
sqr2.Draw()
line = DrawLineInBetween()
for sqr_line in sqr1.Lines():
pt = LineIntersect(line,sqr_line)
if pt:
pygame.draw.circle(screen,(0,255,255),(int(pt.x),int(pt.y)),5)
if key == "s":
sqr1.y += 1
elif key == "w":
sqr1.y -= 1
if key == "d":
sqr1.x += 1
if key == "a":
sqr1.x -= 1
pygame.display.update()
Clock.tick(60)
for e in pygame.event.get():
if e.type == pygame.QUIT:
pygame.quit()
running = False
if e.type == MOUSEBUTTONDOWN:
print(e.pos)
if e.type == KEYDOWN:
key = e.unicode
if e.type == KEYUP:
key = ""
doing rotating squares:
added rotation variable in square class, i used this answer to find the corners of the square, then once i have the corners, used the line intersetion.
Here is new class:
#class for sqaure
class square:
def __init__(self,x,y,w):
self.x = x
self.y = y
self.w = w
self.centerx = self.x + w//2
self.centery = self.y + w//2
self.col = (255,0,0)
self.rotation_angle = 0
def Draw(self, outline = False):
if outline:
self.Outline()
else:
pygame.draw.rect(screen,self.col,(self.x,self.y,self.w,self.w))
#this used the normal coordinate of an unrotated square to find new coordinates of rotated sqaure
def GetCorner(self,tempX,tempY):
angle = math.radians(self.rotation_angle)
rotatedX = tempX*math.cos(angle) - tempY*math.sin(angle);
rotatedY = tempX*math.sin(angle) + tempY*math.cos(angle);
x = rotatedX + self.centerx;
y = rotatedY + self.centery;
return Vector2(x,y)
def Outline(self):
for point1, point2 in self.Lines():
pygame.draw.line(screen,sqr2.col,point1,point2,1)
#new lines method, only changed to GetCorner()
def Lines(self):
lines = []
top_left = self.GetCorner(self.x - self.centerx, self.y - self.centery)
top_right = self.GetCorner(self.x + self.w - self.centerx, self.y - self.centery)
bottom_left = self.GetCorner(self.x - self.centerx, self.y + self.w - self.centery)
bottom_right = self.GetCorner(self.x + self.w - self.centerx, self.y + self.w - self.centery)
lines.append((top_left,top_right))
lines.append((top_left,bottom_left))
lines.append((bottom_right,top_right))
lines.append((bottom_right,bottom_left))
return lines
#chnaged to this as rotation rotates around center, so need to update both x and centerx
def Move(self,x =None, y = None):
if x:
self.x += x
self.centerx += x
if y:
self.y += y
self.centery += y
#get the lines that make up the square, the outline/perameter
#def Lines(self):
#lines = []
#lines.append((Vector2(self.x,self.y),Vector2(self.x+self.w,self.y)))
#lines.append((Vector2(self.x,self.y),Vector2(self.x,self.y + self.w)))
#lines.append((Vector2(self.x + self.w,self.y + self.w),Vector2(self.x+self.w,self.y)))
#lines.append((Vector2(self.x + self.w,self.y + self.w),Vector2(self.x,self.y + self.w)))
#return lines

How to draw a Spiral & Arc Shape Curves using pygame? [duplicate]

I am trying to make realistic water in pygame:
This is till now my code:
from random import randint
import pygame
WIDTH = 700
HEIGHT = 500
win = pygame.display.set_mode((WIDTH, HEIGHT))
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)
AQUA = 'aqua'
RADIUS = 1
x, y = 0, HEIGHT//2
K = 1
FORCE = 100
VELOCITY = 0.5
run = True
class Molecule:
def __init__(self, x, y, radius, force, k):
self.x = x
self.y = y
self.radius = radius
self.force = force
self.k = k
self.max_amplitude = y + force/k
self.min_amplitude = y - force/k
self.up = False
self.down = True
self.restore = False
def draw(self, win):
pygame.draw.circle(win, BLACK, (self.x, self.y), self.radius)
def oscillate(self):
if self.y <= self.max_amplitude and self.down == True:
self.y += VELOCITY
if self.y == self.max_amplitude or self.up:
self.up = True
self.down = False
self.y -= VELOCITY
if self.y == self.min_amplitude:
self.up = False
self.down = True
molecules = []
for i in range(100):
FORCE = randint(10, 20)
molecules.append(Molecule(x, y, RADIUS, FORCE, K))
x += 10
while run:
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
win.fill(WHITE)
for molecule in molecules:
molecule.draw(win)
molecule.oscillate()
for i in range(len(molecules)):
try:
pygame.draw.line(win, BLACK, (molecules[i].x, molecules[i].y), (molecules[i+1].x, molecules[i+1].y))
pygame.draw.line(win, AQUA, (molecules[i].x, molecules[i].y), (molecules[i+1].x, HEIGHT))
except:
pass
pygame.display.flip()
pygame.quit()
But as may expected the water curve is not smooth:
Look at it:
Sample Img1
I want to connect the two randomly added wave points using a set of circles not line like in this one so that a smooth curve could occur.
And in this way i could add the water color to it such that it will draw aqua lines or my desired color line from the point to the end of screen and all this will end up with smooth water flowing simulation.
Now the question is how could i make the points connect together smoothly into a smooth curve by drawing point circles at relative points?
I suggest sticking the segments with a Bézier curves. Bézier curves can be drawn with pygame.gfxdraw.bezier
Calculate the slopes of the tangents to the points along the wavy waterline:
ts = []
for i in range(len(molecules)):
pa = molecules[max(0, i-1)]
pb = molecules[min(len(molecules)-1, i+1)]
ts.append((pb.y-pa.y) / (pb.x-pa.x))
Use the the tangents to define 4 control points for each segment and draw the curve with pygame.gfxdraw.bezier:
for i in range(len(molecules)-1):
p0 = molecules[i].x, molecules[i].y
p3 = molecules[i+1].x, molecules[i+1].y
p1 = p0[0] + 10, p0[1] + 10 * ts[i]
p2 = p3[0] - 10, p3[1] - 10 * ts[i+1]
pygame.gfxdraw.bezier(win, [p0, p1, p2, p3], 4, BLACK)
Complete example:
from random import randint
import pygame
import pygame.gfxdraw
WIDTH = 700
HEIGHT = 500
win = pygame.display.set_mode((WIDTH, HEIGHT))
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)
AQUA = 'aqua'
RADIUS = 1
x, y = 0, HEIGHT//2
K = 1
FORCE = 100
VELOCITY = 0.5
class Molecule:
def __init__(self, x, y, radius, force, k):
self.x = x
self.y = y
self.radius = radius
self.force = force
self.k = k
self.max_amplitude = y + force/k
self.min_amplitude = y - force/k
self.up = False
self.down = True
self.restore = False
def draw(self, win):
pygame.draw.circle(win, BLACK, (self.x, self.y), self.radius)
def oscillate(self):
if self.y <= self.max_amplitude and self.down == True:
self.y += VELOCITY
if self.y == self.max_amplitude or self.up:
self.up = True
self.down = False
self.y -= VELOCITY
if self.y == self.min_amplitude:
self.up = False
self.down = True
molecules = []
for i in range(50):
FORCE = randint(10, 20)
molecules.append(Molecule(x, y, RADIUS, FORCE, K))
x += 20
clock = pygame.time.Clock()
run = True
while run:
clock.tick(100)
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
win.fill(WHITE)
for molecule in molecules:
molecule.draw(win)
molecule.oscillate()
ts = []
for i in range(len(molecules)):
pa = molecules[max(0, i-1)]
pb = molecules[min(len(molecules)-1, i+1)]
ts.append((pb.y-pa.y) / (pb.x-pa.x))
for i in range(len(molecules)-1):
p0 = molecules[i].x, molecules[i].y
p3 = molecules[i+1].x, molecules[i+1].y
p1 = p0[0] + 10, p0[1] + 10 * ts[i]
p2 = p3[0] - 10, p3[1] - 10 * ts[i+1]
pygame.gfxdraw.bezier(win, [p0, p1, p2, p3], 4, BLACK)
for i in range(len(molecules)-1):
pygame.draw.line(win, AQUA, (molecules[i].x, molecules[i].y), (molecules[i].x, HEIGHT))
pygame.display.flip()
pygame.quit()
If you want to "fill" the water, you must calculate the points along the Bézier line and draw a filled polygon. How to calculate a Bézier curve is explained in Trying to make a Bezier Curve on PyGame library How Can I Make a Thicker Bezier in Pygame? and "X". You can use the following function:
def ptOnCurve(b, t):
q = b.copy()
for k in range(1, len(b)):
for i in range(len(b) - k):
q[i] = (1-t) * q[i][0] + t * q[i+1][0], (1-t) * q[i][1] + t * q[i+1][1]
return round(q[0][0]), round(q[0][1])
def bezier(b, samples):
return [ptOnCurve(b, i/samples) for i in range(samples+1)]
Use the bezier to stitch the wavy water polygon:
ts = []
for i in range(len(molecules)):
pa = molecules[max(0, i-1)]
pb = molecules[min(len(molecules)-1, i+1)]
ts.append((pb.y-pa.y) / (pb.x-pa.x))
pts = [(WIDTH, HEIGHT), (0, HEIGHT)]
for i in range(len(molecules)-1):
p0 = molecules[i].x, molecules[i].y
p3 = molecules[i+1].x, molecules[i+1].y
p1 = p0[0] + 10, p0[1] + 10 * ts[i]
p2 = p3[0] - 10, p3[1] - 10 * ts[i+1]
pts += bezier([p0, p1, p2, p3], 4)
Draw the polygon with pygame.draw.polygon():
pygame.draw.polygon(win, AQUA, pts)
Complete example:
from random import randint
import pygame
class Node:
def __init__(self, x, y, force, k, v):
self.x = x
self.y = y
self.y0 = y
self.force = force
self.k = k
self.v = v
self.direction = 1
def oscillate(self):
self.y += self.v * self.direction
if self.y0 - self.force / self.k > self.y or self.y0 + self.force / self.k < self.y:
self.direction *= -1
def draw(self, surf):
pygame.draw.circle(surf, "black", (self.x, self.y), 3)
window = pygame.display.set_mode((700, 500))
clock = pygame.time.Clock()
width, height = window.get_size()
no_of_nodes = 25
dx = width / no_of_nodes
nodes = [Node(i*dx, height//2, randint(15, 30), 1, 0.5) for i in range(no_of_nodes+1)]
def ptOnCurve(b, t):
q = b.copy()
for k in range(1, len(b)):
for i in range(len(b) - k):
q[i] = (1-t) * q[i][0] + t * q[i+1][0], (1-t) * q[i][1] + t * q[i+1][1]
return round(q[0][0]), round(q[0][1])
def bezier(b, samples):
return [ptOnCurve(b, i/samples) for i in range(samples+1)]
run = True
while run:
clock.tick(100)
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
for molecule in nodes:
molecule.oscillate()
ts = []
for i in range(len(nodes)):
pa = nodes[max(0, i-1)]
pb = nodes[min(len(nodes)-1, i+1)]
ts.append((pb.y-pa.y) / (pb.x-pa.x))
pts = [(width, height), (0, height)]
for i in range(len(nodes)-1):
p0 = nodes[i].x, nodes[i].y
p3 = nodes[i+1].x, nodes[i+1].y
p1 = p0[0] + 10, p0[1] + 10 * ts[i]
p2 = p3[0] - 10, p3[1] - 10 * ts[i+1]
pts += bezier([p0, p1, p2, p3], 4)
window.fill("white")
pygame.draw.polygon(window, 'aqua', pts)
for molecule in nodes:
molecule.draw(window)
pygame.display.flip()
pygame.quit()
exit()

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