quickreference.txt

# right-click + drag to pan around

# constructing MathObjects
v = Vector(3,4)     # 2d vector (dx,dy)
p = Point(3,4)      # 2d point (x,y)

polyline = Polyline([(0,0), (1,1), (2,2)])  # list of points
polygon = Polygon([(0,0), (1,1), (2,2)])    # list of points
rectangle = Polygon.rectangle(0,0,5,5)      # (x,y,width,height)
square = Polygon.square(0,0,1)              # (x,y,sides)
triangle = Polygon.triangle(0,0,3,3)        # (x,y,width,height)
circle = Polygon.circle(0,0,5)              # (x,y,radius)

# 2d linear transformation matrix:
# [a b]
# [c d]
T = LinearT([[a,b],[c,d]])  # create manually
T = LinearT.identity()      # identity matrix
T = LinearT.rotation(45)    # rotation matrix (degrees)
T = LinearT.scaling(2)      # scaling matrix
a, b = T.a, T.b             # get matrix components

# 2d affine transformation matrix
# [a b c]
# [d e f]
# [0 0 1]
T = AffineT([[a,b,c],[d,e,f]])  # create manually
T = AffineT.identity()          # identity matrix
T = AffineT.rotation(45)        # rotation matrix (degrees)
T = AffineT.scaling(2)          # scaling matrix
a, b = T.a, T.b                 # get matrix components

# vector operations
v = 3*v             # vector scaling
v = v + v           # vector addition
scaler = v.dot(v2)  # dot product
dx, dy = v.dx, v.dy # vector components
mag = v.mag         # vector magnitude
v.angle             # vector angle (degrees)
v.position          # position of the tail

# point operations
p = p + v       # point translation by vector
x, y = p.x, p.y # point components

# matrix operations
v = T * v               # matrix vector multiplication (transform vector)
p = T * p               # matrix point multiplication (transform point)
p = T * (3,4)           # matrix tuple multiplication (transform tuple)
T = T2 * T3             # matrix-matrix multiplication (compose transformations)
T = T**-1               # inverse transformation
polygon = T * polygon   # transform polygon

# all objects (vectors, points, polygons, matrices, etc) have the following functionality
obj.label = 'label'     # set label for the object
obj.color = 'red'       # set color for the object
draw(obj)               # draw object
draw(obj1, obj2, obj3)  # draw multiple objects in one call
clear(obj)              # erase object (i.e. undraw)
clear(obj1,obj2,obj3)   # erase multiple objects in one call
obj2 = obj.copy()       # copy object

# do something every frame (dt is time since last frame)
def on_update(dt):
    v.angle += dt * 5 # rotate vector v 5 degrees per second

# options
options.grid = False     # hide/show grid

# print stuff to console
print(stuff) # stuff can be any object or literal