0209a

2020/sketch_2020_02_09a/line_geometry.py

@@ -0,0 +1,146 @@
+
+def create_points(non_intersecting=True):
+    background(200)
+    done = False
+    while not done:
+        poly_points = [PVector(random(BORDER, width - BORDER),
+                               random(BORDER, height - BORDER)
+                               )
+                       for _ in range(NUM)]
+        ed = edges(poly_points)
+        done = True
+        if non_intersecting:
+            for p1, p2 in ed[::-1]:
+                for p3, p4 in ed[2::]:
+                    # test only non consecutive edges
+                    if (p1 != p3) and (p2 != p3) and (p1 != p4):
+                        if line_instersect(Line(p1, p2), Line(p3, p4)):
+                            done = False
+                            break
+    return poly_points
+     
+def is_inside(x, y, poly_points):   
+    min_, max_ = min_max(poly_points)
+    if x < min_.x or y < min_.y or x > max_.x or y > max_.y:
+        return False
+    
+    a = PVector(x, min_.y)
+    b = PVector(x, max_.y)
+    v_lines = inter_lines(Line(a, b), poly_points)
+    if not v_lines:
+        return False
+        
+    a = PVector(min_.x, y)
+    b = PVector(max_.x, y)
+    h_lines = inter_lines(Line(a, b), poly_points)
+    if not h_lines:
+        return False
+                
+    for v in v_lines:
+        for h in h_lines:
+            if line_instersect(v, h):
+                return True   
+                         
+    return False
+
+
+def inter_lines(L, poly_points):
+    inter_points = []
+    for p1, p2 in edges(poly_points):
+        inter = line_instersect(Line(p1, p2), L)
+        if inter:
+            inter_points.append(inter)
+    if  not inter_points:
+        return []
+    inter_lines = []
+    if len(inter_points) > 1:
+        inter_points.sort()
+        pairs = zip(inter_points[::2], inter_points[1::2])
+        for p1, p2 in pairs:
+            if p2:
+                inter_lines.append(Line(PVector(p1.x, p1.y),
+                                        PVector(p2.x, p2.y))) 
+    return inter_lines
+
+        
+class Line():
+    """ I should change this to a named tuple... """
+    def __init__(self, p1, p2):
+        self.p1 = p1
+        self.p2 = p2
+        
+    def plot(self):
+        line(self.p1.x, self.p1.y, self.p2.x, self.p2.y)
+    
+    def lerp(self, other, t):
+        p1 = PVector.lerp(self.p1, other.p1, t)
+        p2 = PVector.lerp(self.p2, other.p2, t)
+        return Line(p1, p2)
+    
+def line_instersect(line_a, line_b):     
+    """
+    code adapted from Bernardo Fontes 
+    https://github.com/berinhard/sketches/
+    """
+       
+    x1, y1 = line_a.p1.x, line_a.p1.y
+    x2, y2 = line_a.p2.x, line_a.p2.y
+    x3, y3 = line_b.p1.x, line_b.p1.y
+    x4, y4 = line_b.p2.x, line_b.p2.y
+        
+    try:
+        uA = ((x4-x3)*(y1-y3) - (y4-y3)*(x1-x3)) / ((y4-y3)*(x2-x1) - (x4-x3)*(y2-y1));
+        uB = ((x2-x1)*(y1-y3) - (y2-y1)*(x1-x3)) / ((y4-y3)*(x2-x1) - (x4-x3)*(y2-y1));
+    except ZeroDivisionError:
+        return
+        
+    if not(0 <= uA <= 1 and 0 <= uB <= 1):
+        return
+        
+    x = line_a.p1.x + uA * (line_a.p2.x - line_a.p1.x)
+    y = line_a.p1.y + uA * (line_a.p2.y - line_a.p1.y)
+        
+    return PVector(x, y)
+
+
+def edges(poly_points):
+    return pairwise(poly_points) + [(poly_points[-1], poly_points[0])]   
+
+def pairwise(iterable):
+    import itertools
+    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
+    a, b = itertools.tee(iterable)
+    next(b, None)
+    return zip(a, b) 
+
+def min_max(points):
+        points = iter(points)
+        try:
+            p = points.next()
+            min_x, min_y = max_x, max_y = p.x, p.y
+        except StopIteration:
+            raise ValueError, "min_max requires at least one point"
+        for p in points:
+            if p.x < min_x:
+                min_x = p.x
+            elif p.x > max_x:
+                max_x = p.x
+            if p.y < min_y:
+                min_y = p.y
+            elif p.y > max_y:
+                max_y = p.y
+        return (PVector(min_x, min_y),
+                PVector(max_x, max_y))
+        
+def par_hatch(points, divisions, *sides):
+        vectors = [PVector(p.x, p.y) for p in points]
+        lines = []
+        if not sides: sides = [0]
+        for s in sides:
+            a, b = vectors[-1 + s], vectors[+0 + s]
+            d, c = vectors[-2 + s], vectors[-3 + s]
+            for i in range(1, divisions):
+                s0 = PVector.lerp(a, b, i/float(divisions))
+                s1 = PVector.lerp(d, c, i/float(divisions))
+                lines.append(Line(s0, s1)) 
+        return lines

2020/sketch_2020_02_09a/sketch_2020_02_09a.pyde

@@ -0,0 +1,148 @@
+# Alexandre B A Villares - https://abav.lugaralgum.com/sketch-a-day
+
+SKETCH_NAME = "s06a"
+OUTPUT = ".pdf"
+GRID_SIZE = 30
+MARGIN = .1
+n = 1  # seed 0 -> n-1
+scaleFactor = 8
+
+from line_geometry import Line
+from line_geometry import par_hatch
+add_library('pdf')
+
+def setup():
+    global hires, s
+    size(600, 600)
+    smooth(8)
+    randomSeed(1)
+    init_grid(GRID_SIZE)
+    s = 1
+
+def draw():
+    # for s in range(1):
+    background(100)
+    hires = createGraphics(
+        width * scaleFactor,
+        height * scaleFactor,
+        PDF, "{}-highres.pdf".format(s))
+    # beginRecord(hires)
+    # hires.background(240)
+    # hires.strokeWeight(.33)
+    # hires.scale(scaleFactor)
+    for c in Cell.cells:
+        c.plot()
+
+    # hires.dispose()
+    # endRecord()
+    # hires.save("{}-highres".format(s) + OUTPUT)
+
+def keyPressed():
+    if key == ' ':
+        init_grid(GRID_SIZE)
+    if key == 's':
+        saveFrame("###.png")
+    if key == 'r':
+        for c in Cell.cells:
+            if random(10) < 1:
+                c.update()
+
+
+def mousePressed():
+    for c in Cell.cells:
+        if dist(c.px, c.py, mouseX, mouseY) < Cell.spacing:
+            c.update()
+
+def init_grid(grid_size):
+    Cell.border = width * MARGIN
+    Cell.spacing = (width - Cell.border * 2) / grid_size
+    Cell.cells = []
+    for x in range(0, grid_size, 2):
+        for y in range(0, grid_size, 2):
+            new_cell = Cell(x, y)
+            Cell.cells.append(new_cell)
+            # Cell.grid[x, y] = new_cell
+
+    # randomSeed(frameCount+2)
+    for x in range(-1, grid_size + 1, 2):
+        for y in range(-1, grid_size + 1, 2):
+            Node.grid[x, y] = Node(x, y)   # extrarir do dict
+            # Node.grid1[x, y] = Node(x, y)   # extrarir do dict
+    for c in Cell.cells:
+        c.set_vers()
+
+class Node():
+    grid = dict()
+
+    def __init__(self, x, y):
+        self.ix = x
+        self.iy = y
+        self.px = Cell.border + Cell.spacing + x * Cell.spacing
+        self.py = Cell.border + Cell.spacing + y * Cell.spacing
+        # if random(20) > 10:
+        #     mx, my = width / 2, height / 2
+        #     self.px -= (self.px - mx) * 0.15
+        #     self.py -= (self.py - my) * 0.15
+        self.x = self.px
+        self.y = self.py
+
+class Cell():
+    cells = []
+
+    def __init__(self, x, y):
+        self.ix = x
+        self.iy = y
+        self.px = Cell.border + Cell.spacing + x * Cell.spacing
+        self.py = Cell.border + Cell.spacing + y * Cell.spacing
+        self.vers = []
+        self.can_change = True
+
+    def plot(self, t=0):
+        if dist(self.px, self.py, mouseX, mouseY) < Cell.spacing:
+            fill(255, 100)
+        else:
+            fill(200, 100)
+        beginShape()
+        # stroke(255, 0, 0)
+        for p in self.vers:
+            vertex(p.x, p.y)
+        endShape(CLOSE)
+
+    def update(self):
+        Cell.cells.remove(self)
+        if self.can_change:
+            self.can_change = False
+            r = random(100)
+            y01 = (self.v0.y + self.v1.y) / 2
+            y23 = (self.v2.y + self.v3.y) / 2
+            x12 = (self.v1.x + self.v2.x) / 2
+            x30 = (self.v3.x + self.v0.x) / 2
+            if r < 33:
+                self.v0.y = y01  # -1-1
+                self.v1.y = y01  # -1+1
+                self.v2.y = y23  # +1-1
+                self.v3.y = y23  # +1+1
+            elif r < 66:
+                self.v0.x = x30  # -1-1
+                self.v1.x = x12  # -1+1
+                self.v2.x = x12  # +1-1
+                self.v3.x = x30  # +1+1
+            else:
+                self.v0.y, self.v0.x = y01, x30
+                self.v1.y, self.v1.x = y01, x12
+                self.v2.y, self.v2.x = y23, x12
+                self.v3.y, self.v3.x = y23, x30
+
+            # self.v3.x, self.v3.y = self.px, self.py
+            # mx, my = width / 2, height / 2
+            # for v in self.vers:
+            #     v.x -= (v.x - mx) * 0.15
+            #     v.y += (v.y - my) * 0.15
+            # self.v1 = self.v2 = self.v0
+
+    def set_vers(self):
+        self.v0 = Node.grid.get((self.ix - 1, self.iy - 1))
+        self.v1 = Node.grid.get((self.ix - 1, self.iy + 1))
+        self.v3 = Node.grid.get((self.ix + 1, self.iy - 1))
+        self.v2 = Node.grid.get((self.ix + 1, self.iy + 1))
+        self.vers = [self.v0, self.v1, self.v2, self.v3]