316

README.md

@@ -6,6 +6,13 @@ Hi! I'm [Alexandre Villares](https://abav.lugaralgum.com), let's see if I can ma
 
 If you enjoy this, be a [patreon](https://patreon.com/arteprog) or make a donation [here](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=HCGAKACDMVNV2) 
 
+---
+
+![s316](s316/s316.png)
+
+316: [code](https://github.com/villares/sketch-a-day/tree/master/s316) [[Py.Processing](https://villares.github.io/como-instalar-o-processing-modo-python/index-EN)]
+
+A 3D take on 314
 
 ---
 
@@ -13,12 +20,16 @@ If you enjoy this, be a [patreon](https://patreon.com/arteprog) or make a donati
 
 315: [GIF](s315/s315.gif) [code](https://github.com/villares/sketch-a-day/tree/master/s315) [[Py.Processing](https://villares.github.io/como-instalar-o-processing-modo-python/index-EN)]
 
+Horizontaly connected 314
+
 ---
 
 ![s314](s314/s314.png)
 
 314: [code](https://github.com/villares/sketch-a-day/tree/master/s314) [[Py.Processing](https://villares.github.io/como-instalar-o-processing-modo-python/index-EN)]
 
+Isolating elements from 313
+
 ---
 
 ![s313](s313/s313.png)

s316/gif_exporter.py

@@ -0,0 +1,42 @@
+"""
+Alexandre B A Villares http://abav.lugaralgum.com - GPL v3 
+
+A helper for the Processing gifAnimation library https://github.com/extrapixel/gif-animation/tree/3.0
+Download from https://github.com/villares/processing-play/blob/master/export_GIF/unzip_and_move_to_libraries_GifAnimation.zip
+This helper was inspired by an example by Art Simon https://github.com/APCSPrinciples/AnimatedGIF/
+
+# add at the start of your sketch:
+  add_library('gifAnimation')
+  from gif_exporter import gif_export
+# add at the end of draw():
+  gif_export(GifMaker)
+"""
+
+def gif_export(GifMaker,             # gets a reference to the library
+               filename="exported",  # .gif will be added
+               repeat=0,             # 0 makes it an "endless" animation
+               quality=255,          # quality range 0 - 255
+               delay=200,            # this is quick
+               frames=0,             # 0 will stop on keyPressed or frameCount >= 100000
+               finish=False):        # force stop
+    global gifExporter
+    try:
+        gifExporter
+    except NameError:
+        gifExporter = GifMaker(this, filename + ".gif")
+        gifExporter.setRepeat(repeat)
+        gifExporter.setQuality(quality)
+        gifExporter.setDelay(delay)
+        
+    gifExporter.addFrame()
+
+    if frames == 0:
+       if keyPressed or frameCount >= 100000:
+           finish = True
+    elif frameCount >= frames:
+        finish = True
+                
+    if finish:
+        gifExporter.finish()
+        print("gif saved")
+        exit()

s316/line_geometry.py

@@ -0,0 +1,147 @@
+
+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.p1.z,
+             self.p2.x, self.p2.y, self.p2.z)
+    
+    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, p.z) 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

s316/s316.pyde

@@ -0,0 +1,166 @@
+# Alexandre B A Villares - https://abav.lugaralgum.com/sketch-a-day
+SKETCH_NAME = "s316"  # 20181109
+OUTPUT = ".png"
+GRID_SIZE = 36
+
+from line_geometry import Line
+from line_geometry import par_hatch
+add_library('gifAnimation')
+from gif_exporter import gif_export
+
+# this rule was used to choose nodes that would move on 
+# earlier regular grid deformation sketches (now it's just a random selection)
+rule = lambda x, y: random(40) < 20
+
+def setup():
+    strokeCap(SQUARE)
+    size(700, 700, P3D)
+    init_grid(GRID_SIZE)
+    background(200)
+    ortho()
+    
+def draw():
+    f = frameCount/5.
+    #translate(-width/2, height/2)
+    background(200)
+
+    t = cos(f)/2
+    
+    for c in Cell.cells:
+        with pushMatrix():
+                translate(0, c.py)
+                rotateX(f)
+                translate(0, -c.py)
+                for i in range(32):
+                    c.plot(cos(i/5.)/2)
+
+    # if frameCount % 10 == 0:
+    #     print(t)
+    #     for c in Cell.cells:
+    #         c.plot(t)  
+            
+    if 0 < f < TWO_PI:
+        pass
+        gif_export(GifMaker, SKETCH_NAME)
+    else:
+        # for i in range(60):
+        #     gif_export(GifMaker, SKETCH_NAME)
+        noLoop()
+        pass
+
+def init_grid(grid_size):
+    Cell.border = 100.
+    Cell.spacing = (width - Cell.border *2) / grid_size
+    Cell.cells = []
+    randomSeed(1000)
+    for x in range(0, grid_size, 4):
+        for y in range(0, grid_size, 4):
+                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.grid0[x, y] = Node(x, y)   # extrarir do dict
+                Node.grid1[x, y] = Node(x, y)   # extrarir do dict
+
+
+    for c in Cell.cells:
+        c.update_vers()
+   
+class Node():
+    grid0 = dict()
+    grid1 = dict()
+
+    def __init__(self, x, y):
+        mx, my = width/2, height/2
+        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.pz = 0
+        if rule(x, y):
+           self.px += (self.px - mx) * 0.12 
+           self.py += (self.py - my) * 0.12
+           self.pz = (self.px - mx) * 0.12 - (self.py - my) * 0.12
+        self.x = self.px
+        self.y = self.py
+        self.py = 0
+        self.z = self.pz
+
+class Cell():
+    cells = []
+    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 
+        self.pz = 0
+        self.vers = []
+        self.num_hatches = int(random(3, 6))#int(random(5, 12))
+        self.type_hatches = random(10)      
+      
+    def plot(self, t):    
+        L0, V0 = self.lines, self.vers
+        L1, V1 = self.lines_f, self.vers_f
+
+        strokeWeight(1)
+        c = lerpColor(color(160, 0, 0),
+                      color(0, 0, 100), t)
+        stroke(c) 
+        for l0, l1 in zip(L0, L1):
+            l = l0.lerp(l1, t)
+            l.plot()
+        beginShape()
+        noFill()
+        #strokeWeight(1)
+        #stroke(100, 0, 100)
+        for p0, p1 in zip(V0, V1):
+            vertex(lerp(p0.x, p1.x, t), lerp(p0.y, p1.y, t), lerp(p0.z, p1.z, t) )
+        endShape(CLOSE)
+        
+    def update_vers(self):
+        self.v0 = Node.grid0.get((self.ix-1, self.iy-1))
+        self.v1 = Node.grid0.get((self.ix-1, self.iy+1))
+        self.v3 = Node.grid0.get((self.ix+1, self.iy-1))
+        self.v2 = Node.grid0.get((self.ix+1, self.iy+1))
+        self.vers = [self.v0, self.v1, self.v2, self.v3]
+        self.v0f = Node.grid1.get((self.ix-1, self.iy-1))
+        self.v1f = Node.grid1.get((self.ix-1, self.iy+1))
+        self.v3f = Node.grid1.get((self.ix+1, self.iy-1))
+        self.v2f = Node.grid1.get((self.ix+1, self.iy+1))
+        self.vers_f = [self.v0f, self.v1f, self.v2f, self.v3f]
+        self.hatch()
+        
+    def hatch(self):
+        self.lines = []
+        self.lines_f = []
+        n = self.num_hatches
+        r = self.type_hatches
+        if r > 2:                        
+            self.lines.extend(par_hatch(self.vers, n, 0))
+            self.lines_f.extend(par_hatch(self.vers_f, n, 0))
+        if r < 8:
+            self.lines.extend(par_hatch(self.vers, n, 1))
+            self.lines_f.extend(par_hatch(self.vers_f, n, 1))
+        
+def keyPressed():
+    if key == "n" or key == CODED:
+        init_grid(GRID_SIZE)
+        background(200)
+        loop()
+        #saveFrame("###.png")
+    if key == "s": saveFrame("###.png")
+
+# print text to add to the project's README.md             
+def settings():
+    println(
+"""
+![{0}]({0}/{0}{2})
+
+{1}: [code](https://github.com/villares/sketch-a-day/tree/master/{0}) [[Py.Processing](https://villares.github.io/como-instalar-o-processing-modo-python/index-EN)]
+""".format(SKETCH_NAME, SKETCH_NAME[1:], OUTPUT)
+    )