def test_determine_diffuse_contribution(self):
sphere = data.Sphere(data.Point(0, 0, 0), 1, data.Color(0.5, 0.7, 0.8), data.Finish(0.5, 0.5, 0.5, 0.05))
light = data.Light(data.Point(0, 0, 100), data.Color(1.5, 1.2, 1.3))
inter_point = data.Point(0, 0, 1)
inter_list = [
(
data.Sphere(data.Point(0, 0, 102), 1, data.Color(0.5, 0.7, 0.8), data.Finish(0.5, 0.5, 0.5, 0.05)),
data.Point(0, 0, 101),
)
]
normal = collisions.sphere_normal_at_point(sphere, inter_point)
off_pt = cast.find_pt_off_sphere(inter_point, normal)
dir_vect = vector_math.normalize_vector(vector_math.vector_from_to(off_pt, light.pt))
ray = data.Ray(off_pt, dir_vect)
sphere_list = []
l_dir = vector_math.normalize_vector(vector_math.vector_from_to(off_pt, light.pt))
l_dot_n = vector_math.dot_vector(normal, l_dir)
result = cast.determine_diffuse_contribution(sphere, off_pt, light, normal, sphere_list, l_dir, l_dot_n)
self.assertEqual(
result[0], cast.get_diffuse_contribution(sphere, light, ray, inter_list, normal, dir_vect, off_pt)[0]
)
self.assertEqual(
result[1], cast.get_diffuse_contribution(sphere, light, ray, inter_list, normal, dir_vect, off_pt)[1]
)
self.assertEqual(
result[2], cast.get_diffuse_contribution(sphere, light, ray, inter_list, normal, dir_vect, off_pt)[2]
)
def test_vectorToFrom_1(self): p1 = data.Point(1,2,3) p2 = data.Point(0,0,0) v1 = vector_math.vector_from_to(p1, p2) v2 = vector_math.vector_from_to(p2, p1) equals1 = data.Vector(-1, -2, -3) equals2 = vector_math.scale_vector(v1, -1) self.assertEqual(v1 == equals1, True) self.assertEqual(v2 == equals2, True) pass
def cast_ray(ray, sphere_list, color, light):
"""Find the rendered color at the nearest intersection point along ray"""
nearest = closest_intersect(ray, sphere_list)
if not nearest:
# No intersection, return white
return Color(1.0, 1.0, 1.0)
point, sphere = nearest
# Compute initial ambient colors
r = sphere.color.r * sphere.finish.ambient * color.r
g = sphere.color.g * sphere.finish.ambient * color.g
b = sphere.color.b * sphere.finish.ambient * color.b
# Calculate diffuse value
normal = sphere_normal_at_point(sphere, point)
to_light = normalize_vector(vector_from_to(point, light.pt))
l_dot = dot_vector(normal, to_light)
diffuse = sphere.finish.diffuse * l_dot
if diffuse < 0:
diffuse = 0
else:
# Check for shadows
new_point = translate_point(point, scale_vector(normal, 0.01))
light_ray = Ray(new_point, to_light)
shadow_intersect = closest_intersect(light_ray, sphere_list)
if (shadow_intersect and
length_vector_sq(vector_from_to(new_point, shadow_intersect[0]))
< length_vector_sq(vector_from_to(new_point, light.pt))):
diffuse = 0
# Add diffuse to existing colors
r += sphere.color.r * diffuse * light.color.r
g += sphere.color.g * diffuse * light.color.g
b += sphere.color.b * diffuse * light.color.b
# Compute specular intensity
if diffuse > 0:
reflection = difference_vector(to_light, scale_vector(normal, 2 * l_dot))
intensity = dot_vector(reflection, normalize_vector(ray.dir))
power = 1. / sphere.finish.roughness
if intensity > 0:
r += light.color.r * sphere.finish.specular * intensity ** power
g += light.color.g * sphere.finish.specular * intensity ** power
b += light.color.b * sphere.finish.specular * intensity ** power
# Max out colors at 1.0
if r > 1:
r = 1
if g > 1:
g = 1
if b > 1:
b = 1
return Color(r, g, b)
def find_closest(inter,ray): close = vector_math.length_vector(vector_math.vector_from_to(ray.pt,inter[0][1])) sphere = inter[0][0] point = inter[0][1] for (s,p) in inter: distance = vector_math.length_vector(vector_math.vector_from_to(ray.pt,p)) if close > distance: close = distance sphere = s point = p return sphere, point
def cast_ray(ray, sphere_list, amb, light, eye_point):
result_color = data.Color(1.0, 1.0, 1.0)
# test for closest sphere to the eye
collision_tuple = find_closest_collision(ray, sphere_list)
if collision_tuple:
# some useful variables
sphere_hit = collision_tuple[0]
sphere_hit_point = collision_tuple[1]
# basic color before manipulation
result_r = sphere_hit.color.r * sphere_hit.finish.amb * amb.r
result_g = sphere_hit.color.g * sphere_hit.finish.amb * amb.g
result_b = sphere_hit.color.b * sphere_hit.finish.amb * amb.b
# computing light intensity
sphere_vector = vector_math.vector_from_to(sphere_hit.center, sphere_hit_point)
sphere_normal = vector_math.normalize_vector(sphere_vector)
scaled_normal = vector_math.scale_vector(sphere_normal, 0.01)
hit_point = vector_math.translate_point(sphere_hit_point, scaled_normal)
light_vector = vector_math.vector_from_to(hit_point, light.pt)
light_normal = vector_math.normalize_vector(light_vector)
light_scale = vector_math.dot_vector(sphere_normal, light_normal)
if light_scale > 0:
sphere_normal_ray = data.Ray(hit_point, light_normal)
possible_obstruction = find_closest_collision(sphere_normal_ray, sphere_list)
if possible_obstruction == None or distance(hit_point, possible_obstruction[1]) > distance(
hit_point, light.pt
):
result_r += sphere_hit.color.r * light_scale * light.color.r * sphere_hit.finish.diff
result_g += sphere_hit.color.g * light_scale * light.color.g * sphere_hit.finish.diff
result_b += sphere_hit.color.b * light_scale * light.color.b * sphere_hit.finish.diff
# computing specular intensity
tmp_vector = vector_math.scale_vector(sphere_normal, 2 * light_scale)
reflection_vector = vector_math.difference_vector(light_normal, tmp_vector)
eye_vector = vector_math.vector_from_to(eye_point, hit_point)
eye_normal = vector_math.normalize_vector(eye_vector)
spec_scale = vector_math.dot_vector(reflection_vector, eye_normal)
if spec_scale > 0:
result_r += light.color.r * sphere_hit.finish.spec * spec_scale ** (1 / float(sphere_hit.finish.rough))
result_g += light.color.g * sphere_hit.finish.spec * spec_scale ** (1 / float(sphere_hit.finish.rough))
result_b += light.color.b * sphere_hit.finish.spec * spec_scale ** (1 / float(sphere_hit.finish.rough))
result_color = data.Color(result_r, result_g, result_b)
return result_color
def closest_intersect(ray, sphere_list):
"""Find the nearest intersection point and sphere"""
intersections = find_intersection_points(ray, sphere_list)
if len(intersections) < 1:
# We don't intersect anything
return None
# Find the nearest intersection point and its sphere
nearest = intersections[0]
nearest_dist_sq = length_vector_sq(vector_from_to(ray.pt, nearest[0]))
for tup in intersections[1:]:
dist_sq = length_vector_sq(vector_from_to(ray.pt, tup[0]))
if dist_sq < nearest_dist_sq:
nearest = tup
nearest_dist_sq = dist_sq
return nearest
def test_cast_ray_1(self):
ray = data.Ray(data.Point(0, 10, 6), data.Vector(0, 0, -2))
sphere_list = [
data.Sphere(data.Point(0, 10, -2), 3, data.Color(0, 0.5, 1.0), data.Finish(0.5, 0.4, 0.5, 0.05)),
data.Sphere(data.Point(0, 10, -20), 0.5, data.Color(0, 0.3, 0.2), data.Finish(0.5, 0.4, 0.5, 0.05)),
]
ambient_color = data.Color(0.25, 0.5, 0.75)
light = data.Light(data.Point(-100.0, 100.0, -100.0), data.Color(1.5, 1.5, 1.5))
eye_position = data.Point(0, 0, -14)
cr = cast.cast_ray(ray, sphere_list, ambient_color, light, eye_position)
inter_point = collisions.sphere_intersection_point(ray, sphere_list[0])
normal = collisions.sphere_normal_at_point(sphere_list[0], inter_point)
off_pt = cast.find_pt_off_sphere(inter_point, normal)
l_dir = vector_math.normalize_vector(vector_math.vector_from_to(off_pt, light.pt))
l_dot_n = vector_math.dot_vector(normal, l_dir)
diffuse_list = cast.determine_diffuse_contribution(
sphere_list[0], off_pt, light, normal, sphere_list, l_dir, l_dot_n
)
spec_list = cast.determine_specular_contribution(
l_dir, l_dot_n, normal, eye_position, off_pt, light.color, sphere_list[0].finish
)
self.assertEqual(
cr,
data.Color(
0 + diffuse_list[0] + spec_list[0],
0.125 + diffuse_list[1] + spec_list[1],
0.375 + diffuse_list[2] + spec_list[2],
),
)
def determine_specular_contribution(l_dir,l_dot_n,normal,eye_position,
off_pt,light,sphere_finish,ray,
inter_list):
reflection_vect = vector_math.difference_vector(l_dir,
vector_math.scale_vector(normal,
2 * l_dot_n))
v_dir = vector_math.normalize_vector(
vector_math.vector_from_to(eye_position,off_pt))
spec_intensity = vector_math.dot_vector(reflection_vect,v_dir)
def compute_spec(color_comp):
return (color_comp * sphere_finish.specular *
(spec_intensity ** (1 / sphere_finish.roughness)))
if spec_intensity > 0:
r_comp = compute_spec(light.color.r)
g_comp = compute_spec(light.color.g)
b_comp = compute_spec(light.color.b)
if inter_list == []:
return [r_comp,g_comp,b_comp]
else:
dist_pt_to_light = distance(off_pt,light.pt)
nearest_point = find_nearest(inter_list,ray)
if distance(off_pt,nearest_point) < dist_pt_to_light:
return [0,0,0]
else:
return [r_comp,g_comp,b_comp]
else:
return [0,0,0]
def cast_all_rays(min_x, max_x, min_y, max_y, width, height, eye_point, sphere_list, ambient_color, light):
f = open("image.ppm", 'w')
f.write("P3\n")
f.write("%d %d\n" % (width, height))
f.write("255\n")
w = max_x - min_x
h = max_y - min_y
scale_x = w / width
scale_y = h / height
total = width * height
percent = 0
for i in range(height):
print int(percent)
for j in range(width):
position = width * i + j
percent = float(position) / total * 100
x = j * scale_x + min_x
y = max_y - i * scale_y
dir = vector_math.vector_from_to(eye_point, data.Point(x,y,0))
ray = data.Ray(eye_point, dir)
b = cast_ray(ray, sphere_list, ambient_color, light, eye_point)
print_color(f,b)
def test_vectorToFrom_2(self): p1 = data.Point(4,4,4) p2 = data.Point(1,2,3) v1 = vector_math.vector_from_to(p1, p2) equals = data.Vector(-3, -2, -1) self.assertEqual(v1 == equals, True) pass
def test_get_diffuse_contribution(self):
sphere = data.Sphere(data.Point(0, 0, 0), 1, data.Color(0.5, 0.7, 0.8), data.Finish(0.5, 0.5, 0.5, 0.05))
light = data.Light(data.Point(0, 0, 100), data.Color(1.5, 1.2, 1.3))
inter_point = data.Point(0, 0, 1)
normal = collisions.sphere_normal_at_point(sphere, inter_point)
inter_list = []
off_pt = cast.find_pt_off_sphere(inter_point, normal)
dir_vect = vector_math.normalize_vector(vector_math.vector_from_to(off_pt, light.pt))
ray = data.Ray(off_pt, dir_vect)
result = cast.get_diffuse_contribution(sphere, light, ray, inter_list, normal, dir_vect, off_pt)
self.assertEqual(result[0], (vector_math.dot_vector(normal, dir_vect) * 1.5 * 0.5 * 0.5))
self.assertEqual(result[1], (vector_math.dot_vector(normal, dir_vect) * 1.2 * 0.7 * 0.5))
self.assertEqual(result[2], (vector_math.dot_vector(normal, dir_vect) * 1.3 * 0.8 * 0.5))
def get_diffuse_color(tu, light, s_list):
pE = get_pe(tu)
N = collisions.sphere_normal_at_point(tu[0], tu[1])
lDir = vector_math.vector_from_to(pE, light.pt)
lDir = vector_math.normalize_vector(lDir)
lDirection = vector_math.dot_vector(N, lDir)
sI = get_specular_intensity(lDir, lDirection, N, pE, light, tu[0])
ray = data.Ray(pE, lDir)
if lDirection <= 0 or collides_with_spheres(ray, s_list, pE, light):
return data.Color(0,0,0)
dif = get_diffuse(lDirection, light, tu[0], tu[0].finish.diffuse)
finalColor = data.Color(sI.r + dif.r, sI.g + dif.g, sI.b + dif.b)
return finalColor
def comp(sphere_list,inter,light,sphere,int,eye_point): n = collisions.sphere_normal_at_point(sphere,int) scaled_normal = vector_math.scale_vector(n,.01) Pe = vector_math.translate_point(inter[0][1],scaled_normal) vr_light = vector_math.vector_from_to(Pe,light.pt) L_dir = vector_math.normalize_vector(vr_light) dot_product = vector_math.dot_vector(n,L_dir) reflection_vr = vector_math.difference_vector(L_dir,vector_math.scale_vector(n,(2 * dot_product))) V_dir = vector_math.normalize_vector(vector_math.vector_from_to(eye_point,Pe)) intensity = vector_math.dot_vector(reflection_vr,V_dir) ray = data.Ray(Pe,L_dir) inter2 = collisions.find_intersection_points(sphere_list,ray) if dot_product>0 and inter2 == []: diff_r = sphere.color.r*sphere.finish.diffuse*dot_product*light.color.r diff_g = sphere.color.g*sphere.finish.diffuse*dot_product*light.color.g diff_b = sphere.color.b*sphere.finish.diffuse*dot_product*light.color.b spec_r = light.color.r*sphere.finish.specular*math.pow(intensity,(1/sphere.finish.roughness)) spec_g = light.color.g*sphere.finish.specular*math.pow(intensity,(1/sphere.finish.roughness)) spec_b = light.color.b*sphere.finish.specular*math.pow(intensity,(1/sphere.finish.roughness)) return data.Color(diff_r,diff_g,diff_b),data.Color(spec_r,spec_g,spec_b) else : return data.Color(0,0,0), data.Color(0,0,0)
def get_specular_intensity(lDir, lDirection, N, pE, light, sphere):
reflection_vector = vector_math.difference_vector(lDir, vector_math.scale_vector(N, lDirection * 2))
vDir = vector_math.vector_from_to(data.Point(0.0,0.0,-14.0), pE)
vDir = vector_math.normalize_vector(vDir)
intensity = vector_math.dot_vector(reflection_vector, vDir)
if intensity > 0:
r = light.color.r * sphere.finish.specular * intensity**(1 / sphere.finish.roughness)
g = light.color.g * sphere.finish.specular * intensity**(1 / sphere.finish.roughness)
b = light.color.b * sphere.finish.specular * intensity**(1 / sphere.finish.roughness)
color = data.Color(r,g,b)
else:
color = data.Color(0,0,0)
return color
def cast_all_rays(view, eye_point, sphere_list, amb, light, file):
j = view.max_y
while j > view.min_y:
i = view.min_x
while i < view.max_x:
screen_point = data.Point(i, j, 0)
dir_to_pixel = vector_math.vector_from_to(eye_point, screen_point)
ray = data.Ray(eye_point, dir_to_pixel)
color = cast_ray(ray, sphere_list, amb, light, eye_point)
printed_r = str(color_convert(color.r))
printed_g = str(color_convert(color.g))
printed_b = str(color_convert(color.b))
file.write("{0} {1} {2}\n".format(printed_r, printed_g, printed_b))
i += find_delta(view.min_x, view.max_x, view.width)
j -= find_delta(view.min_y, view.max_y, view.height)
def cast_all_rays(min_x, max_x, min_y, max_y, width, height, eye_point, sphere_list,amb,light):
image = open('image.ppm','w')
print >> image, 'P3'
print >> image, width, height
print >> image, 255
distx=(max_x-min_x)/float(width)
disty=(max_y-min_y)/float(height)
for y in range(height):
for x in range(width):
pix_x = min_x + distx*x
pix_y = max_y - disty*y
vr = vector_math.vector_from_to(eye_point,data.Point(pix_x,pix_y,0.0))
ray = data.Ray(eye_point,vr)
color = cast_ray(ray,sphere_list,amb,light,eye_point)
print >> image, int(min(color.r*255,255)),int(min(color.g*255,255)),int(min(color.b*255,255))
def cast_ray(ray,sphere_list,ambient_color,light,eye_position):
inter_list = collisions.find_intersection_points(sphere_list,
ray)
if inter_list != []:
mindex = 0
for i in range(1,len(inter_list)):
if (distance(ray.pt,inter_list[i][1]) <
distance(ray.pt,inter_list[mindex][1])):
mindex = i
result_sphere = inter_list[mindex][0]
inter_point = inter_list[mindex][1]
sphere_color = result_sphere.color
sphere_finish = result_sphere.finish
sphere_normal = collisions.sphere_normal_at_point(result_sphere,
inter_point)
pt_off_sphere = find_pt_off_sphere(inter_point,sphere_normal)
l_dir = vector_math.normalize_vector(
vector_math.vector_from_to(pt_off_sphere,
light.pt))
l_dot_n = vector_math.dot_vector(sphere_normal,l_dir)
ray_off_to_l = data.Ray(pt_off_sphere,l_dir)
inter_list = collisions.find_intersection_points(sphere_list,ray_off_to_l)
diffuse_list = determine_diffuse_contribution(result_sphere,
pt_off_sphere,
light,sphere_normal,
sphere_list,l_dir,
l_dot_n,ray_off_to_l,
inter_list)
spec_intensity = determine_specular_contribution(l_dir,l_dot_n,
sphere_normal,
eye_position,
pt_off_sphere,
light,
result_sphere.finish,
ray_off_to_l,inter_list)
result_r = ((sphere_color.r * sphere_finish.ambient *
ambient_color.r) + diffuse_list[0] + spec_intensity[0])
result_g = ((sphere_color.g * sphere_finish.ambient *
ambient_color.g) + diffuse_list[1] + spec_intensity[1])
result_b = ((sphere_color.b * sphere_finish.ambient *
ambient_color.b) + diffuse_list[2] + spec_intensity[2])
return data.Color(result_r,result_g,result_b)
else:
return ambient_color
def cast_all_rays(min_x, max_x, min_y, max_y, width, height, eye_point,
sphere_list, color, light, file):
"""
Loop through all potetial points in xy-plane, calculating the ray from
eye_point to that point. For each point, determine the projected color by
applying cast_ray on the sphere list
Outputs one line per pixel with decimal r, g, b values separated by a space
"""
for y in range(height):
for x in range(width):
pt = Point(min_x + (max_x - min_x) * x / float(width),
max_y - (max_y - min_y) * y / float(height), 0.0)
ray = Ray(eye_point, vector_from_to(eye_point, pt))
c = cast_ray(ray, sphere_list, color, light)
file.write(str(int(c.r * 255)) + ' ')
file.write(str(int(c.g * 255)) + ' ')
file.write(str(int(c.b * 255)) + ' ')
def distance(p1, p2):
vector = vector_math.vector_from_to(p1, p2)
return vector_math.length_vector(vector)
def test_vector_from_to_1(self):
p1 = data.Point(0.0, 0.0, 0.0)
p2 = data.Point(1.0, 2.0, 3.0)
v = vector_math.vector_from_to(p1, p2)
self.assertEqual(v, data.Vector(1.0, 2.0, 3.0))
def test_vector_from_to_1(self):
from_point1 = data.Point(4, 8, 7)
to_point1 = data.Point(5, 9, 6)
travel = data.Point(1, 1, -1)
self.assertEqual(vector_math.vector_from_to(from_point1, to_point1), travel)
def test_vector_from_to_2(self):
from_point2 = data.Point(-8, 5, -6)
to_point2 = data.Point(12, 15, -24)
travel = data.Point(20, 10, -18)
self.assertEqual(vector_math.vector_from_to(from_point2, to_point2), travel)
def test_vector_from_to_2(self):
pt_1 = data.Point(2, 2, 2)
pt_2 = data.Point(6, 6, 6)
n_v = data.Vector(4, 4, 4)
self.assertAlmostEqual(vector_math.vector_from_to(pt_1, pt_2), n_v)
def test_vector_from_to_again(self):
vft = vector_math.vector_from_to(data.Point(0, 0, 1), data.Point(-3.3, 8, 9.9))
self.assertEqual(vft, data.Vector(-3.3, 8, 8.9))
def test_vector_from_to(self):
vft = vector_math.vector_from_to(data.Point(3, -6, 2.9), data.Point(7, -7, 0.3))
self.assertEqual(vft, data.Vector(4, -1, -2.6))
def sphere_normal_at_point(sphere,point):
return vector_math.normalize_vector(vector_math.vector_from_to(sphere.center,
point))
def test_vector_from_to(self):
pt_1 = data.Point(1, 1, 1)
pt_2 = data.Point(5, 5, 5)
n_v = data.Vector(4, 4, 4)
self.assertAlmostEqual(vector_math.vector_from_to(pt_1, pt_2), n_v)
