def colour_at(self, obj_hit, hit_pos, normal, scene):
material = obj_hit.material
obj_colour = material.colour_at(hit_pos)
to_cam = scene.camera - hit_pos
specular_k = 50
colour = material.ambient * Colour.from_hex("#000000")
# Light calculations
for light in scene.lights:
to_light = Ray(hit_pos, light.position - hit_pos)
# Diffuse shading (Lambert)
colour += (
obj_colour
* material.diffuse
* max(normal.dot_product(to_light.direction), 0)
)
# Specular shading
half_vector = (to_light.direction + to_cam).normalise()
colour += (
light.colour
* material.specular
* max(normal.dot_product(half_vector), 0) ** specular_k
)
return colour
def main():
width = 3200
height = 2000
camera = Vector(0, 0, -0.5)
lights = [
Light(Point(0, -0.6, -6), Colour.from_hex("#FFFFFF")),
Light(Point(5, -0.9, 10), Colour.from_hex("#FFFFFF")),
Light(Point(-1, -0.9, 10), Colour.from_hex("#FFFFFF"))
]
objects = [
Sphere(Point(-0.53, 0, 1), 0.5, Material(Colour.from_hex("#FF0000"))),
Sphere(Point(0.53, 0, 1), 0.5, Material(Colour.from_hex("#F80000"))),
Sphere(Point(0, 1000000.5, 1), 1000000,
Material(Colour.from_hex("#FFFFFF")))
]
scene = Scene(camera, objects, lights, width, height)
engine = RenderEngine()
image = engine.render(scene)
with open("render.ppm", "w") as img_file:
image.write_ppm(img_file)
def __init__(self, colour=Colour.from_hex("#FFFFFF"), ambient=0.5, diffuse=1.0, specular=0.5):
self.colour = colour
self.ambient = ambient
self.diffuse = diffuse
self.specular = specular
def __init__(self, position, colour=Colour.from_hex("FFFFFF")):
self.position = position
self.colour = colour