def run(self): # Camera: origin = Vector(0,0,-255) direction = Vector(0,0,0) centerX = self.screen.width / 2 centerY = self.screen.height / 2 for y in range(self.screen.height): for x in range(self.screen.width): pixel_x = x - centerX pixel_y = y - centerY # Calculate direction direction.x = pixel_x direction.y = pixel_y direction.z = 255 direction.normalize() # Trace ray color = self.trace_ray(origin, direction, 3) # Draw resulting color color = (int(color[0]*255), int(color[1]*255), int(color[2]*255)) self.screen.putpixel(x, y, color)
def trace_ray(self, origin, direction, depth): color = (0,0,0) # Find closest object that intersects (t, hit_object) = self.intersect(origin, direction) if t: intersection = Vector( origin.x + direction.x*t, origin.y + direction.y*t, origin.z + direction.z*t ) intersection_normal = hit_object.computeNormal(intersection) # Ambient lighting: dff=hit_object.getDiffuse(intersection) color = (dff[0]*0.0, dff[1]*0.0, dff[2]*0.0) # Diffuse lighing for light in self.scene.lights: lightvec = Vector( light.x - intersection.x, light.y - intersection.y, light.z - intersection.z) lightvec.normalize() dot = lightvec.dot_product(intersection_normal) # Add color if vectors are pointing in the same direction if dot>0: color = ( color[0] + light.color[0]*dff[0] * dot, color[1] + light.color[1]*dff[1] * dot, color[2] + light.color[2]*dff[2] * dot ) # Reflection refl=0.2 # Fixed reflections for all materials. Pretty awesome! if depth>1 and refl>0: # Find direction for reflection dotp = direction.dot_product(intersection_normal) refVect = Vector( direction.x - 2 * dotp * intersection_normal.x, direction.y - 2 * dotp * intersection_normal.y, direction.z - 2 * dotp * intersection_normal.z ) # Trace reflection to get reflected color refc = self.trace_ray(intersection, refVect, depth-1); # If hit, we blend colors together invref=1-refl cc = ( invref*color[0] + refl*refc[0], invref*color[1] + refl*refc[1], invref*color[2] + refl*refc[2] ) color = cc return color
