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switch(Lightmode){
		case 0:
			{
				vec3 i = normalize(light.position);
				vec3 j = normalize(cameraPosition - vertex_pos);
				vec3 k = normalize(i + j);
				vec3 l = normalize(vertex_normal);

				vec3 ambient = light.ambient * material.Ka;
				vec3 diffuse = max(dot(i, l), 0.0) * light.diffuse * material.Kd;
				vec3 specular = pow(max(dot(k, l), 0.0), shininess) * light.specular * material.Ks;
				vertex_color = ambient + diffuse + specular;
				break;
			}
		case 1:
			{
				vec3 i = normalize(light.position - vertex_pos);
				vec3 j = normalize(cameraPosition - vertex_pos);
				vec3 k = normalize(i + j);
				vec3 l = normalize(vertex_normal);

				vec3 ambient = light.ambient * material.Ka;
				vec3 diffuse = max(dot(i, l), 0.0) * light.diffuse * material.Kd;
				vec3 specular = pow(max(dot(k, l), 0.0), shininess) * light.specular * material.Ks;

				float dist = length(light.position - vertex_pos);
				float attenuation = light.Constant + light.Linear * dist + light.Quadratic * dist * dist;
				float f = min(1. / attenuation, 1.);
				vertex_color = ambient + f * (diffuse + specular);
				break;
			}
		case 2:
			{
				vec3 i = normalize(light.position - vertex_pos);
				vec3 j = normalize(cameraPosition - vertex_pos);
				vec3 k = normalize(i + j);
				vec3 l = normalize(vertex_normal);

				vec3 ambient = light.ambient * material.Ka;
				vec3 diffuse = max(dot(i, l), 0.0) * light.diffuse * material.Kd;
				vec3 specular = pow(max(dot(k, l), 0.0), shininess) * light.specular * material.Ks;

				float dist = length(light.position - vertex_pos);
				float attenuation = light.Constant + light.Linear * dist + light.Quadratic * dist * dist;
				float f = min(1. / attenuation, 1.);

				vec3 x = normalize(vertex_pos - light.position);
				vec3 y = normalize(spotlight.direction);
				float xy = dot(x, y);
				float spoteffect = 0;
				if(xy > cos(spotlight.cutoff * acos(-1) / 180.0))
					spoteffect = pow(max(xy, 0.0), spotlight.exponent);
				vertex_color = ambient + spoteffect * f * (diffuse + specular);
				break;
			}
		default:
			break;
	}