Vector4 LightInfo::GetPointLightOnPoint(const Vector4& _cameraSpacePoint, const Vector4& _point, const Vector4& _normal, int _lightIndex, const Vector4& _diffuse, const Vector4& _specular) {
// Get the difference in position from the light and the point.
Vector4 diff = GetPointLights()[_lightIndex].GetPosition() - _point;
Vector4 lightDirection = diff;
// The distance
float distance = diff.Length();
// The direction
diff.Normalize();
// The attenuation
float attenuation = GetPointLights()[_lightIndex].GetAttenuation(distance);
// Diffuse lighting.
Vector4 pointColor = GetPointLights()[_lightIndex].GetIntensity()
* diff.Dot(_normal)
* attenuation
* _diffuse;
pointColor.Clamp();
// Specular
// We get the half angle between the camera and the direction to the camera.
Vector4 halfAngle = lightDirection + _cameraSpacePoint;
halfAngle.Normalize();
Vector4 specular = _specular * powf(halfAngle.Dot(_normal), 10) * attenuation;
specular.Clamp();
pointColor += specular;
return pointColor;
}
/* Get the light value for a point in space */
Vector4 LightInfo::GetDirectionalLightOnPoint(const Vector4& _cameraSpacePoint, const Vector4& _normal, int _lightIndex, const Vector4& _diffuse, const Vector4& _specular) {
Vector4 directionalColor = GetDirectionalLights()[_lightIndex].GetIntensity() * GetDirectionalLights()[_lightIndex].GetDirection().Dot(_normal) * _diffuse;
directionalColor.Clamp();
// Specular
Vector4 halfAngle = GetDirectionalLights()[_lightIndex].GetDirection() + _cameraSpacePoint;
halfAngle.Normalize();
Vector4 specular = _specular * powf(halfAngle.Dot(_normal), 100) * GetDirectionalLights()[_lightIndex].GetIntensity();
specular.Clamp();
directionalColor += specular;
return directionalColor;
}
