void PointLightInteractionHandler::setLightPosFromScreenCoords(const vec2& normalizedScreenCoord) {
vec2 deviceCoord(2.f * (normalizedScreenCoord - 0.5f));
// Flip vertical axis since mouse event y position starts at top of screen
deviceCoord.y *= -1.f;
// Use half distance between look from and look to positions as scene radius.
float sceneRadius = 0.5f * glm::length(camera_->getLookTo() - camera_->getLookFrom());
vec3 rayOrigin = camera_->getWorldPosFromNormalizedDeviceCoords(vec3(deviceCoord, 0.f));
vec3 rayDir = glm::normalize(
camera_->getWorldPosFromNormalizedDeviceCoords(vec3(deviceCoord, 1.f)) - rayOrigin);
float t0 = 0, t1 = std::numeric_limits<float>::max();
float lightRadius = glm::length(lightPosition_->get());
if (raySphereIntersection(vec3(0.f), sceneRadius, rayOrigin, rayDir, &t0, &t1)) {
lightPosition_->set(glm::normalize(rayOrigin + t1 * rayDir) * lightRadius);
} else {
// Project it to the rim of the sphere
t0 = 0;
t1 = std::numeric_limits<float>::max();
if (rayPlaneIntersection(camera_->getLookTo(),
glm::normalize(camera_->getLookTo() - camera_->getLookFrom()),
rayOrigin, rayDir, &t0, &t1)) {
// Project it to the edge of the sphere
lightPosition_->set(glm::normalize(rayOrigin + t1 * rayDir) * lightRadius);
}
}
// Ensure that up vector is same as camera afterwards
setLookUp(camera_->getLookUp());
}
void PointLightInteractionHandler::onCameraChanged() {
// This makes sure that the interaction with the light source is consistent with the direction
// of the camera
setLookUp(camera_->getLookUp());
}
void CameraProperty::setLook(vec3 lookFrom, vec3 lookTo, vec3 lookUp) {
NetworkLock lock(this);
setLookFrom(lookFrom);
setLookTo(lookTo);
setLookUp(lookUp);
}
