Create nodes according to the ground.

[ChanWoo.Sung]

When creating a node by calling a file from c++ code, is there a way to automatically create a node so that it touches the ground even if the position is specified as setWorldPosition and created higher than the ground?

[silent]

ChanWoo.Sung

Yes, you surely can do it. You need to do an intersection test (cast ray from top to the ground level) and get Z coordinate in the specific point. After that you can place your node in this point with an offset.

What are you currently using as ground (ObjectTerrainGlobal / ObjectLandscapeTerrain or regular mesh)?

Thanks!

[ChanWoo.Sung]

I'm using ObjectTerrainGlobal

Edited November 18, 2021 by ChanWoo.Sung

[cash-metall]

this is a simple example of how to set the height of an object to ground level.

bool drop_to_ground(const ObjectTerrainGlobalPtr &ground, const NodePtr &node, bool up_to_normal = true)
{
	// get original transform
	Mat4 node_world_transform = node->getWorldTransform();
	// world node position to local terrain position
	Vec3 position = ground->getIWorldTransform() * node_world_transform.getTranslate();
 
	ObjectIntersectionNormalPtr wi = ObjectIntersectionNormal::create();
	// get vertical intersection
	if (ground->getIntersection(position + UNIGINE_VEC3::UP  * 1000, position - UNIGINE_VEC3::UP  * 1000, wi, 0))
	{
		// terrain local position to world position
		position = ground->getWorldTransform() * wi->getPoint();
		// change z of original transform
		node_world_transform.m23 = position.z;
		
		if (up_to_normal)
		{
			vec3 normal;
			mul3(normal, ground->getWorldTransform(), wi->getNormal());
			node->setWorldTransform(setTo(node_world_transform.getTranslate(), node->getWorldTransform() * Vec3::FORWARD, normal, AXIS_Y));
		}
		else
		{
			node->setWorldTransform(node_world_transform);
		}
		return true;
	}
	return false;
}

I'm not sure if this works 100%. ask if there are any problems

[ChanWoo.Sung]

Quote

Thank you, I'll try it