// If called for terrain has has not been previously allocated, a new terrain will be built
// based on the passed information. The 'id' should be either the terrain id or
// BSScene.CHILDTERRAIN_ID. If the latter, a new child terrain ID will be allocated and used.
// The latter feature is for creating child terrains for mega-regions.
// If there is an existing terrain body, a new
// terrain shape is created and added to the body.
// This call is most often used to update the heightMap and parameters of the terrain.
// (The above does suggest that some simplification/refactoring is in order.)
// Called during taint-time.
private void UpdateTerrain(uint id, float[] heightMap)
{
DetailLog("{0},BSTerrainManager.UpdateTerrain,call,id={1}",
BSScene.DetailLogZero, id);
if (m_terrain != null)
{
// There is already a terrain in this spot. Free the old and build the new.
DetailLog("{0},BSTErrainManager.UpdateTerrain:UpdateExisting,call,id={1}",
BSScene.DetailLogZero, id);
// Release any physical memory it may be using.
m_terrain.Dispose();
m_terrain = BuildPhysicalTerrain(id, heightMap);
m_terrainModified = true;
}
else
{
// We don't know about this terrain so either we are creating a new terrain or
// our mega-prim child is giving us a new terrain to add to the phys world
// if this is a child terrain, calculate a unique terrain id
uint newTerrainID = id;
if (newTerrainID >= BSScene.CHILDTERRAIN_ID)
newTerrainID = ++m_terrainCount;
DetailLog("{0},BSTerrainManager.UpdateTerrain:NewTerrain,taint,newID={1}",
BSScene.DetailLogZero, newTerrainID);
m_terrain = BuildPhysicalTerrain(id, heightMap);
m_terrainModified = true;
}
}
// Create the initial instance of terrain and the underlying ground plane.
// This is called from the initialization routine so we presume it is
// safe to call Bullet in real time. We hope no one is moving prims around yet.
public void CreateInitialGroundPlaneAndTerrain()
{
DetailLog("{0},BSTerrainManager.CreateInitialGroundPlaneAndTerrain,region={1}", BSScene.DetailLogZero, PhysicsScene.RegionName);
// The ground plane is here to catch things that are trying to drop to negative infinity
BulletShape groundPlaneShape = PhysicsScene.PE.CreateGroundPlaneShape(BSScene.GROUNDPLANE_ID, 1f, BSParam.TerrainCollisionMargin);
m_groundPlane = PhysicsScene.PE.CreateBodyWithDefaultMotionState(groundPlaneShape,
BSScene.GROUNDPLANE_ID, Vector3.Zero, Quaternion.Identity);
PhysicsScene.PE.AddObjectToWorld(PhysicsScene.World, m_groundPlane);
PhysicsScene.PE.UpdateSingleAabb(PhysicsScene.World, m_groundPlane);
// Ground plane does not move
PhysicsScene.PE.ForceActivationState(m_groundPlane, ActivationState.DISABLE_SIMULATION);
// Everything collides with the ground plane.
m_groundPlane.collisionType = CollisionType.Groundplane;
m_groundPlane.ApplyCollisionMask(PhysicsScene);
m_terrain = new BSTerrainHeightmap(PhysicsScene, Vector3.Zero, BSScene.TERRAIN_ID, m_worldMax);
}
