private TerrainPatch( TerrainPatch parent, TerrainPatchVertices vertices, Point3 origin, Vector3 uAxis, Vector3 vAxis, float patchError, Point2 uv, float uvRes )
{
m_Parent = parent;
m_Vertices = vertices;
m_LocalOrigin = origin;
m_LocalUAxis = uAxis;
m_LocalVAxis = vAxis;
m_Radius = ( uAxis + vAxis ).Length;
m_PatchError = patchError;
m_IncreaseDetailDistance = float.MaxValue;
m_UvRes = uvRes;
m_Uv = uv;
}
/// <summary>
/// Adds patches that cover the side of a cube
/// </summary>
/// <param name="res">Patch resolution (res*res patches cover the cube side)</param>
/// <param name="topLeft">The top left corner of the cube side</param>
/// <param name="topRight">The top right corner of the cube side</param>
/// <param name="bottomLeft">The bottom left corner of the cube side</param>
/// <param name="uvRes">The UV resolution of the cube patch</param>
private void AddCubeSidePatches( int res, Point3 topLeft, Point3 topRight, Point3 bottomLeft, float uvRes )
{
Vector3 xAxis = ( topRight - topLeft );
Vector3 yAxis = ( bottomLeft - topLeft );
Vector3 xInc = xAxis / res;
Vector3 yInc = yAxis / res;
Point3 rowStart = topLeft;
for ( int row = 0; row < res; ++row )
{
Point3 curPos = rowStart;
for ( int col = 0; col < res; ++col )
{
TerrainPatch newPatch = new TerrainPatch( Vertices, curPos, xInc, yInc, new Point2( 0, 0 ), uvRes );
RootPatches.Add( newPatch );
curPos += xInc;
}
rowStart += yInc;
}
}
/// <summary>
/// Increases the detail of this paqtch
/// </summary>
private void IncreaseDetail( ITerrainPatchGenerator generator, IProjectionCamera camera )
{
if ( m_CachedChildren != null )
{
// Child nodes have already been created - they just need new vertex buffers
m_PendingChildren = m_CachedChildren;
m_CachedChildren = null;
}
else
{
Vector3 uOffset = m_LocalUAxis * 0.5f;
Vector3 vOffset = m_LocalVAxis * 0.5f;
float error = m_PatchError / 2;
// float error = float.MaxValue;// Use this value to force a recalculation of the patch error
float uvRes = m_UvRes / 2;
Point2 tlUv = m_Uv;
Point2 trUv = m_Uv + new Vector2( uvRes, 0 );
Point2 brUv = m_Uv + new Vector2( uvRes, uvRes );
Point2 blUv = m_Uv + new Vector2( 0, uvRes );
TerrainPatch tl = new TerrainPatch( this, m_Vertices, m_LocalOrigin, uOffset, vOffset, error, tlUv,uvRes );
TerrainPatch tr = new TerrainPatch( this, m_Vertices, m_LocalOrigin + uOffset, uOffset, vOffset, error, trUv, uvRes );
TerrainPatch bl = new TerrainPatch( this, m_Vertices, m_LocalOrigin + vOffset, uOffset, vOffset, error, blUv, uvRes );
TerrainPatch br = new TerrainPatch( this, m_Vertices, m_LocalOrigin + uOffset + vOffset, uOffset, vOffset, error, brUv, uvRes );
m_PendingChildren = new TerrainPatch[] { tl, tr, bl, br };
}
foreach ( TerrainPatch patch in m_PendingChildren )
{
patch.Build( generator, camera );
}
}