Direct3DIndexBuffer8.Lock

Locks a range of index data and obtains access to the index buffer memory.

object.Lock( _ 
    OffsetToLock As Long, _ 
    SizeToLock As Long, _ 
    Data As Long, _ 
    Flags As Long)

Parts

object

Object expression that resolves to a Direct3DIndexBuffer8 object.

OffsetToLock

Offset into the index data to lock, in bytes. Lock the entire index buffer by specifying 0 for both parameters, SizeToLock and OffsetToLock.

SizeToLock

Size of the index data to lock, in bytes. Lock the entire index buffer by specifying 0 for both parameters, SizeToLock and OffsetToLock.

Data

First element of an array of Long values, filled with the returned index data

Flags

Combination of zero or more valid locking flags defined by the CONST_D3DLOCKFLAGS enumeration, describing how the index buffer memory should be locked.

Error Codes

If the method fails, an error is raised and Err.Number can be set to D3DERR_INVALIDCALL.

For information on trapping errors, see the Microsoft® Visual Basic® Error Handling topic.

Remarks

To lock, read, and unlock index data with a single function call, use D3DIndexBuffer8GetData.

To lock, fill, and unlock index data with a single function call, use D3DIndexBuffer8SetData.

When working with index buffers, you can make multiple lock calls; however, you must ensure that the number of lock calls match the number of unlock calls. DrawPrimitive calls will not succeed with any outstanding lock count on any currently set index buffer.

See Using Dynamic Vertex and Index Buffers for information on using D3DLOCK_DISCARD or D3DLOCK_NOOVERWRITE for the Flags parameter of the Lock method.

See Also

Direct3DIndexBuffer8.Unlock, D3DIndexBuffer8GetData, D3DIndexBuffer8SetData