IGpuBuffer

Description

interface Tinman.Terrain.Rendering.IGpuBuffer

Derived from: ICapacity
INativeHandle
IResource
Extended by: GpuBufferBase ^abstract
IIndexBuffer
IVertexBuffer

A GPU buffer, storing elements of fixed size, typically stored in high-performance memory.

Buffer data is written in binary form.

A buffer may have an element size of zero (see ElementSize). In this case, the buffer has an undefined structure and is used as a raw byte buffer.

Public / Methods

BufferMap

public method BufferMap → (2)

flag ⁱⁿ : GpuUpdateFlag: The update flag to apply.
countMax ^opt : int32 = -1: [-1..ICapacity.Capacity]
Maximum value that will be passed to the count parameter of BufferPrepare. If -1, ICapacity.Capacity will be used.
returns → ByteBuffer: The byte buffer to use for writing updated values: the position is 0 (which points to the start of the first element resp. byte in this GPU buffer), the capacity encompasses at least countMax ^opt elements resp. bytes and the limit is 0. Before any data may be written, BufferPrepare must be called in order to prepare the returned buffer.

Maps a region of this buffer for writing.

This is the preferred way of updating a GPU buffer with ResourceAccessPattern.Mappable access.

This method can also be used on GPU buffers with ResourceAccessPattern.Dynamic access. In this case, the implementing class will transparently map the API calls to BufferUpdate.

See also: IGpuBuffer.BufferUnmap

BufferPrepare

public method BufferPrepare → (2)

first ^opt : int32 = 0: [0..ICapacity.Capacity]
Index of the first element resp. byte in this buffer to update.
count ^opt : int32 = -1: [-1..ICapacity.Capacity-first]
Total number of elements resp. bytes to update in this buffer. If -1, the value min(countMax,Capacity-first) will be used, where countMax is the maximum count that has been passed to BufferMap.

Prepares the buffer that has been returned by BufferMap for writing to a range of elements resp. bytes.

This method may only be called between calls to BufferMap and BufferUnmap.

See also: IGpuBuffer.ElementSize

BufferUnmap

public method BufferUnmap → ()

Unmaps a this buffer.

Calling BufferUnmap on a buffer that cannot be locked (i.e. GpuBufferFlags.Update is not present) or without a prior call to BufferMap does not have any effect, the method just returns silently.

See also: IGpuBuffer.BufferMap

BufferUpdate

public method BufferUpdate → (5)

first ⁱⁿ : int32: [>=0]
Index of the first element resp. byte in this buffer to update.
values ⁱⁿ : ByteBuffer: [not-null]
A buffer holding the updated elements resp. bytes. The buffer position and limit will neither be modified nor taken into account by this method.
offset ⁱⁿ : int32: [>=0]
Offset into values ⁱⁿ to first element resp. byte to read.
count ⁱⁿ : int32: [>=0]
Total number of elements resp. bytes to update in this buffer.
flag ^opt : GpuUpdateFlag = GpuUpdateFlag.Discard: The update flag to apply.

Updates a range of elements in the buffer.

To prevent an overflow in the GPU buffer, the given data will be truncated by reducing the count ⁱⁿ parameter, if necessary. The calling code is responsible for preventing a buffer underflow of values ⁱⁿ.

This is the preferred way of updating a GPU buffer with ResourceAccessPattern.Dynamic access.

This method can also be used on GPU buffers with ResourceAccessPattern.Mappable access. In this case, the implementing class will transparently map the API calls to BufferMap, BufferPrepare and BufferUnmap.

See also: IGpuBuffer.ElementSize

BufferUpdateArray

public method BufferUpdateArray → (5)

first ⁱⁿ : int32: [>=0]
Index of the first 32-bit integer value in the buffer to update.
values ⁱⁿ : int32 [ ]: [not-null]
An array holding the updated 32-bit integer values.
offset ⁱⁿ : int32: [>=0]
Offset into values ⁱⁿ to first 32-bit integer value to read.
count ⁱⁿ : int32: [>=0]
Total number of 32-bit integer values to copy from values ⁱⁿ to this buffer.
flag ^opt : GpuUpdateFlag = GpuUpdateFlag.Discard: The update flag to apply.

Updates a range of 32-bit integer values in the buffer.

This method assumes that this buffer has an element size of 4 bytes. If the buffer has a different element size, it will return silently. This method is usually used in conjunction with IIndexBuffers, which always have an element size of 4 bytes.

This is the preferred way of updating a GPU buffer with ResourceAccessPattern.Dynamic access.

Public / Attributes

ElementSize

public attribute ElementSize → (get)

value : int32: [>=0]
The element size, in bytes; always a multiple of four. Will be 0 iff this buffer has an undefined structure and is used as a raw byte buffer. In this case, the capacity will give the buffer size in bytes (also always a multiple of four), instead of the element count.

The fixed element size of this buffer.