## 17.4. Filling Buffers

To clear buffer data, call:

    void vkCmdFillBuffer(
        VkCommandBuffer                             commandBuffer,
        VkBuffer                                    dstBuffer,
        VkDeviceSize                                dstOffset,
        VkDeviceSize                                size,
        uint32_t                                    data);

- `commandBuffer` is the command buffer into which the command will be recorded.
- `dstBuffer` is the buffer to be filled.
- `dstOffset` is the byte offset into the buffer at which to start filling, and must be a multiple of 4.
- `size` is the number of bytes to fill, and must be either a multiple of 4, or `VK_WHOLE_SIZE` to fill the range from `offset` to the end of the buffer. If `VK_WHOLE_SIZE` is used and the remaining size of the buffer is not a multiple of 4, then the nearest smaller multiple is used.
- `data` is the 4-byte word written repeatedly to the buffer to fill `size` bytes of data. The data word is written to memory according to the host endianness.

`vkCmdFillBuffer` is treated as “transfer” operation for the purposes of synchronization barriers. The `VK_BUFFER_USAGE_TRANSFER_DST_BIT` must be specified in `usage` of `VkBufferCreateInfo` in order for the buffer to be compatible with `vkCmdFillBuffer`.