},
[this, face, level, x, y, wd, ht](VkCommandBuffer cmd_buf, VkBuffer staging_buf, size_t src_off){
const VulkanFunctions &vk = device.get_functions();
VkBufferImageCopy region = { };
region.bufferOffset = src_off;
},
[this, face, level, x, y, wd, ht](VkCommandBuffer cmd_buf, VkBuffer staging_buf, size_t src_off){
const VulkanFunctions &vk = device.get_functions();
VkBufferImageCopy region = { };
region.bufferOffset = src_off;