Add Delegate and --log-graphics-calls flag (#334)

This adds a Delegate which enables users of the amber library to
define some hook functions as they like. The first usage here is a
Delegate::Log() function to log graphics API calls.

In practice, a pointer to the delegate object is passed at engine
creation and the Vulkan engine eventually pass it to
LoadVulkanPointers() which calls the functions produced by
update_vk_wrappers.py. This enable to choose, when loading the Vulkan
functions, whether to load a straighforward wrapper to the API
command, or to load a lambda that surround the API command with calls
to the delegate methods.

The --log-graphics-calls flag in the samples sets the delegate to
produce a log of API calls.

0 files changed, 0 insertions, 0 deletions