Using 8-bit integer math here lead to precision loss for depth copies,
which broke various effects in games, e.g. lens flare in MK:DD.
It's unlikely the console implements this as a floating-point multiply
(fixed-point perhaps), but since we have the float round trip in our
EFB2RAM shaders anyway, it's not going to make things any worse. If we
do rewrite our shaders to use integer math completely, then it might be
worth switching this conversion back to integers.
However, the range of the values (format) should be known, or we should
expand all values out to 24-bits first.
Also makes y_scale a dynamic parameter for EFB copies, as it doesn't
make sense to keep it as part of the uid, otherwise we're generating
redundant shaders.
This replaces usages of the non-standard __FUNCTION__ macro with the standard
mandated __func__ identifier.
__FUNCTION__ is a preprocessor definition that is provided as an
extension by compilers. This was the only convenient option to rely on
pre-C++11. However, C++11 and greater mandate the predefined identifier
__func__, which lets us accomplish the same thing.
The difference between the two, however, is that __func__ isn't a
preprocessor macro, it's an actual identifier that exists at function
scope. The C++17 draft standard (N4659) at section [dcl.fct.def.general]
paragraph 8 states:
"
The function-local predefined variable __func__ is defined as if a
definition of the form
static const char __func__[] = "function-name ";
had been provided, where function-name is an implementation-defined
string. It is unspecified whether such
a variable has an address distinct from that of any other object in the
program.
"
Thankfully, we don't do any macro or string concatenation with __FUNCTION__
that can't be modified to use __func__.
We now differentiate between a resize event and surface change/destroyed
event, reducing the overhead for resizes in the Vulkan backend. It is
also now now safe to change the surface multiple times if the video thread
is lagging behind.
This will generate one shader per copy format. For now, it is the same
shader with the colmat hard coded. So it should already improve the GPU
performance a bit, but a rewrite of the shader generator is suggested.
Half of the patch is done by linkmauve1:
VideoCommon: Reorganise the shader writes.
Techjar