Remove the opengl-hq option default that caused it not to autoselect
ANGLE (unlike --vo=opengl). Details see commit d5df90a2.
Back then the intention was to use ANGLE by default, since it integrates
much nicer with the Windows compositor (instead of native OpenGL, which
tends to cause crazy glitches). On the other hand, many opengl-hq
capabilities are not available with older ANGLE builds, so it didn't
make any sense to autoselect ANGLE for it.
With the GL_EXT_texture_norm16 extension recently added to ANGLE, it has
essentially reached feature parity to desktop GL for the subset we are
using. (Even the integer texture hack for high bit depth input could be
dropped now.)
It (probably) still does not support nnedi3, due to the weird way the NN
coefficients are imported. Also, it uses half-floats instead of 16 bit
fixed-point textures for technical reasons, which implies about 5 bits
of precision loss. If anyone actually manages to distinguish the two
dithering texture formats in a double-blind test, I will fix it.
e5f49d9685