Nodes can have either a transform matrix, or decomposed transform
properties, but never both. Using a union means we can store both
of those variants in the same piece of memory, using the existing
matrix boolean to figure out which one to use.
This reduces the size of the struct by 48 bytes (152 -> 104), which
ends up speeding up some model operations, I'm guessing due to the
CPU cache.
Currently nobody returns data for them, though headset drivers could
start to provide poses estimated from the head pose and IPD info.
This also makes it easier to integrate eye tracking later.
The previous implementation relied on glShaderSource inferring source
lengths when the lengths weren't specified. This relies on the sources
being properly null-terminated, however, which isn't the case due to
file loading changes which now use pointer + length. This could cause
intermittent crashes.
Changing this on the shader side meant adding some extra arguments for
passing around shader source lengths. For most of the other cases, where
we're using string literals as the sources, we can just specify -1 as
the length, since OpenGL will calculate the string length for you any
time the length is negative.
This is a change that shifts the responsibility regarding the creation
of OpenGL framebuffers from vrapi-provided swapchain texture handles.
Previously, the LovrApp component of lovr-oculus-mobile was creating
framebuffers and passing native framebuffer IDs to lovr. With this
change, lovr-oculus-mobile passes vrapi's swapchain textures to lovr
unmodified. This allows lovr to create canvases using its conventional
method and also means that the properties of the canvases are no longer
hardcoded, so things like resolution and multisampling can be
customized.
There were also some issues with multiview canvases in LÖVR due to some
misconceptions about how multisampled multiview rendering works. These
issues have also been fixed in this commit.
Apparently requesting/rendering zero vertices was clogging stuff
somewhere. It seems good enough to just explicitly not render
anything if we weren't gonna do it anyway.
