It uses newPass instead of getPass. Temporary objects had lifetime
issues that were nearly impossible to solve. And normal objects are
easier to understand because they behave like all other LÖVR objects.
However, Pass commands are not retained from frame to frame. Pass
objects must be re-recorded before every submit, and must be reset
before being recorded again.
Pass objects now provide a natural place for render-pass-related info
like clears and texture handles. They also allow more information to be
precomputed which should reduce overhead a bit.
It is now possible to request a stencil buffer and antialiasing on the
window and headset textures, via conf.lua.
lovr.graphics.setBackground should instead set the clear color on the
window pass. Though we're still going to try to do spherical harmonics
in some capacity.
There are still major issues with OpenXR that are going to be ironed
out, and the desktop driver hasn't been converted over to the new
headset Pass system yet. So lovr.headset integration is a bit WIP.
There are some issues with immediately tracking readbacks in the global
linked list of pending readbacks:
- The Pass might not get submitted, in which case the readback will be
"dangling" and never complete (or it will erroneously think it's
completed but its buffer will contain garbage data).
- Thread safety issues of modifying a global data structure from a Pass.
Instead, Pass will locally track the readbacks it performs, and only at
submit time will those readbacks get added to the global list.
(There is a little bit of refcounting mistakes now, those will get
cleaned up).
- Rename/reorder some projection matrix functions.
- Make perspective functions flip Y and use 0-1 NDC range.
- Flip winding and font vertices based on handedness.
This stuff is really confusing
Pass stores a small 16-bucket cache of vertices/indices it recently
generated. Draws that have relatively predictable geometry can provide
a hash along with their draw. The Pass will reuse vertices based on the
hash, when possible, and return a NULL vertex pointer to let the draw-er
know they don't need to generate any vertices.
This provides a dramatic speedup when drawing the same shape many times
in a row. The overhead is negligible, with benefits kicking in with
just a small handful of repeated draws (3-5 for cubes, less for more
complex shapes).
Originally we made the font texture f16 due to "clamping" of the
distance field, and kept it as floats (but f32 since conversion isn't
automatic with Vulkan) here. However, clamping isn't really an issue.
You can increase the spread of the font to literally get a wider spread
of the SDF for glows, etc. Switching to u8 uses 4x less texture memory,
which is significant.
It can be used to push the current cursor onto the stack, perform some
tmep allocations, and then pop the stack to "free" them all at once.
This can be nice if you're doing some temporary allocations that aren't
going to be needed when the function returns, since it reduces the
amount of allocator growth a bit.
This allocator is meant to be threadlocal eventually, so there are no
thread-safety concerns.
- Padding is automatically computed from spread.
- Spread increases detail at small sizes.
- Remove failure cases where padding < spread/2
- UVs are un16x2, making room for color
- Don't center glyphs inside their atlas bounding box
- Cache normalized UVs and update them (for glyphs and vertices) when
the atlas changes size.
- Updating the UVs is UGLY and duplicates a lot of code. It may be
better to normalize the UVs on the fly, or just re-render the entire
string if the atlas is updated.