Four review findings on the Task 7 renderer:
- InstanceStore::epoch() is derived from gl::Buffer::generation() -- advanced by
every allocation, deletion and move -- plus the slot the instances were written
to, so the orphan fallback of grow_persistent() can no longer leave the vertex
array's attribute pointers bound to a deleted buffer: the epoch reports the new
identity and upload() re-points them before the draw.
- PlotLayout reserves y_title_area/x_title_area outside axes (sized from the text
metrics) and draw_titles() draws in them, so a title can no longer land on the
data, whatever the envelope does.
- draw() computes plot.layout() once and hands it to the helpers, instead of six
times per frame, each of which rebuilt the ticks and the grid.
- A refused fence is no longer dropped: mark_drawn() falls back to the orphan path
and reports the failure rather than rotating through an unsynchronised slot.
New smoke cases force both refusals through the GL entry points (glMapBufferRange,
glFenceSync) and assert the pixels plus the live transfer mode; the title case
asserts the title colour is absent from the bands inside axes and present in both
strips. All three fail against the pre-fix sources.
- loader: add available(), true only after load() has resolved every
required entry point (false at the start of load()). Program::from_source
and the other fallible constructors return ErrorCode::Unsupported while it
is false, so a failed load() with a partially populated table can no longer
fault on an unresolved entry point.
- caps: GL_CONTEXT_PROFILE_MASK only exists from 3.2, so query it only on
3.2+ contexts. A 3.0/3.1 query latches GL_INVALID_ENUM in the context, which
the next unrelated glGetError() (e.g. read_pixel) then reports as failure.
- tests: gate the dlsym/libGL.so.1 fallback assertions on libGL being
resolvable, so the GL suite also passes on a GLES-only host.
Martino Ferrari