* avoid undefined behavior from UNREACHABLE on reachable code paths
UNREACHABLE expands to __assume(false) / __builtin_unreachable() in
release builds, which is undefined behavior if the code is ever actually
reached. Many UNREACHABLE sites only guard against unexpected-but-
possible runtime states (values from tables, mission/save files, network
packets, scripting, or user input), so reaching them should degrade
gracefully rather than invoke UB.
Replace UNREACHABLE with Assertion(false, ...) at all such sites. It
still pops an error in debug builds, but in release it is a harmless
no-op that simply falls through to the following code. Sites that are
genuinely unreachable by local invariants (e.g. a switch over a bounded
random number) are left as UNREACHABLE.
A few converted sites had no safe fall-through -- an uninitialized read,
null dereference, or null call would have followed -- so they also get a
minimal recovery: initialize the value, guard the dereference, return
early, or skip the offending item.
Where the converted site was a simple guard of the form
if (x) { Assertion(false, ...); return; }
hoist the check onto the invariant instead:
Assertion(!x, ...);
if (x) { return; }
This states the expectation directly and shows the offending value in
the debug popup, while keeping the same graceful runtime degradation.
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
* addendum
After consultation with Lafiel, use UNREACHABLE in situations that are effectively impossible even if not provably impossible. UNREACHABLE = "this shouldn't ever happen"; Assertion = "if this ever happens, it's a coding error". Also fix a few other sites and change a couple to Warnings.
---------
Co-authored-by: Claude Opus 4.8 (1M context) <[email protected]>
This was causing issues when using the new scripting API in JAD where
there were a lot of 2D operations which filled up the immediate mode
buffer. The reason was that GL_ARB_vertex_attrib_binding the relative
offset is limited and the movie code adds the immediate buffer offset to
the vertex layout which then hit the offset limit set by OpenGL.
This fixes that by using the normal byte offset method which is already
used by the render_primitives functions.
This allows to directly display RGB(A) movies without transcoding them
to YUV first. This allows the movie player to support APNG files (which
are supported natively by FFmpeg) with an alpha channel and without
converting them to YUV first.
This moves all the cutscene specific code out of the movie player code
and into the cutscene code so that the movie player can be reused for
usage in other environments.
This is required for #1041 since an implementation of that feature would
reuse the movie player code of the cutscene code but without all the
main loop stuff.
There is nothing specific to OpenGL in that code anymore since it's all
handled in the shaders at this point. This will make the lighting
information available in the normal graphics code which allows to use
those values when filling the uniform buffer for the model rendering.
All transformations are now handled by shaders so there is nothing
special going on in the graphics API specific code anymore. Since model
uniform buffers require access to these matrices I moved the matrix
handling out of the graphics API code.
This converts the deferred lighting shader to use uniform buffers for
the dynamic data sent to the GPU while rendering the lighting effects.
This doesn't affect performance but the deferred lighting code is a
nicely isolated piece of rendering code where I could test how the
rendering code could use the uniform buffers.
This is related to #910.
This converts all usages of bmpman textures to OpenGL texture arrays.
That means that all frames of an animation are stored in a single OpenGL
texture object and can be accessed at the same time in a single draw
call. This should significantly reduce the overhead of drawing lots of
particles since all particles of a single animation can be drawn with a
single draw call.
This fixes#1169.
