swung0x48/MobileGL
1
0
Fork 0
mirror of https://github.com/MobileGL-Dev/MobileGL synced 2026-09-11 21:58:31 +09:00
Code Issues Packages Projects Releases Wiki Activity

[Fix] (Pipe): key the framebuffer record to the object it names - a fourth Target value for every DSA entry point that hands a framebuffer over by name, and the metadata-only respecify the sticky bind mask needs

Browse Source
This commit is contained in:
swung0x48
2026-09-08 14:50:30 -04:00
parent 9ea44389e7
commit e8502a6100
2 changed files with 163 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files
MobileGL/MG_Pipe/MGPipeTypes.h
+129 -12
View File
@@ -298,9 +298,16 @@ namespace MobileGL::MG_Pipe {
Uint8 FixedSampleLocations, Immutable;
Uint32 Usage; // BufferUsage
Uint32 StorageFlags; // glBufferStorage flags
Uint8 HasDefinedContent; // false after a NULL-data respecify
Uint8 HasDefinedContent; // false after a NULL-data respecify - STORAGE-DEFINING
Uint8 ImageBindableHint; // client-side everImageBound; pre-emptive allocation
Uint16 Pad0;
// ImageBindableHint and BindMask above are the two METADATA fields the rule exists
// for: a respecify that moves only them - every storage-defining field equal to the
// stored descriptor - is a metadata update, with no reallocation ack and no
// PendingUploads clear. The rule, the full storage-defining field set and the third
// field allowed to differ (GlNameForDiag) are stated beside
// MGPipeResourceRespecifyNeedsAck below (P4a, ID-18 M4), which is where the applier
// and both twins read them from.
// Diagnostics only. A GL name is NEVER an identity, never a memo key and never part
// of a content hash (section 4.2.1). Widened from the plan's two bytes, which
// cannot hold one.
@@ -560,19 +567,52 @@ namespace MobileGL::MG_Pipe {
};
MGP_ASSERT_POD(MGPSurface, 24);
// P4a, D-C2/D-C3: the record is emitted PER BOUND TARGET.
// P4a, D-C2/D-C3 and ID-19: THE RECORD DESCRIBES A FRAMEBUFFER OBJECT, and Target says
// whether it ALSO moves a binding.
//
// GL has two independent framebuffer bindings and this record carries one Fbo and one
// ReadSurface, so Target says which binding it describes: 0 = Draw, 1 = Read, 2 = Both
// (one object bound to both targets). The draw-buffer array is applied only for a record
// whose Target is not Read - Espryt's own comment records the Minecraft 26.x OIT bug
// where a READ-only sync landed glDrawBuffers on the wrong framebuffer - and ReadSurface
// is resolved from the READ framebuffer's own read buffer, which is what makes the
// read-buffer-shared-FBO defect class unrepresentable rather than merely fixed.
// A `Named` record describes the framebuffer object it names (Fbo) and changes NO
// binding. `Draw` / `Read` / `Both` records describe the same object AND set the bound
// handle(s) of the target(s) they name.
//
// The applier therefore keeps records PER FRAMEBUFFER OBJECT, keyed by the handle's slot
// (the generation is checked on lookup and a stale one refuses; a framebuffer has no wire
// lifetime - D-I2, the catalogue has no framebuffer delete - so a successor's record
// simply OVERWRITES the slot), plus the two bound handles. And every DSA entry point that
// hands a framebuffer to the server BY NAME - BlitNamedFramebuffer, the four
// ClearNamedFramebuffer*, and the DSA attachment / draw-buffer / read-buffer setters at
// their validate point - is PRECEDED BY A Named RECORD, so that any framebuffer the
// server is about to receive by name already has one.
//
// That last rule is the phase's main correction, not a nicety. With only the two
// bound-target records, glClearNamedFramebufferfv(fbo) on an unbound fbo made the backend
// mint a fresh driver framebuffer with NO ATTACHMENTS, find no record for it, decline,
// and then issue the clear against it anyway - GL_INVALID_FRAMEBUFFER_OPERATION and
// nothing cleared, where the legacy arm cleared correctly. Writing such an object into
// the bound-target record instead would have been worse: the applier would then claim it
// is bound.
//
// GL has two independent framebuffer bindings and one record carries one Fbo, so a
// Draw/Read pair is two records and one object bound to both targets is one record with
// Both. The draw-buffer array belongs to the OBJECT the record names; it reaches the
// driver's bound draw framebuffer only for a record whose Target is Draw or Both -
// Espryt's own comment records the Minecraft 26.x OIT bug where a READ-only sync landed
// glDrawBuffers on the wrong framebuffer - and a Named record's draw buffers are applied
// when that object is next configured, never to whatever happens to be bound. ReadSurface
// is resolved from THAT framebuffer's own read buffer in EVERY record, Named included,
// which is what makes the read-buffer-shared-FBO defect class unrepresentable rather than
// merely fixed.
//
// Target IS A ContentHash INPUT (the hash covers the whole record), and the emitter's
// suppressor must be keyed by the framebuffer the record names, not by one global slot:
// two different objects' Named records in a row must both go out, and a Named record must
// never be suppressed against the same object's bound record or the reverse.
enum class MGPipeFramebufferTarget : Uint8 {
Draw = 0,
Read = 1,
Both = 2,
// Describes the framebuffer named by Fbo and changes no binding (ID-19). Emitted
// ahead of every DSA entry point that hands that framebuffer over by name.
Named = 3,
Count,
};
@@ -589,14 +629,48 @@ namespace MobileGL::MG_Pipe {
static_assert(kMGPipeMaxColorAttachments == MobileGL::kMGMaxDrawBuffers,
"MGPFramebufferState::Color[] and DrawBuffers[] are one array width");
// ONE RECORD DESCRIBES ONE FRAMEBUFFER OBJECT - the one named by Fbo - and Target says
// whether it also moves a binding (P4a, D-C2 as corrected by ID-19; see
// MGPipeFramebufferTarget above for the failure that forced it).
//
// A Named record describes that object and changes NO binding. Draw / Read / Both records
// describe that object AND set the bound handle(s) of the target(s) they name. The applier
// keeps these records PER FRAMEBUFFER OBJECT, keyed by Fbo's slot (generation checked on
// lookup; a framebuffer has no wire lifetime - D-I2 - so a successor's record simply
// overwrites the slot), plus the two bound handles; every DSA entry point that hands a
// framebuffer to the server by name is preceded by a Named record.
//
// WHAT Target CHANGES, FIELD BY FIELD. NO FIELD IN THIS RECORD REFERS TO "the currently
// bound framebuffer" - every one of them describes the object named by Fbo - and that is
// the invariant a reader depends on:
//
// Fbo, Color[], Depth, Stencil, ReadSurface, Width/Height/Layers/Samples,
// FixedSampleLocations, IsDefault, Complete
// properties of the object named by Fbo, identical in meaning under every Target.
// In particular ReadSurface is resolved from THAT framebuffer's own read buffer -
// on a Named record too - never from whichever framebuffer is bound to GL_READ.
// DrawBuffers[]
// a property of the named object; it reaches the driver's bound draw framebuffer
// only when Target is Draw or Both. Under Named it is stored with the object and
// applied when that object is next configured.
// Target
// the only binding-specific field: Draw/Read/Both name the binding(s) this record
// also sets, Named names none. It is a ContentHash input.
// ContentHash
// per RECORD, not per object, and the emitter's suppressor is keyed by the
// framebuffer named: a Named record must never be suppressed against the same
// object's bound record, nor one object's Named record against another's.
struct MGPFramebufferState {
MGPipeHandle Fbo; // kMGPipeDefaultFramebuffer for the default framebuffer
MGPSurface Color[8];
MGPSurface Depth, Stencil;
// The RESOLVED read surface, not an index. This is what structurally closes the
// The RESOLVED read surface, not an index, and it is THIS framebuffer's own read
// buffer under every Target - Named included. This is what structurally closes the
// read-buffer-shared-FBO defect class.
MGPSurface ReadSurface;
Int8 DrawBuffers[8]; // attachment index, -1 = NONE
// attachment index, -1 = NONE. The named object's array; applied to the bound draw
// framebuffer only when Target is Draw or Both.
Int8 DrawBuffers[8];
Uint16 Width, Height, Layers, Samples;
// Complete is FramebufferObject::CheckCompleteness(), the frontend-only answer - NOT
// glCheckFramebufferStatus's. CheckFramebufferStatus_State additionally consults
@@ -607,12 +681,15 @@ namespace MobileGL::MG_Pipe {
// answer, and glCheckFramebufferStatus keeps answering from the frontend as it does
// today.
Uint8 FixedSampleLocations, IsDefault, Complete;
Uint8 Target; // MGPipeFramebufferTarget, above (P4a, D-C2; was Pad0)
// MGPipeFramebufferTarget, above (P4a, D-C2; was Pad0). Draw/Read/Both also set the
// named binding(s); Named sets none (ID-19). The ONLY binding-specific field.
Uint8 Target;
Uint32 Pad1;
// Two jobs (section 4.5.6): the server's render-pass memo key, and the CLIENT's
// emission suppressor - an unchanged hash means this record is not sent at all.
// The same pattern is mandatory for every kVarTail set_* below, or 26.2's
// redundant glBindSampler traffic reappears as a variable-length record per batch.
// Target is one of its inputs, and the suppressor is keyed per framebuffer.
Uint64 ContentHash;
};
MGP_ASSERT_POD(MGPFramebufferState, 304);
@@ -1008,6 +1085,46 @@ namespace MobileGL::MG_Pipe {
return desc.Immutable != 0 && desc.Target == kMGPipeResourceTargetBuffer;
}
// P4a, ID-18 M4: A RESPECIFY WHOSE STORAGE-DEFINING FIELDS ALL EQUAL THE STORED
// DESCRIPTOR IS A METADATA UPDATE, NOT A REALLOCATION.
//
// MGPResourceDesc::BindMask and ImageBindableHint are STICKY facts the client discovers
// AFTER allocation - a texture first bound as a shader image, first used as a render
// target - and they ride resource_create and every resource_respecify. An IMMUTABLE
// texture never has a later respecify, so without a rule those two would reach the server
// only by accident, or never; with one, a mask change after allocation emits a
// resource_respecify that REPEATS the storage the resource already has.
//
// The applier and both twins must classify such a record as a metadata update:
// - NO reallocation acknowledgement. MGPipeResourceRespecifyNeedsAck above still
// answers the per-record question, but a metadata update allocates nothing, so a
// record it classifies as metadata is not acked even when that predicate says the
// call may require one.
// - NO PendingUploads clear - not the whole vector, and not the redefined level either.
// This REFINES the level-scoped clear: identical storage fields clear NOTHING. (The
// level-scoped rule exists because clearing the whole vector on a level-1 definition
// silently dropped level 0's accepted texels; a metadata update must drop neither.)
// - The stored descriptor's BindMask and ImageBindableHint ARE updated - BindMask is
// sticky and therefore ORed, never replaced - and the twin re-derives its storage
// flags from the new mask on its next sync, recreating backend storage only where the
// backend actually needs it. The record itself is not a request to recreate.
//
// THE STORAGE-DEFINING FIELD SET, named here so that neither side has to guess and a
// later field cannot join it by silence. It is every MGPResourceDesc member except the
// three metadata ones and the padding:
//
// Target, StorageKind, InternalFormat, Width, Height, Depth, ArrayLayers, Levels,
// Samples, FixedSampleLocations, Immutable, Usage, StorageFlags, HasDefinedContent,
// ViewOf, BufferForTexBuffer, BufOffset, BufSize.
//
// `Resource` is the identity the stored descriptor is looked up BY, not a comparand. The
// three fields that may differ on a metadata update are exactly BindMask,
// ImageBindableHint and GlNameForDiag (diagnostics only, never an identity, never a memo
// key). HasDefinedContent is storage-defining ON PURPOSE: glBufferData(size, NULL) at an
// unchanged size is an orphaning reallocation and has to keep clearing, rather than being
// mistaken for a mask change. A field added to MGPResourceDesc must be placed in one of
// the two lists in the same commit - PipeCatalogue pins the struct's size for that.
// The forward terminator for a server-initiated texture pull (section 7.1). May carry
// zero regions - that is how a pull that needs nothing is answered.
struct MGPSubDataComplete {