Fixed-capacity ring buffer of GL textures for temporal shaders. More...

Public Member Functions
std::size_t	capacity () const
	Maximum number of frames retained by the ring.
void	cleanup ()
	Release all GL textures and reset the ring state.
void	fill (const cv::Mat &frame)
	Pre-fill every slot with copies of a single frame.
	FrameCache (const FrameCache &)=delete
	FrameCache (std::size_t num, bool use_array=false)
GLuint	historyTexture () const
	Array texture containing the physical history ring layers.
void	init (int w, int h, bool hdr=false)
	Allocate the ring of GL textures sized to `w` x `h`.
bool	isFull () const
	True when the ring is fully populated.
int	oldestLayer () const
	Physical array layer corresponding to logical history index zero.
FrameCache &	operator= (const FrameCache &)=delete
void	push (const cv::Mat &frame)
	Upload `frame` (BGR) into the next ring slot.
void	pushFromFBO (GLuint src_fbo, int w, int h)
	GPU-side push from a source FBO into the next ring slot.
void	pushFromTexture (GLuint src_tex, int w, int h)
	GPU-side push from an existing GL texture into the next ring slot.
std::size_t	size () const
	Number of frames currently retained (0 ≤ n ≤ capacity).
GLuint	textureAt (std::size_t index) const
	Return the GL texture at logical index `index`.
	~FrameCache ()

Private Member Functions
void	advance ()
void	allocateHistoryTexture ()
	Allocate the optional array texture using the cache's dimensions and pixel format.
void	finishPush ()
bool	hasStorage () const

Private Attributes
std::size_t	count = 0
std::size_t	head = 0
int	height = 0
GLuint	history_texture = 0
	Optional array-backed history ring.
bool	is_hdr = false
std::size_t	num_frames
GLuint	scratch_fbo = 0
	Scratch FBO used by pushFromTexture().
std::vector< GLuint >	textures
bool	use_history_array = false
int	width = 0

Detailed Description

Fixed-capacity ring buffer of GL textures for temporal shaders.

Legacy shaders whose filename contains "cache" receive previous frames as separate sampler2D uniforms. Array-cache shaders instead receive one sampler2DArray whose layers form the ring. In either mode only the newest frame is uploaded into the next physical slot. The "oldest → newest" indexing used by shaders is preserved via a logical-to-physical offset.

This mirrors the texture-ring approach used by gl_compute_cv and eliminates 7 BGR→RGBA conversions plus 7 texture uploads per push.

Definition at line 2052 of file ACMX2/acmx.cpp.

Constructor & Destructor Documentation

◆ FrameCache() [1/2]

FrameCache::FrameCache	(	std::size_t	num,
		bool	use_array = false )

inlineexplicit

Parameters

num	Maximum number of frames to retain.
use_array	Store the ring in one GL_TEXTURE_2D_ARRAY instead of separate GL_TEXTURE_2D objects.

Definition at line 2059 of file ACMX2/acmx.cpp.

References num_frames, and use_history_array.

Referenced by FrameCache(), and operator=().

◆ ~FrameCache()

FrameCache::~FrameCache ( )

inline

Definition at line 2060 of file ACMX2/acmx.cpp.

References cleanup().

◆ FrameCache() [2/2]

FrameCache::FrameCache ( const FrameCache & )

delete

References FrameCache().

Member Function Documentation

◆ advance()

void FrameCache::advance ( )

inlineprivate

Definition at line 2382 of file ACMX2/acmx.cpp.

References count, head, and num_frames.

Referenced by finishPush(), and push().

◆ allocateHistoryTexture()

void FrameCache::allocateHistoryTexture ( )

inlineprivate

Allocate the optional array texture using the cache's dimensions and pixel format.

Definition at line 2401 of file ACMX2/acmx.cpp.

References height, history_texture, is_hdr, num_frames, use_history_array, and width.

Referenced by fill(), init(), pushFromFBO(), and pushFromTexture().

◆ capacity()

std::size_t FrameCache::capacity ( ) const

inline

Maximum number of frames retained by the ring.

Definition at line 2324 of file ACMX2/acmx.cpp.

References num_frames.

◆ cleanup()

void FrameCache::cleanup ( )

inline

Release all GL textures and reset the ring state.

Definition at line 2111 of file ACMX2/acmx.cpp.

References count, head, height, history_texture, is_hdr, scratch_fbo, textures, and width.

Referenced by init(), and ~FrameCache().

◆ fill()

void FrameCache::fill ( const cv::Mat & frame )

inline

Pre-fill every slot with copies of a single frame.

Seeds the entire cache with one frame and marks the ring as full.

Definition at line 2340 of file ACMX2/acmx.cpp.

References allocateHistoryTexture(), count, hasStorage(), head, height, history_texture, num_frames, textures, use_history_array, and width.

Referenced by push().

◆ finishPush()

void FrameCache::finishPush ( )

inlineprivate

Definition at line 2388 of file ACMX2/acmx.cpp.

References advance(), count, head, and num_frames.

Referenced by pushFromFBO(), and pushFromTexture().

◆ hasStorage()

bool FrameCache::hasStorage ( ) const

inlineprivate

Definition at line 2380 of file ACMX2/acmx.cpp.

References history_texture, textures, and use_history_array.

Referenced by fill(), push(), pushFromFBO(), and pushFromTexture().

◆ historyTexture()

GLuint FrameCache::historyTexture ( ) const

inline

Array texture containing the physical history ring layers.

Definition at line 2330 of file ACMX2/acmx.cpp.

References history_texture.

Referenced by ACView::bindPassHistoryTextures().

◆ init()

void FrameCache::init	(	int	w,
		int	h,
		bool	hdr = false )

inline

Allocate the ring of GL textures sized to w x h.

Must be called once a GL context is current. Existing textures (if any) are released first. The ring remains empty until the first source frame is replicated into every slot by one of the push methods.

Parameters

w	Texture width in pixels.
h	Texture height in pixels.
hdr	When true, allocate textures as `GL_RGBA16F` (matching the HDR linear-light pipeline) instead of `GL_RGBA`.

Definition at line 2077 of file ACMX2/acmx.cpp.

References allocateHistoryTexture(), cleanup(), count, head, height, is_hdr, num_frames, textures, use_history_array, and width.

◆ isFull()

bool FrameCache::isFull ( ) const

inline

True when the ring is fully populated.

Definition at line 2327 of file ACMX2/acmx.cpp.

References count, and num_frames.

Referenced by ACView::bindPassHistoryTextures(), and oldestLayer().

◆ oldestLayer()

int FrameCache::oldestLayer ( ) const

inline

Physical array layer corresponding to logical history index zero.

Definition at line 2333 of file ACMX2/acmx.cpp.

References head, and isFull().

◆ operator=()

FrameCache & FrameCache::operator= ( const FrameCache & )

delete

References FrameCache().

◆ push()

void FrameCache::push ( const cv::Mat & frame )

inline

Upload frame (BGR) into the next ring slot.

When the ring is full this overwrites the oldest slot in place, which becomes the new "newest" frame. Only one BGR→RGBA conversion and one texture upload occur per call.

Definition at line 2209 of file ACMX2/acmx.cpp.

References advance(), count, fill(), hasStorage(), head, height, history_texture, textures, use_history_array, and width.

◆ pushFromFBO()

void FrameCache::pushFromFBO	(	GLuint	src_fbo,
		int	w,
		int	h )

inline

GPU-side push from a source FBO into the next ring slot.

Used by the HDR pipeline to copy the post-decode linear BT.2020 texture into an RGBA16F ring without any CPU readback or pixel format conversion. The source FBO must have a colour attachment sized at least w x h and using a compatible internal format (e.g. GL_RGBA16F when the cache was initialised with hdr=true).

Parameters

src_fbo	Read framebuffer object containing the new frame.
w,h	Region to copy (typically the full FBO dimensions).

Definition at line 2143 of file ACMX2/acmx.cpp.

References allocateHistoryTexture(), count, finishPush(), hasStorage(), head, height, history_texture, is_hdr, num_frames, textures, use_history_array, and width.

◆ pushFromTexture()

void FrameCache::pushFromTexture	(	GLuint	src_tex,
		int	w,
		int	h )

inline

GPU-side push from an existing GL texture into the next ring slot.

Uses a small scratch FBO so the per-frame BGR->RGBA conversion and second host->GPU upload that push() performs can be avoided entirely once the camera texture has already been populated for the shader chain. This is the path that keeps zero-copy interop intact when expensive CPU passes (e.g. ONNX) run earlier in the frame and the redundant cv::Mat upload starts dropping frames.

Parameters

src_tex	GL texture currently containing the new frame.
w,h	Region to copy (typically the full texture size).

Definition at line 2245 of file ACMX2/acmx.cpp.

References allocateHistoryTexture(), count, finishPush(), hasStorage(), head, height, history_texture, is_hdr, num_frames, scratch_fbo, textures, use_history_array, and width.

◆ size()

std::size_t FrameCache::size ( ) const

inline

Number of frames currently retained (0 ≤ n ≤ capacity).

Definition at line 2321 of file ACMX2/acmx.cpp.

References count.

◆ textureAt()

GLuint FrameCache::textureAt ( std::size_t index ) const

inline

Return the GL texture at logical index index.

Parameters

index 0 = oldest retained frame, size()-1 = newest.

Definition at line 2315 of file ACMX2/acmx.cpp.

References count, head, num_frames, and textures.

Referenced by ACView::bindPassHistoryTextures().

Member Data Documentation

◆ count

std::size_t FrameCache::count = 0

private

Definition at line 2424 of file ACMX2/acmx.cpp.

Referenced by advance(), cleanup(), fill(), finishPush(), init(), isFull(), push(), pushFromFBO(), pushFromTexture(), size(), and textureAt().

◆ head

std::size_t FrameCache::head = 0

private

Definition at line 2423 of file ACMX2/acmx.cpp.

Referenced by advance(), cleanup(), fill(), finishPush(), init(), oldestLayer(), push(), pushFromFBO(), pushFromTexture(), and textureAt().

◆ height

int FrameCache::height = 0

private

Definition at line 2420 of file ACMX2/acmx.cpp.

Referenced by allocateHistoryTexture(), cleanup(), fill(), init(), push(), pushFromFBO(), and pushFromTexture().

◆ history_texture

GLuint FrameCache::history_texture = 0

private

Optional array-backed history ring.

Definition at line 2427 of file ACMX2/acmx.cpp.

Referenced by allocateHistoryTexture(), cleanup(), fill(), hasStorage(), historyTexture(), push(), pushFromFBO(), and pushFromTexture().

◆ is_hdr

bool FrameCache::is_hdr = false

private

Definition at line 2421 of file ACMX2/acmx.cpp.

Referenced by allocateHistoryTexture(), cleanup(), init(), pushFromFBO(), and pushFromTexture().

◆ num_frames

std::size_t FrameCache::num_frames

private

Definition at line 2418 of file ACMX2/acmx.cpp.

Referenced by advance(), allocateHistoryTexture(), capacity(), fill(), finishPush(), FrameCache(), init(), isFull(), pushFromFBO(), pushFromTexture(), and textureAt().

◆ scratch_fbo

GLuint FrameCache::scratch_fbo = 0

private

Scratch FBO used by pushFromTexture().

Definition at line 2426 of file ACMX2/acmx.cpp.

Referenced by cleanup(), and pushFromTexture().

◆ textures

std::vector<GLuint> FrameCache::textures

private

Definition at line 2425 of file ACMX2/acmx.cpp.

Referenced by cleanup(), fill(), hasStorage(), init(), push(), pushFromFBO(), pushFromTexture(), and textureAt().

◆ use_history_array

bool FrameCache::use_history_array = false

private

Definition at line 2422 of file ACMX2/acmx.cpp.

Referenced by allocateHistoryTexture(), fill(), FrameCache(), hasStorage(), init(), push(), pushFromFBO(), and pushFromTexture().

◆ width

int FrameCache::width = 0

private

Definition at line 2419 of file ACMX2/acmx.cpp.

Referenced by allocateHistoryTexture(), cleanup(), fill(), init(), push(), pushFromFBO(), and pushFromTexture().

The documentation for this class was generated from the following file:

ACMX2/acmx.cpp

ACMX 2.139.0 Dual-Backend Real-Time GPU Video Synthesis

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ FrameCache() [1/2]

◆ ~FrameCache()

◆ FrameCache() [2/2]

Member Function Documentation

◆ advance()

◆ allocateHistoryTexture()

◆ capacity()

◆ cleanup()

◆ fill()

◆ finishPush()

◆ hasStorage()

◆ historyTexture()

◆ init()

◆ isFull()

◆ oldestLayer()

◆ operator=()

◆ push()

◆ pushFromFBO()

◆ pushFromTexture()

◆ size()

◆ textureAt()

Member Data Documentation

◆ count

◆ head

◆ height

◆ history_texture

◆ is_hdr

◆ num_frames

◆ scratch_fbo

◆ textures

◆ use_history_array

◆ width