Video

Manage window creation and pixel-based drawing. More...

Collaboration diagram for Video:

Detailed Description

The video API provides an abstraction for creating and managing platform-specific windows and their framebuffers. It supports event polling, framebuffer rendering, and resizing operations.

Each video backend implements this interface.

Data Structures
struct	bj_video_layer_t
	Structure describing a video layer backend. More...
struct	bj_video_layer_create_info
	Structure used to declare a video backend implementation. More...

Typedefs
typedef void(*	bj_window_end_fn_t) (struct bj_video_layer_t *p_layer, bj_error **p_error)
	Define a function used to terminate a video layer.
typedef bj_window *(*	bj_window_create_window_fn_t) (struct bj_video_layer_t *p_layer, const char *title, uint16_t x, uint16_t y, uint16_t width, uint16_t height, uint8_t flags)
	Define a function used to create a new window.
typedef void(*	bj_window_delete_window_fn_t) (struct bj_video_layer_t *p_layer, bj_window *p_window)
	Define a function used to destroy an existing window.
typedef void(*	bj_window_poll_events_fn_t) (struct bj_video_layer_t *p_layer)
	Define a function used to poll events for all windows.
typedef int(*	bj_window_get_size_fn_t) (struct bj_video_layer_t *p_layer, const bj_window *p_window, int *p_width, int *p_height)
	Define a function used to retrieve the size of a window.
typedef bj_bitmap *(*	bj_window_create_framebuffer_fn_t) (struct bj_video_layer_t *p_layer, const bj_window *p_window, bj_error **p_error)
	Define a function used to create a framebuffer for a window.
typedef void(*	bj_window_flush_framebuffer_fn_t) (struct bj_video_layer_t *p_layer, const bj_window *p_window)
	Define a function used to present a framebuffer to the window surface.
typedef struct bj_video_layer_t	bj_video_layer
	Structure describing a video layer backend.

---

Data Structure Documentation

bj_video_layer_t

struct bj_video_layer_t

This contains all the function pointers that define the backend behavior, as well as backend-specific data.

See also

bj_video_layer_create_info

Collaboration diagram for bj_video_layer_t:

Data Fields
bj_window_create_window_fn_t	create_window	Create a window.
bj_window_create_framebuffer_fn_t	create_window_framebuffer	Create a framebuffer.
struct bj_video_layer_data_t *	data	Backend-specific data.
bj_window_delete_window_fn_t	delete_window	Delete a window.
bj_window_end_fn_t	end	Terminate the video layer.
bj_window_flush_framebuffer_fn_t	flush_window_framebuffer	Present framebuffer.
bj_window_get_size_fn_t	get_window_size	Retrieve window dimensions.
bj_window_poll_events_fn_t	poll_events	Poll window events.

bj_video_layer_create_info

struct bj_video_layer_create_info

This is registered during initialization to allow choosing the appropriate video layer at runtime.

See also

bj_video_layer

Collaboration diagram for bj_video_layer_create_info:

Data Fields
bj_video_layer *(*)(bj_error **p_error)	create	Function to create the backend.
const char *	name	Name of the video backend.

Typedef Documentation

bj_video_layer

typedef struct bj_video_layer_t bj_video_layer

This contains all the function pointers that define the backend behavior, as well as backend-specific data.

See also

bj_video_layer_create_info

bj_window_create_framebuffer_fn_t

typedef bj_bitmap *(* bj_window_create_framebuffer_fn_t) (struct bj_video_layer_t *p_layer, const bj_window *p_window, bj_error **p_error)

The framebuffer is a pixel buffer that can be written to by the application and later flushed to the screen.

Parameters

p_layer	Pointer to the video layer.
p_window	Target window.
p_error	Output error pointer.

Returns

A pointer to the new framebuffer, or NULL on error.

See also

bj_bitmap, bj_window

bj_window_create_window_fn_t

typedef bj_window *(* bj_window_create_window_fn_t) (struct bj_video_layer_t *p_layer, const char *title, uint16_t x, uint16_t y, uint16_t width, uint16_t height, uint8_t flags)

Parameters

p_layer	Pointer to the video layer.
title	Title of the window.
x	Initial x position of the window.
y	Initial y position of the window.
width	Width of the window in pixels.
height	Height of the window in pixels.
flags	Window creation flags.

Returns

A pointer to the created window, or NULL on failure.

See also

bj_window, bj_video_layer

bj_window_delete_window_fn_t

typedef void(* bj_window_delete_window_fn_t) (struct bj_video_layer_t *p_layer, bj_window *p_window)

Parameters

p_layer	Pointer to the video layer.
p_window	Window to destroy.

See also

bj_window

bj_window_end_fn_t

typedef void(* bj_window_end_fn_t) (struct bj_video_layer_t *p_layer, bj_error **p_error)

This function is called to release all resources associated with the layer.

Parameters

p_layer	Pointer to the video layer.
p_error	Output error pointer.

See also

bj_video_layer

bj_window_flush_framebuffer_fn_t

typedef void(* bj_window_flush_framebuffer_fn_t) (struct bj_video_layer_t *p_layer, const bj_window *p_window)

This is typically called after rendering to the framebuffer.

Parameters

p_layer	Pointer to the video layer.
p_window	Target window.

See also

bj_window, bj_bitmap

bj_window_get_size_fn_t

typedef int(* bj_window_get_size_fn_t) (struct bj_video_layer_t *p_layer, const bj_window *p_window, int *p_width, int *p_height)

Parameters

p_layer	Pointer to the video layer.
p_window	Target window.
p_width	Output width in pixels.
p_height	Output height in pixels.

Returns

1 on success, 0 on failure.

See also

bj_window

bj_window_poll_events_fn_t

typedef void(* bj_window_poll_events_fn_t) (struct bj_video_layer_t *p_layer)

Parameters

p_layer

Pointer to the video layer.

See also

bj_dispatch_events