Struct gbm_rs::Surface

pub struct Surface { /* fields omitted */ }

Analogous to gbm_surface

Represents an area where a buffer object will be displayed.

Methods

impl Surface

fn new(
    dev: &Device,
    width: u32,
    height: u32,
    format: u32,
    flags: u32
) -> Option<Surface>

Allocate a Surface object

Arguments

dev: The Device returned from Device::from_fd()

width: The width for the surface

height: The height for the surface

format: The fourcc code for the surface

flags: A bitmask of the flags for this surface

Returns

A newly allocated surface. If an error occurs during allocation None will be returned.

Example

let surface = gbm::Surface::new(&device, 1920, 1080,
                                gbm::format::XRGB8888, // GBM_FORMAT_XRGB8888
                                gbm::USE_SCANOUT | gbm::USE_RENDERING).unwrap();

fn has_free_buffers(&self) -> bool

Returns whether or not a surface has free (non-locked) buffers

Before starting a new frame, the surface must have a buffer available for rendering. Initially, a gbm surface will have a free buffer, but after one of more buffers have been locked, the application must check for a free buffer before rendering.

If a surface doesn't have a free buffer, the application must return a buffer to the surface using release_buffer() and after that, the application can query for free buffers again.

Returns

true if the surface has free buffers, false otherwise

fn lock_front_buffer(&self) -> Option<BufferObject>

Lock rendering to the surface's current front buffer until it is released with release_ buffer()

This function must be called exactly once after calling eglSwapBuffers. Calling it before any eglSwapBuffer has happend on the surface or two or more times after eglSwapBuffers is an error. A new BufferObject representing the new front buffer is returned. On multiple invocations, all the returned BufferObjects must be released in order to release the actual surface buffer.

Returns

A buffer object that should be released with release_buffer() when no longer needed. If an error occurs this function returns None.

Example

// Render something

let buffer = surface.lock_front_buffer().unwrap();

// Output to the screen, etc.

surface.release_buffer(buffer);

fn release_buffer(&self, bo: BufferObject)

Release a locked buffer obtained lock_front_buffer()

Returns the underlying buffer to the Surface. Releasing a BufferObject will typically has_free_buffer() return true and thus allow rendering the next frame, but not always. The implementation may choose to destroy the BufferObject immediately or reuse it, in which case the user data associated with it is unchanged.

Arguments

bo: The BufferObject to be released

fn c_struct(&self) -> *const gbm_surface

Returns the gbm_surface for the Surface

Returns

A pointer to the gbm_surface used to create the Surface.

Trait Implementations

impl Drop for Surface

fn drop(&mut self)

A method called when the value goes out of scope.