pub struct Context { /* private fields */ }Expand description
Stores the state and information required for glium to execute commands. Most public glium
functions require passing a Rc<Context>.
Implementations§
source§impl Context
impl Context
sourcepub unsafe fn new<B, E>(
backend: B,
check_current_context: bool,
callback_behavior: DebugCallbackBehavior
) -> Result<Rc<Context>, GliumCreationError<E>>where
B: Backend + 'static,
pub unsafe fn new<B, E>( backend: B, check_current_context: bool, callback_behavior: DebugCallbackBehavior ) -> Result<Rc<Context>, GliumCreationError<E>>where B: Backend + 'static,
Builds a new context.
The check_current_context parameter tells the context whether it should check
if the backend’s OpenGL context is the current one before each OpenGL operation.
If you pass false, you must ensure that no other OpenGL context is going to be made
current in the same thread as this context. Passing true makes things safe but
is slightly slower.
The OpenGL context must be newly-created. If you make modifications to the context before passing it to this function, glium’s state cache may mismatch the actual one.
sourcepub fn get_framebuffer_dimensions(&self) -> (u32, u32)
pub fn get_framebuffer_dimensions(&self) -> (u32, u32)
Calls get_framebuffer_dimensions on the backend object stored by this context.
sourcepub unsafe fn rebuild<B, E>(
&self,
new_backend: B
) -> Result<(), GliumCreationError<E>>where
B: Backend + 'static,
pub unsafe fn rebuild<B, E>( &self, new_backend: B ) -> Result<(), GliumCreationError<E>>where B: Backend + 'static,
Changes the OpenGL context associated with this context.
The new context must have lists shared with the old one.
sourcepub fn swap_buffers(&self) -> Result<(), SwapBuffersError>
pub fn swap_buffers(&self) -> Result<(), SwapBuffersError>
Swaps the buffers in the backend.
sourcepub fn get_version(&self) -> &Version
pub fn get_version(&self) -> &Version
DEPRECATED. Use get_opengl_version instead.
sourcepub fn get_opengl_version(&self) -> &Version
pub fn get_opengl_version(&self) -> &Version
Returns the OpenGL version detected by this context.
sourcepub fn get_supported_glsl_version(&self) -> Version
pub fn get_supported_glsl_version(&self) -> Version
Returns the GLSL version guaranteed to be supported.
sourcepub fn is_glsl_version_supported(&self, version: &Version) -> bool
pub fn is_glsl_version_supported(&self, version: &Version) -> bool
Returns true if the given GLSL version is supported.
sourcepub fn get_opengl_version_string(&self) -> &str
pub fn get_opengl_version_string(&self) -> &str
Returns a string containing this GL version or release number used by this context.
Vendor-specific information may follow the version number.
sourcepub fn get_opengl_vendor_string(&self) -> &str
pub fn get_opengl_vendor_string(&self) -> &str
Returns a string containing the company responsible for this GL implementation.
sourcepub fn get_opengl_renderer_string(&self) -> &str
pub fn get_opengl_renderer_string(&self) -> &str
Returns a string containing the name of the GL renderer used by this context.
This name is typically specific to a particular configuration of a hardware platform.
sourcepub fn is_debug(&self) -> bool
pub fn is_debug(&self) -> bool
Returns true if the context is in debug mode.
Debug mode may provide additional error and performance issue reporting functionality.
sourcepub fn is_forward_compatible(&self) -> bool
pub fn is_forward_compatible(&self) -> bool
Returns true if the context is in “forward-compatible” mode.
Forward-compatible mode means that no deprecated functionality will be supported.
sourcepub fn get_opengl_profile(&self) -> Option<Profile>
pub fn get_opengl_profile(&self) -> Option<Profile>
Returns this context’s OpenGL profile if available.
The context profile is available from OpenGL 3.2 onwards. Returns None if not supported.
sourcepub fn is_robust(&self) -> bool
pub fn is_robust(&self) -> bool
Returns true if out-of-bound buffer access from the GPU side (inside a program) cannot result in a crash.
You should take extra care if is_robust returns false.
sourcepub fn is_context_loss_possible(&self) -> bool
pub fn is_context_loss_possible(&self) -> bool
Returns true if a context loss is possible.
sourcepub fn is_context_lost(&self) -> bool
pub fn is_context_lost(&self) -> bool
Returns true if the context has been lost and needs to be recreated.
Implementation
If it has been determined that the context has been lost before, then the function
immediatly returns true. Otherwise, calls glGetGraphicsResetStatus. If this function
is not available, returns false.
sourcepub fn get_release_behavior(&self) -> ReleaseBehavior
pub fn get_release_behavior(&self) -> ReleaseBehavior
Returns the behavior when the current OpenGL context is changed.
The most common value is Flush. In order to get None you must explicitely request it
during creation.
sourcepub fn get_max_anisotropy_support(&self) -> Option<u16>
pub fn get_max_anisotropy_support(&self) -> Option<u16>
Returns the maximum value that can be used for anisotropic filtering, or None
if the hardware doesn’t support it.
sourcepub fn get_max_viewport_dimensions(&self) -> (u32, u32)
pub fn get_max_viewport_dimensions(&self) -> (u32, u32)
Returns the maximum dimensions of the viewport.
Glium will panic if you request a larger viewport than this when drawing.
sourcepub fn release_shader_compiler(&self)
pub fn release_shader_compiler(&self)
Releases the shader compiler, indicating that no new programs will be created for a while.
This method is a no-op if it’s not available in the implementation.
sourcepub fn get_free_video_memory(&self) -> Option<usize>
pub fn get_free_video_memory(&self) -> Option<usize>
Returns an estimate of the amount of video memory available in bytes.
Returns None if no estimate is available.
sourcepub fn read_front_buffer<T>(&self) -> Twhere
T: Texture2dDataSink<(u8, u8, u8, u8)>,
pub fn read_front_buffer<T>(&self) -> Twhere T: Texture2dDataSink<(u8, u8, u8, u8)>,
Reads the content of the front buffer.
You will only see the data that has finished being drawn.
This function can return any type that implements Texture2dDataSink<(u8, u8, u8, u8)>.
Example
let pixels: Vec<Vec<(u8, u8, u8, u8)>> = display.read_front_buffer();sourcepub unsafe fn exec_in_context<'a, T, F>(&self, action: F) -> Twhere
T: Send + 'static,
F: FnOnce() -> T + 'a,
pub unsafe fn exec_in_context<'a, T, F>(&self, action: F) -> Twhere T: Send + 'static, F: FnOnce() -> T + 'a,
Execute an arbitrary closure with the OpenGL context active. Useful if another component needs to directly manipulate OpenGL state.
If action manipulates any OpenGL state, it must be restored before action
completes.
sourcepub fn assert_no_error(&self, user_msg: Option<&str>)
pub fn assert_no_error(&self, user_msg: Option<&str>)
Asserts that there are no OpenGL errors pending.
This function should be used in tests.
sourcepub fn synchronize(&self)
pub fn synchronize(&self)
DEPRECATED. Renamed finish.
sourcepub fn finish(&self)
pub fn finish(&self)
Calls glFinish(). This waits until all the previously issued commands have finished
being executed.
When you execute OpenGL functions, they are not executed immediately. Instead they are put in a queue. This function flushes this queue, then waits until all commands have finished being executed.
You normally don’t need to call this function manually, except for debugging purposes.
sourcepub fn flush(&self)
pub fn flush(&self)
Calls glFlush(). This starts executing the commands that you have issued if it is not
yet the case.
When you execute OpenGL functions, they are not executed immediately. Instead they are put in a queue. This function flushes this queue so that commands start being executed.
You normally don’t need to call this function manually. Swapping buffers automatically flushes the queue. This function can be useful if you want to benchmark the time it takes from your OpenGL driver to process commands.
sourcepub fn insert_debug_marker(&self, marker: &str) -> Result<(), ()>
pub fn insert_debug_marker(&self, marker: &str) -> Result<(), ()>
Inserts a debugging string in the commands queue. If you use an OpenGL debugger, you will be able to see that string.
This is helpful to understand where you are when you have big applications.
Returns Err if the backend doesn’t support this functionnality. You can choose whether
to call .unwrap() if you want to make sure that it works, or .ok() if you don’t care.