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// Licensed under the Apache License, Version 2.0.
// This file may not be copied, modified, or distributed except according to those terms.
#![cfg(windows)]
#![allow(unused_variables)]
use glutin::ContextError;
use glutin::CreationError;
use glutin::GlAttributes;
use glutin::GlRequest;
use glutin::PixelFormat;
use glutin::PixelFormatRequirements;
use glutin::ReleaseBehavior;
use glutin::Robustness;
use glutin::Api;
use std::ffi::{CStr, CString};
use std::os::raw::c_int;
use std::ptr;
use std::cell::Cell;
use mozangle::egl::ffi as egl;
mod ffi {
pub use mozangle::egl::ffi as egl;
pub use mozangle::egl::ffi::*;
}
pub struct Context {
display: ffi::egl::types::EGLDisplay,
context: ffi::egl::types::EGLContext,
surface: Cell<ffi::egl::types::EGLSurface>,
api: Api,
pixel_format: PixelFormat,
}
impl Context {
/// Start building an EGL context.
///
/// This function initializes some things and chooses the pixel format.
///
/// To finish the process, you must call `.finish(window)` on the `ContextPrototype`.
pub fn new<'a>(
pf_reqs: &PixelFormatRequirements,
opengl: &'a GlAttributes<&'a Context>,
) -> Result<ContextPrototype<'a>, CreationError>
{
if opengl.sharing.is_some() {
unimplemented!()
}
// calling `eglGetDisplay` or equivalent
let display = unsafe { egl::GetDisplay(ptr::null_mut()) };
if display.is_null() {
return Err(CreationError::PlatformSpecific("Could not create EGL display object".to_string()));
}
let egl_version = unsafe {
let mut major: ffi::egl::types::EGLint = 0; // out param
let mut minor: ffi::egl::types::EGLint = 0; // out param
if egl::Initialize(display, &mut major, &mut minor) == 0 {
return Err(CreationError::OsError(format!("eglInitialize failed")))
}
(major, minor)
};
// the list of extensions supported by the client once initialized is different from the
// list of extensions obtained earlier
let extensions = if egl_version >= (1, 2) {
let p = unsafe { CStr::from_ptr(egl::QueryString(display, ffi::egl::EXTENSIONS as i32)) };
let list = String::from_utf8(p.to_bytes().to_vec()).unwrap_or_else(|_| format!(""));
list.split(' ').map(|e| e.to_string()).collect::<Vec<_>>()
} else {
vec![]
};
// binding the right API and choosing the version
let (version, api) = unsafe {
match opengl.version {
GlRequest::Latest => {
if egl_version >= (1, 4) {
if egl::BindAPI(ffi::egl::OPENGL_API) != 0 {
(None, Api::OpenGl)
} else if egl::BindAPI(ffi::egl::OPENGL_ES_API) != 0 {
(None, Api::OpenGlEs)
} else {
return Err(CreationError::OpenGlVersionNotSupported);
}
} else {
(None, Api::OpenGlEs)
}
},
GlRequest::Specific(Api::OpenGlEs, version) => {
if egl_version >= (1, 2) {
if egl::BindAPI(ffi::egl::OPENGL_ES_API) == 0 {
return Err(CreationError::OpenGlVersionNotSupported);
}
}
(Some(version), Api::OpenGlEs)
},
GlRequest::Specific(Api::OpenGl, version) => {
if egl_version < (1, 4) {
return Err(CreationError::OpenGlVersionNotSupported);
}
if egl::BindAPI(ffi::egl::OPENGL_API) == 0 {
return Err(CreationError::OpenGlVersionNotSupported);
}
(Some(version), Api::OpenGl)
},
GlRequest::Specific(_, _) => return Err(CreationError::OpenGlVersionNotSupported),
GlRequest::GlThenGles { opengles_version, opengl_version } => {
if egl_version >= (1, 4) {
if egl::BindAPI(ffi::egl::OPENGL_API) != 0 {
(Some(opengl_version), Api::OpenGl)
} else if egl::BindAPI(ffi::egl::OPENGL_ES_API) != 0 {
(Some(opengles_version), Api::OpenGlEs)
} else {
return Err(CreationError::OpenGlVersionNotSupported);
}
} else {
(Some(opengles_version), Api::OpenGlEs)
}
},
}
};
let (config_id, pixel_format) = unsafe {
choose_fbconfig(display, &egl_version, api, version, pf_reqs)?
};
Ok(ContextPrototype {
opengl: opengl,
display: display,
egl_version: egl_version,
extensions: extensions,
api: api,
version: version,
config_id: config_id,
pixel_format: pixel_format,
})
}
#[inline]
pub fn swap_buffers(&self) -> Result<(), ContextError> {
if self.surface.get() == ffi::egl::NO_SURFACE {
return Err(ContextError::ContextLost);
}
let ret = unsafe {
egl::SwapBuffers(self.display, self.surface.get())
};
if ret == 0 {
match unsafe { egl::GetError() } as u32 {
ffi::egl::CONTEXT_LOST => return Err(ContextError::ContextLost),
err => panic!("eglSwapBuffers failed (eglGetError returned 0x{:x})", err)
}
} else {
Ok(())
}
}
pub unsafe fn make_current(&self) -> Result<(), ContextError> {
let ret = egl::MakeCurrent(self.display, self.surface.get(), self.surface.get(), self.context);
if ret == 0 {
match egl::GetError() as u32 {
ffi::egl::CONTEXT_LOST => return Err(ContextError::ContextLost),
err => panic!("eglMakeCurrent failed (eglGetError returned 0x{:x})", err)
}
} else {
Ok(())
}
}
#[inline]
pub fn is_current(&self) -> bool {
unsafe { egl::GetCurrentContext() == self.context }
}
pub fn get_proc_address(&self, addr: &str) -> *const () {
let addr = CString::new(addr.as_bytes()).unwrap();
let addr = addr.as_ptr();
unsafe {
egl::GetProcAddress(addr) as *const _
}
}
#[inline]
pub fn get_api(&self) -> Api {
self.api
}
#[inline]
pub fn get_pixel_format(&self) -> PixelFormat {
self.pixel_format.clone()
}
}
unsafe impl Send for Context {}
unsafe impl Sync for Context {}
impl Drop for Context {
fn drop(&mut self) {
unsafe {
// we don't call MakeCurrent(0, 0) because we are not sure that the context
// is still the current one
egl::DestroyContext(self.display, self.context);
egl::DestroySurface(self.display, self.surface.get());
egl::Terminate(self.display);
}
}
}
pub struct ContextPrototype<'a> {
opengl: &'a GlAttributes<&'a Context>,
display: ffi::egl::types::EGLDisplay,
egl_version: (ffi::egl::types::EGLint, ffi::egl::types::EGLint),
extensions: Vec<String>,
api: Api,
version: Option<(u8, u8)>,
config_id: ffi::egl::types::EGLConfig,
pixel_format: PixelFormat,
}
impl<'a> ContextPrototype<'a> {
pub fn get_native_visual_id(&self) -> ffi::egl::types::EGLint {
let mut value = 0;
let ret = unsafe { egl::GetConfigAttrib(self.display, self.config_id,
ffi::egl::NATIVE_VISUAL_ID
as ffi::egl::types::EGLint, &mut value) };
if ret == 0 { panic!("eglGetConfigAttrib failed") };
value
}
pub fn finish(self, native_window: ffi::EGLNativeWindowType)
-> Result<Context, CreationError>
{
let surface = unsafe {
let surface = egl::CreateWindowSurface(self.display, self.config_id, native_window,
ptr::null());
if surface.is_null() {
return Err(CreationError::OsError(format!("eglCreateWindowSurface failed")))
}
surface
};
self.finish_impl(surface)
}
pub fn finish_pbuffer(self, dimensions: (u32, u32)) -> Result<Context, CreationError> {
let attrs = &[
ffi::egl::WIDTH as c_int, dimensions.0 as c_int,
ffi::egl::HEIGHT as c_int, dimensions.1 as c_int,
ffi::egl::NONE as c_int,
];
let surface = unsafe {
let surface = egl::CreatePbufferSurface(self.display, self.config_id,
attrs.as_ptr());
if surface.is_null() {
return Err(CreationError::OsError(format!("eglCreatePbufferSurface failed")))
}
surface
};
self.finish_impl(surface)
}
fn finish_impl(self, surface: ffi::egl::types::EGLSurface)
-> Result<Context, CreationError>
{
let context = unsafe {
if let Some(version) = self.version {
create_context(self.display, &self.egl_version,
&self.extensions, self.api, version, self.config_id,
self.opengl.debug, self.opengl.robustness)?
} else if self.api == Api::OpenGlEs {
if let Ok(ctxt) = create_context(self.display, &self.egl_version,
&self.extensions, self.api, (2, 0), self.config_id,
self.opengl.debug, self.opengl.robustness)
{
ctxt
} else if let Ok(ctxt) = create_context(self.display, &self.egl_version,
&self.extensions, self.api, (1, 0),
self.config_id, self.opengl.debug,
self.opengl.robustness)
{
ctxt
} else {
return Err(CreationError::OpenGlVersionNotSupported);
}
} else {
if let Ok(ctxt) = create_context(self.display, &self.egl_version,
&self.extensions, self.api, (3, 2), self.config_id,
self.opengl.debug, self.opengl.robustness)
{
ctxt
} else if let Ok(ctxt) = create_context(self.display, &self.egl_version,
&self.extensions, self.api, (3, 1),
self.config_id, self.opengl.debug,
self.opengl.robustness)
{
ctxt
} else if let Ok(ctxt) = create_context(self.display, &self.egl_version,
&self.extensions, self.api, (1, 0),
self.config_id, self.opengl.debug,
self.opengl.robustness)
{
ctxt
} else {
return Err(CreationError::OpenGlVersionNotSupported);
}
}
};
Ok(Context {
display: self.display,
context: context,
surface: Cell::new(surface),
api: self.api,
pixel_format: self.pixel_format,
})
}
}
unsafe fn choose_fbconfig(display: ffi::egl::types::EGLDisplay,
egl_version: &(ffi::egl::types::EGLint, ffi::egl::types::EGLint),
api: Api, version: Option<(u8, u8)>, reqs: &PixelFormatRequirements)
-> Result<(ffi::egl::types::EGLConfig, PixelFormat), CreationError>
{
let descriptor = {
let mut out: Vec<c_int> = Vec::with_capacity(37);
if egl_version >= &(1, 2) {
out.push(ffi::egl::COLOR_BUFFER_TYPE as c_int);
out.push(ffi::egl::RGB_BUFFER as c_int);
}
out.push(ffi::egl::SURFACE_TYPE as c_int);
// TODO: Some versions of Mesa report a BAD_ATTRIBUTE error
// if we ask for PBUFFER_BIT as well as WINDOW_BIT
out.push((ffi::egl::WINDOW_BIT) as c_int);
match (api, version) {
(Api::OpenGlEs, Some((3, _))) => {
if egl_version < &(1, 3) { return Err(CreationError::NoAvailablePixelFormat); }
out.push(ffi::egl::RENDERABLE_TYPE as c_int);
out.push(ffi::egl::OPENGL_ES3_BIT as c_int);
out.push(ffi::egl::CONFORMANT as c_int);
out.push(ffi::egl::OPENGL_ES3_BIT as c_int);
},
(Api::OpenGlEs, Some((2, _))) => {
if egl_version < &(1, 3) { return Err(CreationError::NoAvailablePixelFormat); }
out.push(ffi::egl::RENDERABLE_TYPE as c_int);
out.push(ffi::egl::OPENGL_ES2_BIT as c_int);
out.push(ffi::egl::CONFORMANT as c_int);
out.push(ffi::egl::OPENGL_ES2_BIT as c_int);
},
(Api::OpenGlEs, Some((1, _))) => {
if egl_version >= &(1, 3) {
out.push(ffi::egl::RENDERABLE_TYPE as c_int);
out.push(ffi::egl::OPENGL_ES_BIT as c_int);
out.push(ffi::egl::CONFORMANT as c_int);
out.push(ffi::egl::OPENGL_ES_BIT as c_int);
}
},
(Api::OpenGlEs, _) => unimplemented!(),
(Api::OpenGl, _) => {
if egl_version < &(1, 3) { return Err(CreationError::NoAvailablePixelFormat); }
out.push(ffi::egl::RENDERABLE_TYPE as c_int);
out.push(ffi::egl::OPENGL_BIT as c_int);
out.push(ffi::egl::CONFORMANT as c_int);
out.push(ffi::egl::OPENGL_BIT as c_int);
},
(_, _) => unimplemented!(),
};
if let Some(hardware_accelerated) = reqs.hardware_accelerated {
out.push(ffi::egl::CONFIG_CAVEAT as c_int);
out.push(if hardware_accelerated {
ffi::egl::NONE as c_int
} else {
ffi::egl::SLOW_CONFIG as c_int
});
}
if let Some(color) = reqs.color_bits {
out.push(ffi::egl::RED_SIZE as c_int);
out.push((color / 3) as c_int);
out.push(ffi::egl::GREEN_SIZE as c_int);
out.push((color / 3 + if color % 3 != 0 { 1 } else { 0 }) as c_int);
out.push(ffi::egl::BLUE_SIZE as c_int);
out.push((color / 3 + if color % 3 == 2 { 1 } else { 0 }) as c_int);
}
if let Some(alpha) = reqs.alpha_bits {
out.push(ffi::egl::ALPHA_SIZE as c_int);
out.push(alpha as c_int);
}
if let Some(depth) = reqs.depth_bits {
out.push(ffi::egl::DEPTH_SIZE as c_int);
out.push(depth as c_int);
}
if let Some(stencil) = reqs.stencil_bits {
out.push(ffi::egl::STENCIL_SIZE as c_int);
out.push(stencil as c_int);
}
if let Some(true) = reqs.double_buffer {
return Err(CreationError::NoAvailablePixelFormat);
}
if let Some(multisampling) = reqs.multisampling {
out.push(ffi::egl::SAMPLES as c_int);
out.push(multisampling as c_int);
}
if reqs.stereoscopy {
return Err(CreationError::NoAvailablePixelFormat);
}
// FIXME: srgb is not taken into account
match reqs.release_behavior {
ReleaseBehavior::Flush => (),
ReleaseBehavior::None => {
// TODO: with EGL you need to manually set the behavior
unimplemented!()
},
}
out.push(ffi::egl::NONE as c_int);
out
};
// calling `eglChooseConfig`
let mut config_id = ptr::null(); // out param
let mut num_configs = 0; // out param
if egl::ChooseConfig(display, descriptor.as_ptr(), &mut config_id, 1, &mut num_configs) == 0 {
return Err(CreationError::OsError(format!("eglChooseConfig failed")));
}
if num_configs == 0 {
return Err(CreationError::NoAvailablePixelFormat);
}
// analyzing each config
macro_rules! attrib {
($display:expr, $config:expr, $attr:expr) => (
{
let mut value = 0; // out param
let res = egl::GetConfigAttrib($display, $config,
$attr as ffi::egl::types::EGLint, &mut value);
if res == 0 {
return Err(CreationError::OsError(format!("eglGetConfigAttrib failed")));
}
value
}
)
}
let desc = PixelFormat {
hardware_accelerated: attrib!(display, config_id, ffi::egl::CONFIG_CAVEAT)
!= ffi::egl::SLOW_CONFIG as i32,
color_bits: attrib!(display, config_id, ffi::egl::RED_SIZE) as u8 +
attrib!(display, config_id, ffi::egl::BLUE_SIZE) as u8 +
attrib!(display, config_id, ffi::egl::GREEN_SIZE) as u8,
alpha_bits: attrib!(display, config_id, ffi::egl::ALPHA_SIZE) as u8,
depth_bits: attrib!(display, config_id, ffi::egl::DEPTH_SIZE) as u8,
stencil_bits: attrib!(display, config_id, ffi::egl::STENCIL_SIZE) as u8,
stereoscopy: false,
double_buffer: true,
multisampling: match attrib!(display, config_id, ffi::egl::SAMPLES) {
0 | 1 => None,
a => Some(a as u16),
},
srgb: false, // TODO: use EGL_KHR_gl_colorspace to know that
};
Ok((config_id, desc))
}
unsafe fn create_context(display: ffi::egl::types::EGLDisplay,
egl_version: &(ffi::egl::types::EGLint, ffi::egl::types::EGLint),
extensions: &[String], api: Api, version: (u8, u8),
config_id: ffi::egl::types::EGLConfig, gl_debug: bool,
gl_robustness: Robustness)
-> Result<ffi::egl::types::EGLContext, CreationError>
{
let mut context_attributes = Vec::with_capacity(10);
let mut flags = 0;
if egl_version >= &(1, 5) || extensions.iter().find(|s| s == &"EGL_KHR_create_context")
.is_some()
{
context_attributes.push(ffi::egl::CONTEXT_MAJOR_VERSION as i32);
context_attributes.push(version.0 as i32);
context_attributes.push(ffi::egl::CONTEXT_MINOR_VERSION as i32);
context_attributes.push(version.1 as i32);
// handling robustness
let supports_robustness = egl_version >= &(1, 5) ||
extensions.iter()
.find(|s| s == &"EGL_EXT_create_context_robustness")
.is_some();
match gl_robustness {
Robustness::NotRobust => (),
Robustness::NoError => {
if extensions.iter().find(|s| s == &"EGL_KHR_create_context_no_error").is_some() {
context_attributes.push(ffi::egl::CONTEXT_OPENGL_NO_ERROR_KHR as c_int);
context_attributes.push(1);
}
},
Robustness::RobustNoResetNotification => {
if supports_robustness {
context_attributes.push(ffi::egl::CONTEXT_OPENGL_RESET_NOTIFICATION_STRATEGY
as c_int);
context_attributes.push(ffi::egl::NO_RESET_NOTIFICATION as c_int);
flags = flags | ffi::egl::CONTEXT_OPENGL_ROBUST_ACCESS as c_int;
} else {
return Err(CreationError::RobustnessNotSupported);
}
},
Robustness::TryRobustNoResetNotification => {
if supports_robustness {
context_attributes.push(ffi::egl::CONTEXT_OPENGL_RESET_NOTIFICATION_STRATEGY
as c_int);
context_attributes.push(ffi::egl::NO_RESET_NOTIFICATION as c_int);
flags = flags | ffi::egl::CONTEXT_OPENGL_ROBUST_ACCESS as c_int;
}
},
Robustness::RobustLoseContextOnReset => {
if supports_robustness {
context_attributes.push(ffi::egl::CONTEXT_OPENGL_RESET_NOTIFICATION_STRATEGY
as c_int);
context_attributes.push(ffi::egl::LOSE_CONTEXT_ON_RESET as c_int);
flags = flags | ffi::egl::CONTEXT_OPENGL_ROBUST_ACCESS as c_int;
} else {
return Err(CreationError::RobustnessNotSupported);
}
},
Robustness::TryRobustLoseContextOnReset => {
if supports_robustness {
context_attributes.push(ffi::egl::CONTEXT_OPENGL_RESET_NOTIFICATION_STRATEGY
as c_int);
context_attributes.push(ffi::egl::LOSE_CONTEXT_ON_RESET as c_int);
flags = flags | ffi::egl::CONTEXT_OPENGL_ROBUST_ACCESS as c_int;
}
},
}
if gl_debug {
if egl_version >= &(1, 5) {
context_attributes.push(ffi::egl::CONTEXT_OPENGL_DEBUG as i32);
context_attributes.push(ffi::egl::TRUE as i32);
}
// TODO: using this flag sometimes generates an error
// there was a change in the specs that added this flag, so it may not be
// supported everywhere ; however it is not possible to know whether it is
// supported or not
//flags = flags | ffi::egl::CONTEXT_OPENGL_DEBUG_BIT_KHR as i32;
}
context_attributes.push(ffi::egl::CONTEXT_FLAGS_KHR as i32);
context_attributes.push(flags);
} else if egl_version >= &(1, 3) && api == Api::OpenGlEs {
// robustness is not supported
match gl_robustness {
Robustness::RobustNoResetNotification | Robustness::RobustLoseContextOnReset => {
return Err(CreationError::RobustnessNotSupported);
},
_ => ()
}
context_attributes.push(ffi::egl::CONTEXT_CLIENT_VERSION as i32);
context_attributes.push(version.0 as i32);
}
context_attributes.push(ffi::egl::NONE as i32);
let context = egl::CreateContext(display, config_id, ptr::null(),
context_attributes.as_ptr());
if context.is_null() {
match egl::GetError() as u32 {
ffi::egl::BAD_ATTRIBUTE => return Err(CreationError::OpenGlVersionNotSupported),
e => panic!("eglCreateContext failed: 0x{:x}", e),
}
}
Ok(context)
}