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// surfman/src/platform/windows/wgl/surface.rs
//
//! An implementation of the GPU device for Windows using WGL/Direct3D interoperability.
use super::context::{self, Context, WGL_EXTENSION_FUNCTIONS};
use super::device::Device;
use crate::error::WindowingApiError;
use crate::renderbuffers::Renderbuffers;
use crate::{ContextID, Error, SurfaceAccess, SurfaceID, SurfaceInfo, SurfaceType};
use crate::gl;
use crate::gl::types::{GLenum, GLint, GLuint};
use crate::gl_utils;
use euclid::default::Size2D;
use std::fmt::{self, Debug, Formatter};
use std::marker::PhantomData;
use std::mem;
use std::os::raw::c_void;
use std::ptr;
use std::thread;
use winapi::shared::dxgi::IDXGIResource;
use winapi::shared::dxgiformat::DXGI_FORMAT_R8G8B8A8_UNORM;
use winapi::shared::dxgitype::DXGI_SAMPLE_DESC;
use winapi::shared::minwindef::{FALSE, UINT};
use winapi::shared::ntdef::HANDLE;
use winapi::shared::windef::HWND;
use winapi::shared::winerror;
use winapi::um::d3d11::{ID3D11Texture2D, D3D11_USAGE_DEFAULT};
use winapi::um::d3d11::{D3D11_BIND_RENDER_TARGET, D3D11_BIND_SHADER_RESOURCE};
use winapi::um::d3d11::{D3D11_RESOURCE_MISC_SHARED_KEYEDMUTEX, D3D11_TEXTURE2D_DESC};
use winapi::um::handleapi::INVALID_HANDLE_VALUE;
use winapi::um::wingdi;
use winapi::um::winuser;
use winapi::Interface;
use wio::com::ComPtr;
const SURFACE_GL_TEXTURE_TARGET: GLenum = gl::TEXTURE_2D;
const WGL_ACCESS_READ_ONLY_NV: GLenum = 0x0000;
const WGL_ACCESS_READ_WRITE_NV: GLenum = 0x0001;
/// Represents a hardware buffer of pixels that can be rendered to via the CPU or GPU and either
/// displayed in a native widget or bound to a texture for reading.
///
/// Surfaces come in two varieties: generic and widget surfaces. Generic surfaces can be bound to a
/// texture but cannot be displayed in a widget (without using other APIs such as Core Animation,
/// DirectComposition, or XPRESENT). Widget surfaces are the opposite: they can be displayed in a
/// widget but not bound to a texture.
///
/// Surfaces are specific to a given context and cannot be rendered to from any context other than
/// the one they were created with. However, they can be *read* from any context on any thread (as
/// long as that context shares the same adapter and connection), by wrapping them in a
/// `SurfaceTexture`.
///
/// Depending on the platform, each surface may be internally double-buffered.
///
/// Surfaces must be destroyed with the `destroy_surface()` method, or a panic will occur.
pub struct Surface {
pub(crate) size: Size2D<i32>,
pub(crate) context_id: ContextID,
pub(crate) win32_objects: Win32Objects,
pub(crate) destroyed: bool,
}
pub(crate) enum Win32Objects {
Texture {
d3d11_texture: ComPtr<ID3D11Texture2D>,
dxgi_share_handle: HANDLE,
gl_dx_interop_object: HANDLE,
gl_texture: GLuint,
gl_framebuffer: GLuint,
renderbuffers: Renderbuffers,
},
Widget {
window_handle: HWND,
},
}
/// Represents an OpenGL texture that wraps a surface.
///
/// Reading from the associated OpenGL texture reads from the surface. It is undefined behavior to
/// write to such a texture (e.g. by binding it to a framebuffer and rendering to that
/// framebuffer).
///
/// Surface textures are local to a context, but that context does not have to be the same context
/// as that associated with the underlying surface. The texture must be destroyed with the
/// `destroy_surface_texture()` method, or a panic will occur.
pub struct SurfaceTexture {
pub(crate) surface: Surface,
#[allow(dead_code)]
pub(crate) local_d3d11_texture: ComPtr<ID3D11Texture2D>,
local_gl_dx_interop_object: HANDLE,
pub(crate) gl_texture: GLuint,
pub(crate) phantom: PhantomData<*const ()>,
}
unsafe impl Send for Surface {}
impl Debug for Surface {
fn fmt(&self, f: &mut Formatter) -> Result<(), fmt::Error> {
write!(f, "Surface({:x})", self.id().0)
}
}
impl Drop for Surface {
fn drop(&mut self) {
if !self.destroyed && !thread::panicking() {
panic!("Should have destroyed the surface first with `destroy_surface()`!")
}
}
}
impl Debug for SurfaceTexture {
fn fmt(&self, f: &mut Formatter) -> Result<(), fmt::Error> {
write!(f, "SurfaceTexture({:?})", self.surface)
}
}
/// Wraps a Windows `HWND` window handle.
pub struct NativeWidget {
/// A window handle.
///
/// This can be a top-level window or a control.
pub window_handle: HWND,
}
impl Device {
/// Creates either a generic or a widget surface, depending on the supplied surface type.
///
/// Only the given context may ever render to the surface, but generic surfaces can be wrapped
/// up in a `SurfaceTexture` for reading by other contexts.
pub fn create_surface(
&mut self,
context: &Context,
_: SurfaceAccess,
surface_type: SurfaceType<NativeWidget>,
) -> Result<Surface, Error> {
match surface_type {
SurfaceType::Generic { size } => self.create_generic_surface(context, &size),
SurfaceType::Widget { native_widget } => {
self.create_widget_surface(context, native_widget)
}
}
}
fn create_generic_surface(
&mut self,
context: &Context,
size: &Size2D<i32>,
) -> Result<Surface, Error> {
let dx_interop_functions = match WGL_EXTENSION_FUNCTIONS.dx_interop_functions {
None => return Err(Error::RequiredExtensionUnavailable),
Some(ref dx_interop_functions) => dx_interop_functions,
};
unsafe {
let _guard = self.temporarily_make_context_current(context)?;
// Create the Direct3D 11 texture.
let d3d11_texture2d_desc = D3D11_TEXTURE2D_DESC {
Width: size.width as UINT,
Height: size.height as UINT,
MipLevels: 1,
ArraySize: 1,
Format: DXGI_FORMAT_R8G8B8A8_UNORM,
SampleDesc: DXGI_SAMPLE_DESC {
Count: 1,
Quality: 0,
},
Usage: D3D11_USAGE_DEFAULT,
BindFlags: D3D11_BIND_SHADER_RESOURCE | D3D11_BIND_RENDER_TARGET,
CPUAccessFlags: 0,
MiscFlags: D3D11_RESOURCE_MISC_SHARED_KEYEDMUTEX,
};
let mut d3d11_texture = ptr::null_mut();
let mut result = self.d3d11_device.CreateTexture2D(
&d3d11_texture2d_desc,
ptr::null(),
&mut d3d11_texture,
);
if !winerror::SUCCEEDED(result) {
return Err(Error::SurfaceCreationFailed(WindowingApiError::Failed));
}
assert!(!d3d11_texture.is_null());
let d3d11_texture = ComPtr::from_raw(d3d11_texture);
// Upcast it to a DXGI resource.
let mut dxgi_resource: *mut IDXGIResource = ptr::null_mut();
result = d3d11_texture.QueryInterface(
&IDXGIResource::uuidof(),
&mut dxgi_resource as *mut *mut IDXGIResource as *mut *mut c_void,
);
assert!(winerror::SUCCEEDED(result));
assert!(!dxgi_resource.is_null());
let dxgi_resource = ComPtr::from_raw(dxgi_resource);
// Get the share handle. We'll need it both to bind to GL and to share the texture
// across contexts.
let mut dxgi_share_handle = INVALID_HANDLE_VALUE;
result = dxgi_resource.GetSharedHandle(&mut dxgi_share_handle);
assert!(winerror::SUCCEEDED(result));
assert_ne!(dxgi_share_handle, INVALID_HANDLE_VALUE);
// Tell GL about the share handle.
let ok = (dx_interop_functions.DXSetResourceShareHandleNV)(
d3d11_texture.as_raw() as *mut c_void,
dxgi_share_handle,
);
assert_ne!(ok, FALSE);
// Make our texture object on the GL side.
let mut gl_texture = 0;
context.gl.GenTextures(1, &mut gl_texture);
// Bind the GL texture to the D3D11 texture.
let gl_dx_interop_object = (dx_interop_functions.DXRegisterObjectNV)(
self.gl_dx_interop_device,
d3d11_texture.as_raw() as *mut c_void,
gl_texture,
gl::TEXTURE_2D,
WGL_ACCESS_READ_WRITE_NV,
);
// Per the spec, and unlike other HANDLEs, null indicates an error.
if gl_dx_interop_object.is_null() {
let msg = std::io::Error::last_os_error(); // Equivalent to GetLastError().
error!(
"Unable to share surface between OpenGL and DirectX. OS error '{}'.",
msg
);
return Err(Error::SurfaceCreationFailed(WindowingApiError::Failed));
}
// Build our FBO.
let mut gl_framebuffer = 0;
context.gl.GenFramebuffers(1, &mut gl_framebuffer);
let _guard = self.temporarily_bind_framebuffer(context, gl_framebuffer);
// Attach the reflected D3D11 texture to that FBO.
context.gl.FramebufferTexture2D(
gl::FRAMEBUFFER,
gl::COLOR_ATTACHMENT0,
SURFACE_GL_TEXTURE_TARGET,
gl_texture,
0,
);
// Create renderbuffers as appropriate, and attach them.
let context_descriptor = self.context_descriptor(context);
let context_attributes = self.context_descriptor_attributes(&context_descriptor);
let renderbuffers = Renderbuffers::new(&context.gl, &size, &context_attributes);
renderbuffers.bind_to_current_framebuffer(&context.gl);
// FIXME(pcwalton): Do we need to acquire the keyed mutex, or does the GL driver do
// that?
Ok(Surface {
size: *size,
context_id: context.id,
win32_objects: Win32Objects::Texture {
d3d11_texture,
dxgi_share_handle,
gl_dx_interop_object,
gl_texture,
gl_framebuffer,
renderbuffers,
},
destroyed: false,
})
}
}
fn create_widget_surface(
&mut self,
context: &Context,
native_widget: NativeWidget,
) -> Result<Surface, Error> {
unsafe {
// Get the bounds of the native HWND.
let mut widget_rect = mem::zeroed();
let ok = winuser::GetWindowRect(native_widget.window_handle, &mut widget_rect);
if ok == FALSE {
return Err(Error::InvalidNativeWidget);
}
// Set its pixel format.
{
let context_dc_guard = self.get_context_dc(context);
let pixel_format = wingdi::GetPixelFormat(context_dc_guard.dc);
let window_dc = winuser::GetDC(native_widget.window_handle);
context::set_dc_pixel_format(window_dc, pixel_format);
}
Ok(Surface {
size: Size2D::new(
widget_rect.right - widget_rect.left,
widget_rect.bottom - widget_rect.top,
),
context_id: context.id,
win32_objects: Win32Objects::Widget {
window_handle: native_widget.window_handle,
},
destroyed: false,
})
}
}
/// Destroys a surface.
///
/// The supplied context must be the context the surface is associated with, or this returns
/// an `IncompatibleSurface` error.
///
/// You must explicitly call this method to dispose of a surface. Otherwise, a panic occurs in
/// the `drop` method.
pub fn destroy_surface(
&self,
context: &mut Context,
surface: &mut Surface,
) -> Result<(), Error> {
let dx_interop_functions = WGL_EXTENSION_FUNCTIONS
.dx_interop_functions
.as_ref()
.expect("How did you make a surface without DX interop?");
if context.id != surface.context_id {
return Err(Error::IncompatibleSurface);
}
let _guard = self.temporarily_make_context_current(context)?;
unsafe {
match surface.win32_objects {
Win32Objects::Texture {
ref mut gl_dx_interop_object,
ref mut gl_texture,
ref mut gl_framebuffer,
ref mut renderbuffers,
d3d11_texture: _,
dxgi_share_handle: _,
} => {
renderbuffers.destroy(&context.gl);
gl_utils::destroy_framebuffer(&context.gl, *gl_framebuffer);
*gl_framebuffer = 0;
context.gl.DeleteTextures(1, gl_texture);
*gl_texture = 0;
let ok = (dx_interop_functions.DXUnregisterObjectNV)(
self.gl_dx_interop_device,
*gl_dx_interop_object,
);
assert_ne!(ok, FALSE);
*gl_dx_interop_object = INVALID_HANDLE_VALUE;
}
Win32Objects::Widget { window_handle: _ } => {}
}
surface.destroyed = true;
}
Ok(())
}
/// Creates a surface texture from an existing generic surface for use with the given context.
///
/// The surface texture is local to the supplied context and takes ownership of the surface.
/// Destroying the surface texture allows you to retrieve the surface again.
///
/// *The supplied context does not have to be the same context that the surface is associated
/// with.* This allows you to render to a surface in one context and sample from that surface
/// in another context.
///
/// Calling this method on a widget surface returns a `WidgetAttached` error.
pub fn create_surface_texture(
&self,
context: &mut Context,
surface: Surface,
) -> Result<SurfaceTexture, (Error, Surface)> {
let dxgi_share_handle = match surface.win32_objects {
Win32Objects::Widget { .. } => return Err((Error::WidgetAttached, surface)),
Win32Objects::Texture {
dxgi_share_handle, ..
} => dxgi_share_handle,
};
let dx_interop_functions = WGL_EXTENSION_FUNCTIONS
.dx_interop_functions
.as_ref()
.expect("How did you make a surface without DX interop?");
let _guard = match self.temporarily_make_context_current(context) {
Ok(guard) => guard,
Err(err) => return Err((err, surface)),
};
unsafe {
// Create a new texture wrapping the shared handle.
let mut local_d3d11_texture = ptr::null_mut();
let result = self.d3d11_device.OpenSharedResource(
dxgi_share_handle,
&ID3D11Texture2D::uuidof(),
&mut local_d3d11_texture,
);
if !winerror::SUCCEEDED(result) || local_d3d11_texture.is_null() {
return Err((
Error::SurfaceImportFailed(WindowingApiError::Failed),
surface,
));
}
let local_d3d11_texture = ComPtr::from_raw(local_d3d11_texture as *mut ID3D11Texture2D);
// Make GL aware of the connection between the share handle and the texture.
let ok = (dx_interop_functions.DXSetResourceShareHandleNV)(
local_d3d11_texture.as_raw() as *mut c_void,
dxgi_share_handle,
);
assert_ne!(ok, FALSE);
// Create a GL texture.
let mut gl_texture = 0;
context.gl.GenTextures(1, &mut gl_texture);
// Register that texture with GL/DX interop.
let mut local_gl_dx_interop_object = (dx_interop_functions.DXRegisterObjectNV)(
self.gl_dx_interop_device,
local_d3d11_texture.as_raw() as *mut c_void,
gl_texture,
gl::TEXTURE_2D,
WGL_ACCESS_READ_ONLY_NV,
);
// Lock the texture so that we can use it.
let ok = (dx_interop_functions.DXLockObjectsNV)(
self.gl_dx_interop_device,
1,
&mut local_gl_dx_interop_object,
);
assert_ne!(ok, FALSE);
// Initialize the texture, for convenience.
// FIXME(pcwalton): We should probably reset the bound texture after this.
context.gl.BindTexture(gl::TEXTURE_2D, gl_texture);
context
.gl
.TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MAG_FILTER, gl::LINEAR as GLint);
context
.gl
.TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MIN_FILTER, gl::LINEAR as GLint);
context.gl.TexParameteri(
gl::TEXTURE_2D,
gl::TEXTURE_WRAP_S,
gl::CLAMP_TO_EDGE as GLint,
);
context.gl.TexParameteri(
gl::TEXTURE_2D,
gl::TEXTURE_WRAP_T,
gl::CLAMP_TO_EDGE as GLint,
);
// Finish up.
Ok(SurfaceTexture {
surface,
local_d3d11_texture,
local_gl_dx_interop_object,
gl_texture,
phantom: PhantomData,
})
}
}
/// Destroys a surface texture and returns the underlying surface.
///
/// The supplied context must be the same context the surface texture was created with, or an
/// `IncompatibleSurfaceTexture` error is returned.
///
/// All surface textures must be explicitly destroyed with this function, or a panic will
/// occur.
pub fn destroy_surface_texture(
&self,
context: &mut Context,
mut surface_texture: SurfaceTexture,
) -> Result<Surface, (Error, SurfaceTexture)> {
let dx_interop_functions = WGL_EXTENSION_FUNCTIONS
.dx_interop_functions
.as_ref()
.expect("How did you make a surface without DX interop?");
let _guard = match self.temporarily_make_context_current(context) {
Ok(guard) => guard,
Err(err) => return Err((err, surface_texture)),
};
unsafe {
// Unlock the texture.
let ok = (dx_interop_functions.DXUnlockObjectsNV)(
self.gl_dx_interop_device,
1,
&mut surface_texture.local_gl_dx_interop_object,
);
assert_ne!(ok, FALSE);
// Unregister the texture from GL/DX interop.
let ok = (dx_interop_functions.DXUnregisterObjectNV)(
self.gl_dx_interop_device,
surface_texture.local_gl_dx_interop_object,
);
assert_ne!(ok, FALSE);
surface_texture.local_gl_dx_interop_object = INVALID_HANDLE_VALUE;
// Destroy the GL texture.
context.gl.DeleteTextures(1, &surface_texture.gl_texture);
surface_texture.gl_texture = 0;
}
Ok(surface_texture.surface)
}
pub(crate) fn lock_surface(&self, surface: &Surface) {
let mut gl_dx_interop_object = match surface.win32_objects {
Win32Objects::Widget { .. } => return,
Win32Objects::Texture {
gl_dx_interop_object,
..
} => gl_dx_interop_object,
};
let dx_interop_functions = WGL_EXTENSION_FUNCTIONS
.dx_interop_functions
.as_ref()
.expect("How did you make a surface without DX interop?");
unsafe {
let ok = (dx_interop_functions.DXLockObjectsNV)(
self.gl_dx_interop_device,
1,
&mut gl_dx_interop_object,
);
assert_ne!(ok, FALSE);
}
}
pub(crate) fn unlock_surface(&self, surface: &Surface) {
let mut gl_dx_interop_object = match surface.win32_objects {
Win32Objects::Widget { .. } => return,
Win32Objects::Texture {
gl_dx_interop_object,
..
} => gl_dx_interop_object,
};
let dx_interop_functions = WGL_EXTENSION_FUNCTIONS
.dx_interop_functions
.as_ref()
.expect("How did you make a surface without DX interop?");
unsafe {
let ok = (dx_interop_functions.DXUnlockObjectsNV)(
self.gl_dx_interop_device,
1,
&mut gl_dx_interop_object,
);
assert_ne!(ok, FALSE);
}
}
/// Returns a pointer to the underlying surface data for reading or writing by the CPU.
#[inline]
pub fn lock_surface_data<'s>(
&self,
_surface: &'s mut Surface,
) -> Result<SurfaceDataGuard<'s>, Error> {
Err(Error::Unimplemented)
}
/// Returns the OpenGL texture target needed to read from this surface texture.
///
/// This will be `GL_TEXTURE_2D` or `GL_TEXTURE_RECTANGLE`, depending on platform.
#[inline]
pub fn surface_gl_texture_target(&self) -> GLenum {
gl::TEXTURE_2D
}
/// Displays the contents of a widget surface on screen.
///
/// Widget surfaces are internally double-buffered, so changes to them don't show up in their
/// associated widgets until this method is called.
///
/// The supplied context must match the context the surface was created with, or an
/// `IncompatibleSurface` error is returned.
pub fn present_surface(&self, _: &Context, surface: &mut Surface) -> Result<(), Error> {
let window_handle = match surface.win32_objects {
Win32Objects::Widget { window_handle } => window_handle,
_ => return Err(Error::NoWidgetAttached),
};
unsafe {
let dc = winuser::GetDC(window_handle);
let ok = wingdi::SwapBuffers(dc);
assert_ne!(ok, FALSE);
winuser::ReleaseDC(window_handle, dc);
Ok(())
}
}
/// Resizes a widget surface.
pub fn resize_surface(
&self,
_scontext: &Context,
surface: &mut Surface,
size: Size2D<i32>,
) -> Result<(), Error> {
surface.size = size;
Ok(())
}
/// Returns various information about the surface, including the framebuffer object needed to
/// render to this surface.
///
/// Before rendering to a surface attached to a context, you must call `glBindFramebuffer()`
/// on the framebuffer object returned by this function. This framebuffer object may or not be
/// 0, the default framebuffer, depending on platform.
#[inline]
pub fn surface_info(&self, surface: &Surface) -> SurfaceInfo {
SurfaceInfo {
size: surface.size,
id: surface.id(),
context_id: surface.context_id,
framebuffer_object: match surface.win32_objects {
Win32Objects::Texture { gl_framebuffer, .. } => gl_framebuffer,
Win32Objects::Widget { .. } => 0,
},
}
}
/// Returns the OpenGL texture object containing the contents of this surface.
///
/// It is only legal to read from, not write to, this texture object.
#[inline]
pub fn surface_texture_object(&self, surface_texture: &SurfaceTexture) -> GLuint {
surface_texture.gl_texture
}
}
impl Surface {
pub(crate) fn id(&self) -> SurfaceID {
match self.win32_objects {
Win32Objects::Texture {
ref d3d11_texture, ..
} => SurfaceID((*d3d11_texture).as_raw() as usize),
Win32Objects::Widget { window_handle } => SurfaceID(window_handle as usize),
}
}
}
/// Represents the CPU view of the pixel data of this surface.
pub struct SurfaceDataGuard<'a> {
phantom: PhantomData<&'a ()>,
}