servo/components/script/dom/webglframebuffer.rs
2018-09-19 17:40:47 -04:00

603 lines
20 KiB
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
// https://www.khronos.org/registry/webgl/specs/latest/1.0/webgl.idl
use canvas_traits::webgl::{WebGLCommand, WebGLFramebufferBindingRequest, WebGLFramebufferId};
use canvas_traits::webgl::{WebGLResult, WebGLError, webgl_channel};
use dom::bindings::cell::DomRefCell;
use dom::bindings::codegen::Bindings::WebGLFramebufferBinding;
use dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGLRenderingContextConstants as constants;
use dom::bindings::inheritance::Castable;
use dom::bindings::reflector::{DomObject, reflect_dom_object};
use dom::bindings::root::{Dom, DomRoot};
use dom::webglobject::WebGLObject;
use dom::webglrenderbuffer::WebGLRenderbuffer;
use dom::webglrenderingcontext::WebGLRenderingContext;
use dom::webgltexture::WebGLTexture;
use dom_struct::dom_struct;
use std::cell::Cell;
pub enum CompleteForRendering {
Complete,
Incomplete,
MissingColorAttachment,
}
#[must_root]
#[derive(Clone, JSTraceable, MallocSizeOf)]
enum WebGLFramebufferAttachment {
Renderbuffer(Dom<WebGLRenderbuffer>),
Texture {
texture: Dom<WebGLTexture>,
level: i32,
},
}
impl WebGLFramebufferAttachment {
fn needs_initialization(&self) -> bool {
match *self {
WebGLFramebufferAttachment::Renderbuffer(ref r) => !r.is_initialized(),
WebGLFramebufferAttachment::Texture { .. } => false,
}
}
fn mark_initialized(&self) {
match *self {
WebGLFramebufferAttachment::Renderbuffer(ref r) => r.mark_initialized(),
WebGLFramebufferAttachment::Texture { .. } => (),
}
}
fn root(&self) -> WebGLFramebufferAttachmentRoot {
match *self {
WebGLFramebufferAttachment::Renderbuffer(ref rb) => {
WebGLFramebufferAttachmentRoot::Renderbuffer(DomRoot::from_ref(&rb))
},
WebGLFramebufferAttachment::Texture { ref texture, .. } => {
WebGLFramebufferAttachmentRoot::Texture(DomRoot::from_ref(&texture))
},
}
}
}
#[derive(Clone, JSTraceable, MallocSizeOf)]
pub enum WebGLFramebufferAttachmentRoot {
Renderbuffer(DomRoot<WebGLRenderbuffer>),
Texture(DomRoot<WebGLTexture>),
}
#[dom_struct]
pub struct WebGLFramebuffer {
webgl_object: WebGLObject,
id: WebGLFramebufferId,
/// target can only be gl::FRAMEBUFFER at the moment
target: Cell<Option<u32>>,
is_deleted: Cell<bool>,
size: Cell<Option<(i32, i32)>>,
status: Cell<u32>,
// The attachment points for textures and renderbuffers on this
// FBO.
color: DomRefCell<Option<WebGLFramebufferAttachment>>,
depth: DomRefCell<Option<WebGLFramebufferAttachment>>,
stencil: DomRefCell<Option<WebGLFramebufferAttachment>>,
depthstencil: DomRefCell<Option<WebGLFramebufferAttachment>>,
is_initialized: Cell<bool>,
}
impl WebGLFramebuffer {
fn new_inherited(context: &WebGLRenderingContext, id: WebGLFramebufferId) -> Self {
Self {
webgl_object: WebGLObject::new_inherited(context),
id: id,
target: Cell::new(None),
is_deleted: Cell::new(false),
size: Cell::new(None),
status: Cell::new(constants::FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT),
color: DomRefCell::new(None),
depth: DomRefCell::new(None),
stencil: DomRefCell::new(None),
depthstencil: DomRefCell::new(None),
is_initialized: Cell::new(false),
}
}
pub fn maybe_new(context: &WebGLRenderingContext) -> Option<DomRoot<Self>> {
let (sender, receiver) = webgl_channel().unwrap();
context.send_command(WebGLCommand::CreateFramebuffer(sender));
receiver
.recv()
.unwrap()
.map(|id| WebGLFramebuffer::new(context, id))
}
pub fn new(context: &WebGLRenderingContext, id: WebGLFramebufferId) -> DomRoot<Self> {
reflect_dom_object(
Box::new(WebGLFramebuffer::new_inherited(context, id)),
&*context.global(),
WebGLFramebufferBinding::Wrap,
)
}
}
impl WebGLFramebuffer {
pub fn id(&self) -> WebGLFramebufferId {
self.id
}
pub fn bind(&self, target: u32) {
// Update the framebuffer status on binding. It may have
// changed if its attachments were resized or deleted while
// we've been unbound.
self.update_status();
self.target.set(Some(target));
self.upcast::<WebGLObject>()
.context()
.send_command(WebGLCommand::BindFramebuffer(
target,
WebGLFramebufferBindingRequest::Explicit(self.id),
));
}
pub fn delete(&self) {
if !self.is_deleted.get() {
self.is_deleted.set(true);
self.upcast::<WebGLObject>()
.context()
.send_command(WebGLCommand::DeleteFramebuffer(self.id));
}
}
pub fn is_deleted(&self) -> bool {
self.is_deleted.get()
}
pub fn size(&self) -> Option<(i32, i32)> {
self.size.get()
}
fn update_status(&self) {
let c = self.color.borrow();
let z = self.depth.borrow();
let s = self.stencil.borrow();
let zs = self.depthstencil.borrow();
let has_c = c.is_some();
let has_z = z.is_some();
let has_s = s.is_some();
let has_zs = zs.is_some();
let attachments = [&*c, &*z, &*s, &*zs];
let attachment_constraints = [
&[
constants::RGBA4,
constants::RGB5_A1,
constants::RGB565,
constants::RGBA,
][..],
&[constants::DEPTH_COMPONENT16][..],
&[constants::STENCIL_INDEX8][..],
&[constants::DEPTH_STENCIL][..],
];
// From the WebGL spec, 6.6 ("Framebuffer Object Attachments"):
//
// "In the WebGL API, it is an error to concurrently attach
// renderbuffers to the following combinations of
// attachment points:
//
// DEPTH_ATTACHMENT + DEPTH_STENCIL_ATTACHMENT
// STENCIL_ATTACHMENT + DEPTH_STENCIL_ATTACHMENT
// DEPTH_ATTACHMENT + STENCIL_ATTACHMENT
//
// If any of the constraints above are violated, then:
//
// checkFramebufferStatus must return FRAMEBUFFER_UNSUPPORTED."
if (has_zs && (has_z || has_s)) || (has_z && has_s) {
self.status.set(constants::FRAMEBUFFER_UNSUPPORTED);
return;
}
let mut fb_size = None;
for (attachment, constraints) in attachments.iter().zip(&attachment_constraints) {
// Get the size of this attachment.
let (format, size) = match **attachment {
Some(WebGLFramebufferAttachment::Renderbuffer(ref att_rb)) => {
(Some(att_rb.internal_format()), att_rb.size())
},
Some(WebGLFramebufferAttachment::Texture {
texture: ref att_tex,
level,
}) => {
let info = att_tex.image_info_at_face(0, level as u32);
(
info.internal_format().map(|t| t.as_gl_constant()),
Some((info.width() as i32, info.height() as i32)),
)
},
None => (None, None),
};
// Make sure that, if we've found any other attachment,
// that the size matches.
if size.is_some() {
if fb_size.is_some() && size != fb_size {
self.status
.set(constants::FRAMEBUFFER_INCOMPLETE_DIMENSIONS);
return;
} else {
fb_size = size;
}
}
if let Some(format) = format {
if constraints.iter().all(|c| *c != format) {
self.status
.set(constants::FRAMEBUFFER_INCOMPLETE_ATTACHMENT);
return;
}
}
}
self.size.set(fb_size);
if has_c || has_z || has_zs || has_s {
if self.size.get().map_or(false, |(w, h)| w != 0 && h != 0) {
self.status.set(constants::FRAMEBUFFER_COMPLETE);
} else {
self.status
.set(constants::FRAMEBUFFER_INCOMPLETE_ATTACHMENT);
}
} else {
self.status
.set(constants::FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT);
}
}
pub fn check_status(&self) -> u32 {
return self.status.get();
}
pub fn check_status_for_rendering(&self) -> CompleteForRendering {
let result = self.check_status();
if result != constants::FRAMEBUFFER_COMPLETE {
return CompleteForRendering::Incomplete;
}
if self.color.borrow().is_none() {
return CompleteForRendering::MissingColorAttachment;
}
if !self.is_initialized.get() {
let attachments = [
(&self.color, constants::COLOR_BUFFER_BIT),
(&self.depth, constants::DEPTH_BUFFER_BIT),
(&self.stencil, constants::STENCIL_BUFFER_BIT),
(
&self.depthstencil,
constants::DEPTH_BUFFER_BIT | constants::STENCIL_BUFFER_BIT,
),
];
let mut clear_bits = 0;
for &(attachment, bits) in &attachments {
if let Some(ref att) = *attachment.borrow() {
if att.needs_initialization() {
att.mark_initialized();
clear_bits |= bits;
}
}
}
self.upcast::<WebGLObject>()
.context()
.initialize_framebuffer(clear_bits);
self.is_initialized.set(true);
}
CompleteForRendering::Complete
}
pub fn renderbuffer(&self, attachment: u32, rb: Option<&WebGLRenderbuffer>) -> WebGLResult<()> {
let binding = self
.attachment_binding(attachment)
.ok_or(WebGLError::InvalidEnum)?;
let rb_id = match rb {
Some(rb) => {
if !rb.ever_bound() {
return Err(WebGLError::InvalidOperation);
}
*binding.borrow_mut() =
Some(WebGLFramebufferAttachment::Renderbuffer(Dom::from_ref(rb)));
Some(rb.id())
},
_ => None,
};
self.upcast::<WebGLObject>()
.context()
.send_command(WebGLCommand::FramebufferRenderbuffer(
constants::FRAMEBUFFER,
attachment,
constants::RENDERBUFFER,
rb_id,
));
if rb.is_none() {
self.detach_binding(binding, attachment);
}
self.update_status();
self.is_initialized.set(false);
Ok(())
}
fn detach_binding(
&self,
binding: &DomRefCell<Option<WebGLFramebufferAttachment>>,
attachment: u32,
) {
*binding.borrow_mut() = None;
if INTERESTING_ATTACHMENT_POINTS.contains(&attachment) {
self.reattach_depth_stencil();
}
}
fn attachment_binding(
&self,
attachment: u32,
) -> Option<&DomRefCell<Option<WebGLFramebufferAttachment>>> {
match attachment {
constants::COLOR_ATTACHMENT0 => Some(&self.color),
constants::DEPTH_ATTACHMENT => Some(&self.depth),
constants::STENCIL_ATTACHMENT => Some(&self.stencil),
constants::DEPTH_STENCIL_ATTACHMENT => Some(&self.depthstencil),
_ => None,
}
}
fn reattach_depth_stencil(&self) {
let reattach = |attachment: &WebGLFramebufferAttachment, attachment_point| {
let context = self.upcast::<WebGLObject>().context();
match *attachment {
WebGLFramebufferAttachment::Renderbuffer(ref rb) => {
context.send_command(WebGLCommand::FramebufferRenderbuffer(
constants::FRAMEBUFFER,
attachment_point,
constants::RENDERBUFFER,
Some(rb.id()),
));
},
WebGLFramebufferAttachment::Texture { ref texture, level } => {
context.send_command(WebGLCommand::FramebufferTexture2D(
constants::FRAMEBUFFER,
attachment_point,
texture.target().expect("missing texture target"),
Some(texture.id()),
level,
));
},
}
};
// Since the DEPTH_STENCIL attachment causes both the DEPTH and STENCIL
// attachments to be overwritten, we need to ensure that we reattach
// the DEPTH and STENCIL attachments when any of those attachments
// is cleared.
if let Some(ref depth) = *self.depth.borrow() {
reattach(depth, constants::DEPTH_ATTACHMENT);
}
if let Some(ref stencil) = *self.stencil.borrow() {
reattach(stencil, constants::STENCIL_ATTACHMENT);
}
if let Some(ref depth_stencil) = *self.depthstencil.borrow() {
reattach(depth_stencil, constants::DEPTH_STENCIL_ATTACHMENT);
}
}
pub fn attachment(&self, attachment: u32) -> Option<WebGLFramebufferAttachmentRoot> {
let binding = self.attachment_binding(attachment)?;
binding
.borrow()
.as_ref()
.map(WebGLFramebufferAttachment::root)
}
pub fn texture2d(
&self,
attachment: u32,
textarget: u32,
texture: Option<&WebGLTexture>,
level: i32,
) -> WebGLResult<()> {
let binding = self
.attachment_binding(attachment)
.ok_or(WebGLError::InvalidEnum)?;
let tex_id = match texture {
// Note, from the GLES 2.0.25 spec, page 113:
// "If texture is zero, then textarget and level are ignored."
Some(texture) => {
// From the GLES 2.0.25 spec, page 113:
//
// "level specifies the mipmap level of the texture image
// to be attached to the framebuffer and must be
// 0. Otherwise, INVALID_VALUE is generated."
if level != 0 {
return Err(WebGLError::InvalidValue);
}
// "If texture is not zero, then texture must either
// name an existing texture object with an target of
// textarget, or texture must name an existing cube
// map texture and textarget must be one of:
// TEXTURE_CUBE_MAP_POSITIVE_X,
// TEXTURE_CUBE_MAP_POSITIVE_Y,
// TEXTURE_CUBE_MAP_POSITIVE_Z,
// TEXTURE_CUBE_MAP_NEGATIVE_X,
// TEXTURE_CUBE_MAP_NEGATIVE_Y, or
// TEXTURE_CUBE_MAP_NEGATIVE_Z. Otherwise,
// INVALID_OPERATION is generated."
let is_cube = match textarget {
constants::TEXTURE_2D => false,
constants::TEXTURE_CUBE_MAP_POSITIVE_X => true,
constants::TEXTURE_CUBE_MAP_POSITIVE_Y => true,
constants::TEXTURE_CUBE_MAP_POSITIVE_Z => true,
constants::TEXTURE_CUBE_MAP_NEGATIVE_X => true,
constants::TEXTURE_CUBE_MAP_NEGATIVE_Y => true,
constants::TEXTURE_CUBE_MAP_NEGATIVE_Z => true,
_ => return Err(WebGLError::InvalidEnum),
};
match texture.target() {
Some(constants::TEXTURE_CUBE_MAP) if is_cube => {},
Some(_) if !is_cube => {},
_ => return Err(WebGLError::InvalidOperation),
}
*binding.borrow_mut() = Some(WebGLFramebufferAttachment::Texture {
texture: Dom::from_ref(texture),
level: level,
});
Some(texture.id())
},
_ => None,
};
self.upcast::<WebGLObject>()
.context()
.send_command(WebGLCommand::FramebufferTexture2D(
constants::FRAMEBUFFER,
attachment,
textarget,
tex_id,
level,
));
if texture.is_none() {
self.detach_binding(binding, attachment);
}
self.update_status();
self.is_initialized.set(false);
Ok(())
}
fn with_matching_renderbuffers<F>(&self, rb: &WebGLRenderbuffer, mut closure: F)
where
F: FnMut(&DomRefCell<Option<WebGLFramebufferAttachment>>, u32),
{
let attachments = [
(&self.color, constants::COLOR_ATTACHMENT0),
(&self.depth, constants::DEPTH_ATTACHMENT),
(&self.stencil, constants::STENCIL_ATTACHMENT),
(&self.depthstencil, constants::DEPTH_STENCIL_ATTACHMENT),
];
for (attachment, name) in &attachments {
let matched = {
match *attachment.borrow() {
Some(WebGLFramebufferAttachment::Renderbuffer(ref att_rb))
if rb.id() == att_rb.id() =>
{
true
},
_ => false,
}
};
if matched {
closure(attachment, *name);
}
}
}
fn with_matching_textures<F>(&self, texture: &WebGLTexture, mut closure: F)
where
F: FnMut(&DomRefCell<Option<WebGLFramebufferAttachment>>, u32),
{
let attachments = [
(&self.color, constants::COLOR_ATTACHMENT0),
(&self.depth, constants::DEPTH_ATTACHMENT),
(&self.stencil, constants::STENCIL_ATTACHMENT),
(&self.depthstencil, constants::DEPTH_STENCIL_ATTACHMENT),
];
for (attachment, name) in &attachments {
let matched = {
match *attachment.borrow() {
Some(WebGLFramebufferAttachment::Texture {
texture: ref att_texture,
..
})
if texture.id() == att_texture.id() =>
{
true
},
_ => false,
}
};
if matched {
closure(attachment, *name);
}
}
}
pub fn detach_renderbuffer(&self, rb: &WebGLRenderbuffer) {
let mut depth_or_stencil_updated = false;
self.with_matching_renderbuffers(rb, |att, name| {
depth_or_stencil_updated |= INTERESTING_ATTACHMENT_POINTS.contains(&name);
*att.borrow_mut() = None;
self.update_status();
});
if depth_or_stencil_updated {
self.reattach_depth_stencil();
}
}
pub fn detach_texture(&self, texture: &WebGLTexture) {
let mut depth_or_stencil_updated = false;
self.with_matching_textures(texture, |att, name| {
depth_or_stencil_updated |= INTERESTING_ATTACHMENT_POINTS.contains(&name);
*att.borrow_mut() = None;
self.update_status();
});
if depth_or_stencil_updated {
self.reattach_depth_stencil();
}
}
pub fn invalidate_renderbuffer(&self, rb: &WebGLRenderbuffer) {
self.with_matching_renderbuffers(rb, |_att, _| {
self.is_initialized.set(false);
self.update_status();
});
}
pub fn invalidate_texture(&self, texture: &WebGLTexture) {
self.with_matching_textures(texture, |_att, _name| {
self.update_status();
});
}
pub fn target(&self) -> Option<u32> {
self.target.get()
}
}
impl Drop for WebGLFramebuffer {
fn drop(&mut self) {
self.delete();
}
}
static INTERESTING_ATTACHMENT_POINTS: &[u32] = &[
constants::DEPTH_ATTACHMENT,
constants::STENCIL_ATTACHMENT,
constants::DEPTH_STENCIL_ATTACHMENT,
];