script/dom/webgl/
webglshader.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5// https://www.khronos.org/registry/webgl/specs/latest/1.0/webgl.idl
6use std::cell::Cell;
7use std::os::raw::c_int;
8use std::sync::Once;
9
10use dom_struct::dom_struct;
11use mozangle::shaders::{BuiltInResources, CompileOptions, Output, ShaderValidator};
12use script_bindings::cell::DomRefCell;
13use script_bindings::reflector::reflect_dom_object;
14use script_bindings::weakref::WeakRef;
15use servo_canvas_traits::webgl::{
16    GLLimits, GlType, WebGLCommand, WebGLError, WebGLResult, WebGLSLVersion, WebGLShaderId,
17    WebGLVersion, webgl_channel,
18};
19
20use crate::dom::bindings::inheritance::Castable;
21use crate::dom::bindings::reflector::DomGlobal;
22use crate::dom::bindings::root::DomRoot;
23use crate::dom::bindings::str::DOMString;
24use crate::dom::webgl::extensions::WebGLExtensions;
25use crate::dom::webgl::extensions::extfragdepth::EXTFragDepth;
26use crate::dom::webgl::extensions::extshadertexturelod::EXTShaderTextureLod;
27use crate::dom::webgl::extensions::oesstandardderivatives::OESStandardDerivatives;
28use crate::dom::webgl::webglobject::WebGLObject;
29use crate::dom::webgl::webglrenderingcontext::{Operation, WebGLRenderingContext};
30use crate::dom::webglrenderingcontext::capture_webgl_backtrace;
31use crate::script_runtime::CanGc;
32
33#[derive(Clone, Copy, Debug, JSTraceable, MallocSizeOf, PartialEq)]
34pub(crate) enum ShaderCompilationStatus {
35    NotCompiled,
36    Succeeded,
37    Failed,
38}
39
40#[derive(JSTraceable, MallocSizeOf)]
41struct DroppableWebGLShader {
42    context: WeakRef<WebGLRenderingContext>,
43    #[no_trace]
44    id: WebGLShaderId,
45    marked_for_deletion: Cell<bool>,
46}
47
48impl DroppableWebGLShader {
49    fn send_with_fallibility(&self, command: WebGLCommand, fallibility: Operation) {
50        if let Some(root) = self.context.root() {
51            let result = root.sender().send(command, capture_webgl_backtrace());
52            if matches!(fallibility, Operation::Infallible) {
53                result.expect("Operation failed");
54            }
55        }
56    }
57
58    fn mark_for_deletion(&self, operation_fallibility: Operation) {
59        if !self.marked_for_deletion.get() {
60            self.marked_for_deletion.set(true);
61            self.send_with_fallibility(WebGLCommand::DeleteShader(self.id), operation_fallibility);
62        }
63    }
64}
65
66impl Drop for DroppableWebGLShader {
67    fn drop(&mut self) {
68        self.mark_for_deletion(Operation::Fallible);
69    }
70}
71
72#[dom_struct(associated_memory)]
73pub(crate) struct WebGLShader {
74    webgl_object: WebGLObject,
75    gl_type: u32,
76    source: DomRefCell<DOMString>,
77    info_log: DomRefCell<DOMString>,
78    attached_counter: Cell<u32>,
79    compilation_status: Cell<ShaderCompilationStatus>,
80    droppable: DroppableWebGLShader,
81}
82
83static GLSLANG_INITIALIZATION: Once = Once::new();
84
85impl WebGLShader {
86    fn new_inherited(context: &WebGLRenderingContext, id: WebGLShaderId, shader_type: u32) -> Self {
87        GLSLANG_INITIALIZATION.call_once(|| ::mozangle::shaders::initialize().unwrap());
88        Self {
89            webgl_object: WebGLObject::new_inherited(context),
90            gl_type: shader_type,
91            source: Default::default(),
92            info_log: Default::default(),
93            attached_counter: Cell::new(0),
94            compilation_status: Cell::new(ShaderCompilationStatus::NotCompiled),
95            droppable: DroppableWebGLShader {
96                context: WeakRef::new(context),
97                id,
98                marked_for_deletion: Cell::new(false),
99            },
100        }
101    }
102
103    pub(crate) fn maybe_new(
104        context: &WebGLRenderingContext,
105        shader_type: u32,
106    ) -> Option<DomRoot<Self>> {
107        let (sender, receiver) = webgl_channel().unwrap();
108        context.send_command(WebGLCommand::CreateShader(shader_type, sender));
109        receiver
110            .recv()
111            .unwrap()
112            .map(|id| WebGLShader::new(context, id, shader_type, CanGc::deprecated_note()))
113    }
114
115    pub(crate) fn new(
116        context: &WebGLRenderingContext,
117        id: WebGLShaderId,
118        shader_type: u32,
119        can_gc: CanGc,
120    ) -> DomRoot<Self> {
121        reflect_dom_object(
122            Box::new(WebGLShader::new_inherited(context, id, shader_type)),
123            &*context.global(),
124            can_gc,
125        )
126    }
127}
128
129impl WebGLShader {
130    pub(crate) fn id(&self) -> WebGLShaderId {
131        self.droppable.id
132    }
133
134    pub(crate) fn gl_type(&self) -> u32 {
135        self.gl_type
136    }
137
138    /// glCompileShader
139    pub(crate) fn compile(
140        &self,
141        api_type: GlType,
142        webgl_version: WebGLVersion,
143        glsl_version: WebGLSLVersion,
144        limits: &GLLimits,
145        ext: &WebGLExtensions,
146    ) -> WebGLResult<()> {
147        if self.droppable.marked_for_deletion.get() && !self.is_attached() {
148            return Err(WebGLError::InvalidValue);
149        }
150        if self.compilation_status.get() != ShaderCompilationStatus::NotCompiled {
151            debug!("Compiling already compiled shader {}", self.id());
152        }
153
154        let source = self.source.borrow();
155
156        let mut params = BuiltInResources {
157            MaxVertexAttribs: limits.max_vertex_attribs as c_int,
158            MaxVertexUniformVectors: limits.max_vertex_uniform_vectors as c_int,
159            MaxVertexTextureImageUnits: limits.max_vertex_texture_image_units as c_int,
160            MaxCombinedTextureImageUnits: limits.max_combined_texture_image_units as c_int,
161            MaxTextureImageUnits: limits.max_texture_image_units as c_int,
162            MaxFragmentUniformVectors: limits.max_fragment_uniform_vectors as c_int,
163
164            MaxVertexOutputVectors: limits.max_vertex_output_vectors as c_int,
165            MaxFragmentInputVectors: limits.max_fragment_input_vectors as c_int,
166            MaxVaryingVectors: limits.max_varying_vectors as c_int,
167
168            OES_standard_derivatives: ext.is_enabled::<OESStandardDerivatives>() as c_int,
169            EXT_shader_texture_lod: ext.is_enabled::<EXTShaderTextureLod>() as c_int,
170            EXT_frag_depth: ext.is_enabled::<EXTFragDepth>() as c_int,
171
172            FragmentPrecisionHigh: 1,
173            ..Default::default()
174        };
175
176        if webgl_version == WebGLVersion::WebGL2 {
177            params.MinProgramTexelOffset = limits.min_program_texel_offset as c_int;
178            params.MaxProgramTexelOffset = limits.max_program_texel_offset as c_int;
179            params.MaxDrawBuffers = limits.max_draw_buffers as c_int;
180        }
181
182        let validator = match webgl_version {
183            WebGLVersion::WebGL1 => {
184                let output_format = if api_type == GlType::Gles {
185                    Output::Essl
186                } else {
187                    Output::Glsl
188                };
189                ShaderValidator::for_webgl(self.gl_type, output_format, &params).unwrap()
190            },
191            WebGLVersion::WebGL2 => {
192                let output_format = if api_type == GlType::Gles {
193                    Output::Essl
194                } else {
195                    match (glsl_version.major, glsl_version.minor) {
196                        (1, 30) => Output::Glsl130,
197                        (1, 40) => Output::Glsl140,
198                        (1, 50) => Output::Glsl150Core,
199                        (3, 30) => Output::Glsl330Core,
200                        (4, 0) => Output::Glsl400Core,
201                        (4, 10) => Output::Glsl410Core,
202                        (4, 20) => Output::Glsl420Core,
203                        (4, 30) => Output::Glsl430Core,
204                        (4, 40) => Output::Glsl440Core,
205                        (4, _) => Output::Glsl450Core,
206                        _ => Output::Glsl140,
207                    }
208                };
209                ShaderValidator::for_webgl2(self.gl_type, output_format, &params).unwrap()
210            },
211        };
212
213        // Replicating
214        // https://searchfox.org/mozilla-esr115/rev/f1fb0868dc63b89ccf9eea157960d1ec27fb55a2/dom/canvas/WebGLShaderValidator.cpp#29
215        let mut options = CompileOptions::mozangle();
216        options.set_variables(1);
217        options.set_enforcePackingRestrictions(1);
218        options.set_objectCode(1);
219        options.set_initGLPosition(1);
220        options.set_initializeUninitializedLocals(1);
221        options.set_initOutputVariables(1);
222
223        options.set_limitExpressionComplexity(1);
224        options.set_limitCallStackDepth(1);
225
226        if cfg!(target_os = "macos") {
227            options.set_removeInvariantAndCentroidForESSL3(1);
228
229            // Work around https://bugs.webkit.org/show_bug.cgi?id=124684,
230            // https://chromium.googlesource.com/angle/angle/+/5e70cf9d0b1bb
231            options.set_unfoldShortCircuit(1);
232            // Work around that Mac drivers handle struct scopes incorrectly.
233            options.set_regenerateStructNames(1);
234            // TODO: Only apply this workaround to Intel hardware
235            // Work around that Intel drivers on Mac OSX handle for-loop incorrectly.
236            options.set_addAndTrueToLoopCondition(1);
237            options.set_rewriteTexelFetchOffsetToTexelFetch(1);
238        } else {
239            // We want to do this everywhere, but to do this on Mac, we need
240            // to do it only on Mac OSX > 10.6 as this causes the shader
241            // compiler in 10.6 to crash
242            options.set_clampIndirectArrayBounds(1);
243        }
244
245        match validator.compile(&[&source.str()], options) {
246            Ok(()) => {
247                let translated_source = validator.object_code();
248                debug!("Shader translated: {}", translated_source);
249                // NOTE: At this point we should be pretty sure that the compilation in the paint thread
250                // will succeed.
251                // It could be interesting to retrieve the info log from the paint thread though
252                self.upcast()
253                    .send_command(WebGLCommand::CompileShader(self.id(), translated_source));
254                self.compilation_status
255                    .set(ShaderCompilationStatus::Succeeded);
256            },
257            Err(error) => {
258                self.compilation_status.set(ShaderCompilationStatus::Failed);
259                debug!("Shader {} compilation failed: {}", self.id(), error);
260            },
261        }
262
263        *self.info_log.borrow_mut() = validator.info_log().into();
264
265        Ok(())
266    }
267
268    /// Mark this shader as deleted (if it wasn't previously)
269    /// and delete it as if calling glDeleteShader.
270    /// Currently does not check if shader is attached
271    pub(crate) fn mark_for_deletion(&self, operation_fallibility: Operation) {
272        self.droppable.mark_for_deletion(operation_fallibility);
273    }
274
275    pub(crate) fn is_marked_for_deletion(&self) -> bool {
276        self.droppable.marked_for_deletion.get()
277    }
278
279    pub(crate) fn is_deleted(&self) -> bool {
280        self.droppable.marked_for_deletion.get() && !self.is_attached()
281    }
282
283    pub(crate) fn is_attached(&self) -> bool {
284        self.attached_counter.get() > 0
285    }
286
287    pub(crate) fn increment_attached_counter(&self) {
288        self.attached_counter.set(self.attached_counter.get() + 1);
289    }
290
291    pub(crate) fn decrement_attached_counter(&self) {
292        assert!(self.attached_counter.get() > 0);
293        self.attached_counter.set(self.attached_counter.get() - 1);
294    }
295
296    /// glGetShaderInfoLog
297    pub(crate) fn info_log(&self) -> DOMString {
298        self.info_log.borrow().clone()
299    }
300
301    /// Get the shader source
302    pub(crate) fn source(&self) -> DOMString {
303        self.source.borrow().clone()
304    }
305
306    /// glShaderSource
307    pub(crate) fn set_source(&self, source: DOMString) {
308        *self.source.borrow_mut() = source;
309    }
310
311    pub(crate) fn successfully_compiled(&self) -> bool {
312        self.compilation_status.get() == ShaderCompilationStatus::Succeeded
313    }
314}
script/dom/webgl/webglshader.rs

script/dom/webgl/
webglshader.rs
