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::rc::Rc;
9use std::sync::Once;
10
11use dom_struct::dom_struct;
12use js::context::JSContext;
13use mozangle::shaders::{BuiltInResources, CompileOptions, Output, ShaderValidator};
14use script_bindings::cell::DomRefCell;
15use script_bindings::reflector::reflect_weak_referenceable_dom_object;
16use script_bindings::weakref::WeakRef;
17use servo_canvas_traits::webgl::{
18    GLLimits, GlType, WebGLCommand, WebGLError, WebGLResult, WebGLSLVersion, WebGLShaderId,
19    WebGLVersion, webgl_channel,
20};
21
22use crate::dom::bindings::inheritance::Castable;
23use crate::dom::bindings::reflector::DomGlobal;
24use crate::dom::bindings::root::DomRoot;
25use crate::dom::bindings::str::DOMString;
26use crate::dom::webgl::extensions::WebGLExtensions;
27use crate::dom::webgl::extensions::extfragdepth::EXTFragDepth;
28use crate::dom::webgl::extensions::extshadertexturelod::EXTShaderTextureLod;
29use crate::dom::webgl::extensions::oesstandardderivatives::OESStandardDerivatives;
30use crate::dom::webgl::webglobject::WebGLObject;
31use crate::dom::webgl::webglrenderingcontext::{Operation, WebGLRenderingContext};
32use crate::dom::webglrenderingcontext::capture_webgl_backtrace;
33
34#[derive(Clone, Copy, Debug, JSTraceable, MallocSizeOf, PartialEq)]
35pub(crate) enum ShaderCompilationStatus {
36    NotCompiled,
37    Succeeded,
38    Failed,
39}
40
41#[derive(JSTraceable, MallocSizeOf)]
42struct DroppableWebGLShader {
43    context: WeakRef<WebGLRenderingContext>,
44    #[no_trace]
45    id: WebGLShaderId,
46    marked_for_deletion: Cell<bool>,
47}
48
49impl DroppableWebGLShader {
50    fn send_with_fallibility(&self, command: WebGLCommand, fallibility: Operation) {
51        if let Some(root) = self.context.root() {
52            let result = root.sender().send(command, capture_webgl_backtrace());
53            if matches!(fallibility, Operation::Infallible) {
54                result.expect("Operation failed");
55            }
56        }
57    }
58
59    fn mark_for_deletion(&self, operation_fallibility: Operation) {
60        if !self.marked_for_deletion.get() {
61            self.marked_for_deletion.set(true);
62            self.send_with_fallibility(WebGLCommand::DeleteShader(self.id), operation_fallibility);
63        }
64    }
65}
66
67impl Drop for DroppableWebGLShader {
68    fn drop(&mut self) {
69        self.mark_for_deletion(Operation::Fallible);
70    }
71}
72
73#[dom_struct(associated_memory)]
74pub(crate) struct WebGLShader {
75    webgl_object: WebGLObject,
76    gl_type: u32,
77    source: DomRefCell<DOMString>,
78    info_log: DomRefCell<DOMString>,
79    attached_counter: Cell<u32>,
80    compilation_status: Cell<ShaderCompilationStatus>,
81    droppable: DroppableWebGLShader,
82}
83
84static GLSLANG_INITIALIZATION: Once = Once::new();
85
86impl WebGLShader {
87    fn new_inherited(context: &WebGLRenderingContext, id: WebGLShaderId, shader_type: u32) -> Self {
88        GLSLANG_INITIALIZATION.call_once(|| ::mozangle::shaders::initialize().unwrap());
89        Self {
90            webgl_object: WebGLObject::new_inherited(context),
91            gl_type: shader_type,
92            source: Default::default(),
93            info_log: Default::default(),
94            attached_counter: Cell::new(0),
95            compilation_status: Cell::new(ShaderCompilationStatus::NotCompiled),
96            droppable: DroppableWebGLShader {
97                context: WeakRef::new(context),
98                id,
99                marked_for_deletion: Cell::new(false),
100            },
101        }
102    }
103
104    pub(crate) fn maybe_new(
105        cx: &mut JSContext,
106        context: &WebGLRenderingContext,
107        shader_type: u32,
108    ) -> Option<DomRoot<Self>> {
109        let (sender, receiver) = webgl_channel().unwrap();
110        context.send_command(WebGLCommand::CreateShader(shader_type, sender));
111        receiver
112            .recv()
113            .unwrap()
114            .map(|id| WebGLShader::new(cx, context, id, shader_type))
115    }
116
117    pub(crate) fn new(
118        cx: &mut JSContext,
119        context: &WebGLRenderingContext,
120        id: WebGLShaderId,
121        shader_type: u32,
122    ) -> DomRoot<Self> {
123        reflect_weak_referenceable_dom_object(
124            cx,
125            Rc::new(WebGLShader::new_inherited(context, id, shader_type)),
126            &*context.global(),
127        )
128    }
129}
130
131impl WebGLShader {
132    pub(crate) fn id(&self) -> WebGLShaderId {
133        self.droppable.id
134    }
135
136    pub(crate) fn gl_type(&self) -> u32 {
137        self.gl_type
138    }
139
140    /// glCompileShader
141    pub(crate) fn compile(
142        &self,
143        api_type: GlType,
144        webgl_version: WebGLVersion,
145        glsl_version: WebGLSLVersion,
146        limits: &GLLimits,
147        ext: &WebGLExtensions,
148    ) -> WebGLResult<()> {
149        if self.droppable.marked_for_deletion.get() && !self.is_attached() {
150            return Err(WebGLError::InvalidValue);
151        }
152        if self.compilation_status.get() != ShaderCompilationStatus::NotCompiled {
153            debug!("Compiling already compiled shader {}", self.id());
154        }
155
156        let source = self.source.borrow();
157
158        let mut params = BuiltInResources {
159            MaxVertexAttribs: limits.max_vertex_attribs as c_int,
160            MaxVertexUniformVectors: limits.max_vertex_uniform_vectors as c_int,
161            MaxVertexTextureImageUnits: limits.max_vertex_texture_image_units as c_int,
162            MaxCombinedTextureImageUnits: limits.max_combined_texture_image_units as c_int,
163            MaxTextureImageUnits: limits.max_texture_image_units as c_int,
164            MaxFragmentUniformVectors: limits.max_fragment_uniform_vectors as c_int,
165
166            MaxVertexOutputVectors: limits.max_vertex_output_vectors as c_int,
167            MaxFragmentInputVectors: limits.max_fragment_input_vectors as c_int,
168            MaxVaryingVectors: limits.max_varying_vectors as c_int,
169
170            OES_standard_derivatives: ext.is_enabled::<OESStandardDerivatives>() as c_int,
171            EXT_shader_texture_lod: ext.is_enabled::<EXTShaderTextureLod>() as c_int,
172            EXT_frag_depth: ext.is_enabled::<EXTFragDepth>() as c_int,
173
174            FragmentPrecisionHigh: 1,
175            ..Default::default()
176        };
177
178        if webgl_version == WebGLVersion::WebGL2 {
179            params.MinProgramTexelOffset = limits.min_program_texel_offset as c_int;
180            params.MaxProgramTexelOffset = limits.max_program_texel_offset as c_int;
181            params.MaxDrawBuffers = limits.max_draw_buffers as c_int;
182        }
183
184        let validator = match webgl_version {
185            WebGLVersion::WebGL1 => {
186                let output_format = if api_type == GlType::Gles {
187                    Output::Essl
188                } else {
189                    Output::Glsl
190                };
191                ShaderValidator::for_webgl(self.gl_type, output_format, &params).unwrap()
192            },
193            WebGLVersion::WebGL2 => {
194                let output_format = if api_type == GlType::Gles {
195                    Output::Essl
196                } else {
197                    match (glsl_version.major, glsl_version.minor) {
198                        (1, 30) => Output::Glsl130,
199                        (1, 40) => Output::Glsl140,
200                        (1, 50) => Output::Glsl150Core,
201                        (3, 30) => Output::Glsl330Core,
202                        (4, 0) => Output::Glsl400Core,
203                        (4, 10) => Output::Glsl410Core,
204                        (4, 20) => Output::Glsl420Core,
205                        (4, 30) => Output::Glsl430Core,
206                        (4, 40) => Output::Glsl440Core,
207                        (4, _) => Output::Glsl450Core,
208                        _ => Output::Glsl140,
209                    }
210                };
211                ShaderValidator::for_webgl2(self.gl_type, output_format, &params).unwrap()
212            },
213        };
214
215        // Replicating
216        // https://searchfox.org/mozilla-esr115/rev/f1fb0868dc63b89ccf9eea157960d1ec27fb55a2/dom/canvas/WebGLShaderValidator.cpp#29
217        let mut options = CompileOptions::mozangle();
218        options.set_variables(1);
219        options.set_enforcePackingRestrictions(1);
220        options.set_objectCode(1);
221        options.set_initGLPosition(1);
222        options.set_initializeUninitializedLocals(1);
223        options.set_initOutputVariables(1);
224
225        options.set_limitExpressionComplexity(1);
226        options.set_limitCallStackDepth(1);
227
228        if cfg!(target_os = "macos") {
229            options.set_removeInvariantAndCentroidForESSL3(1);
230
231            // Work around https://bugs.webkit.org/show_bug.cgi?id=124684,
232            // https://chromium.googlesource.com/angle/angle/+/5e70cf9d0b1bb
233            options.set_unfoldShortCircuit(1);
234            // Work around that Mac drivers handle struct scopes incorrectly.
235            options.set_regenerateStructNames(1);
236            // TODO: Only apply this workaround to Intel hardware
237            // Work around that Intel drivers on Mac OSX handle for-loop incorrectly.
238            options.set_addAndTrueToLoopCondition(1);
239            options.set_rewriteTexelFetchOffsetToTexelFetch(1);
240        } else {
241            // We want to do this everywhere, but to do this on Mac, we need
242            // to do it only on Mac OSX > 10.6 as this causes the shader
243            // compiler in 10.6 to crash
244            options.set_clampIndirectArrayBounds(1);
245        }
246
247        match validator.compile(&[&source.str()], options) {
248            Ok(()) => {
249                let translated_source = validator.object_code();
250                debug!("Shader translated: {}", translated_source);
251                // NOTE: At this point we should be pretty sure that the compilation in the paint thread
252                // will succeed.
253                // It could be interesting to retrieve the info log from the paint thread though
254                self.upcast()
255                    .send_command(WebGLCommand::CompileShader(self.id(), translated_source));
256                self.compilation_status
257                    .set(ShaderCompilationStatus::Succeeded);
258            },
259            Err(error) => {
260                self.compilation_status.set(ShaderCompilationStatus::Failed);
261                debug!("Shader {} compilation failed: {}", self.id(), error);
262            },
263        }
264
265        *self.info_log.borrow_mut() = validator.info_log().into();
266
267        Ok(())
268    }
269
270    /// Mark this shader as deleted (if it wasn't previously)
271    /// and delete it as if calling glDeleteShader.
272    /// Currently does not check if shader is attached
273    pub(crate) fn mark_for_deletion(&self, operation_fallibility: Operation) {
274        self.droppable.mark_for_deletion(operation_fallibility);
275    }
276
277    pub(crate) fn is_marked_for_deletion(&self) -> bool {
278        self.droppable.marked_for_deletion.get()
279    }
280
281    pub(crate) fn is_deleted(&self) -> bool {
282        self.droppable.marked_for_deletion.get() && !self.is_attached()
283    }
284
285    pub(crate) fn is_attached(&self) -> bool {
286        self.attached_counter.get() > 0
287    }
288
289    pub(crate) fn increment_attached_counter(&self) {
290        self.attached_counter.set(self.attached_counter.get() + 1);
291    }
292
293    pub(crate) fn decrement_attached_counter(&self) {
294        assert!(self.attached_counter.get() > 0);
295        self.attached_counter.set(self.attached_counter.get() - 1);
296    }
297
298    /// glGetShaderInfoLog
299    pub(crate) fn info_log(&self) -> DOMString {
300        self.info_log.borrow().clone()
301    }
302
303    /// Get the shader source
304    pub(crate) fn source(&self) -> DOMString {
305        self.source.borrow().clone()
306    }
307
308    /// glShaderSource
309    pub(crate) fn set_source(&self, source: DOMString) {
310        *self.source.borrow_mut() = source;
311    }
312
313    pub(crate) fn successfully_compiled(&self) -> bool {
314        self.compilation_status.get() == ShaderCompilationStatus::Succeeded
315    }
316}
script/dom/webgl/webglshader.rs

script/dom/webgl/
webglshader.rs
