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 http://mozilla.org/MPL/2.0/. */
6 extern crate glsl_to_cxx;
7 extern crate webrender_build;
9 use std::collections::HashSet;
11 use webrender_build::shader::{ShaderFeatureFlags, get_shader_features};
13 // Shader key is in "name feature,feature" format.
14 // File name needs to be formatted as "name_feature_feature".
15 fn shader_file(shader_key: &str) -> String {
16 shader_key.replace(' ', "_").replace(',', "_")
19 fn write_load_shader(shader_keys: &[String]) {
20 let mut load_shader = String::new();
21 for s in shader_keys {
22 let _ = write!(load_shader, "#include \"{}.h\"\n", shader_file(s));
24 load_shader.push_str("ProgramLoader load_shader(const char* name) {\n");
25 for s in shader_keys {
26 let _ = write!(load_shader, " if (!strcmp(name, \"{}\")) {{ return {}_program::loader; }}\n",
29 load_shader.push_str(" return nullptr;\n}\n");
30 std::fs::write(std::env::var("OUT_DIR").unwrap() + "/load_shader.h", load_shader).unwrap();
33 fn process_imports(shader_dir: &str, shader: &str, included: &mut HashSet<String>, output: &mut String) {
34 if !included.insert(shader.into()) {
37 println!("cargo:rerun-if-changed={}/{}.glsl", shader_dir, shader);
38 let source = std::fs::read_to_string(format!("{}/{}.glsl", shader_dir, shader)).unwrap();
39 for line in source.lines() {
40 if line.starts_with("#include ") {
41 let imports = line["#include ".len() ..].split(',');
42 for import in imports {
43 process_imports(shader_dir, import, included, output);
45 } else if line.starts_with("#version ") || line.starts_with("#extension ") {
48 output.push_str(line);
54 fn translate_shader(shader_key: &str, shader_dir: &str) {
55 let mut imported = String::from("#define SWGL 1\n#define __VERSION__ 150\n");
56 let _ = write!(imported, "#define WR_MAX_VERTEX_TEXTURE_WIDTH {}U\n",
57 webrender_build::MAX_VERTEX_TEXTURE_WIDTH);
59 let (basename, features) =
60 shader_key.split_at(shader_key.find(' ').unwrap_or(shader_key.len()));
61 if !features.is_empty() {
62 for feature in features.trim().split(',') {
63 let _ = write!(imported, "#define WR_FEATURE_{}\n", feature);
67 process_imports(shader_dir, basename, &mut HashSet::new(), &mut imported);
69 let shader = shader_file(shader_key);
71 let out_dir = std::env::var("OUT_DIR").unwrap();
72 let imp_name = format!("{}/{}.c", out_dir, shader);
73 std::fs::write(&imp_name, imported).unwrap();
75 let mut build = cc::Build::new();
76 build.no_default_flags(true);
77 if let Ok(tool) = build.try_get_compiler() {
78 if tool.is_like_msvc() {
80 if tool.path().to_str().map_or(false, |p| p.contains("clang")) {
81 build.flag("/clang:-undef");
86 build.flag("-xc").flag("-P").flag("-undef");
89 // Use SWGLPP target to avoid pulling CFLAGS/CXXFLAGS.
90 build.target("SWGLPP");
91 build.file(&imp_name);
92 let vs = build.clone()
93 .define("WR_VERTEX_SHADER", Some("1"))
95 let fs = build.clone()
96 .define("WR_FRAGMENT_SHADER", Some("1"))
98 let vs_name = format!("{}/{}.vert", out_dir, shader);
99 let fs_name = format!("{}/{}.frag", out_dir, shader);
100 std::fs::write(&vs_name, vs).unwrap();
101 std::fs::write(&fs_name, fs).unwrap();
104 "glsl_to_cxx".to_string(),
108 let result = glsl_to_cxx::translate(&mut args.into_iter());
109 std::fs::write(format!("{}/{}.h", out_dir, shader), result).unwrap();
113 let shader_dir = std::env::var("CARGO_MANIFEST_DIR").unwrap() + "/../webrender/res";
116 ShaderFeatureFlags::GL |
117 ShaderFeatureFlags::DUAL_SOURCE_BLENDING |
118 ShaderFeatureFlags::ADVANCED_BLEND_EQUATION |
119 ShaderFeatureFlags::DEBUG;
120 let mut shaders: Vec<String> = Vec::new();
121 for (name, features) in get_shader_features(shader_flags) {
122 shaders.extend(features.iter().map(|f| {
123 if f.is_empty() { name.to_owned() } else { format!("{} {}", name, f) }
129 // We need to ensure that the C preprocessor does not pull compiler flags from
130 // the host or target environment. Set up a SWGLPP target with empty flags to
132 if let Ok(target) = std::env::var("TARGET") {
133 if let Ok(cc) = std::env::var(format!("CC_{}", target))
134 .or(std::env::var(format!("CC_{}", target.replace("-", "_")))) {
135 std::env::set_var("CC_SWGLPP", cc);
138 std::env::set_var("CFLAGS_SWGLPP", "");
140 for shader in &shaders {
141 translate_shader(shader, &shader_dir);
144 write_load_shader(&shaders);
146 println!("cargo:rerun-if-changed=src/blend.h");
147 println!("cargo:rerun-if-changed=src/composite.h");
148 println!("cargo:rerun-if-changed=src/gl_defs.h");
149 println!("cargo:rerun-if-changed=src/glsl.h");
150 println!("cargo:rerun-if-changed=src/program.h");
151 println!("cargo:rerun-if-changed=src/rasterize.h");
152 println!("cargo:rerun-if-changed=src/swgl_ext.h");
153 println!("cargo:rerun-if-changed=src/texture.h");
154 println!("cargo:rerun-if-changed=src/vector_type.h");
155 println!("cargo:rerun-if-changed=src/gl.cc");
156 let mut build = cc::Build::new();
159 if let Ok(tool) = build.try_get_compiler() {
160 if tool.is_like_msvc() {
161 build.flag("/std:c++17")
164 .flag("/UMOZILLA_CONFIG_H");
166 build.flag("-std=c++17")
167 .flag("-fno-exceptions")
169 .flag("-fno-math-errno")
170 .flag("-UMOZILLA_CONFIG_H");
172 // SWGL relies heavily on inlining for performance so override -Oz with -O2
173 if tool.args().contains(&"-Oz".into()) {
177 // Most GLSL compilers assume something like fast-math so we turn it on.
178 // However, reciprocal division makes it so 1/1 = 0.999994 which can produce a lot of fuzz
179 // in reftests and the use of reciprocal instructions usually involves a refinement step
180 // which bloats our already bloated code. Further, our shader code is sufficiently parallel
181 // that we're more likely to be throughput bound vs latency bound. Having fewer
182 // instructions makes things easier on the processor and in places where it matters we can
183 // probably explicitly use reciprocal instructions and avoid the refinement step.
184 // Also, allow checks for non-finite values which fast-math may disable.
185 if tool.is_like_msvc() {
186 build.flag("/fp:fast")
188 .flag("-mrecip=none")
189 .flag("/clang:-fno-finite-math-only");
190 } else if tool.is_like_clang() {
191 // gcc only supports -mrecip=none on some targets so to keep
192 // things simple we don't use -ffast-math with gcc at all
193 build.flag("-ffast-math")
194 .flag("-mrecip=none")
195 .flag("-fno-finite-math-only");
199 build.file("src/gl.cc")
200 .define("_GLIBCXX_USE_CXX11_ABI", Some("0"))
203 .include(std::env::var("OUT_DIR").unwrap())