egui/egui_glow/src/shader_version.rs
Emil Ernerfeldt 6f10e2e725
Improve glow error reporting (#1403)
* Improve glow error reporting
* Add more check_for_gl_error calls
* Remove clippy lint list from egui_glow lib.rs
  - Forgotten in https://github.com/emilk/egui/pull/1394
* egui_glow: move vao code to own file
* Cleanup: `use glow::HasContext as _;`

Co-authored-by: Zachary Kohnen <me@dusterthefirst.com>
2022-03-22 16:04:06 +01:00

85 lines
2.4 KiB
Rust

#![allow(unsafe_code)]
use std::convert::TryInto;
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
#[allow(dead_code)]
pub(crate) enum ShaderVersion {
Gl120,
Gl140,
Es100,
Es300,
}
impl ShaderVersion {
pub(crate) fn get(gl: &glow::Context) -> Self {
use glow::HasContext as _;
let shading_lang_string =
unsafe { gl.get_parameter_string(glow::SHADING_LANGUAGE_VERSION) };
let shader_version = Self::parse(&shading_lang_string);
tracing::debug!(
"Shader version: {:?} ({:?}).",
shader_version,
shading_lang_string
);
shader_version
}
#[inline]
pub(crate) fn parse(glsl_ver: &str) -> Self {
let start = glsl_ver.find(|c| char::is_ascii_digit(&c)).unwrap();
let es = glsl_ver[..start].contains(" ES ");
let ver = glsl_ver[start..].splitn(2, ' ').next().unwrap();
let [maj, min]: [u8; 2] = ver
.splitn(3, '.')
.take(2)
.map(|x| x.parse().unwrap_or_default())
.collect::<Vec<u8>>()
.try_into()
.unwrap();
if es {
if maj >= 3 {
Self::Es300
} else {
Self::Es100
}
} else if maj > 1 || (maj == 1 && min >= 40) {
Self::Gl140
} else {
Self::Gl120
}
}
pub(crate) fn version(&self) -> &'static str {
match self {
Self::Gl120 => "#version 120\n",
Self::Gl140 => "#version 140\n",
Self::Es100 => "#version 100\n",
Self::Es300 => "#version 300 es\n",
}
}
pub(crate) fn is_new_shader_interface(&self) -> &'static str {
match self {
ShaderVersion::Es300 | ShaderVersion::Gl140 => "#define NEW_SHADER_INTERFACE\n",
_ => "",
}
}
}
#[test]
fn test_shader_version() {
use ShaderVersion::{Es100, Es300, Gl120, Gl140};
for (s, v) in [
("1.2 OpenGL foo bar", Gl120),
("3.0", Gl140),
("0.0", Gl120),
("OpenGL ES GLSL 3.00 (WebGL2)", Es300),
("OpenGL ES GLSL 1.00 (WebGL)", Es100),
("OpenGL ES GLSL ES 1.00 foo bar", Es100),
("WebGL GLSL ES 3.00 foo bar", Es300),
("WebGL GLSL ES 3.00", Es300),
("WebGL GLSL ES 1.0 foo bar", Es100),
] {
assert_eq!(ShaderVersion::parse(s), v);
}
}