pub fn from_file<P>(path: P) -> Result<ShaderPrototype, ShaderError> where P: AsRef<Path> {
        let mut vert_src = String::new();
        let mut frag_src = String::new();
        let mut geom_src = String::new();

        enum Target { Vert, Frag, Geom }
        let mut current = None;

        let file = File::open(path)?;
        let reader = BufReader::new(file);
        for line in reader.lines() {
            let line = line?;
            let line = line.trim();

            if line.starts_with("--") {
                let value = line[2..].trim();
                match value {
                    "VERT" => current = Some(Target::Vert),
                    "FRAG" => current = Some(Target::Frag),
                    "GEOM" => current = Some(Target::Geom),
                    _ => {
                        let message = format!("Expected 'VERT', 'FRAG' or 'GEOM', found {}", &line[2..]);
                        return Err(ShaderError::FileFormat(message));
                    }
                }
            } else {
                match current {
                    Some(Target::Vert) => {
                        vert_src.push_str(line);
                        vert_src.push('\n');
                    },
                    Some(Target::Frag) => {
                        frag_src.push_str(line);
                        frag_src.push('\n');
                    },
                    Some(Target::Geom) => {
                        geom_src.push_str(line);
                        geom_src.push('\n');
                    },
                    None => (),
                }
            }
        }

        Ok(ShaderPrototype {
            vert_src,
            geom_src,
            frag_src,
            transform_feedback_outputs: None,
        })
    }
/// Loads a shader from a file. The file should contain all the shader stages, with
/// each shader stage prepended by `-- name`, where name is one of `VERT`, `FRAG`
/// or `GEOM`.
/// # Example file
/// ```glsl
/// -- VERT
/// in vec2 position;
/// void main() {
///     gl_Position = vec4(position, 0.0, 1.0);
/// }
/// -- FRAG
/// out vec4 color;
/// void main() {
///     color = vec4(1.0, 0.0, 0.0, 1.0); // Draw in red
/// }
/// ```
Loads a shader from a file.
Loads a shader from a file .
pub fn from_file<P>(path: P) -> Result<ShaderPrototype, ShaderError> where P: AsRef<Path> {
        let mut vert_src = String::new();
        let mut frag_src = String::new();
        let mut geom_src = String::new();
        enum Target { Vert, Frag, Geom }
        let mut current = None;
        let file = File::open(path)?;
        let reader = BufReader::new(file);
        for line in reader.lines() {
            let line = line?;
            let line = line.trim();
            if line.starts_with("--") {
                let value = line[2..].trim();
                match value {
                    "VERT" => current = Some(Target::Vert),
                    "FRAG" => current = Some(Target::Frag),
                    "GEOM" => current = Some(Target::Geom),
                    _ => {
                        let message = format!("Expected 'VERT', 'FRAG' or 'GEOM', found {}", &line[2..]);
                        return Err(ShaderError::FileFormat(message));
                    }
                }
            } else {
                match current {
                    Some(Target::Vert) => {
                        vert_src.push_str(line);
                        vert_src.push('\n');
                    },
                    Some(Target::Frag) => {
                        frag_src.push_str(line);
                        frag_src.push('\n');
                    },
                    Some(Target::Geom) => {
                        geom_src.push_str(line);
                        geom_src.push('\n');
                    },
                    None => (),
                }
            }
        }
        Ok(ShaderPrototype {
            vert_src,
            geom_src,
            frag_src,
            transform_feedback_outputs: None,
        })
    }
pub fn from_file < P > ( path : P ) -> Result < ShaderPrototype , ShaderError > where P : AsRef < Path > { let mut vert_src = String :: new ( ) ; let mut frag_src = String :: new ( ) ; let mut geom_src = String :: new ( ) ; enum Target { Vert , Frag , Geom } let mut current = None ; let file = File :: open ( path ) ? ; let reader = BufReader :: new ( file ) ; for line in reader . lines ( ) { let line = line ? ; let line = line . trim ( ) ; if line . starts_with ( " " ) { let value = line [ 2 .. ] . trim ( ) ; match value { " " => current = Some ( Target :: Vert ) , " " => current = Some ( Target :: Frag ) , " " => current = Some ( Target :: Geom ) , _ => { let message = format ! ( " " line [ 2 ] ) ; return Err ( ShaderError :: FileFormat ( message ) ) ; } } } else { match current { Some ( Target :: Vert ) => { vert_src . push_str ( line ) ; vert_src . push ( '\n' ) ; } , Some ( Target :: Frag ) => { frag_src . push_str ( line ) ; frag_src . push ( '\n' ) ; } , Some ( Target :: Geom ) => { geom_src . push_str ( line ) ; geom_src . push ( '\n' ) ; } , None => ( ) , } } } Ok ( ShaderPrototype { vert_src , geom_src , frag_src , transform_feedback_outputs : None , } ) }
Loads a shader from a file.
Loads a shader from a file .
path
P
path
P
example file
None