Universal approach to OpenGL error handling #550
Description
I've wrote cool macro to wrap every gl call (now works for some) to handle different OpenGL errors universally:
https://github.com/k06a/playder/blob/406ff6ea89541f79ef0cd1b452a6983d8270c2a4/src/main.rs#L12-L67
// Universal approach to OpenGL error handling
// Wrap every OpenGL call with gl_safe!(...) instead of unsafe { ... }
macro_rules! gl_safe {
(gl::CompileShader($shader:expr), $step_name:expr) => {{
let shader = $shader; // compute expression once
let result = unsafe { gl::CompileShader(shader) };
// Check for compilation errors
let mut success = gl::FALSE as gl::types::GLint;
unsafe { gl::GetShaderiv(shader, gl::COMPILE_STATUS, &mut success);}
if success != gl::TRUE as gl::types::GLint {
let mut len = 0;
unsafe { gl::GetShaderiv(shader, gl::INFO_LOG_LENGTH, &mut len); }
let mut buffer = vec![0u8; len as usize];
unsafe { gl::GetShaderInfoLog(shader, len, ptr::null_mut(), buffer.as_mut_ptr() as *mut GLchar); }
panic!("Shader compilation failed at \"{}\": {}. Check the shader source code for errors.", $step_name, str::from_utf8(&buffer).unwrap());
}
result
}};
(gl::LinkProgram($program:expr), $step_name:expr) => {{
let program = $program; // compute expression once
let result = unsafe { gl::LinkProgram($program) };
// Check for linker errors
let mut success = gl::FALSE as GLint;
gl_safe!(gl::GetProgramiv(program, gl::LINK_STATUS, &mut success), "check link status: verify program linking success");
if success != gl::TRUE as GLint {
let mut len = 0;
gl_safe!(gl::GetProgramiv(program, gl::INFO_LOG_LENGTH, &mut len), "get program info log length: determine length of linking log");
let mut buffer = vec![0u8; len as usize];
gl_safe!(gl::GetProgramInfoLog(program, len, ptr::null_mut(), buffer.as_mut_ptr() as *mut GLchar), "get program info log: retrieve linking log");
panic!("Program linking failed: {}. Verify that all shaders are correctly attached and compiled.", str::from_utf8(&buffer).unwrap());
}
result
}};
(gl::load_with($func:expr), $step_name:expr) => {{
let result = gl::load_with($func); // safe call
// Check for errors
let err_code = unsafe { gl::GetError() };
if err_code != gl::NO_ERROR {
panic!("OpenGL error code {} at \"{}\"", err_code, $step_name);
}
result
}};
($block:expr, $step_name:expr) => {{
let result = unsafe { $block };
// Check for errors
let err_code = unsafe { gl::GetError() };
if err_code != gl::NO_ERROR {
panic!("OpenGL error code {} at \"{}\"", err_code, $step_name);
}
result
}};
}