Skip to content

Commit

Permalink
Replace clap with structops
Browse files Browse the repository at this point in the history
  • Loading branch information
@k06a
k06a committed Feb 4, 2025
1 parent 2093546 commit e90d705
Show file tree
Hide file tree
Showing 3 changed files with 162 additions and 59 deletions.
130 changes: 126 additions & 4 deletions Cargo.lock
View file

Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.

2 changes: 2 additions & 0 deletions Cargo.toml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -7,3 +7,5 @@ edition = "2021"
clap = "3.0"
gl = "0.14.0"
glutin = "0.28.0"
structopt = "0.3"
structopt-derive = "0.4"
89 changes: 34 additions & 55 deletions src/main.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -5,40 +5,40 @@ use std::str;
use glutin::window::WindowBuilder;
use glutin::ContextBuilder;
use std::io::{self, Write};
use clap::{App, Arg};
use structopt::StructOpt;

// Universal approach to OpenGL error handling
// Wrap every all into gl_safe!(...) instead of unsafe { ... }
// 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) };
(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($shader, gl::COMPILE_STATUS, &mut success);}
unsafe { gl::GetShaderiv(shader, gl::COMPILE_STATUS, &mut success);}
if success != gl::TRUE as gl::types::GLint {
let mut len = 0;
unsafe { gl::GetShaderiv($shader, gl::INFO_LOG_LENGTH, &mut len); }
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); }
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 $program = _program; // compute expression once
(gl::LinkProgram($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($program, gl::LINK_STATUS, &mut success), "check link status: verify program linking success");
gl_safe!(gl::GetProgramiv(program, gl::LINK_STATUS, &mut success), "check link status: verify program linking success");
if success != gl::TRUE as GLint {
let mut len = 0;
gl_safe!(gl::GetProgramiv($program, gl::INFO_LOG_LENGTH, &mut len), "get program info log length: determine length of linking log");
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");
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());
}
Expand Down Expand Up @@ -74,39 +74,18 @@ fn compile_shader(src: &str, ty: GLenum) -> GLuint {
shader
}

#[derive(StructOpt, Debug)]
#[structopt(name = "Shader Renderer", about = "Renders a fragment shader to a video file")]
struct Opt {
shader_path: String,
width: u32,
height: u32,
fps: u32,
duration: u32,
}

fn main() {
// Parse command line arguments
let matches = App::new("Shader Renderer")
.version("1.0")
.author("Anton Bukov <k06aaa@gmail.com>")
.about("Renders a shader to a video file")
.arg(Arg::new("shader")
.help("Path to the shader file")
.required(true)
.index(1))
.arg(Arg::new("width")
.help("Width of the video")
.required(true)
.index(2))
.arg(Arg::new("height")
.help("Height of the video")
.required(true)
.index(3))
.arg(Arg::new("fps")
.help("Frames per second")
.required(true)
.index(4))
.arg(Arg::new("duration")
.help("Duration of the video in seconds")
.required(true)
.index(5))
.get_matches();

let shader_path = matches.value_of("shader").unwrap();
let width: u32 = matches.value_of("width").unwrap().parse().expect("Invalid width");
let height: u32 = matches.value_of("height").unwrap().parse().expect("Invalid height");
let fps: u32 = matches.value_of("fps").unwrap().parse().expect("Invalid fps");
let duration: u32 = matches.value_of("duration").unwrap().parse().expect("Invalid duration");
let opt = Opt::from_args();

// Create an invisible OpenGL context
let el = glutin::event_loop::EventLoop::new();
Expand All @@ -125,7 +104,7 @@ fn main() {
let vs = compile_shader(vertex_shader_src, gl::VERTEX_SHADER);

// Load and compile fragment shader source from file
let fs_src = std::fs::read_to_string(shader_path).expect("Failed to read shader file");
let fs_src = std::fs::read_to_string(&opt.shader_path).expect("Failed to read shader file");
let fs = compile_shader(&fs_src, gl::FRAGMENT_SHADER);

// Create a program and attach the fragment shader
Expand All @@ -144,7 +123,7 @@ fn main() {
let mut texture = 0;
gl_safe!(gl::GenTextures(1, &mut texture), "generate texture: create a new texture object");
gl_safe!(gl::BindTexture(gl::TEXTURE_2D, texture), "bind texture: set the texture as active");
gl_safe!(gl::TexImage2D(gl::TEXTURE_2D, 0, gl::RGB as i32, width as i32, height as i32, 0, gl::RGB, gl::UNSIGNED_BYTE, ptr::null()), "create texture image: allocate storage for texture");
gl_safe!(gl::TexImage2D(gl::TEXTURE_2D, 0, gl::RGB as i32, opt.width as i32, opt.height as i32, 0, gl::RGB, gl::UNSIGNED_BYTE, ptr::null()), "create texture image: allocate storage for texture");
gl_safe!(gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MIN_FILTER, gl::LINEAR as i32), "set texture min filter: define texture minification filter");
gl_safe!(gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MAG_FILTER, gl::LINEAR as i32), "set texture mag filter: define texture magnification filter");
gl_safe!(gl::FramebufferTexture2D(gl::FRAMEBUFFER, gl::COLOR_ATTACHMENT0, gl::TEXTURE_2D, texture, 0), "attach texture to framebuffer: link texture to framebuffer");
Expand All @@ -160,7 +139,7 @@ fn main() {
if i_resolution_loc == -1 {
panic!("Failed to get uniform location for iResolution. Ensure the uniform variable is declared in the shader.");
}
gl_safe!(gl::Uniform3f(i_resolution_loc, width as f32, height as f32, 0.0), "set iResolution uniform: set uniform value");
gl_safe!(gl::Uniform3f(i_resolution_loc, opt.width as f32, opt.height as f32, 0.0), "set iResolution uniform: set uniform value");

// Get iTime uniform location to use inside of the render loop
let i_time_cstr = CString::new("iTime").unwrap();
Expand Down Expand Up @@ -188,27 +167,27 @@ fn main() {
gl_safe!(gl::VertexAttribPointer(0, 3, gl::FLOAT, gl::FALSE, 3 * std::mem::size_of::<f32>() as GLsizei, ptr::null()), "setting vertex attrib pointer");
gl_safe!(gl::EnableVertexAttribArray(0), "enabling vertex attrib array");

// Create a vector for pixels once before the loop
let mut pixels = vec![0u8; (width * height * 3) as usize];

// Set viewport and clear color
gl_safe!(gl::Viewport(0, 0, width as i32, height as i32), "setting viewport");
gl_safe!(gl::Viewport(0, 0, opt.width as i32, opt.height as i32), "setting viewport");
gl_safe!(gl::ClearColor(0.0, 0.0, 0.0, 1.0), "setting clear color");
gl_safe!(gl::Clear(gl::COLOR_BUFFER_BIT), "clearing framebuffer");

// Bind vertex array
gl_safe!(gl::BindVertexArray(vao), "binding vertex array");

// Create a vector for pixels once before the loop
let mut pixels = vec![0u8; (opt.width * opt.height * 3) as usize];

// Main rendering loop
for frame in 0..(fps * duration) {
for frame in 0..(opt.fps * opt.duration) {
// Set iTime uniform
gl_safe!(gl::Uniform1f(i_time_loc, frame as f32 / fps as f32), "setting uniform value for iTime");
gl_safe!(gl::Uniform1f(i_time_loc, frame as f32 / opt.fps as f32), "setting uniform value for iTime");

// Render the rectangle
gl_safe!(gl::DrawArrays(gl::TRIANGLE_FAN, 0, 4), "drawing arrays");

// Read pixels from the framebuffer
gl_safe!(gl::ReadPixels(0, 0, width as i32, height as i32, gl::RGB, gl::UNSIGNED_BYTE, pixels.as_mut_ptr() as *mut _), "reading pixels");
gl_safe!(gl::ReadPixels(0, 0, opt.width as i32, opt.height as i32, gl::RGB, gl::UNSIGNED_BYTE, pixels.as_mut_ptr() as *mut _), "reading pixels");

// Write pixels to stdout
io::stdout().write_all(&pixels).unwrap();
Expand Down

0 comments on commit e90d705

Please sign in to comment.