Got initial unsafe bindings working. See comments.

- This now builds the bindings (still with cbindgen in build.rs,
  will change that in a bit) and links to them successfully. Everything
  currently points to the master branch at Gekkio/imgui-rs, because
  there has not been a release yet with the PR merged that exposes
  the defines in the sys crate.

- I have now included a little demo crate that calls into the unsafe
  generated bindings as a proof of concept. Next there will need to
  be safe and more Rust-y bindings written around this, just like
  imgui-rs has them.

implot-sys/Cargo.toml

@@ -7,6 +7,7 @@ description = "Raw FFI bindings to implot"
 license = "MIT/Apache-2.0"
 categories = ["gui", "external-ffi-bindings"]
 build = "build.rs"
+links = "implot"
 
 [dependencies]
 imgui-sys = { git = "https://github.com/Gekkio/imgui-rs/", branch = "master" }

implot-sys/build.rs

@@ -5,7 +5,7 @@
 // for now, but expected to diverge from that over time.
 use std::{env, fs, io, path::Path};
 
-//use bindgen; // Not used anymore, TODO(4bb4) remove
+use bindgen;
 
 const CPP_FILES: [&str; 2] = [
     "third-party/cimplot/cimplot.cpp",
@@ -45,8 +45,8 @@ fn main() -> io::Result<()> {
     let cimgui_include_path =
         env::var_os("DEP_IMGUI_THIRD_PARTY").expect("DEP_IMGUI_THIRD_PARTY not defined");
     let imgui_include_path = Path::new(&cimgui_include_path).join("imgui");
-    build.include(cimgui_include_path);
-    build.include(imgui_include_path);
+    build.include(&cimgui_include_path);
+    build.include(&imgui_include_path);
 
     // Taken from the imgui-sys build as well
     build.flag_if_supported("-Wno-return-type-c-linkage");
@@ -58,21 +58,20 @@ fn main() -> io::Result<()> {
     build.compile("cimplot");
 
     // --- Create bindgen bindings
-    // TODO(4bb4) move this out to separate shell script (see #1)
-    // The actual generate() errors out right now with parsing errors,
-    // will probably need to whiltelist things, fix preprocessor definitions,
-    // bindgen settings or some combination thereof.
-    //let _bindings = bindgen::Builder::default()
-    //.header(imgui_third_party.into_string().unwrap() + "/cimgui.h")
-    //.header("wrapper.h")
-    //.parse_callbacks(Box::new(bindgen::CargoCallbacks));
-    //.generate()
-    //.expect("Unable to generate bindings");
+    // TODO(4bb4) move this out to separate shell script (see #1) so users don't have
+    // to have clang installed to build this crate.
+    let bindings = bindgen::Builder::default()
+        .header(&(cimgui_include_path.into_string().unwrap() + "/cimgui.h"))
+        .header("third-party/cimplot/cimplot.h")
+        .parse_callbacks(Box::new(bindgen::CargoCallbacks))
+        .clang_arg("-DCIMGUI_DEFINE_ENUMS_AND_STRUCTS=1")
+        .generate()
+        .expect("Unable to generate bindings");
 
-    //let out_path = std::path::PathBuf::from(env::var("OUT_DIR").unwrap());
-    //bindings
-    //.write_to_file(out_path.join("bindings.rs"))
-    //.expect("Couldn't write bindings!");
+    let out_path = std::path::PathBuf::from(env::var("OUT_DIR").unwrap());
+    bindings
+        .write_to_file(out_path.join("bindings.rs"))
+        .expect("Couldn't write bindings!");
 
     Ok(())
 }

implot-sys/src/lib.rs

@@ -1,3 +1,7 @@
-fn _does_nothing() {
-    println!("This does nothing yet");
-}
+#![allow(non_upper_case_globals)]
+#![allow(non_camel_case_types)]
+#![allow(non_snake_case)]
+
+// TODO(4bb4) change this to include the bindings we hand-generate
+// once that is happening
+include!(concat!(env!("OUT_DIR"), "/bindings.rs"));

testexample/Cargo.toml

@@ -0,0 +1,21 @@
+[package]
+name = "imgui-examples"
+version = "0.0.0"
+edition = "2018"
+authors = ["Joonas Javanainen <joonas.javanainen@gmail.com>", "imgui-rs contributors"]
+description = "imgui crate examples using Glium backend"
+homepage = "https://github.com/Gekkio/imgui-rs"
+repository = "https://github.com/Gekkio/imgui-rs"
+license = "MIT/Apache-2.0"
+publish = false
+
+[dependencies]
+clipboard = "0.5"
+glium = { version = "0.27", default-features = true }
+image = "0.23"
+imgui-sys = { git = "https://github.com/Gekkio/imgui-rs/", branch = "master" }
+imgui = { git = "https://github.com/Gekkio/imgui-rs/", branch = "master" }
+imgui-glium-renderer = { git = "https://github.com/Gekkio/imgui-rs/", branch = "master" }
+imgui-winit-support = { git = "https://github.com/Gekkio/imgui-rs/", branch = "master" }
+
+implot-sys = { path = "../implot-sys" }

testexample/src/main.rs

@@ -0,0 +1,67 @@
+use imgui::*;
+use implot_sys;
+
+mod support;
+
+fn main() {
+    let system = support::init(file!());
+    system.main_loop(move |_, ui| {
+        Window::new(im_str!("Hello world"))
+            .size([300.0, 110.0], Condition::FirstUseEver)
+            .build(ui, || {
+                ui.text(im_str!("Hello world!"));
+                ui.text(im_str!("こんにちは世界！"));
+                ui.text(im_str!("This...is...imgui-rs!"));
+                ui.separator();
+                let mouse_pos = ui.io().mouse_pos;
+                ui.text(format!(
+                    "Mouse Position: ({:.1},{:.1})",
+                    mouse_pos[0], mouse_pos[1]
+                ));
+
+                // TODO(4bb4) Replace this with safe bindings once those are written
+
+                let x_values: [f64; 4] = [1.0, 2.0, 4.0, 5.0];
+                let y_values: [f64; 4] = [1.0, 0.0, 0.0, 1.0];
+                unsafe {
+                    if implot_sys::ImPlot_BeginPlot(
+                        im_str!("My Plot").as_ptr() as *const i8,
+                        im_str!("x").as_ptr() as *const i8,
+                        im_str!("y").as_ptr() as *const i8,
+                        implot_sys::ImVec2 { x: 600.0, y: 600.0 },
+                        0xFF,
+                        7,
+                        7,
+                        0,
+                        0,
+                    ) {
+                        implot_sys::ImPlot_PlotLinedoublePtrdoublePtr(
+                            im_str!("Mouth").as_ptr() as *const i8,
+                            x_values.as_ptr(),
+                            y_values.as_ptr(),
+                            x_values.len() as i32,
+                            0,
+                            8,
+                        );
+                        implot_sys::ImPlot_PlotLinedoublePtrdoublePtr(
+                            im_str!("Left eye").as_ptr() as *const i8,
+                            [2.0, 2.0].as_ptr(),
+                            [2.0, 1.0].as_ptr(),
+                            2i32,
+                            0,
+                            8,
+                        );
+                        implot_sys::ImPlot_PlotLinedoublePtrdoublePtr(
+                            im_str!("Right eye").as_ptr() as *const i8,
+                            [4.0, 4.0].as_ptr(),
+                            [2.0, 1.0].as_ptr(),
+                            2i32,
+                            0,
+                            8,
+                        );
+                        implot_sys::ImPlot_EndPlot();
+                    }
+                }
+            });
+    });
+}

testexample/src/support/clipboard.rs

@@ -0,0 +1,24 @@
+// Taken directly from imgui-rs examples at
+//
+//   https://github.com/Gekkio/imgui-rs/tree/master/imgui-examples/examples/support
+//
+// Not my code. Originally by Joonas Javanainen and the ImGUI-rs contributors
+use clipboard::{ClipboardContext, ClipboardProvider};
+use imgui::{ClipboardBackend, ImStr, ImString};
+
+pub struct ClipboardSupport(ClipboardContext);
+
+pub fn init() -> Option<ClipboardSupport> {
+    ClipboardContext::new()
+        .ok()
+        .map(|ctx| ClipboardSupport(ctx))
+}
+
+impl ClipboardBackend for ClipboardSupport {
+    fn get(&mut self) -> Option<ImString> {
+        self.0.get_contents().ok().map(|text| text.into())
+    }
+    fn set(&mut self, text: &ImStr) {
+        let _ = self.0.set_contents(text.to_str().to_owned());
+    }
+}

testexample/src/support/mod.rs

@@ -0,0 +1,133 @@
+// Taken directly from imgui-rs examples at
+//
+//   https://github.com/Gekkio/imgui-rs/tree/master/imgui-examples/examples/support
+//
+// Not my code. Originally by Joonas Javanainen and the ImGUI-rs contributors
+use glium::glutin;
+use glium::glutin::event::{Event, WindowEvent};
+use glium::glutin::event_loop::{ControlFlow, EventLoop};
+use glium::glutin::window::WindowBuilder;
+use glium::{Display, Surface};
+use imgui::{Context, FontConfig, FontGlyphRanges, FontSource, Ui};
+use imgui_glium_renderer::Renderer;
+use imgui_winit_support::{HiDpiMode, WinitPlatform};
+use std::time::Instant;
+
+mod clipboard;
+
+pub struct System {
+    pub event_loop: EventLoop<()>,
+    pub display: glium::Display,
+    pub imgui: Context,
+    pub platform: WinitPlatform,
+    pub renderer: Renderer,
+    pub font_size: f32,
+}
+
+pub fn init(title: &str) -> System {
+    let title = match title.rfind('/') {
+        Some(idx) => title.split_at(idx + 1).1,
+        None => title,
+    };
+    let event_loop = EventLoop::new();
+    let context = glutin::ContextBuilder::new().with_vsync(true);
+    let builder = WindowBuilder::new()
+        .with_title(title.to_owned())
+        .with_inner_size(glutin::dpi::LogicalSize::new(1024f64, 768f64));
+    let display =
+        Display::new(builder, context, &event_loop).expect("Failed to initialize display");
+
+    let mut imgui = Context::create();
+    imgui.set_ini_filename(None);
+
+    if let Some(backend) = clipboard::init() {
+        imgui.set_clipboard_backend(Box::new(backend));
+    } else {
+        eprintln!("Failed to initialize clipboard");
+    }
+
+    let mut platform = WinitPlatform::init(&mut imgui);
+    {
+        let gl_window = display.gl_window();
+        let window = gl_window.window();
+        platform.attach_window(imgui.io_mut(), &window, HiDpiMode::Rounded);
+    }
+
+    let hidpi_factor = platform.hidpi_factor();
+    let font_size = (13.0 * hidpi_factor) as f32;
+    imgui.fonts().add_font(&[FontSource::DefaultFontData {
+        config: Some(FontConfig {
+            size_pixels: font_size,
+            ..FontConfig::default()
+        }),
+    }]);
+
+    imgui.io_mut().font_global_scale = (1.0 / hidpi_factor) as f32;
+
+    let renderer = Renderer::init(&mut imgui, &display).expect("Failed to initialize renderer");
+
+    System {
+        event_loop,
+        display,
+        imgui,
+        platform,
+        renderer,
+        font_size,
+    }
+}
+
+impl System {
+    pub fn main_loop<F: FnMut(&mut bool, &mut Ui) + 'static>(self, mut run_ui: F) {
+        let System {
+            event_loop,
+            display,
+            mut imgui,
+            mut platform,
+            mut renderer,
+            ..
+        } = self;
+        let mut last_frame = Instant::now();
+
+        event_loop.run(move |event, _, control_flow| match event {
+            Event::NewEvents(_) => {
+                let now = Instant::now();
+                imgui.io_mut().update_delta_time(now - last_frame);
+                last_frame = now;
+            }
+            Event::MainEventsCleared => {
+                let gl_window = display.gl_window();
+                platform
+                    .prepare_frame(imgui.io_mut(), &gl_window.window())
+                    .expect("Failed to prepare frame");
+                gl_window.window().request_redraw();
+            }
+            Event::RedrawRequested(_) => {
+                let mut ui = imgui.frame();
+
+                let mut run = true;
+                run_ui(&mut run, &mut ui);
+                if !run {
+                    *control_flow = ControlFlow::Exit;
+                }
+
+                let gl_window = display.gl_window();
+                let mut target = display.draw();
+                target.clear_color_srgb(1.0, 1.0, 1.0, 1.0);
+                platform.prepare_render(&ui, gl_window.window());
+                let draw_data = ui.render();
+                renderer
+                    .render(&mut target, draw_data)
+                    .expect("Rendering failed");
+                target.finish().expect("Failed to swap buffers");
+            }
+            Event::WindowEvent {
+                event: WindowEvent::CloseRequested,
+                ..
+            } => *control_flow = ControlFlow::Exit,
+            event => {
+                let gl_window = display.gl_window();
+                platform.handle_event(imgui.io_mut(), gl_window.window(), &event);
+            }
+        })
+    }
+}