feat: add GLFW wrapper library

1 files changed, 128 insertions, 0 deletions

diff --git a/glfw/src/window.rs b/glfw/src/window.rs
new file mode 100644
index 0000000..6f5c845
--- /dev/null
+++ b/glfw/src/window.rs
@@ -0,0 +1,128 @@
+use std::ffi::{CStr, CString};
+use std::ptr::null_mut;
+
+use crate::init::{initialize, Glfw};
+use crate::{get_glfw_error, Error};
+
+pub struct Window
+{
+    _init: Glfw,
+    handle: *mut crate::ffi::GLFWwindow,
+}
+
+impl Window
+{
+    /// Creates a new window.
+    ///
+    /// # Errors
+    /// Will return `Err` if
+    /// - The title contains an internal nul byte
+    /// - A GLFW error occurs
+    pub fn create(size: &Size, title: &str) -> Result<Self, Error>
+    {
+        let init = initialize()?;
+
+        let c_title =
+            CString::new(title).map_err(|_| Error::InternalNulByteInWindowTitle)?;
+
+        // SAFETY: The initialize function makes sure the current thread is the main
+        // thread
+        let handle = unsafe {
+            #[allow(clippy::cast_possible_wrap)]
+            crate::ffi::glfwCreateWindow(
+                size.width as i32,
+                size.height as i32,
+                c_title.as_ptr(),
+                null_mut(),
+                null_mut(),
+            )
+        };
+
+        get_glfw_error()?;
+
+        Ok(Self {
+            _init: init,
+            handle,
+        })
+    }
+
+    /// Makes the context of the window current for the calling thread.
+    ///
+    /// # Errors
+    /// Will return `Err` if a GLFW platform error occurs or if no OpenGL context is
+    /// present.
+    pub fn make_context_current(&self) -> Result<(), Error>
+    {
+        unsafe { crate::ffi::glfwMakeContextCurrent(self.handle) };
+
+        get_glfw_error()?;
+
+        Ok(())
+    }
+
+    /// Returns the address of the specified OpenGL function, if it is supported by the
+    /// current context.
+    ///
+    /// # Errors
+    /// Will return `Err` if a GLFW platform error occurs or if no current context has
+    /// been set.
+    pub fn get_proc_address(
+        &self,
+        proc_name: &CStr,
+    ) -> Result<unsafe extern "C" fn(), Error>
+    {
+        let proc_addr = unsafe { crate::ffi::glfwGetProcAddress(proc_name.as_ptr()) };
+
+        get_glfw_error()?;
+
+        // SAFETY: Is only None when a error has occured and that case is handled above
+        Ok(unsafe { proc_addr.unwrap_unchecked() })
+    }
+
+    /// Processes all pending events.
+    ///
+    /// # Errors
+    /// Will return `Err` if a GLFW platform error occurs.
+    pub fn poll_events(&self) -> Result<(), Error>
+    {
+        // SAFETY: The initialize function (called when the window is created) makes sure
+        // the current thread is the main thread
+        unsafe { crate::ffi::glfwPollEvents() };
+
+        get_glfw_error()?;
+
+        Ok(())
+    }
+
+    /// Swaps the front and back buffers of the window.
+    ///
+    /// # Errors
+    /// Will return `Err` if a GLFW platform error occurs or if no OpenGL window context
+    /// is present.
+    pub fn swap_buffers(&self) -> Result<(), Error>
+    {
+        unsafe {
+            crate::ffi::glfwSwapBuffers(self.handle);
+        };
+
+        get_glfw_error()?;
+
+        Ok(())
+    }
+
+    /// Returns whether or not the window should close.
+    #[must_use]
+    pub fn should_close(&self) -> bool
+    {
+        let should_close = unsafe { crate::ffi::glfwWindowShouldClose(self.handle) };
+
+        should_close == crate::ffi::GLFW_TRUE
+    }
+}
+
+/// Window size.
+pub struct Size
+{
+    pub width: u32,
+    pub height: u32,
+}