rename input callback to something more appropriate.

src/io/input.c

@@ -4,7 +4,7 @@
 
 #include <GLFW/glfw3.h>
 
-void key_callback(GLFWwindow *win, int key, int scancode, int action, int mods) {
+void input_callback(GLFWwindow *win, int key, int scancode, int action, int mods) {
 	(void)win, (void)key, (void)scancode, (void)action, (void)mods; // make the compiler shut up as this is fine
 #ifndef NDEBUG
 	if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)

src/io/input.h

@@ -4,4 +4,6 @@
 
 #include <GLFW/glfw3.h>
 
-void key_callback(GLFWwindow *win, int key, int scancode, int action, int mods);
+/* Handles incoming key inputs for `win`.
+ * Intended to be given as an argument to `glfwSetKeyCallback`. */
+void input_callback(GLFWwindow *win, int key, int scancode, int action, int mods);

src/io/window.c

@@ -41,8 +41,7 @@ int window_init(void) {
 	if (!gladLoadGL(glfwGetProcAddress)) return 1;
 	glfwSwapInterval(1); // wait 1 screen update for a redraw a.k.a. "vsync". (not really applicable in this case but eh)
 
-	// configure callbacks
-	glfwSetKeyCallback(win, key_callback);
+	glfwSetKeyCallback(win, input_callback);
 
 	// print the OpenGL version information
 	debug(