glfw: add Window.hint

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

glfw/src/Window.zig

@@ -22,6 +22,31 @@ pub fn defaultHints() Error!void {
     try getError();
 }
 
+/// Sets the specified window hint to the desired value.
+///
+/// This function sets hints for the next call to glfw.Window.create. The hints, once set, retain
+/// their values until changed by a call to this function or glfw.window.defaultHints, or until the
+/// library is terminated.
+///
+/// Only integer value hints can be set with this function. String value hints are set with
+/// glfw.Window.hintString.
+///
+/// This function does not check whether the specified hint values are valid. If you set hints to
+/// invalid values this will instead be reported by the next call to glfw.createWindow.
+///
+/// Some hints are platform specific. These may be set on any platform but they will only affect
+/// their specific platform. Other platforms will ignore them.
+///
+/// Possible errors include glfw.Error.NotInitialized and glfw.Error.InvalidEnum.
+///
+/// @thread_safety This function must only be called from the main thread.
+///
+/// see also: window_hints, glfw.Window.hintString, glfw.Window.defaultHints
+pub fn hint(hint_const: usize, value: isize) Error!void {
+    c.glfwWindowHint(@intCast(c_int, hint_const), @intCast(c_int, value));
+    try getError();
+}
+
 test "defaultHints" {
     const glfw = @import("main.zig");
     try glfw.init();
@@ -29,3 +54,12 @@ test "defaultHints" {
 
     try defaultHints();
 }
+
+test "hint" {
+    const glfw = @import("main.zig");
+    try glfw.init();
+    defer glfw.terminate();
+
+    try hint(glfw.focused, 1);
+    try defaultHints();
+}