glfw: add glfw.Window.setScrollCallback

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>
This commit is contained in:
Stephen Gutekanst 2021-10-23 11:37:36 -07:00 committed by Stephen Gutekanst
parent 3d2eed7a81
commit f39a09b06e

View file

@ -46,6 +46,7 @@ pub const InternalUserPointer = struct {
setFramebufferSizeCallback: ?fn (window: Window, width: isize, height: isize) void,
setContentScaleCallback: ?fn (window: Window, xscale: f32, yscale: f32) void,
setDropCallback: ?fn (window: Window, paths: [][*c]const u8) void,
setScrollCallback: ?fn (window: Window, xoffset: f64, yoffset: f64) void,
};
/// Resets all window hints to their default values.
@ -1358,24 +1359,6 @@ pub inline fn setContentScaleCallback(self: Window, callback: ?fn (window: Windo
// /// @ingroup input
// typedef void (* GLFWcursorenterfun)(GLFWwindow*,int);
// /// The function pointer type for scroll callbacks.
// ///
// /// This is the function pointer type for scroll callbacks. A scroll callback
// /// function has the following signature:
// /// @code
// /// void function_name(GLFWwindow* window, double xoffset, double yoffset)
// /// @endcode
// ///
// /// @param[in] window The window that received the event.
// /// @param[in] xoffset The scroll offset along the x-axis.
// /// @param[in] yoffset The scroll offset along the y-axis.
// ///
// /// see also: scrolling, glfwSetScrollCallback
// /// Replaces `GLFWmousewheelfun`.
// ///
// /// @ingroup input
// typedef void (* GLFWscrollfun)(GLFWwindow*,double,double);
// /// The function pointer type for keyboard key callbacks.
// ///
// /// This is the function pointer type for keyboard key callbacks. A keyboard
@ -1850,38 +1833,42 @@ pub inline fn setContentScaleCallback(self: Window, callback: ?fn (window: Windo
// /// @ingroup input
// GLFWAPI GLFWcursorenterfun glfwSetCursorEnterCallback(GLFWwindow* window, GLFWcursorenterfun callback);
// TODO(scrolling)
// /// Sets the scroll callback.
// ///
// /// This function sets the scroll callback of the specified window, which is
// /// called when a scrolling device is used, such as a mouse wheel or scrolling
// /// area of a touchpad.
// ///
// /// The scroll callback receives all scrolling input, like that from a mouse
// /// wheel or a touchpad scrolling area.
// ///
// /// @param[in] window The window whose callback to set.
// /// @param[in] callback The new scroll callback, or null to remove the
// /// currently set callback.
// /// @return The previously set callback, or null if no callback was set or the
// /// library had not been [initialized](@ref intro_init).
// ///
// /// @callback_signature
// /// @code
// /// void function_name(GLFWwindow* window, double xoffset, double yoffset)
// /// @endcode
// /// For more information about the callback parameters, see the
// /// [function pointer type](@ref GLFWscrollfun).
// ///
// /// Possible errors include glfw.Error.NotInitialized.
// ///
// /// @thread_safety This function must only be called from the main thread.
// ///
// /// see also: scrolling
// /// Replaces `glfwSetMouseWheelCallback`.
// ///
// /// @ingroup input
// GLFWAPI GLFWscrollfun glfwSetScrollCallback(GLFWwindow* window, GLFWscrollfun callback);
fn setScrollCallbackWrapper(handle: ?*c.GLFWwindow, xoffset: f64, yoffset: f64) callconv(.C) void {
const window = from(handle.?) catch unreachable;
const internal = window.getInternal();
internal.setScrollCallback.?(window, xoffset, yoffset);
}
/// Sets the scroll callback.
///
/// This function sets the scroll callback of the specified window, which is called when a scrolling
/// device is used, such as a mouse wheel or scrolling area of a touchpad.
///
/// The scroll callback receives all scrolling input, like that from a mouse wheel or a touchpad
/// scrolling area.
///
/// @param[in] window The window whose callback to set.
/// @param[in] callback The new scroll callback, or null to remove the currently set callback.
///
/// @callback_param[in] window The window that received the event.
/// @callback_param[in] xoffset The scroll offset along the x-axis.
/// @callback_param[in] yoffset The scroll offset along the y-axis.
///
/// Possible errors include glfw.Error.NotInitialized.
///
/// @thread_safety This function must only be called from the main thread.
///
/// see also: scrolling
pub inline fn setScrollCallback(self: Window, callback: ?fn (window: Window, xoffset: f64, yoffset: f64) void) void {
var internal = self.getInternal();
internal.setScrollCallback = callback;
_ = c.glfwSetScrollCallback(self.handle, if (callback != null) setScrollCallbackWrapper else null);
// The only error this could return would be glfw.Error.NotInitialized, which should
// definitely have occurred before calls to this. Returning an error here makes the API
// awkward to use, so we discard it instead.
getError() catch {};
}
fn setDropCallbackWrapper(handle: ?*c.GLFWwindow, path_count: c_int, paths: [*c][*c]const u8) callconv(.C) void {
const window = from(handle.?) catch unreachable;
@ -2690,3 +2677,25 @@ test "setDropCallback" {
}
}).callback) catch |err| std.debug.print("can't set window drop callback, not supported by OS maybe? error={}\n", .{err});
}
test "setScrollCallback" {
const glfw = @import("main.zig");
try glfw.init();
defer glfw.terminate();
const window = glfw.Window.create(640, 480, "Hello, Zig!", null, null) catch |err| {
// return without fail, because most of our CI environments are headless / we cannot open
// windows on them.
std.debug.print("note: failed to create window: {}\n", .{err});
return;
};
defer window.destroy();
window.setScrollCallback((struct {
fn callback(_window: Window, xoffset: f64, yoffset: f64) void {
_ = _window;
_ = xoffset;
_ = yoffset;
}
}).callback);
}