From 509e7f3b4ba557c2c9c7c7a7a74651a5e767851f Mon Sep 17 00:00:00 2001
From: Stephen Gutekanst <stephen@hexops.com>
Date: Fri, 22 Oct 2021 00:00:46 -0700
Subject: [PATCH] glfw: add Cursor.create

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>
---
 glfw/src/Cursor.zig | 100 +++++++++++++++++++++++++-------------------
 1 file changed, 57 insertions(+), 43 deletions(-)

diff --git a/glfw/src/Cursor.zig b/glfw/src/Cursor.zig
index f890753f..861b56e1 100644
--- a/glfw/src/Cursor.zig
+++ b/glfw/src/Cursor.zig
@@ -1,47 +1,48 @@
-// TODO(cursor):
-// /// Opaque cursor object.
-// ///
-// /// Opaque cursor object.
-// ///
-// /// see also: cursor_object
-// ///
-// ///
-// /// @ingroup input
-// typedef struct GLFWcursor GLFWcursor;
+//! Represents a cursor and provides facilities for setting cursor images.
 
-// TODO(cursor icon)
-// /// Creates a custom cursor.
-// ///
-// /// Creates a new custom cursor image that can be set for a window with @ref
-// /// glfwSetCursor. The cursor can be destroyed with @ref glfwDestroyCursor.
-// /// Any remaining cursors are destroyed by @ref glfwTerminate.
-// ///
-// /// The pixels are 32-bit, little-endian, non-premultiplied RGBA, i.e. eight
-// /// bits per channel with the red channel first. They are arranged canonically
-// /// as packed sequential rows, starting from the top-left corner.
-// ///
-// /// The cursor hotspot is specified in pixels, relative to the upper-left corner
-// /// of the cursor image. Like all other coordinate systems in GLFW, the X-axis
-// /// points to the right and the Y-axis points down.
-// ///
-// /// @param[in] image The desired cursor image.
-// /// @param[in] xhot The desired x-coordinate, in pixels, of the cursor hotspot.
-// /// @param[in] yhot The desired y-coordinate, in pixels, of the cursor hotspot.
-// /// @return The handle of the created cursor, or null if an
-// /// error occurred.
-// ///
-// /// Possible errors include glfw.Error.NotInitialized and glfw.Error.PlatformError.
-// ///
-// /// @pointer_lifetime The specified image data is copied before this function
-// /// returns.
-// ///
-// /// @thread_safety This function must only be called from the main thread.
-// ///
-// /// see also: cursor_object, glfwDestroyCursor, glfwCreateStandardCursor
-// ///
-// ///
-// /// @ingroup input
-// GLFWAPI GLFWcursor* glfwCreateCursor(const GLFWimage* image, int xhot, int yhot);
+const std = @import("std");
+const testing = std.testing;
+
+const c = @import("c.zig").c;
+const Error = @import("errors.zig").Error;
+const getError = @import("errors.zig").getError;
+const Image = @import("Image.zig");
+
+const Cursor = @This();
+
+ptr: *c.GLFWcursor,
+
+/// Creates a custom cursor.
+///
+/// Creates a new custom cursor image that can be set for a window with glfw.Cursor.set. The cursor
+/// can be destroyed with glfwCursor.destroy. Any remaining cursors are destroyed by glfw.terminate.
+///
+/// The pixels are 32-bit, little-endian, non-premultiplied RGBA, i.e. eight bits per channel with
+/// the red channel first. They are arranged canonically as packed sequential rows, starting from
+/// the top-left corner.
+///
+/// The cursor hotspot is specified in pixels, relative to the upper-left corner of the cursor
+/// image. Like all other coordinate systems in GLFW, the X-axis points to the right and the Y-axis
+/// points down.
+///
+/// @param[in] image The desired cursor image.
+/// @param[in] xhot The desired x-coordinate, in pixels, of the cursor hotspot.
+/// @param[in] yhot The desired y-coordinate, in pixels, of the cursor hotspot.
+/// @return The handle of the created cursor.
+///
+/// Possible errors include glfw.Error.NotInitialized and glfw.Error.PlatformError.
+///
+/// @pointer_lifetime The specified image data is copied before this function returns.
+///
+/// @thread_safety This function must only be called from the main thread.
+///
+/// see also: cursor_object, glfw.Cursor.destroy, glfw.Cursor.createStandard
+pub inline fn create(image: Image, xhot: isize, yhot: isize) Error!Cursor {
+    const img = image.toC();
+    const cursor = c.glfwCreateCursor(&img, @intCast(c_int, xhot), @intCast(c_int, yhot));
+    try getError();
+    return Cursor{ .ptr = cursor.? };
+}
 
 // TODO(cursor icon)
 // /// Creates a cursor with a standard shape.
@@ -86,3 +87,16 @@
 // ///
 // /// @ingroup input
 // GLFWAPI void glfwDestroyCursor(GLFWcursor* cursor);
+
+test "create" {
+    const allocator = testing.allocator;
+
+    const glfw = @import("main.zig");
+    try glfw.init();
+    defer glfw.terminate();
+
+    const image = try Image.init(allocator, 32, 32, 32 * 32 * 4);
+    defer image.deinit(allocator);
+
+    _ = glfw.Cursor.create(image, 0, 0) catch |err| std.debug.print("failed to create cursor, custom cursors not supported? error={}\n", .{err});
+}