initial support for RG351M controller input

src/main.zig

@@ -127,6 +127,36 @@ pub fn main() !void {
     }
     defer seizer.backend.glfw.c.glfwTerminate();
 
+    // update joystick to gamepad mappings
+    update_gamepad_mappings_file: {
+        const sdl_controller_config_filepath = std.process.getEnvVarOwned(gpa.allocator(), "SDL_GAMECONTROLLERCONFIG_FILE") catch break :update_gamepad_mappings_file;
+        defer gpa.allocator().free(sdl_controller_config_filepath);
+
+        const controller_config_data = std.fs.cwd().readFileAllocOptions(
+            gpa.allocator(),
+            sdl_controller_config_filepath,
+            512 * 1024 * 1024,
+            null,
+            @alignOf(u8),
+            0,
+        ) catch break :update_gamepad_mappings_file;
+        defer gpa.allocator().free(controller_config_data);
+
+        if (seizer.backend.glfw.c.glfwUpdateGamepadMappings(controller_config_data) == 0) {
+            std.log.warn("Failed to update gamepad mappings from file", .{});
+        }
+    }
+    update_gamepad_mappings: {
+        const sdl_controller_config = std.process.getEnvVarOwned(gpa.allocator(), "SDL_GAMECONTROLLERCONFIG") catch break :update_gamepad_mappings;
+        defer gpa.allocator().free(sdl_controller_config);
+
+        const sdl_controller_configz = gpa.allocator().dupeZ(u8, sdl_controller_config) catch break :update_gamepad_mappings;
+
+        if (seizer.backend.glfw.c.glfwUpdateGamepadMappings(sdl_controller_configz) == 0) {
+            std.log.warn("Failed to update gamepad mappings from environment variable", .{});
+        }
+    }
+
     seizer.backend.glfw.c.glfwWindowHint(seizer.backend.glfw.c.GLFW_OPENGL_DEBUG_CONTEXT, seizer.backend.glfw.c.GLFW_TRUE);
     seizer.backend.glfw.c.glfwWindowHint(seizer.backend.glfw.c.GLFW_CLIENT_API, seizer.backend.glfw.c.GLFW_OPENGL_ES_API);
     seizer.backend.glfw.c.glfwWindowHint(seizer.backend.glfw.c.GLFW_CONTEXT_VERSION_MAJOR, 3);
@@ -184,6 +214,12 @@ pub fn main() !void {
     // TODO: Restore hovered_action when undoing
     var hovered_action: ?Action = null;
 
+    if (seizer.backend.glfw.c.glfwJoystickIsGamepad(seizer.backend.glfw.c.GLFW_JOYSTICK_1) != 0) {
+        std.log.info("detected gamepad = \"{?s}\" {?s}", .{ seizer.backend.glfw.c.glfwGetGamepadName(seizer.backend.glfw.c.GLFW_JOYSTICK_1), seizer.backend.glfw.c.glfwGetJoystickGUID(seizer.backend.glfw.c.GLFW_JOYSTICK_1) });
+    } else if (seizer.backend.glfw.c.glfwJoystickPresent(seizer.backend.glfw.c.GLFW_JOYSTICK_1) != 0) {
+        std.log.info("detected joystick = \"{?s}\" {?s}", .{ seizer.backend.glfw.c.glfwGetJoystickName(seizer.backend.glfw.c.GLFW_JOYSTICK_1), seizer.backend.glfw.c.glfwGetJoystickGUID(seizer.backend.glfw.c.GLFW_JOYSTICK_1) });
+    }
+
     while (seizer.backend.glfw.c.glfwWindowShouldClose(window) != seizer.backend.glfw.c.GLFW_TRUE) {
         input_state = .{
             .left = false,
@@ -195,6 +231,36 @@ pub fn main() !void {
         };
         seizer.backend.glfw.c.glfwPollEvents();
 
+        if (seizer.backend.glfw.c.glfwJoystickIsGamepad(seizer.backend.glfw.c.GLFW_JOYSTICK_1) != 0) {
+            var gamepad_state: seizer.backend.glfw.c.GLFWgamepadstate = undefined;
+            if (seizer.backend.glfw.c.glfwGetGamepadState(seizer.backend.glfw.c.GLFW_JOYSTICK_1, &gamepad_state) != 0) {
+                input_state.left = input_state.left or gamepad_state.buttons[seizer.backend.glfw.c.GLFW_GAMEPAD_BUTTON_DPAD_LEFT] != 0;
+                input_state.right = input_state.right or gamepad_state.buttons[seizer.backend.glfw.c.GLFW_GAMEPAD_BUTTON_DPAD_RIGHT] != 0;
+                input_state.up = input_state.up or gamepad_state.buttons[seizer.backend.glfw.c.GLFW_GAMEPAD_BUTTON_DPAD_UP] != 0;
+                input_state.down = input_state.down or gamepad_state.buttons[seizer.backend.glfw.c.GLFW_GAMEPAD_BUTTON_DPAD_DOWN] != 0;
+            }
+        } else if (seizer.backend.glfw.c.glfwJoystickPresent(seizer.backend.glfw.c.GLFW_JOYSTICK_1) != 0) {
+            var hats_count: c_int = undefined;
+            const hats_ptr = seizer.backend.glfw.c.glfwGetJoystickHats(seizer.backend.glfw.c.GLFW_JOYSTICK_1, &hats_count);
+            const hats = hats_ptr[0..@intCast(hats_count)];
+
+            const HAT_UP = seizer.backend.glfw.c.GLFW_HAT_UP;
+            const HAT_RIGHT = seizer.backend.glfw.c.GLFW_HAT_RIGHT;
+            const HAT_DOWN = seizer.backend.glfw.c.GLFW_HAT_DOWN;
+            const HAT_LEFT = seizer.backend.glfw.c.GLFW_HAT_LEFT;
+
+            input_state.left = input_state.left or hats[0] & HAT_LEFT != 0;
+            input_state.right = input_state.right or hats[0] & HAT_RIGHT != 0;
+            input_state.up = input_state.up or hats[0] & HAT_UP != 0;
+            input_state.down = input_state.down or hats[0] & HAT_DOWN != 0;
+
+            var buttons_count: c_int = undefined;
+            const buttons_ptr = seizer.backend.glfw.c.glfwGetJoystickButtons(seizer.backend.glfw.c.GLFW_JOYSTICK_1, &buttons_count);
+            const buttons = buttons_ptr[0..@intCast(buttons_count)];
+            input_state.action = input_state.action or buttons[0] != 0;
+            input_state.undo = input_state.undo or buttons[1] != 0;
+        }
+
         var request_command: ?[]const u8 = null;
         defer if (request_command) |command| gpa.allocator().free(command);