From af2132315d7fc8073e88cbeb50123a7250c0636f Mon Sep 17 00:00:00 2001
From: Oskari Alaranta <oskari.alaranta@bananymous.com>
Date: Mon, 1 Jun 2026 20:40:56 +0300
Subject: [PATCH] Implement WarpPointer

This allows playing games that capture the cursor
---
 xbanan/Base.cpp              | 30 ++++++++++++++++++++++++++++++
 xbanan/Platform.h            |  2 ++
 xbanan/SDL3/sdl3.cpp         | 14 ++++++++++++++
 xbanan/banan-os/banan-os.cpp |  8 ++++++++
 4 files changed, 54 insertions(+)

diff --git a/xbanan/Base.cpp b/xbanan/Base.cpp
index 8b6e7f3..3c84389 100644
--- a/xbanan/Base.cpp
+++ b/xbanan/Base.cpp
@@ -2013,6 +2013,36 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 
 			break;
 		}
+		case X_WarpPointer:
+		{
+			auto request = decode<xWarpPointerReq>(packet).value();
+
+			dprintln("WarpPointer");
+			dprintln("  src_wid: {}", request.srcWid);
+			dprintln("  src_x:   {}", request.srcX);
+			dprintln("  src_y:   {}", request.srcY);
+			dprintln("  src_w:   {}", request.srcWidth);
+			dprintln("  src_h:   {}", request.srcHeight);
+			dprintln("  dst_wid: {}", request.dstWid);
+			dprintln("  dst_x:   {}", request.dstX);
+			dprintln("  dst_y:   {}", request.dstY);
+
+			if (g_platform_ops.warp_pointer == nullptr)
+				break;
+
+			// TODO: source window :)
+
+			if (request.dstWid == None)
+				g_platform_ops.warp_pointer(request.dstX, request.dstY, true);
+			else
+			{
+				(void)TRY_REF(get_window(client_info, request.dstWid, X_WarpPointer));
+				const auto [win_x, win_y] = get_window_position(request.dstWid);
+				g_platform_ops.warp_pointer(win_x + request.dstX, win_y + request.dstY, false);
+			}
+
+			break;
+		}
 		case X_QueryKeymap:
 		{
 			dprintln("QueryKeymap");
diff --git a/xbanan/Platform.h b/xbanan/Platform.h
index b3e1ad2..caca7b9 100644
--- a/xbanan/Platform.h
+++ b/xbanan/Platform.h
@@ -59,6 +59,8 @@ struct PlatformOps
 	void (*request_reposition)(PlatformWindow*, int32_t x, int32_t y);
 	/* Request new fullscreen state, can be async */
 	void (*request_fullscreen)(PlatformWindow*, bool fullscreen);
+	/* Warp pointer */
+	void (*warp_pointer)(int32_t x, int32_t y, bool relative);
 	/* Create a system cursor */
 	BAN::ErrorOr<BAN::UniqPtr<PlatformCursor>> (*create_system_cursor)(SystemCursorType);
 	/* Create cursor from custom bitmap */
diff --git a/xbanan/SDL3/sdl3.cpp b/xbanan/SDL3/sdl3.cpp
index ff2a10c..a55e540 100644
--- a/xbanan/SDL3/sdl3.cpp
+++ b/xbanan/SDL3/sdl3.cpp
@@ -335,6 +335,19 @@ static void sdl3_request_fullscreen(PlatformWindow* window, bool fullscreen)
 	SDL_SetWindowFullscreen(sdl_window.window, fullscreen);
 }
 
+static void sdl3_warp_pointer(int32_t x, int32_t y, bool relative)
+{
+	if (relative)
+	{
+		float cx, cy;
+		SDL_GetGlobalMouseState(&cx, &cy);
+		x += cx;
+		x += cy;
+	}
+
+	SDL_WarpMouseGlobal(x, y);
+}
+
 static BAN::ErrorOr<BAN::UniqPtr<PlatformCursor>> sdl3_create_system_cursor(SystemCursorType type)
 {
 	static constexpr SDL_SystemCursor cursor_type_map[] {
@@ -414,6 +427,7 @@ PlatformOps g_platform_ops = {
 	.request_resize       = sdl3_request_resize,
 	.request_reposition   = sdl3_request_reposition,
 	.request_fullscreen   = sdl3_request_fullscreen,
+	.warp_pointer         = sdl3_warp_pointer,
 	.create_system_cursor = sdl3_create_system_cursor,
 	.create_bitmap_cursor = sdl3_create_bitmap_cursor,
 	.set_cursor           = sdl3_set_cursor,
diff --git a/xbanan/banan-os/banan-os.cpp b/xbanan/banan-os/banan-os.cpp
index 042974e..99d24db 100644
--- a/xbanan/banan-os/banan-os.cpp
+++ b/xbanan/banan-os/banan-os.cpp
@@ -147,6 +147,13 @@ static void bananos_request_fullscreen(PlatformWindow* window, bool fullscreen)
 	banan_window.window->set_fullscreen(fullscreen);
 }
 
+static void bananos_warp_pointer(int32_t x, int32_t y, bool relative)
+{
+	(void)x;
+	(void)y;
+	(void)relative;
+}
+
 static BAN::ErrorOr<BAN::UniqPtr<PlatformCursor>> bananos_create_system_cursor(SystemCursorType type)
 {
 	(void)type;
@@ -190,6 +197,7 @@ PlatformOps g_platform_ops = {
 	.request_resize       = bananos_request_resize,
 	.request_reposition   = bananos_request_reposition,
 	.request_fullscreen   = bananos_request_fullscreen,
+	.warp_pointer         = bananos_warp_pointer,
 	.create_system_cursor = bananos_create_system_cursor,
 	.create_bitmap_cursor = bananos_create_bitmap_cursor,
 	.set_cursor           = bananos_set_cursor,