From 8a0f287d8c67c9bd74f2479aabe15b6418ba782a Mon Sep 17 00:00:00 2001
From: Oskari Alaranta <oskari.alaranta@bananymous.com>
Date: Sat, 21 Feb 2026 04:32:48 +0200
Subject: [PATCH] Send NoExposure in CopyArea

Im not sure if/when i should be sending GraphicsExposure but this fixes
xterm hanging when scrolling
---
 xbanan/Base.cpp      | 36 ++++++++++++++++++++++++++++++++++--
 xbanan/Definitions.h |  2 ++
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/xbanan/Base.cpp b/xbanan/Base.cpp
index 6762caa..7c277a4 100644
--- a/xbanan/Base.cpp
+++ b/xbanan/Base.cpp
@@ -2466,6 +2466,7 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 			uint32_t foreground = 0x000000;
 			uint32_t background = 0x000000;
 			uint32_t font = None;
+			bool graphics_exposures = true;
 			uint32_t clip_mask = 0;
 			int32_t clip_origin_x = 0;
 			int32_t clip_origin_y = 0;
@@ -2489,6 +2490,10 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 						dprintln("    font: {}", value);
 						font = value;
 						break;
+					case 16:
+						dprintln("    graphics-exposures: {}", value);
+						graphics_exposures = value;
+						break;
 					case 17:
 						dprintln("    clip-origin-x: {}", value);
 						clip_origin_x = value;
@@ -2514,6 +2519,7 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 					.foreground = foreground,
 					.background = background,
 					.font = font,
+					.graphics_exposures = graphics_exposures,
 					.clip_mask = clip_mask,
 					.clip_origin_x = clip_origin_x,
 					.clip_origin_y = clip_origin_y,
@@ -2557,6 +2563,10 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 						dprintln("    font: {}", value);
 						gc.font = value;
 						break;
+					case 16:
+						dprintln("    graphics-exposures: {}", value);
+						gc.graphics_exposures = value;
+						break;
 					case 17:
 						dprintln("    clip-origin-x: {}", value);
 						gc.clip_origin_x = value;
@@ -2727,7 +2737,15 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 					}	
 				};
 
-			for (int32_t yoff = 0; yoff < request.height; yoff++)
+			const int32_t start_x = request.srcX < request.dstX ? request.width - 1 : 0;
+			const int32_t stop_x  = request.srcX < request.dstX ? -1 : request.width;
+			const int32_t step_x  = request.srcX < request.dstX ? -1 : 1;
+
+			const int32_t start_y = request.srcY < request.dstY ? request.height - 1 : 0;
+			const int32_t stop_y  = request.srcY < request.dstY ? -1 : request.height;
+			const int32_t step_y  = request.srcY < request.dstY ? -1 : 1;
+
+			for (int32_t yoff = start_y; yoff != stop_y; yoff += step_y)
 			{
 				const int32_t src_y = request.srcY + yoff;
 				const int32_t dst_y = request.dstY + yoff;
@@ -2735,7 +2753,7 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 					continue;
 				if (dst_y < 0 || dst_y >= dst_h)
 					continue;
-				for (int32_t xoff = 0; xoff < request.width; xoff++)
+				for (int32_t xoff = start_x; xoff != stop_x; xoff += step_x)
 				{
 					const int32_t src_x = request.srcX + xoff;
 					const int32_t dst_x = request.dstX + xoff;
@@ -2748,6 +2766,20 @@ BAN::ErrorOr<void> handle_packet(Client& client_info, BAN::ConstByteSpan packet)
 				}
 			}
 
+			if (gc.graphics_exposures)
+			{
+				xEvent event = { .u = {
+					.noExposure = {
+						.drawable = request.dstDrawable,
+						.minorEvent = 0,
+						.majorEvent = X_CopyArea,
+					}
+				}};
+				event.u.u.type = NoExpose;
+				event.u.u.sequenceNumber = client_info.sequence;
+				TRY(encode(client_info.output_buffer, event));
+			}
+
 			if (dst_drawable.type == Object::Type::Window)
 				invalidate_window(request.dstDrawable, request.dstX, request.dstY, request.width, request.height);
 
diff --git a/xbanan/Definitions.h b/xbanan/Definitions.h
index 2dc7774..dd4e6e7 100644
--- a/xbanan/Definitions.h
+++ b/xbanan/Definitions.h
@@ -114,6 +114,8 @@ struct Object
 
 		uint32_t font;
 
+		bool graphics_exposures;
+
 		uint32_t clip_mask;
 		int32_t clip_origin_x;
 		int32_t clip_origin_y;