From c581764e236ab115d50f7a362c1b9abb02962a24 Mon Sep 17 00:00:00 2001
From: Jeffrey Pfau <jeffrey@endrift.com>
Date: Sat, 6 Feb 2016 19:29:27 -0800
Subject: [PATCH] GB Video: Fix strange window y behavior when paritally
 disabled

---
 src/gb/renderers/software.c | 9 ++++++---
 src/gb/renderers/software.h | 1 +
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/gb/renderers/software.c b/src/gb/renderers/software.c
index 0f565a8a6..0edb0742d 100644
--- a/src/gb/renderers/software.c
+++ b/src/gb/renderers/software.c
@@ -63,6 +63,7 @@ static void GBVideoSoftwareRendererReset(struct GBVideoRenderer* renderer) {
 	softwareRenderer->scy = 0;
 	softwareRenderer->scx = 0;
 	softwareRenderer->wy = 0;
+	softwareRenderer->currentWy = 0;
 	softwareRenderer->wx = 0;
 }
 
@@ -120,13 +121,14 @@ static void GBVideoSoftwareRendererDrawDot(struct GBVideoRenderer* renderer, int
 	if (GBRegisterLCDCIsBgEnable(softwareRenderer->lcdc)) {
 		GBVideoSoftwareRendererDrawBackground(softwareRenderer, maps, x, y, softwareRenderer->scx, softwareRenderer->scy);
 
-		if (GBRegisterLCDCIsWindow(softwareRenderer->lcdc) && softwareRenderer->wy <= y) {
+		if (GBRegisterLCDCIsWindow(softwareRenderer->lcdc) && softwareRenderer->wy <= y && x >= softwareRenderer->wx - 7) {
 			maps = &softwareRenderer->d.vram[GB_BASE_MAP];
 			if (GBRegisterLCDCIsWindowTileMap(softwareRenderer->lcdc)) {
 				maps += GB_SIZE_MAP;
 			}
-			if (x >= softwareRenderer->wx - 7) {
-				GBVideoSoftwareRendererDrawBackground(softwareRenderer, maps, x, y, 7 - softwareRenderer->wx, -softwareRenderer->wy);
+			GBVideoSoftwareRendererDrawBackground(softwareRenderer, maps, x, y, 7 - softwareRenderer->wx, (softwareRenderer->currentWy - y) - softwareRenderer->wy);
+			if (x == 159) { // TODO: Find a better way to do this
+				++softwareRenderer->currentWy;
 			}
 		}
 	} else {
@@ -151,6 +153,7 @@ static void GBVideoSoftwareRendererFinishFrame(struct GBVideoRenderer* renderer)
 		mappedMemoryFree(softwareRenderer->temporaryBuffer, GB_VIDEO_HORIZONTAL_PIXELS * GB_VIDEO_VERTICAL_PIXELS * 4);
 		softwareRenderer->temporaryBuffer = 0;
 	}
+	softwareRenderer->currentWy = 0;
 }
 
 static void GBVideoSoftwareRendererDrawBackground(struct GBVideoSoftwareRenderer* renderer, uint8_t* maps, int x, int y, int sx, int sy) {
diff --git a/src/gb/renderers/software.h b/src/gb/renderers/software.h
index 6ee910ead..a40741a86 100644
--- a/src/gb/renderers/software.h
+++ b/src/gb/renderers/software.h
@@ -27,6 +27,7 @@ struct GBVideoSoftwareRenderer {
 	uint8_t scx;
 	uint8_t wy;
 	uint8_t wx;
+	uint8_t currentWy;
 
 	GBRegisterLCDC lcdc;
 };