From: Toni Wilen <twilen@winuae.net>
Date: Wed, 27 Mar 2024 18:13:44 +0000 (+0200)
Subject: Fix vblank start/end position in programmed modes and fix also ECS Denise special... 
X-Git-Tag: 5300~67
X-Git-Url: https://git.unchartedbackwaters.co.uk/w/?a=commitdiff_plain;h=f77a0750bb3f13a2831a04f3b6a33b3715b5e63a;p=francis%2Fwinuae.git

Fix vblank start/end position in programmed modes and fix also ECS Denise special case.
---

diff --git a/custom.cpp b/custom.cpp
index 4d0e8536..f023e6ed 100644
--- a/custom.cpp
+++ b/custom.cpp
@@ -6279,15 +6279,17 @@ static void reset_decisions_hsync_start(void)
 	thisline_decision.fmode = fmode;
 
 	if (!aga_mode && ecs_denise && exthblank) {
-		// ECS Denise + EXTBLANK: VBLANK blanking is different
-		thisline_decision.vb = VB_NOVB;
+		// ECS Denise + EXTBLANK: VBLANK blanking is different.
 		if (new_beamcon0 & BEAMCON0_BLANKEN) {
-			// blanking working same as AGA
-			thisline_decision.vb = vb_start_line >= 1 + vblank_extraline || vb_end_next_line ? 0 : VB_NOVB;
+			// Follow Agnus VBLANK state directly via CSYNC connection. Ignore strobe vblank state.
+			thisline_decision.vb = vb_state || vb_end_line ? VB_PRGVB : VB_NOVB;
+		} else {
+			// CSYNC: follow CSYNC state
+			thisline_decision.vb = vs_state_on ? VB_PRGVB : VB_NOVB;
 		}
 	} else if (ecs_agnus) {
 		// Visible vblank end is delayed by 1 line
-		thisline_decision.vb = vb_start_line >= 1 + vblank_extraline || vb_end_next_line ? 0 : VB_NOVB;
+		thisline_decision.vb = vb_start_line >= 2 + vblank_extraline || vb_end_next_line ? 0 : VB_NOVB;
 	} else {
 		thisline_decision.vb = vb_start_line >= 2 + vblank_extraline || vb_end_next_line ? 0 : VB_NOVB;
 	}