From 4f206d2773a09942669b2263032deba6657dc69a Mon Sep 17 00:00:00 2001
From: Flyinghead <raphael.jean@gmail.com>
Date: Tue, 12 Jul 2022 15:55:49 +0200
Subject: [PATCH] pvr: set correct framebuffer size in 240p/pixel_double

Some games use 240p and pixel_double resulting in a 320x240 framebuffer.
Renderer should be resized accordingly.
Fixes linear filtering artifact in KoF dream match 1999 (Issue #690)
---
 core/emulator.cpp           |  1 +
 core/hw/pvr/Renderer_if.cpp | 31 ++++++++++++++++++++++---------
 core/hw/pvr/Renderer_if.h   |  1 +
 core/hw/pvr/pvr_regs.cpp    | 11 +++++++++++
 4 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/core/emulator.cpp b/core/emulator.cpp
index 22ddf1b9f..0841862eb 100644
--- a/core/emulator.cpp
+++ b/core/emulator.cpp
@@ -811,6 +811,7 @@ bool Emulator::checkStatus()
 
 bool Emulator::render()
 {
+	rend_resize_renderer_if_needed();
 	if (!config::ThreadedRendering)
 	{
 		if (state != Running)
diff --git a/core/hw/pvr/Renderer_if.cpp b/core/hw/pvr/Renderer_if.cpp
index 2445cf983..6bf4f410d 100644
--- a/core/hw/pvr/Renderer_if.cpp
+++ b/core/hw/pvr/Renderer_if.cpp
@@ -38,6 +38,7 @@ bool fb_dirty;
 static bool pend_rend;
 
 TA_context* _pvrrc;
+extern bool rend_needs_resize;
 
 static bool rend_frame(TA_context* ctx)
 {
@@ -363,32 +364,44 @@ void rend_deserialize(Deserializer& deser)
 		deser >> fb_watch_addr_end;
 	}
 	pend_rend = false;
+	rend_needs_resize = true;
 }
 
 void rend_resize_renderer()
 {
 	if (renderer == nullptr)
 		return;
-	float hres;
-	int vres = config::RenderResolution;
+	int fbwidth = VO_CONTROL.pixel_double ? 320 : 640;
+	int fbheight = (SPG_CONTROL.PAL == SPG_CONTROL.NTSC) || SPG_CONTROL.interlace == 1 ? 480 : 240;
+
+	float upscaling = config::RenderResolution / 480.f;
+	float hres = fbwidth * upscaling;
+	float vres = fbheight * upscaling;
 	if (config::Widescreen && !config::Rotate90)
 	{
 		if (config::SuperWidescreen)
-			hres = (float)config::RenderResolution * settings.display.width / settings.display.height;
+			hres = vres * settings.display.width / settings.display.height;
 		else
-			hres = config::RenderResolution * 16.f / 9.f;
+			hres *= 4.f / 3.f;
 	}
 	else if (config::Rotate90)
 	{
-		vres = vres * config::ScreenStretching / 100;
-		hres = config::RenderResolution * 4.f / 3.f;
+		vres *= config::ScreenStretching / 100.f;
 	}
 	else
 	{
-		hres = config::RenderResolution * 4.f * config::ScreenStretching / 3.f / 100.f;
+		hres *= config::ScreenStretching / 100.f;
 	}
 	if (!config::Rotate90)
 		hres = std::roundf(hres / 2.f) * 2.f;
-	DEBUG_LOG(RENDERER, "rend_resize_renderer: %d x %d", (int)hres, vres);
-	renderer->Resize((int)hres, vres);
+	DEBUG_LOG(RENDERER, "rend_resize_renderer: %d x %d", (int)hres, (int)vres);
+	renderer->Resize((int)hres, (int)vres);
+	rend_needs_resize = false;
+}
+
+void rend_resize_renderer_if_needed()
+{
+	if (!rend_needs_resize)
+		return;
+	rend_resize_renderer();
 }
diff --git a/core/hw/pvr/Renderer_if.h b/core/hw/pvr/Renderer_if.h
index e5ac5f50b..5e8b80e51 100644
--- a/core/hw/pvr/Renderer_if.h
+++ b/core/hw/pvr/Renderer_if.h
@@ -21,6 +21,7 @@ void rend_allow_rollback();
 void rend_serialize(Serializer& ser);
 void rend_deserialize(Deserializer& deser);
 void rend_resize_renderer();
+void rend_resize_renderer_if_needed();
 
 ///////
 extern TA_context* _pvrrc;
diff --git a/core/hw/pvr/pvr_regs.cpp b/core/hw/pvr/pvr_regs.cpp
index 261b5babd..bedd415eb 100644
--- a/core/hw/pvr/pvr_regs.cpp
+++ b/core/hw/pvr/pvr_regs.cpp
@@ -7,6 +7,7 @@
 
 bool pal_needs_update=true;
 bool fog_needs_update=true;
+bool rend_needs_resize = true;
 
 u8 pvr_regs[pvr_RegSize];
 
@@ -159,6 +160,16 @@ void pvr_WriteReg(u32 paddr,u32 data)
 		{
 			PvrReg(addr, u32) = data;
 			CalculateSync();
+			if (addr == SPG_CONTROL_addr)
+				rend_needs_resize = true;
+		}
+		return;
+
+	case VO_CONTROL_addr:
+		if (PvrReg(addr, u32) != data)
+		{
+			PvrReg(addr, u32) = data;
+			rend_needs_resize = true;
 		}
 		return;