From 1c0d66aef72c22aaa2001ad4470e755b411c6c15 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Henrik=20Rydg=C3=A5rd?= <hrydgard@gmail.com>
Date: Mon, 26 Sep 2022 20:47:55 +0200
Subject: [PATCH] Add compatibility flag for loading pixels on framebuffer
 create using nearest filtering

Solves the last problem with the speedometers - so we can finally say: Fixes #8509

Render-to-CLUT for speedometers renders on top of an image that just comes from the
underlying memory, so it's been drawn to the framebuffer with DrawPixels. That adds
filtering so at higher resolutions, there's some blurring of the CLUT, causing
artifacts.  We can solve this two ways: either we force on lower-resolution-for-effects
for Ridge Racer games, or we use nearest filtering when doing DrawPixels of the
memory under a framebuffer. For best result, we do the latter.

(The speedometers look even better with nearest filtering, but that's a more
general issue of UI looking better that way).
---
 Core/Compatibility.cpp                  |  1 +
 Core/Compatibility.h                    |  1 +
 GPU/Common/FramebufferManagerCommon.cpp |  6 +++++-
 assets/compat.ini                       | 21 +++++++++++++++++++++
 4 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/Core/Compatibility.cpp b/Core/Compatibility.cpp
index f86ebbbcea6f..94b4279a39ac 100644
--- a/Core/Compatibility.cpp
+++ b/Core/Compatibility.cpp
@@ -109,6 +109,7 @@ void Compatibility::CheckSettings(IniFile &iniFile, const std::string &gameID) {
 	CheckSetting(iniFile, gameID, "SplitFramebufferMargin", &flags_.SplitFramebufferMargin);
 	CheckSetting(iniFile, gameID, "ForceLowerResolutionForEffectsOn", &flags_.ForceLowerResolutionForEffectsOn);
 	CheckSetting(iniFile, gameID, "AllowDownloadCLUT", &flags_.AllowDownloadCLUT);
+	CheckSetting(iniFile, gameID, "NearestFilteringOnFramebufferCreate", &flags_.NearestFilteringOnFramebufferCreate);
 }
 
 void Compatibility::CheckSetting(IniFile &iniFile, const std::string &gameID, const char *option, bool *flag) {
diff --git a/Core/Compatibility.h b/Core/Compatibility.h
index 0fee77b805f1..bd824b916d10 100644
--- a/Core/Compatibility.h
+++ b/Core/Compatibility.h
@@ -89,6 +89,7 @@ struct CompatFlags {
 	bool SplitFramebufferMargin;
 	bool ForceLowerResolutionForEffectsOn;
 	bool AllowDownloadCLUT;
+	bool NearestFilteringOnFramebufferCreate;
 };
 
 struct VRCompat {
diff --git a/GPU/Common/FramebufferManagerCommon.cpp b/GPU/Common/FramebufferManagerCommon.cpp
index 330eda479682..9a666f83f8a8 100644
--- a/GPU/Common/FramebufferManagerCommon.cpp
+++ b/GPU/Common/FramebufferManagerCommon.cpp
@@ -1061,7 +1061,11 @@ void FramebufferManagerCommon::DrawPixels(VirtualFramebuffer *vfb, int dstX, int
 
 	DrawTextureFlags flags;
 	if (useBufferedRendering_ && vfb && vfb->fbo) {
-		flags = channel == RASTER_COLOR ? DRAWTEX_LINEAR : DRAWTEX_NEAREST;
+		if (channel == RASTER_DEPTH || PSP_CoreParameter().compat.flags().NearestFilteringOnFramebufferCreate) {
+			flags = DRAWTEX_NEAREST;
+		} else {
+			flags = DRAWTEX_LINEAR;
+		}
 		draw_->BindFramebufferAsRenderTarget(vfb->fbo, { Draw::RPAction::KEEP, Draw::RPAction::KEEP, Draw::RPAction::KEEP }, tag);
 		SetViewport2D(0, 0, vfb->renderWidth, vfb->renderHeight);
 		draw_->SetScissorRect(0, 0, vfb->renderWidth, vfb->renderHeight);
diff --git a/assets/compat.ini b/assets/compat.ini
index 8457a6a36f87..a86f7562b3d1 100644
--- a/assets/compat.ini
+++ b/assets/compat.ini
@@ -1283,6 +1283,27 @@ ULJM05494 = true
 NPJH50143 = true
 ULJM05738 = true
 
+[NearestFilteringOnFramebufferCreate]
+# Ridge Racer speedometer dynamic CLUT problem - they rely on some palette entries
+# from memory, and render to the rest of the palette. The palette entries loaded from memory
+# must not be blurred by filtering, so nearest it is. See issue #8509
+
+# Ridge Racer
+ULJS00001 = true
+ULUS10001 = true
+UCKS45002 = true
+UCES00002 = true
+ULJS19002 = true
+UCKS45053 = true
+NPJH50140 = true
+
+# Ridge Racer 2
+ULJS00080 = true
+UCKS45032 = true
+UCES00422 = true
+UCAS40273 = true
+NPJH50366 = true
+
 [AllowDownloadCLUT]
 # Temporary compatibility option, while working on the GPU CLUT-from-framebuffer path.
 # Not required for any games now that it works, but might be useful for development.