GS/HW: Rewrite vertices if large ST.

Adds vertex rewriting functionality to both HW/SW. Aggressive version is user hack. Adds a GameDB hack for Ridge Racer V and Destruction Derby Arena. For SW, a less aggressive version is used if the hack is not enabled.

bin/resources/GameIndex.yaml

@@ -4706,6 +4706,7 @@ SCES-50000:
     gpuPaletteConversion: 2 # Lots of CLUTs in large textures.
     cpuSpriteRenderBW: 1 # Fixes car textures.
     cpuSpriteRenderLevel: 1 # Needed for above.
+    rewriteLargeST: 1 # Fix reflections on cars.
 SCES-50001:
   name: "Tekken Tag Tournament"
   region: "PAL-M5"
@@ -35387,6 +35388,7 @@ SLPM-60109:
     gpuPaletteConversion: 2 # Lots of CLUTs in large textures.
     cpuSpriteRenderBW: 1 # Fixes car textures.
     cpuSpriteRenderLevel: 1 # Needed for above.
+    rewriteLargeST: 1 # Fix reflections on cars.
 SLPM-60112:
   name: "フレースヴェルグ [体験版]"
   name-sort: "ふれーすヴぇるぐ [たいけんばん]"
@@ -54809,6 +54811,7 @@ SLPS-20001:
     gpuPaletteConversion: 2 # Lots of CLUTs in large textures.
     cpuSpriteRenderBW: 1 # Fixes car textures.
     cpuSpriteRenderLevel: 1 # Needed for above.
+    rewriteLargeST: 1 # Fix reflections on cars.
 SLPS-20002:
   name: "撞球 ビリヤードマスター2"
   name-sort: "どうきゅう びりやーどますたー2"
@@ -63501,6 +63504,7 @@ SLPS-71502:
     gpuPaletteConversion: 2 # Lots of CLUTs in large textures.
     cpuSpriteRenderBW: 1 # Fixes car textures.
     cpuSpriteRenderLevel: 1 # Needed for above.
+    rewriteLargeST: 1 # Fix reflections on cars.
 SLPS-72501:
   name: "ファイナルファンタジーⅩ [MEGA HITS!]"
   name-sort: "ふぁいなるふぁんたじー10 [MEGA HITS!]"
@@ -64503,6 +64507,7 @@ SLUS-20002:
     gpuPaletteConversion: 2 # Lots of CLUTs in large textures.
     cpuSpriteRenderBW: 1 # Fixes car textures.
     cpuSpriteRenderLevel: 1 # Needed for above.
+    rewriteLargeST: 1 # Fix reflections on cars.
 SLUS-20003:
   name: "Portal Runner"
   region: "NTSC-U"

pcsx2-qt/Settings/GraphicsHardwareFixesSettingsTab.ui

@@ -271,6 +271,13 @@
    </item>
    <item row="7" column="0" colspan="2">
    <layout class="QGridLayout" name="hwFixesLayout">
+     <item row="5" column="0">
+      <widget class="QCheckBox" name="rewriteLargeST">
+       <property name="text">
+        <string>Rewrite Large ST</string>
+       </property>
+      </widget>
+     </item>
      <item row="4" column="1">
       <widget class="QCheckBox" name="drawBuffering">
        <property name="text">
@@ -389,6 +396,7 @@
   <tabstop>disableRenderFixes</tabstop>
   <tabstop>readTCOnClose</tabstop>
   <tabstop>estimateTextureRegion</tabstop>
+  <tabstop>rewriteLargeST</tabstop>
  </tabstops>
  <resources/>
  <connections/>

pcsx2-qt/Settings/GraphicsSettingsWidget.cpp

@@ -155,6 +155,7 @@ GraphicsSettingsWidget::GraphicsSettingsWidget(SettingsWindow* settings_dialog,
 	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_fixes.readTCOnClose, "EmuCore/GS", "UserHacks_ReadTCOnClose", false);
 	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_fixes.estimateTextureRegion, "EmuCore/GS", "UserHacks_EstimateTextureRegion", false);
 	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_fixes.drawBuffering, "EmuCore/GS", "UserHacks_DrawBuffering", false);
+	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_fixes.rewriteLargeST, "EmuCore/GS", "UserHacks_RewriteLargeST", false);
 	SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_fixes.gpuPaletteConversion, "EmuCore/GS", "paltex", false);
 	connect(m_fixes.cpuSpriteRenderBW, &QComboBox::currentIndexChanged, this,
 		&GraphicsSettingsWidget::onCPUSpriteRenderBWChanged);
@@ -636,6 +637,9 @@ GraphicsSettingsWidget::GraphicsSettingsWidget(SettingsWindow* settings_dialog,
 
 		dialog()->registerWidgetHelp(m_fixes.drawBuffering, tr("Draw Buffering"), tr("Unchecked"),
 			tr("Attempts to reduce draw calls in games which do heavy context switching for blending purposes."));
+		
+		dialog()->registerWidgetHelp(m_fixes.rewriteLargeST, tr("Rewrite Large ST"), tr("Unchecked"),
+			tr("Rewrite large ST coordinates and clamp the values (mainly for Ridge Racer V)."));
 	}
 
 	// Upscaling Fixes tab

pcsx2/Config.h

@@ -811,6 +811,7 @@ struct Pcsx2Config
 					UserHacks_NativePaletteDraw : 1,
 					UserHacks_EstimateTextureRegion : 1,
 					UserHacks_DrawBuffering : 1,
+					UserHacks_RewriteLargeST : 1,
 					FXAA : 1,
 					ShadeBoost : 1,
 					DumpGSData : 1,

pcsx2/Docs/GameIndex.md

@@ -174,7 +174,8 @@ The clamp modes are also numerically based.
 * cpuSpriteRenderBW           [Value between `0` to `10`]   {Disabled, 1 (64), 2 (128), 3 (192), 4 (256), 5 (320), 6 (384), 7 (448), 8 (512), 9 (576), 10 (640)} Default: Off (`0`)
 * cpuSpriteRenderLevel        [`0` or `1` or `2`]    {Sprites only, Sprites/Triangles, Blended Sprites/Triangles}  Default: Off unless cpuSpriteRenderBW has value other than Off then it is 'Sprites only' (`0`)
 * estimateTextureRegion       [`0` or `1`]          {Off, On}                               Default: Off (`0`)
-* drawBuffering			      [`0` or `1`]          {Off, On}                               Default: Off (`0`)
+* drawBuffering               [`0` or `1`]          {Off, On}                               Default: Off (`0`)
+* rewriteLargeST              [`0` or `1`]          {Off, On} Default: Off (`0`)
 * getSkipCount                {`GSC` with suffix }  {None unless specific game GSC}         Default: Disabled (`0`) unless valid variable name (ex. GSC_PolyphonyDigitalGames, GSC_UrbanReign, ...)
 * gpuPaletteConversion        [`0` or `1`]          {Off, On}                               Default: Off (`0`)
 * gpuTargetCLUT               [`0` or `1` or `2`]   {Disabled, Enabled (Exact Match), Enabled (Check Inside Target)}                     Default: Disabled (`0`)

pcsx2/Docs/gamedb-schema.json

@@ -204,7 +204,12 @@
               "minimum": 0,
               "maximum": 1
             },
-			"drawBuffering": {
+            "drawBuffering": {
+              "type": "integer",
+              "minimum": 0,
+              "maximum": 1
+            },
+            "rewriteLargeST": {
               "type": "integer",
               "minimum": 0,
               "maximum": 1

pcsx2/GS/GSState.cpp

@@ -6838,6 +6838,159 @@ GIFRegTEX0 GSState::GetTex0Layer(u32 lod)
 	return TEX0;
 }
 
+// Fix large ST coorindates that may cause graphical glitches.
+template <u32 primclass>
+void GSState::RewriteVerticesIfLargeSTImpl(const GSVector4& large_val, bool check_clamp_mode)
+{
+	// Need to be texture mapping with ST and not have so many vertices that rewritten indices will overflow.
+	if (PRIM->TME && PRIM->FST == 0)
+	{
+		const float tw = static_cast<float>(1 << m_context->TEX0.TW);
+		const float th = static_cast<float>(1 << m_context->TEX0.TH);
+		const GSVector4 tsize = GSVector4(tw, th, 1.0f, 1.0f);
+
+		// Only rewrite big/small S or T when the clamping mode is CLAMP or REGION_CLAMP (if requested).
+		const GIFRegCLAMP& clamp = m_context->CLAMP;
+		const GSVector4 clamp_mask =
+			check_clamp_mode ?
+				GSVector4::cast(GSVector4i(
+					(clamp.WMS == CLAMP_CLAMP || clamp.WMS == CLAMP_REGION_CLAMP) ? 0xFFFFFFFF : 0,
+					(clamp.WMT == CLAMP_CLAMP || clamp.WMT == CLAMP_REGION_CLAMP) ? 0xFFFFFFFF : 0,
+					0,
+					0)) :
+				GSVector4::cast(GSVector4i::cxpr(0xFFFFFFFF));
+
+		const GSVector4 tex_bbox = m_vt.m_min.t.xyxy(m_vt.m_max.t) / tsize.xyxy();
+		const bool large_st = ((tex_bbox.abs() >= large_val) & clamp_mask).mask() || m_vt.nan.value;
+
+		if (large_st)
+		{
+			GL_PUSH("Large ST detected, rewriting vertices.");
+			if (m_index->tail > UINT16_MAX)
+			{
+				GL_INS("Too many vertices to rewrite safely, exiting.");
+				DevCon.Warning("Large ST detected but too many vertices to rewrite safely.");
+				return;
+			}
+
+			constexpr int n = GSUtil::GetClassVertexCount(primclass);
+
+			// Make sure the copy buffer is large enough.
+			while (m_max_vertex_count < m_index->tail)
+				GrowVertexBuffer();
+
+			GSVertex* RESTRICT vertex = m_vertex->buff;
+			GSVertex* RESTRICT vertex_copy = m_vertex->buff_copy;
+			u16* RESTRICT index = m_index->buff;
+			const int count = static_cast<int>(m_index->tail);
+
+			for (int i = 0; i < count; i += n)
+			{
+				GSVector4 stcq[n];
+
+				// Load STQ for this primitive.
+				for (int j = 0; j < n; j++)
+					stcq[j] = GSVector4::cast(GSVector4i(vertex[index[i + j]].m[0]));
+
+				// Perform Q division and see which values need to be rewritten.
+				GSVector4 uv[n];
+				GSVector4 small{}, big{}, nan{};
+				for (int j = 0; j < n; j++)
+				{
+					// For sprites always use Q of second vertex.
+					const GSVector4 q = primclass == GS_SPRITE_CLASS ? stcq[1].wwww() : stcq[j].wwww();
+					uv[j] = (stcq[j] / q).xyzw(GSVector4::zero());
+					small |= (uv[j] <= -large_val);
+					big |= (uv[j] >= large_val);
+					nan |= (uv[j] != uv[j]);
+				}
+
+				// Get the new values for fields that will be rewritten.
+				// The follows rules are used:
+				// 1. If there are small values but not big or nans, make all vertices small.
+				// 2. If there are big values but not small or nans, make all vertices big.
+				// 3. If there are both big and small values, or nans, make all vertices zero.
+				GSVector4 uv_new = GSVector4::zero();
+				uv_new = uv_new.blend32(-large_val, small);
+				uv_new = uv_new.blend32(large_val, big);
+				uv_new = uv_new.blend32(GSVector4::zero(), (small & big) | nan);
+
+				const GSVector4 rewrite = (((small | big) & clamp_mask) | nan).xyxy(GSVector4::zero());
+
+				// If both S and T are rewritten, no point in keeping Q. Just set it to 1.0f;
+				if ((rewrite.mask() & 3) == 3)
+				{
+					for (int j = 0; j < n; j++)
+						stcq[j] = stcq[j].template insert32<0, 3>(GSVector4::m_one);
+				}
+
+				// Rewrite the fields that require it and write to the copy buffer.
+				for (int j = 0; j < n; j++)
+				{
+					// For sprites always use Q of second vertex.
+					const GSVector4 q = (primclass == GS_SPRITE_CLASS) ? stcq[1].wwww() : stcq[j].wwww();
+					stcq[j] = stcq[j].blend32(uv_new * q, rewrite);
+
+					vertex_copy[i + j].m[0] = GSVector4i::cast(stcq[j]);
+					vertex_copy[i + j].m[1] = vertex[index[i + j]].m[1];
+					index[i + j] = i + j;
+				}
+			}
+
+			// Swap the buffers and fix the counts.
+			std::swap(m_vertex->buff, m_vertex->buff_copy);
+			m_vertex->head = m_vertex->next = m_vertex->tail = m_index->tail;
+
+			// Recalculate ST min/max/eq in the vertex trace.
+			GSVector4 tmin = GSVector4::cxpr(FLT_MAX);
+			GSVector4 tmax = GSVector4::cxpr(-FLT_MAX);
+			for (int i = 0; i < count; i += n)
+			{
+				for (int j = 0; j < n; j++)
+				{
+					GSVector4 stcq = GSVector4::cast(GSVector4i(m_vertex->buff[i + j].m[0]));
+					const float q = (primclass == GS_SPRITE_CLASS) ? m_vertex->buff[i + 1].RGBAQ.Q : stcq.w;
+					stcq = (stcq / q).xyzw(stcq);
+
+					tmin = tmin.min(stcq);
+					tmax = tmax.max(stcq);
+				}
+			}
+			m_vt.m_min.t = tmin.xyww() * tsize;
+			m_vt.m_max.t = tmax.xyww() * tsize;
+			m_vt.m_eq.stq = (m_vt.m_min.t == m_vt.m_max.t).mask();
+
+			// Dump vertices if needed.
+			if (GSConfig.ShouldDump(s_n, g_perfmon.GetFrame()) && GSConfig.SaveInfo)
+			{
+				DumpVertices(GetDrawDumpPath("%05d_vertices_st_rewrite.txt", s_n));
+			}
+		}
+	}
+}
+
+void GSState::RewriteVerticesIfLargeST(const GSVector4& large_val, bool check_clamp_mode)
+{
+	switch (m_vt.m_primclass)
+	{
+		case GS_POINT_CLASS:
+			RewriteVerticesIfLargeSTImpl<GS_POINT_CLASS>(large_val, check_clamp_mode);
+			break;
+		case GS_LINE_CLASS:
+			RewriteVerticesIfLargeSTImpl<GS_LINE_CLASS>(large_val, check_clamp_mode);
+			break;
+		case GS_SPRITE_CLASS:
+			RewriteVerticesIfLargeSTImpl<GS_SPRITE_CLASS>(large_val, check_clamp_mode);
+			break;
+		case GS_TRIANGLE_CLASS:
+			RewriteVerticesIfLargeSTImpl<GS_TRIANGLE_CLASS>(large_val, check_clamp_mode);
+			break;
+		default:
+			pxFail("Invalid primclass"); // Impossible
+			break;
+	}
+}
+
 // GSTransferBuffer
 
 GSState::GSTransferBuffer::GSTransferBuffer()

pcsx2/GS/GSState.h

@@ -541,6 +541,9 @@ public:
 	bool SpriteDrawWithoutGaps();
 	void CalculatePrimitiveCoversWithoutGaps();
 	GIFRegTEX0 GetTex0Layer(u32 lod);
+	template <u32 primclass>
+	void RewriteVerticesIfLargeSTImpl(const GSVector4& large_val, bool check_clamp_mode);
+	void RewriteVerticesIfLargeST(const GSVector4& large_val, bool check_clamp_mode);
 };
 
 // We put this in the header because of Multi-ISA.

pcsx2/GS/Renderers/HW/GSRendererHW.cpp

@@ -2901,6 +2901,15 @@ void GSRendererHW::Draw()
 
 	// First pass texture shuffle detection using context/vertices.
 	DetectTextureShuffle();
+	
+	// Ridge Racer V and Destruction Derby Arena have large ST coordinates in reflection map draws that cause
+	// speckled artifacts on cars. Detect and rewrite such vertices here.
+	if (GSConfig.UserHacks_RewriteLargeST)
+	{
+		// The threshold is chosen to be low enough to fix the artifacts in Ridge Racer V and Destruction Derby Arena
+		// while not breaking anything.
+		RewriteVerticesIfLargeST(GSVector4::cxpr(16.0f), false);
+	}
 
 	// When the format is 24bit (Z or C), DATE ceases to function.
 	// It was believed that in 24bit mode all pixels pass because alpha doesn't exist
@@ -3526,13 +3535,14 @@ void GSRendererHW::Draw()
 		const u32 color_mask = (m_vt.m_max.c > GSVector4i::zero()).mask();
 		const bool texture_function_color = m_cached_ctx.TEX0.TFX == TFX_DECAL || (color_mask & 0xFFF) || (m_cached_ctx.TEX0.TFX > TFX_DECAL && (color_mask & 0xF000));
 		const bool texture_function_alpha = m_cached_ctx.TEX0.TFX != TFX_MODULATE || (color_mask & 0xF000);
-		const bool req_color = (is_possible_channel_shuffle && channel_shuffle_targets != ChannelFetch_ALPHA) || (!is_possible_channel_shuffle && ((texture_function_color && (!PRIM->ABE || GSLocalMemory::m_psm[m_cached_ctx.TEX0.PSM].bpp < 16 || (NeedsBlending() && IsUsingCsInBlend())) && (possible_shuffle || (m_cached_ctx.FRAME.FBMSK & (fm_mask & 0x00FFFFFF)) != (fm_mask & 0x00FFFFFF))) || need_aem_color));
-		const bool alpha_used = (GSUtil::GetChannelMask(m_context->TEX0.PSM) == 0x8 || (m_context->TEX0.TCC && texture_function_alpha)) && ((NeedsBlending() && IsUsingAsInBlend()) || (m_cached_ctx.TEST.ATE && m_cached_ctx.TEST.ATST > ATST_ALWAYS) || (possible_shuffle || (m_cached_ctx.FRAME.FBMSK & (fm_mask & 0xFF000000)) != (fm_mask & 0xFF000000)));
-		const bool req_alpha = (is_possible_channel_shuffle && channel_shuffle_targets == ChannelFetch_ALPHA) || (!is_possible_channel_shuffle && (GSUtil::GetChannelMask(m_context->TEX0.PSM) & 0x8) && alpha_used);
+		const bool color_used = (is_possible_channel_shuffle && channel_shuffle_targets != ChannelFetch_ALPHA) || (!is_possible_channel_shuffle && ((texture_function_color && (!PRIM->ABE || (NeedsBlending() && IsUsingCsInBlend())) && ((m_cached_ctx.FRAME.FBMSK & (fm_mask & 0x00FFFFFF)) != (fm_mask & 0x00FFFFFF))) || need_aem_color));
+		const bool alpha_used = (is_possible_channel_shuffle && channel_shuffle_targets == ChannelFetch_ALPHA) || (!is_possible_channel_shuffle && (m_context->TEX0.TCC && texture_function_alpha) && ((NeedsBlending() && IsUsingAsInBlend()) || (m_cached_ctx.TEST.ATE && m_cached_ctx.TEST.ATST > ATST_ALWAYS) || (m_cached_ctx.FRAME.FBMSK & (fm_mask & 0xFF000000)) != (fm_mask & 0xFF000000)));
+		const bool req_color = (GSUtil::GetChannelMask(m_context->TEX0.PSM) & 0x7) && color_used;
+		const bool req_alpha = (GSUtil::GetChannelMask(m_context->TEX0.PSM) == 0x8 && (color_used || alpha_used)) || ((GSUtil::GetChannelMask(m_context->TEX0.PSM) & 0x8) && alpha_used);
 
 		// TODO: Be able to send an alpha of 1.0 (blended with vertex alpha maybe?) so we can avoid sending the texture, since we don't always need it.
 		// Example games: Evolution Snowboarding, Final Fantasy Dirge of Cerberus, Red Dead Revolver, Stuntman, Tony Hawk's Underground 2, Ultimate Spider-Man.
-		if (!req_color && !alpha_used)
+		if (!req_color && !req_alpha)
 		{
 			m_process_texture = false;
 			possible_shuffle = false;

pcsx2/GS/Renderers/SW/GSRendererSW.cpp

@@ -287,125 +287,6 @@ void ConvertVertexBuffer(const GSDrawingContext* RESTRICT ctx, GSVertexSW* RESTR
 	}
 }
 
-// Fix ST coordinates that would overflow the rasterizer fixed point format by rewriting the vertices.
-template <u32 primclass>
-void GSRendererSW::RewriteVerticesIfSTOverflow()
-{
-	if (PRIM->TME && PRIM->FST == 0)
-	{
-		const GSVector4 tsize = GSVector4(
-			static_cast<float>(1 << m_context->TEX0.TW),
-			static_cast<float>(1 << m_context->TEX0.TH),
-			1.0f,
-			1.0f);
-
-		// SW rasterizer stores UV in 1.15.16 format so clamp to +/- (2^15 - 2) (-2 so bilinear doesn't overflow).
-		// Do the division by texture size here to avoid divisions for each vertex.
-		const GSVector4 OVERFLOW_VAL = GSVector4::cxpr(static_cast<float>((1 << 15) - 2)) / tsize;
-
-		// Only rewrite big/small S or T when the clamping mode is CLAMP or REGION_CLAMP.
-		const GSVector4i clamp_mode = GSVector4i(
-			(m_context->CLAMP.WMS == CLAMP_CLAMP || m_context->CLAMP.WMS == CLAMP_REGION_CLAMP) ? 0xFFFFFFFF : 0,
-			(m_context->CLAMP.WMT == CLAMP_CLAMP || m_context->CLAMP.WMT == CLAMP_REGION_CLAMP) ? 0xFFFFFFFF : 0,
-			0,
-			0);
-
-		const bool st_overflow =
-			((GSVector4i::cast(m_vt.m_min.t <= -OVERFLOW_VAL * tsize) & clamp_mode).mask() & 3) ||
-			((GSVector4i::cast(m_vt.m_max.t >= OVERFLOW_VAL * tsize) & clamp_mode).mask() & 3) ||
-			m_vt.nan.value;
-
-		if (st_overflow)
-		{
-			constexpr int n = GSUtil::GetClassVertexCount(primclass);
-
-			// Make sure the copy buffer is large enough.
-			while (m_max_vertex_count < m_index->tail)
-				GrowVertexBuffer();
-
-			GSVertex* RESTRICT vertex = m_vertex->buff;
-			GSVertex* RESTRICT vertex_copy = m_vertex->buff_copy;
-			u16* RESTRICT index = m_index->buff;
-
-			for (int i = 0; i < static_cast<int>(m_index->tail); i += n)
-			{
-				GSVector4 stcq[n];
-
-				// Load STQ for this primitive.
-				for (int j = 0; j < n; j++)
-					stcq[j] = GSVector4::cast(GSVector4i(vertex[index[i + j]].m[0]));
-
-				// Perform Q division and see which values need to be rewritten.
-				GSVector4 uv[n];
-				GSVector4i small{}, big{}, nan{};
-				for (int j = 0; j < n; j++)
-				{
-					// For sprites always use Q of second vertex.
-					const GSVector4 q = primclass == GS_SPRITE_CLASS ? stcq[1].wwww() : stcq[j].wwww();
-					uv[j] = (stcq[j] / q).xyzw(GSVector4::zero());
-					small |= GSVector4i::cast(uv[j] <= -OVERFLOW_VAL);
-					big |= GSVector4i::cast(uv[j] >= OVERFLOW_VAL);
-					nan |= GSVector4i::cast(uv[j] != uv[j]);
-				}
-
-				// Get the new values for fields that will be rewritten.
-				// The follows rules are used:
-				// 1. If there are small values but not big or nans, make all vertices small.
-				// 2. If there are big values but not small or nans, make all vertices big.
-				// 3. If there are both big and small values, or nans, make all vertices zero.
-				GSVector4 uv_new = GSVector4::zero();
-				uv_new = uv_new.blend32(-OVERFLOW_VAL, GSVector4::cast(small));
-				uv_new = uv_new.blend32(OVERFLOW_VAL, GSVector4::cast(big));
-				uv_new = uv_new.blend32(GSVector4::zero(), GSVector4::cast((small & big) | nan));
-
-				const GSVector4i rewrite = (((small | big) & clamp_mode) | nan).upl64(GSVector4i::zero());
-
-				// If both S and T are rewritten, no point in keeping Q. Just set it to 1.0f;
-				if ((GSVector4::cast(rewrite).mask() & 3) == 3)
-				{
-					for (int j = 0; j < n; j++)
-						stcq[j] = stcq[j].template insert32<0, 3>(GSVector4::m_one);
-				}
-				
-				// Rewrite the fields that require it and write to the copy buffer.
-				for (int j = 0; j < n; j++)
-				{
-					// For sprites always use Q of second vertex.
-					const GSVector4 q = (primclass == GS_SPRITE_CLASS) ? stcq[1].wwww() : stcq[j].wwww();
-					stcq[j] = stcq[j].blend32(uv_new * q, GSVector4::cast(rewrite));
-
-					vertex_copy[i + j].m[0] = GSVector4i::cast(stcq[j]);
-					vertex_copy[i + j].m[1] = vertex[index[i + j]].m[1];
-					index[i + j] = i + j;
-				}
-			}
-
-			// Swap the buffers and fix the counts.
-			std::swap(m_vertex->buff, m_vertex->buff_copy);
-			m_vertex->head = m_vertex->next = m_vertex->tail = m_index->tail;
-			
-			// Recalculate ST min/max/eq in the vertex trace.
-			GSVector4 tmin = GSVector4::cxpr(FLT_MAX);
-			GSVector4 tmax = GSVector4::cxpr(-FLT_MAX);
-			for (int i = 0; i < static_cast<int>(m_index->tail); i += n)
-			{
-				for (int j = 0; j < n; j++)
-				{
-					GSVector4 stcq = GSVector4::cast(GSVector4i(m_vertex->buff[i + j].m[0]));
-					const float Q = (primclass == GS_SPRITE_CLASS) ? stcq.w : m_vertex->buff[i + 1].RGBAQ.Q;
-					stcq = (stcq / Q).xyzw(stcq);
-					
-					tmin = tmin.min(stcq);
-					tmax = tmax.max(stcq);
-				}
-			}
-			m_vt.m_min.t = tmin.xyww() * tsize;
-			m_vt.m_max.t = tmax.xyww() * tsize;
-			m_vt.m_eq.stq = (m_vt.m_min.t == m_vt.m_max.t).mask();
-		}
-	}
-}
-
 void GSVertexSWInitStatic()
 {
 #define InitCVB4(P, T, F, Q) GSVertexSW::s_cvb[P][T][F][Q] = ConvertVertexBuffer<P, T, F, Q>;
@@ -427,24 +308,25 @@ MULTI_ISA_UNSHARED_END
 void GSRendererSW::Draw()
 {
 	const GSDrawingContext* context = m_context;
-
-	switch (m_vt.m_primclass)
+	if (!GSConfig.UserHacks_RewriteLargeST)
 	{
-		case GS_POINT_CLASS:
-			RewriteVerticesIfSTOverflow<GS_POINT_CLASS>();
-			break;
-		case GS_LINE_CLASS:
-			RewriteVerticesIfSTOverflow<GS_LINE_CLASS>();
-			break;
-		case GS_TRIANGLE_CLASS:
-			RewriteVerticesIfSTOverflow<GS_TRIANGLE_CLASS>();
-			break;
-		case GS_SPRITE_CLASS:
-			RewriteVerticesIfSTOverflow<GS_SPRITE_CLASS>();
-			break;
-		default:
-			pxFailRel("Unknown primitive class.");
-			break;
+		// SW rasterizer stores UV in 1.15.16 format so clamp to +/- (2^15 - 2) (-2 so bilinear doesn't overflow).
+		// Also only do this for CLAMP and CLAMP_REGION modes to reduce the performance impact.
+		const GSVector4 tsize = GSVector4(
+			static_cast<float>(1 << m_context->TEX0.TW),
+			static_cast<float>(1 << m_context->TEX0.TH),
+			1.0f,
+			1.0f);
+
+		// Large value is given in terms of normalized ST / Q coordinates.
+		const GSVector4 large_val = GSVector4::cxpr(static_cast<float>((1 << 15) - 2)) / tsize;
+		RewriteVerticesIfLargeST(large_val, true);
+	}
+	else
+	{
+		// More sensitive as the rewrite threshold is lower and we do it for all clamp mode.
+		// The performance cost will also be higher.
+		RewriteVerticesIfLargeST(GSVector4::cxpr(16.0f), false);
 	}
 	
 	auto data = m_vertex_heap.make_shared<SharedData>().cast<GSRasterizerData>();

pcsx2/GameDatabase.cpp

@@ -376,6 +376,7 @@ static const char* s_gs_hw_fix_names[] = {
 	"nativePaletteDraw",
 	"estimateTextureRegion",
 	"drawBuffering",
+	"rewriteLargeST",
 	"PCRTCOffsets",
 	"PCRTCOverscan",
 	"trilinearFiltering",
@@ -622,6 +623,9 @@ bool GameDatabaseSchema::GameEntry::configMatchesHWFix(const Pcsx2Config::GSOpti
 
 		case GSHWFixId::DrawBuffering:
 			return (static_cast<int>(config.UserHacks_DrawBuffering) == value);
+		
+		case GSHWFixId::RewriteLargeST:
+			return (static_cast<int>(config.UserHacks_RewriteLargeST) == value);
 
 		case GSHWFixId::PCRTCOffsets:
 			return (static_cast<int>(config.PCRTCOffsets) == value);
@@ -793,6 +797,10 @@ void GameDatabaseSchema::GameEntry::applyGSHardwareFixes(Pcsx2Config::GSOptions&
 				config.UserHacks_DrawBuffering = (value > 0);
 				break;
 
+			case GSHWFixId::RewriteLargeST:
+				config.UserHacks_RewriteLargeST = (value > 0);
+				break;
+
 			case GSHWFixId::PCRTCOffsets:
 				config.PCRTCOffsets = (value > 0);
 				break;

pcsx2/GameDatabase.h

@@ -61,6 +61,7 @@ namespace GameDatabaseSchema
 		NativePaletteDraw,
 		EstimateTextureRegion,
 		DrawBuffering,
+		RewriteLargeST,
 		PCRTCOffsets,
 		PCRTCOverscan,
 

pcsx2/ImGui/FullscreenUI_Settings.cpp

@@ -3236,6 +3236,9 @@ void FullscreenUI::DrawGraphicsSettingsPage(SettingsInterface* bsi, bool show_ad
 			DrawToggleSetting(bsi, FSUI_ICONSTR(ICON_FA_CROP, "Estimate Texture Region"),
 				FSUI_CSTR("Attempts to reduce the texture size when games do not set it themselves (e.g. Snowblind games)."), "EmuCore/GS",
 				"UserHacks_EstimateTextureRegion", false, manual_hw_fixes);
+			DrawToggleSetting(bsi, FSUI_CSTR("Rewrite Large ST"),
+				FSUI_CSTR("Rewrite large ST coordinates and clamp the values."), "EmuCore/GS",
+				"UserHacks_RewriteLargeST", false, manual_hw_fixes);
 			DrawToggleSetting(bsi, FSUI_ICONSTR(ICON_FA_PALETTE, "GPU Palette Conversion"),
 				FSUI_CSTR("When enabled GPU converts colormap-textures, otherwise the CPU will. It is a trade-off between GPU and CPU."),
 				"EmuCore/GS", "paltex", false, manual_hw_fixes);

pcsx2/ImGui/ImGuiOverlays.cpp

@@ -1021,6 +1021,8 @@ __ri void ImGuiManager::DrawSettingsOverlay(float scale, float margin, float spa
 			APPEND("ETR ");
 		if (GSConfig.UserHacks_DrawBuffering)
 			APPEND("DRWB ");
+		if (GSConfig.UserHacks_RewriteLargeST)
+			APPEND("RWST ");
 		if (GSConfig.HWSpinGPUForReadbacks)
 			APPEND("RBSG ");
 		if (GSConfig.HWSpinCPUForReadbacks)

pcsx2/Pcsx2Config.cpp

@@ -1005,6 +1005,7 @@ void Pcsx2Config::GSOptions::LoadSave(SettingsWrapper& wrap)
 	SettingsWrapIntEnumEx(UserHacks_Limit24BitDepth, "UserHacks_Limit24BitDepth");
 	SettingsWrapBitBoolEx(UserHacks_EstimateTextureRegion, "UserHacks_EstimateTextureRegion");
 	SettingsWrapBitBoolEx(UserHacks_DrawBuffering, "UserHacks_DrawBuffering");
+	SettingsWrapBitBoolEx(UserHacks_RewriteLargeST, "UserHacks_RewriteLargeST");
 	SettingsWrapBitBoolEx(FXAA, "fxaa");
 	SettingsWrapBitBool(ShadeBoost);
 	SettingsWrapBitBoolEx(DumpGSData, "DumpGSData");
@@ -1145,6 +1146,7 @@ void Pcsx2Config::GSOptions::MaskUserHacks()
 	UserHacks_Limit24BitDepth = GSLimit24BitDepth::Disabled;
 	UserHacks_EstimateTextureRegion = false;
 	UserHacks_DrawBuffering = false;
+	UserHacks_RewriteLargeST = false;
 	UserHacks_TCOffsetX = 0;
 	UserHacks_TCOffsetY = 0;
 	UserHacks_CPUSpriteRenderBW = 0;

pcsx2/VMManager.cpp

@@ -3279,6 +3279,11 @@ void VMManager::WarnAboutUnsafeSettings()
 			append(ICON_FA_CIRCLE_EXCLAMATION,
 				TRANSLATE_SV("VMManager", "Draw Buffering is enabled, this may result in graphical errors."));
 		}
+		if (EmuConfig.GS.UserHacks_RewriteLargeST)
+		{
+			append(ICON_FA_CIRCLE_EXCLAMATION,
+				TRANSLATE_SV("VMManager", "Rewrite large ST is enabled, this may reduce performance."));
+		}
 		if (EmuConfig.GS.DumpReplaceableTextures)
 		{
 			append(ICON_FA_CIRCLE_EXCLAMATION,