GS/HW: Adjust line AA1 blur with upscaling.

bin/resources/shaders/dx11/tfx.fx

@@ -290,6 +290,12 @@ cbuffer cb1
 	float4x4 DitherMatrix;
 	float ScaledScaleFactor;
 	float RcpScaleFactor;
+	float _pad0_cb1;
+	float _pad1_cb1;
+	float LineCovScale;
+	float _pad2_cb1;
+	float _pad3_cb1;
+	float _pad4_cb1;
 };
 
 float4 RtLoad(int2 xy)
@@ -1362,7 +1368,12 @@ void ps_main(PS_INPUT input)
 	float4 C = ps_color(input);
 
 #if PS_AA1
-	float cov = clamp(1.0f - abs(input.inv_cov), 0.0f, 1.0f);
+	#if PS_AA1 == PS_AA1_LINE
+		// Blur only outer part of the line by scaling coverage.
+		float cov = clamp(LineCovScale * (1.0f - abs(input.inv_cov)), 0.0f, 1.0f);
+	#else
+		float cov = clamp(1.0f - abs(input.inv_cov), 0.0f, 1.0f);
+	#endif
 	#if PS_ABE
 		if (floor(C.a) == 128.0f) // The coverage is only used if the fragment alpha is 128.
 			C.a = 128.0f * cov;
@@ -1632,7 +1643,7 @@ cbuffer cb0
 	float2 TextureOffset;
 	float2 PointSize;
 	uint MaxDepth;
-	uint _cb0_pad0;
+	float LineAA1Width;
 };
 
 #ifdef DX12
@@ -1875,11 +1886,9 @@ VS_OUTPUT vs_main_expand(uint vid : SV_VertexID)
 	// Use bottom minus top for delta regardless of which vertex we are expanding.
 	float2 line_delta = is_bottom ? (vtx.p.xy - other.p.xy) : (other.p.xy - vtx.p.xy);
 	float2 line_vector = normalize(line_delta / VertexScale);
-#if VS_EXPAND == VS_EXPAND_LINE
 	float2 line_expand = float2(line_vector.y, -line_vector.x);
-#elif VS_EXPAND == VS_EXPAND_LINE_AA1
+#if VS_EXPAND == VS_EXPAND_LINE_AA1
-	// Expand in y direction for shallow lines and x direction for steep lines.
+	line_expand *= 2.0f * LineAA1Width;
-	float2 line_expand = abs(line_vector.x) >= abs(line_vector.y) ? float2(0.0f, 2.0f) : float2(2.0f, 0.0f);
 #endif
 	float2 line_width = (line_expand * PointSize) / 2;
 	float2 offset = is_right ? line_width : -line_width;

bin/resources/shaders/opengl/tfx_fs.glsl

@@ -93,6 +93,13 @@ layout(std140, binding = 0) uniform cb21
 
 	float ScaledScaleFactor;
 	float RcpScaleFactor;
+	float _pad0_cb1;
+	float _pad1_cb1;
+
+	float LineCovScale;
+	float _pad2_cb1;
+	float _pad3_cb1;
+	float _pad4_cb1;
 };
 
 in SHADER
@@ -1250,7 +1257,12 @@ void ps_main()
 	vec4 C = ps_color();
 
 #if PS_AA1
-	float cov = clamp(1.0f - abs(PSin.inv_cov), 0.0f, 1.0f);
+	#if PS_AA1 == PS_AA1_LINE
+		// Blur only outer part of the line by scaling coverage.
+		float cov = clamp(LineCovScale * (1.0f - abs(PSin.inv_cov)), 0.0f, 1.0f);
+	#else
+		float cov = clamp(1.0f - abs(PSin.inv_cov), 0.0f, 1.0f);
+	#endif
 	#if PS_ABE
 		if (floor(C.a) == 128.0f) // The coverage is only used if the fragment alpha is 128.
 			C.a = 128.0f * cov;

bin/resources/shaders/opengl/tfx_vgs.glsl

@@ -12,8 +12,9 @@ layout(std140, binding = 1) uniform cb20
 	vec2  TextureOffset;
 
 	vec2  PointSize;
+
 	uint  MaxDepth;
-	uint  pad_cb20;
+	float LineAA1Width;
 };
 
 #ifdef VERTEX_SHADER
@@ -323,11 +324,8 @@ void main()
 	// Use bottom minus top for delta regardless of which vertex we are expanding.
 	vec2 line_delta = is_bottom ? (vtx.p.xy - other.p.xy) : (other.p.xy - vtx.p.xy);
 	vec2 line_vector = normalize(line_delta / VertexScale);
-#if VS_EXPAND == VS_EXPAND_LINE
+if VS_EXPAND == VS_EXPAND_LINE_AA1
-	vec2 line_expand = vec2(line_vector.y, -line_vector.x);
+	line_expand *= 2.0f * LineAA1Width;
-#elif VS_EXPAND == VS_EXPAND_LINE_AA1
-	// Expand in y direction for shallow lines and x direction for steep lines.
-	vec2 line_expand = abs(line_vector.x) >= abs(line_vector.y) ? vec2(0.0f, 2.0f) : vec2(2.0f, 0.0f);
 #endif
 	vec2 line_width = (line_expand * PointSize) / 2;
 	vec2 offset = is_right ? line_width : -line_width;

bin/resources/shaders/vulkan/tfx.glsl

@@ -24,7 +24,7 @@ layout(std140, set = 0, binding = 0) uniform cb0
 	vec2 TextureOffset;
 	vec2 PointSize;
 	uint MaxDepth;
-	uint pad_cb0;
+	float LineAA1Width;
 };
 
 layout(location = 0) out VSOutput
@@ -319,11 +319,9 @@ void main()
 	// Use bottom minus top for delta regardless of which vertex we are expanding.
 	vec2 line_delta = is_bottom ? (vtx.p.xy - other.p.xy) : (other.p.xy - vtx.p.xy);
 	vec2 line_vector = normalize(line_delta / VertexScale);
-#if VS_EXPAND == VS_EXPAND_LINE
 	vec2 line_expand = vec2(line_vector.y, -line_vector.x);
-#elif VS_EXPAND == VS_EXPAND_LINE_AA1
+#if VS_EXPAND == VS_EXPAND_LINE_AA1
-	// Expand in y direction for shallow lines and x direction for steep lines.
+	line_expand *= 2.0f * LineAA1Width;
-	vec2 line_expand = abs(line_vector.x) >= abs(line_vector.y) ? vec2(0.0f, 2.0f) : vec2(2.0f, 0.0f);
 #endif
 	vec2 line_width = (line_expand * PointSize) / 2;
 	vec2 offset = is_right ? line_width : -line_width;
@@ -624,6 +622,12 @@ layout(std140, set = 0, binding = 1) uniform cb1
 	mat4 DitherMatrix;
 	float ScaledScaleFactor;
 	float RcpScaleFactor;
+	float _pad0_cb1;
+	float _pad1_cb1;
+	float LineCovScale;
+	float _pad2_cb1;
+	float _pad3_cb1;
+	float _pad4_cb1;
 };
 
 layout(location = 0) in VSOutput
@@ -1804,7 +1808,12 @@ void main()
 	vec4 C = ps_color();
 
 #if PS_AA1
-	float cov = clamp(1.0f - abs(vsIn.inv_cov), 0.0f, 1.0f);
+	#if PS_AA1 == PS_AA1_LINE
+		// Blur only outer part of the line by scaling coverage.
+		float cov = clamp(LineCovScale * (1.0f - abs(vsIn.inv_cov)), 0.0f, 1.0f);
+	#else
+		float cov = clamp(1.0f - abs(vsIn.inv_cov), 0.0f, 1.0f);
+	#endif
 	#if PS_ABE
 		if (floor(C.a) == 128.0f) // The coverage is only used if the fragment alpha is 128.
 			C.a = 128.0f * cov;

pcsx2/GS/Renderers/Common/GSDevice.cpp

@@ -1705,6 +1705,7 @@ static void DumpPSConstantBuffer(DrawConfigWriter& out, const GSHWDrawConfig::PS
 	DumpVector4(out, "DitherMatrix_2", cb.DitherMatrix[2]);
 	DumpVector4(out, "DitherMatrix_3", cb.DitherMatrix[3]);
 	DumpVector4(out, "ScaleFactor", cb.ScaleFactor);
+	out.WriteLn("LineCovScale: {}", cb.LineCovScale);
 }
 
 static void DumpVSConstantBuffer(DrawConfigWriter& out, const GSHWDrawConfig::VSConstantBuffer& cb)
@@ -1714,7 +1715,8 @@ static void DumpVSConstantBuffer(DrawConfigWriter& out, const GSHWDrawConfig::VS
 	DumpVector2(out, "texture_scale", cb.texture_scale);
 	DumpVector2(out, "texture_offset", cb.texture_offset);
 	DumpVector2(out, "point_size", cb.point_size);
-	DumpVector2(out, "max_depth", cb.max_depth);
+	out.WriteLn("max_depth: {}", cb.max_depth);
+	out.WriteLn("line_aa1_width: {}", cb.line_aa1_width);
 }
 
 static void DumpConfig(DrawConfigWriter& out, const GSHWDrawConfig& conf,

pcsx2/GS/Renderers/Common/GSDevice.h

@@ -1027,7 +1027,8 @@ struct alignas(16) GSHWDrawConfig
 		GSVector2 texture_scale;
 		GSVector2 texture_offset;
 		GSVector2 point_size;
-		GSVector2i max_depth;
+		u32 max_depth;
+		float line_aa1_width;
 		__fi VSConstantBuffer()
 		{
 			memset(static_cast<void*>(this), 0, sizeof(*this));
@@ -1117,6 +1118,10 @@ struct alignas(16) GSHWDrawConfig
 		GSVector4 DitherMatrix[4];
 
 		GSVector4 ScaleFactor;
+		float LineCovScale;
+		float _pad0;
+		float _pad1;
+		float _pad2;
 
 		__fi PSConstantBuffer()
 		{

pcsx2/GS/Renderers/HW/GSRendererHW.cpp

@@ -5442,6 +5442,25 @@ void GSRendererHW::SetupIA(float target_scale, float sx, float sy, bool req_vert
 					GL_INS("HW: AA1 line expand.");
 					m_conf.vs.expand = GSHWDrawConfig::VSExpand::LineAA1;
 					m_conf.cb_vs.point_size = GSVector2(16.0f * sx, 16.0f * sy);
+
+					if (target_scale == 1.0f)
+					{
+						m_conf.cb_vs.line_aa1_width = 1.0f; // 1 native pixel on each side.
+						m_conf.cb_ps.LineCovScale = 1.0f; // Linear falloff on both sides.
+					}
+					else
+					{
+						// Reduce the amount of blur with upscaling.
+						constexpr float half_native_px = 0.5f;
+						const float upscaled_px = 1.0f / target_scale;
+
+						// Half a native pixel + 1 upscaled pixel on both sides.
+						m_conf.cb_vs.line_aa1_width = half_native_px + upscaled_px;
+
+						// Opaque in middle and linear falloff on last 2 upscaled pixels on each side.
+						m_conf.cb_ps.LineCovScale = (half_native_px + upscaled_px) / (2 * upscaled_px); 
+					}
+
 					m_conf.topology = GSHWDrawConfig::Topology::Triangle;
 					m_conf.indices_per_prim = 6;
 					ExpandLineIndices();
@@ -5583,7 +5602,7 @@ void GSRendererHW::EmulateZbuffer(const GSTextureCache::Target* ds)
 	// No interpolation for flat Z so we can make some optimizations.
 	const bool flat_z = m_vt.m_eq.z || m_vt.m_primclass == GS_POINT_CLASS || m_vt.m_primclass == GS_SPRITE_CLASS;
 
-	m_conf.cb_vs.max_depth = GSVector2i(0xFFFFFFFF);
+	m_conf.cb_vs.max_depth = 0xFFFFFFFF;
 	m_conf.cb_ps.TA_MaxDepth_Af.z = 0.0f;
 	m_conf.ps.zclamp = false;
 
@@ -5597,7 +5616,7 @@ void GSRendererHW::EmulateZbuffer(const GSTextureCache::Target* ds)
 		if (flat_z)
 		{
 			// Clamp in vertex shader.
-			m_conf.cb_vs.max_depth = GSVector2i(max_z);
+			m_conf.cb_vs.max_depth = max_z;
 		}
 		else
 		{

pcsx2/GS/Renderers/Metal/GSMTLSharedHeader.h

@@ -98,7 +98,7 @@ struct GSMTLMainVSUniform
 	vector_float2 texture_offset;
 	vector_float2 point_size;
 	uint max_depth;
-	uint _pad0;
+	float line_aa1_width;
 };
 
 struct GSMTLMainPSUniform
@@ -140,6 +140,11 @@ struct GSMTLMainPSUniform
 	matrix_float4x4 dither_matrix;
 
 	vector_float4 scale_factor;
+
+	float line_cov_scale;
+	float _pad0;
+	float _pad1;
+	float _pad2;
 };
 
 enum GSMTLAttributes

pcsx2/GS/Renderers/Metal/tfx.metal

@@ -398,16 +398,11 @@ vertex MainVSOut vs_main_expand(
 			// Use bottom minus top for delta regardless of which vertex we are expanding.
 			float2 line_delta = is_bottom ? point.p.xy - other.p.xy : other.p.xy - point.p.xy;
 			float2 line_vector = normalize(line_delta / cb.vertex_scale);
-			float2 line_expand;
+			float2 line_expand = float2(line_vector.y, -line_vector.x);
-			if (VS_EXPAND_TYPE == VSExpand::Line)
+
-			{
+			if (VS_EXPAND_TYPE == VSExpand::LineAA1)
-				line_expand = float2(line_vector.y, -line_vector.x);
+				line_expand *= 2.f * cb.line_aa1_width;
-			}
+
-			else
-			{
-				// Expand in y direction for shallow lines and x direction for steep lines.
-				line_expand = abs(line_vector.x) >= abs(line_vector.y) ? float2(0, 2) : float2(2, 0);
-			}
 			float2 line_width = (line_expand * cb.point_size) / 2;
 			float2 offset = is_right ? line_width : -line_width;
 			point.p.xy += offset;
@@ -1507,7 +1502,9 @@ struct PSMain
 
 		if (PS_AA1 != AA1::NONE)
 		{
-			float cov = saturate(1.f - abs(in.inv_cov));
+			float cov = PS_AA1 == AA1::LINE ?
+				saturate(cb.line_cov_scale * (1.f - abs(in.inv_cov))) : // Blur only outer part of the line by scaling coverage.
+			  saturate(1.f - abs(in.inv_cov));
 			if (!PS_ABE || floor(C.a) == 128.f) // The coverage is only used if the fragment alpha is 128.
 				C.a = 128.f * cov;
 		}

pcsx2/ShaderCacheVersion.h

@@ -3,4 +3,4 @@
 
 /// Version number for GS and other shaders. Increment whenever any of the contents of the
 /// shaders change, to invalidate the cache.
-static constexpr u32 SHADER_CACHE_VERSION = 101; // Last changed in PR 14547
+static constexpr u32 SHADER_CACHE_VERSION = 102; // Last changed in PR 14480