URP 2D Lit Smooth Pixel Scaling

JitterFreeLit.shader

Shader "Sprites/JitterFreeLit"
{
	Properties
	{
		_MainTex("Diffuse", 2D) = "white" {}
		_MaskTex("Mask", 2D) = "white" {}
		_NormalMap("Normal Map", 2D) = "bump" {}

		// Legacy properties. They're here so that materials using this shader can gracefully fallback to the legacy sprite shader.
		[HideInInspector] _Color("Tint", Color) = (1,1,1,1)
		[HideInInspector] _RendererColor("RendererColor", Color) = (1,1,1,1)
		[HideInInspector] _Flip("Flip", Vector) = (1,1,1,1)
		[HideInInspector] _AlphaTex("External Alpha", 2D) = "white" {}
		[HideInInspector] _EnableExternalAlpha("Enable External Alpha", Float) = 0
	}

	SubShader
	{
		Tags {"Queue" = "Transparent" "RenderType" = "Transparent" "RenderPipeline" = "UniversalPipeline" }

		Blend SrcAlpha OneMinusSrcAlpha, One OneMinusSrcAlpha
		Cull Off
		ZWrite Off

		Pass
		{
			Tags { "LightMode" = "Universal2D" }

			HLSLPROGRAM
			#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"

			#pragma vertex CombinedShapeLightVertex
			#pragma fragment CombinedShapeLightFragment

			#pragma multi_compile USE_SHAPE_LIGHT_TYPE_0 __
			#pragma multi_compile USE_SHAPE_LIGHT_TYPE_1 __
			#pragma multi_compile USE_SHAPE_LIGHT_TYPE_2 __
			#pragma multi_compile USE_SHAPE_LIGHT_TYPE_3 __
			#pragma multi_compile _ DEBUG_DISPLAY

			struct Attributes
			{
				float3 positionOS   : POSITION;
				float4 color        : COLOR;
				float2  uv          : TEXCOORD0;
				UNITY_VERTEX_INPUT_INSTANCE_ID
			};

			struct Varyings
			{
				float4  positionCS  : SV_POSITION;
				half4   color       : COLOR;
				float2  uv          : TEXCOORD0;
				half2   lightingUV  : TEXCOORD1;
				#if defined(DEBUG_DISPLAY)
				float3  positionWS  : TEXCOORD2;
				#endif
				UNITY_VERTEX_OUTPUT_STEREO
			};

			#include "Packages/com.unity.render-pipelines.universal/Shaders/2D/Include/LightingUtility.hlsl"

			//TEXTURE2D(_MainTex);
			//SAMPLER(sampler_MainTex);
			TEXTURE2D(_MaskTex);
			SAMPLER(sampler_MaskTex);
			sampler2D _MainTex;
			half4 _MainTex_ST;
			float4 _MainTex_TexelSize;

			#if USE_SHAPE_LIGHT_TYPE_0
			SHAPE_LIGHT(0)
			#endif

			#if USE_SHAPE_LIGHT_TYPE_1
			SHAPE_LIGHT(1)
			#endif

			#if USE_SHAPE_LIGHT_TYPE_2
			SHAPE_LIGHT(2)
			#endif

			#if USE_SHAPE_LIGHT_TYPE_3
			SHAPE_LIGHT(3)
			#endif

			Varyings CombinedShapeLightVertex(Attributes v)
			{
				Varyings o = (Varyings)0;
				UNITY_SETUP_INSTANCE_ID(v);
				UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);

				o.positionCS = TransformObjectToHClip(v.positionOS);
				#if defined(DEBUG_DISPLAY)
				o.positionWS = TransformObjectToWorld(v.positionOS);
				#endif
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				o.lightingUV = half2(ComputeScreenPos(o.positionCS / o.positionCS.w).xy);

				o.color = v.color;
				return o;
			}

			#include "Packages/com.unity.render-pipelines.universal/Shaders/2D/Include/CombinedShapeLightShared.hlsl"

			float4 texturePointSmooth(sampler2D tex, float2 uvs)
			{
				float2 size;
				size.x = _MainTex_TexelSize.z;
				size.y = _MainTex_TexelSize.w;

				float2 pixel = float2(1.0,1.0) / size;

				uvs -= pixel * float2(0.5,0.5);
				float2 uv_pixels = uvs * size;
				float2 delta_pixel = frac(uv_pixels) - float2(0.5,0.5);

				float2 ddxy = fwidth(uv_pixels);
				float2 mip = log2(ddxy) - 0.5;

				float2 clampedUV = uvs + (clamp(delta_pixel / ddxy, 0.0, 1.0) - delta_pixel) * pixel;
				return tex2Dlod(tex, float4(clampedUV,0, min(mip.x, mip.y)));
			}

			half4 CombinedShapeLightFragment(Varyings i) : SV_Target
			{
				//const half4 main = i.color * SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.uv);
				const half4 main = i.color * texturePointSmooth(_MainTex, i.uv);
				//const half4 mask = SAMPLE_TEXTURE2D(_MaskTex, sampler_MaskTex, i.uv);
				const half4 mask = texturePointSmooth(_MainTex, i.uv);
				SurfaceData2D surfaceData;
				InputData2D inputData;

				InitializeSurfaceData(main.rgb, main.a, mask, surfaceData);
				InitializeInputData(i.uv, i.lightingUV, inputData);

				return CombinedShapeLightShared(surfaceData, inputData);
			}
			ENDHLSL
		}

		Pass
		{
			Tags { "LightMode" = "NormalsRendering"}

			HLSLPROGRAM
			#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"

			#pragma vertex NormalsRenderingVertex
			#pragma fragment NormalsRenderingFragment

			struct Attributes
			{
				float3 positionOS   : POSITION;
				float4 color        : COLOR;
				float2 uv           : TEXCOORD0;
				float4 tangent      : TANGENT;
				UNITY_VERTEX_INPUT_INSTANCE_ID
			};

			struct Varyings
			{
				float4  positionCS      : SV_POSITION;
				half4   color           : COLOR;
				float2  uv              : TEXCOORD0;
				half3   normalWS        : TEXCOORD1;
				half3   tangentWS       : TEXCOORD2;
				half3   bitangentWS     : TEXCOORD3;
				UNITY_VERTEX_OUTPUT_STEREO
			};

			TEXTURE2D(_MainTex);
			SAMPLER(sampler_MainTex);
			TEXTURE2D(_NormalMap);
			SAMPLER(sampler_NormalMap);
			half4 _NormalMap_ST;  // Is this the right way to do this?
			float4 _MainTex_TexelSize;

			Varyings NormalsRenderingVertex(Attributes attributes)
			{
				Varyings o = (Varyings)0;
				UNITY_SETUP_INSTANCE_ID(attributes);
				UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);

				o.positionCS = TransformObjectToHClip(attributes.positionOS);
				o.uv = TRANSFORM_TEX(attributes.uv, _NormalMap);
				o.color = attributes.color;
				o.normalWS = -GetViewForwardDir();
				o.tangentWS = TransformObjectToWorldDir(attributes.tangent.xyz);
				o.bitangentWS = cross(o.normalWS, o.tangentWS) * attributes.tangent.w;
				return o;
			}

			#include "Packages/com.unity.render-pipelines.universal/Shaders/2D/Include/NormalsRenderingShared.hlsl"

			half4 NormalsRenderingFragment(Varyings i) : SV_Target
			{
				const half4 mainTex = i.color * SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.uv);
				const half3 normalTS = UnpackNormal(SAMPLE_TEXTURE2D(_NormalMap, sampler_NormalMap, i.uv));

				return NormalsRenderingShared(mainTex, normalTS, i.tangentWS.xyz, i.bitangentWS.xyz, i.normalWS.xyz);
			}
			ENDHLSL
		}

		Pass
		{
			Tags { "LightMode" = "UniversalForward" "Queue"="Transparent" "RenderType"="Transparent"}

			HLSLPROGRAM
			#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"

			#pragma vertex UnlitVertex
			#pragma fragment UnlitFragment

			struct Attributes
			{
				float3 positionOS   : POSITION;
				float4 color        : COLOR;
				float2 uv           : TEXCOORD0;
				UNITY_VERTEX_INPUT_INSTANCE_ID
			};

			struct Varyings
			{
				float4  positionCS      : SV_POSITION;
				float4  color           : COLOR;
				float2  uv              : TEXCOORD0;
				#if defined(DEBUG_DISPLAY)
				float3  positionWS  : TEXCOORD2;
				#endif
				UNITY_VERTEX_OUTPUT_STEREO
			};

			TEXTURE2D(_MainTex);
			SAMPLER(sampler_MainTex);
			float4 _MainTex_ST;
			float4 _MainTex_TexelSize;

			Varyings UnlitVertex(Attributes attributes)
			{
				Varyings o = (Varyings)0;
				UNITY_SETUP_INSTANCE_ID(attributes);
				UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);

				o.positionCS = TransformObjectToHClip(attributes.positionOS);
				#if defined(DEBUG_DISPLAY)
				o.positionWS = TransformObjectToWorld(v.positionOS);
				#endif
				o.uv = TRANSFORM_TEX(attributes.uv, _MainTex);
				o.color = attributes.color;
				return o;
			}

			float4 UnlitFragment(Varyings i) : SV_Target
			{
				float4 mainTex = i.color * SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.uv);

				#if defined(DEBUG_DISPLAY)
				SurfaceData2D surfaceData;
				InputData2D inputData;
				half4 debugColor = 0;

				InitializeSurfaceData(mainTex.rgb, mainTex.a, surfaceData);
				InitializeInputData(i.uv, inputData);
				SETUP_DEBUG_DATA_2D(inputData, i.positionWS);

				if(CanDebugOverrideOutputColor(surfaceData, inputData, debugColor))
				{
					return debugColor;
				}
				#endif

				return mainTex;
			}
			ENDHLSL
		}
	}

	Fallback "Sprites/Default"
}

You can also do a ShaderGraph version by just running the _MainTex and UV through the custom function.

float2 size;
size.x = _MainTex_TexelSize.z;
size.y = _MainTex_TexelSize.w;

float2 pixel = float2(1.0,1.0) / size;

uvs -= pixel * float2(0.5,0.5);
float2 uv_pixels = uvs * size;
float2 delta_pixel = frac(uv_pixels) - float2(0.5,0.5);

float2 ddxy = fwidth(uv_pixels);
float2 mip = log2(ddxy) - 0.5;

float2 clampedUV = uvs + (clamp(delta_pixel / ddxy, 0.0, 1.0) - delta_pixel) * pixel;
_out = tex2Dlod(tex, float4(clampedUV,0, min(mip.x, mip.y)));

Thank you very much! I was looking for this shader for a while, but all what i found was either unlit shader or code implementation. Your custom function turned out to be the best option for me! ⭐