77 lines
3.0 KiB
Plaintext
77 lines
3.0 KiB
Plaintext
Shader "SLS/Postprocessing/Sharpen"
|
||
{
|
||
SubShader
|
||
{
|
||
Tags
|
||
{
|
||
"RenderType" = "Opaque"
|
||
"RenderPipeline" = "UniversalPipeline"
|
||
}
|
||
ZWrite Off
|
||
Cull Off
|
||
|
||
HLSLINCLUDE
|
||
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"
|
||
#include "Packages/com.unity.render-pipelines.core/Runtime/Utilities/Blit.hlsl"
|
||
|
||
// 变量定义
|
||
float4 _SharpnessParams;
|
||
// x: Strength (锐化强度)
|
||
// y: Threshold (对比度阈值，用于降噪)
|
||
// z: Clamp (最大亮度变化限制，防光晕)
|
||
// w: Unused
|
||
|
||
half4 SharpenPassFragment(Varyings input) : SV_Target
|
||
{
|
||
half2 uv = input.texcoord;
|
||
// _BlitTexture_TexelSize 包含了纹理像素的大小 (1/width, 1/height)
|
||
float4 texelSize = _BlitTexture_TexelSize;
|
||
|
||
// 1. 5-Tap 采样 (中心 + 上下左右)
|
||
half4 center = SAMPLE_TEXTURE2D_X(_BlitTexture, sampler_LinearClamp, uv);
|
||
half3 up = SAMPLE_TEXTURE2D_X(_BlitTexture, sampler_LinearClamp, uv + float2(0, texelSize.y)).rgb;
|
||
half3 down = SAMPLE_TEXTURE2D_X(_BlitTexture, sampler_LinearClamp, uv - float2(0, texelSize.y)).rgb;
|
||
half3 left = SAMPLE_TEXTURE2D_X(_BlitTexture, sampler_LinearClamp, uv - float2(texelSize.x, 0)).rgb;
|
||
half3 right = SAMPLE_TEXTURE2D_X(_BlitTexture, sampler_LinearClamp, uv + float2(texelSize.x, 0)).rgb;
|
||
|
||
// 2. 计算周围像素的平均值
|
||
half3 neighborsAvg = (up + down + left + right) * 0.25;
|
||
|
||
// 3. 计算差异 (边缘信号)
|
||
// 如果 center 比周围亮，diff 为正；反之为负。
|
||
half3 diff = center.rgb - neighborsAvg;
|
||
|
||
// 参数解包
|
||
float strength = _SharpnessParams.x;
|
||
float threshold = _SharpnessParams.y;
|
||
float clampVal = _SharpnessParams.z;
|
||
|
||
// 4. 【优化一】对比度阈值 (Threshold) - 降噪用
|
||
// 计算差异的亮度值
|
||
float lumaDiff = dot(abs(diff), float3(0.2126, 0.7152, 0.0722));
|
||
// 如果差异小于阈值，则不进行锐化 (factor = 0)
|
||
// 使用 smoothstep 让过渡更平滑
|
||
float factor = smoothstep(threshold, threshold + 0.001, lumaDiff);
|
||
|
||
// 5. 应用锐化
|
||
half3 sharpened = center.rgb + diff * strength * factor;
|
||
|
||
// 6. 【优化二】钳制 (Clamp) - 防光晕用
|
||
// 限制锐化后的值与原始值的偏差不能超过 clampVal
|
||
sharpened = max(sharpened, center.rgb - clampVal); // 不能太暗
|
||
sharpened = min(sharpened, center.rgb + clampVal); // 不能太亮
|
||
|
||
return half4(sharpened, center.a);
|
||
}
|
||
ENDHLSL
|
||
|
||
Pass
|
||
{
|
||
Name "Sharpen Pass"
|
||
HLSLPROGRAM
|
||
#pragma vertex Vert
|
||
#pragma fragment SharpenPassFragment
|
||
ENDHLSL
|
||
}
|
||
}
|
||
} |