Hello everyone,
My goal is to make a text, that changes color depending on what is behind it (eg. photoshop blending mode “difference”). I found a shader on a forum, that achieves exactly that.
However since text object uses its own shader I need to somehow combine these two, which I am quite struggling to do so.
I am using a TextMeshPro/Distance Field shader for the text object:
Shader "TextMeshPro/Distance Field" {
Properties {
_FaceTex ("Face Texture", 2D) = "white" {}
_FaceUVSpeedX ("Face UV Speed X", Range(-5, 5)) = 0.0
_FaceUVSpeedY ("Face UV Speed Y", Range(-5, 5)) = 0.0
_FaceColor ("Face Color", Color) = (1,1,1,1)
_FaceDilate ("Face Dilate", Range(-1,1)) = 0
_OutlineColor ("Outline Color", Color) = (0,0,0,1)
_OutlineTex ("Outline Texture", 2D) = "white" {}
_OutlineUVSpeedX ("Outline UV Speed X", Range(-5, 5)) = 0.0
_OutlineUVSpeedY ("Outline UV Speed Y", Range(-5, 5)) = 0.0
_OutlineWidth ("Outline Thickness", Range(0, 1)) = 0
_OutlineSoftness ("Outline Softness", Range(0,1)) = 0
_Bevel ("Bevel", Range(0,1)) = 0.5
_BevelOffset ("Bevel Offset", Range(-0.5,0.5)) = 0
_BevelWidth ("Bevel Width", Range(-.5,0.5)) = 0
_BevelClamp ("Bevel Clamp", Range(0,1)) = 0
_BevelRoundness ("Bevel Roundness", Range(0,1)) = 0
_LightAngle ("Light Angle", Range(0.0, 6.2831853)) = 3.1416
_SpecularColor ("Specular", Color) = (1,1,1,1)
_SpecularPower ("Specular", Range(0,4)) = 2.0
_Reflectivity ("Reflectivity", Range(5.0,15.0)) = 10
_Diffuse ("Diffuse", Range(0,1)) = 0.5
_Ambient ("Ambient", Range(1,0)) = 0.5
_BumpMap ("Normal map", 2D) = "bump" {}
_BumpOutline ("Bump Outline", Range(0,1)) = 0
_BumpFace ("Bump Face", Range(0,1)) = 0
_ReflectFaceColor ("Reflection Color", Color) = (0,0,0,1)
_ReflectOutlineColor("Reflection Color", Color) = (0,0,0,1)
_Cube ("Reflection Cubemap", Cube) = "black" { /* TexGen CubeReflect */ }
_EnvMatrixRotation ("Texture Rotation", vector) = (0, 0, 0, 0)
_UnderlayColor ("Border Color", Color) = (0,0,0, 0.5)
_UnderlayOffsetX ("Border OffsetX", Range(-1,1)) = 0
_UnderlayOffsetY ("Border OffsetY", Range(-1,1)) = 0
_UnderlayDilate ("Border Dilate", Range(-1,1)) = 0
_UnderlaySoftness ("Border Softness", Range(0,1)) = 0
_GlowColor ("Color", Color) = (0, 1, 0, 0.5)
_GlowOffset ("Offset", Range(-1,1)) = 0
_GlowInner ("Inner", Range(0,1)) = 0.05
_GlowOuter ("Outer", Range(0,1)) = 0.05
_GlowPower ("Falloff", Range(1, 0)) = 0.75
_WeightNormal ("Weight Normal", float) = 0
_WeightBold ("Weight Bold", float) = 0.5
_ShaderFlags ("Flags", float) = 0
_ScaleRatioA ("Scale RatioA", float) = 1
_ScaleRatioB ("Scale RatioB", float) = 1
_ScaleRatioC ("Scale RatioC", float) = 1
_MainTex ("Font Atlas", 2D) = "white" {}
_TextureWidth ("Texture Width", float) = 512
_TextureHeight ("Texture Height", float) = 512
_GradientScale ("Gradient Scale", float) = 5.0
_ScaleX ("Scale X", float) = 1.0
_ScaleY ("Scale Y", float) = 1.0
_PerspectiveFilter ("Perspective Correction", Range(0, 1)) = 0.875
_Sharpness ("Sharpness", Range(-1,1)) = 0
_VertexOffsetX ("Vertex OffsetX", float) = 0
_VertexOffsetY ("Vertex OffsetY", float) = 0
_MaskCoord ("Mask Coordinates", vector) = (0, 0, 32767, 32767)
_ClipRect ("Clip Rect", vector) = (-32767, -32767, 32767, 32767)
_MaskSoftnessX ("Mask SoftnessX", float) = 0
_MaskSoftnessY ("Mask SoftnessY", float) = 0
_StencilComp ("Stencil Comparison", Float) = 8
_Stencil ("Stencil ID", Float) = 0
_StencilOp ("Stencil Operation", Float) = 0
_StencilWriteMask ("Stencil Write Mask", Float) = 255
_StencilReadMask ("Stencil Read Mask", Float) = 255
_ColorMask ("Color Mask", Float) = 15
}
SubShader {
Tags
{
"Queue"="Transparent"
"IgnoreProjector"="True"
"RenderType"="Transparent"
}
Stencil
{
Ref [_Stencil]
Comp [_StencilComp]
Pass [_StencilOp]
ReadMask [_StencilReadMask]
WriteMask [_StencilWriteMask]
}
Cull [_CullMode]
ZWrite Off
Lighting Off
Fog { Mode Off }
ZTest [unity_GUIZTestMode]
Blend One OneMinusSrcAlpha
ColorMask [_ColorMask]
Pass {
CGPROGRAM
#pragma target 3.0
#pragma vertex VertShader
#pragma fragment PixShader
#pragma shader_feature __ BEVEL_ON
#pragma shader_feature __ UNDERLAY_ON UNDERLAY_INNER
#pragma shader_feature __ GLOW_ON
#pragma multi_compile __ UNITY_UI_CLIP_RECT
#pragma multi_compile __ UNITY_UI_ALPHACLIP
#include "UnityCG.cginc"
#include "UnityUI.cginc"
#include "TMPro_Properties.cginc"
#include "TMPro.cginc"
struct vertex_t {
UNITY_VERTEX_INPUT_INSTANCE_ID
float4 position : POSITION;
float3 normal : NORMAL;
fixed4 color : COLOR;
float2 texcoord0 : TEXCOORD0;
float2 texcoord1 : TEXCOORD1;
};
struct pixel_t {
UNITY_VERTEX_INPUT_INSTANCE_ID
UNITY_VERTEX_OUTPUT_STEREO
float4 position : SV_POSITION;
fixed4 color : COLOR;
float2 atlas : TEXCOORD0; // Atlas
float4 param : TEXCOORD1; // alphaClip, scale, bias, weight
float4 mask : TEXCOORD2; // Position in object space(xy), pixel Size(zw)
float3 viewDir : TEXCOORD3;
#if (UNDERLAY_ON || UNDERLAY_INNER)
float4 texcoord2 : TEXCOORD4; // u,v, scale, bias
fixed4 underlayColor : COLOR1;
#endif
float4 textures : TEXCOORD5;
};
// Used by Unity internally to handle Texture Tiling and Offset.
float4 _FaceTex_ST;
float4 _OutlineTex_ST;
pixel_t VertShader(vertex_t input)
{
pixel_t output;
UNITY_INITIALIZE_OUTPUT(pixel_t, output);
UNITY_SETUP_INSTANCE_ID(input);
UNITY_TRANSFER_INSTANCE_ID(input,output);
UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(output);
float bold = step(input.texcoord1.y, 0);
float4 vert = input.position;
vert.x += _VertexOffsetX;
vert.y += _VertexOffsetY;
float4 vPosition = UnityObjectToClipPos(vert);
float2 pixelSize = vPosition.w;
pixelSize /= float2(_ScaleX, _ScaleY) * abs(mul((float2x2)UNITY_MATRIX_P, _ScreenParams.xy));
float scale = rsqrt(dot(pixelSize, pixelSize));
scale *= abs(input.texcoord1.y) * _GradientScale * (_Sharpness + 1);
if (UNITY_MATRIX_P[3][3] == 0) scale = lerp(abs(scale) * (1 - _PerspectiveFilter), scale, abs(dot(UnityObjectToWorldNormal(input.normal.xyz), normalize(WorldSpaceViewDir(vert)))));
float weight = lerp(_WeightNormal, _WeightBold, bold) / 4.0;
weight = (weight + _FaceDilate) * _ScaleRatioA * 0.5;
float bias =(.5 - weight) + (.5 / scale);
float alphaClip = (1.0 - _OutlineWidth * _ScaleRatioA - _OutlineSoftness * _ScaleRatioA);
#if GLOW_ON
alphaClip = min(alphaClip, 1.0 - _GlowOffset * _ScaleRatioB - _GlowOuter * _ScaleRatioB);
#endif
alphaClip = alphaClip / 2.0 - ( .5 / scale) - weight;
#if (UNDERLAY_ON || UNDERLAY_INNER)
float4 underlayColor = _UnderlayColor;
underlayColor.rgb *= underlayColor.a;
float bScale = scale;
bScale /= 1 + ((_UnderlaySoftness*_ScaleRatioC) * bScale);
float bBias = (0.5 - weight) * bScale - 0.5 - ((_UnderlayDilate * _ScaleRatioC) * 0.5 * bScale);
float x = -(_UnderlayOffsetX * _ScaleRatioC) * _GradientScale / _TextureWidth;
float y = -(_UnderlayOffsetY * _ScaleRatioC) * _GradientScale / _TextureHeight;
float2 bOffset = float2(x, y);
#endif
// Generate UV for the Masking Texture
float4 clampedRect = clamp(_ClipRect, -2e10, 2e10);
float2 maskUV = (vert.xy - clampedRect.xy) / (clampedRect.zw - clampedRect.xy);
// Support for texture tiling and offset
float2 textureUV = UnpackUV(input.texcoord1.x);
float2 faceUV = TRANSFORM_TEX(textureUV, _FaceTex);
float2 outlineUV = TRANSFORM_TEX(textureUV, _OutlineTex);
output.position = vPosition;
output.color = input.color;
output.atlas = input.texcoord0;
output.param = float4(alphaClip, scale, bias, weight);
output.mask = half4(vert.xy * 2 - clampedRect.xy - clampedRect.zw, 0.25 / (0.25 * half2(_MaskSoftnessX, _MaskSoftnessY) + pixelSize.xy));
output.viewDir = mul((float3x3)_EnvMatrix, _WorldSpaceCameraPos.xyz - mul(unity_ObjectToWorld, vert).xyz);
#if (UNDERLAY_ON || UNDERLAY_INNER)
output.texcoord2 = float4(input.texcoord0 + bOffset, bScale, bBias);
output.underlayColor = underlayColor;
#endif
output.textures = float4(faceUV, outlineUV);
return output;
}
fixed4 PixShader(pixel_t input) : SV_Target
{
UNITY_SETUP_INSTANCE_ID(input);
float c = tex2D(_MainTex, input.atlas).a;
#ifndef UNDERLAY_ON
clip(c - input.param.x);
#endif
float scale = input.param.y;
float bias = input.param.z;
float weight = input.param.w;
float sd = (bias - c) * scale;
float outline = (_OutlineWidth * _ScaleRatioA) * scale;
float softness = (_OutlineSoftness * _ScaleRatioA) * scale;
half4 faceColor = _FaceColor;
half4 outlineColor = _OutlineColor;
faceColor.rgb *= input.color.rgb;
faceColor *= tex2D(_FaceTex, input.textures.xy + float2(_FaceUVSpeedX, _FaceUVSpeedY) * _Time.y);
outlineColor *= tex2D(_OutlineTex, input.textures.zw + float2(_OutlineUVSpeedX, _OutlineUVSpeedY) * _Time.y);
faceColor = GetColor(sd, faceColor, outlineColor, outline, softness);
#if BEVEL_ON
float3 dxy = float3(0.5 / _TextureWidth, 0.5 / _TextureHeight, 0);
float3 n = GetSurfaceNormal(input.atlas, weight, dxy);
float3 bump = UnpackNormal(tex2D(_BumpMap, input.textures.xy + float2(_FaceUVSpeedX, _FaceUVSpeedY) * _Time.y)).xyz;
bump *= lerp(_BumpFace, _BumpOutline, saturate(sd + outline * 0.5));
n = normalize(n- bump);
float3 light = normalize(float3(sin(_LightAngle), cos(_LightAngle), -1.0));
float3 col = GetSpecular(n, light);
faceColor.rgb += col*faceColor.a;
faceColor.rgb *= 1-(dot(n, light)*_Diffuse);
faceColor.rgb *= lerp(_Ambient, 1, n.z*n.z);
fixed4 reflcol = texCUBE(_Cube, reflect(input.viewDir, -n));
faceColor.rgb += reflcol.rgb * lerp(_ReflectFaceColor.rgb, _ReflectOutlineColor.rgb, saturate(sd + outline * 0.5)) * faceColor.a;
#endif
#if UNDERLAY_ON
float d = tex2D(_MainTex, input.texcoord2.xy).a * input.texcoord2.z;
faceColor += input.underlayColor * saturate(d - input.texcoord2.w) * (1 - faceColor.a);
#endif
#if UNDERLAY_INNER
float d = tex2D(_MainTex, input.texcoord2.xy).a * input.texcoord2.z;
faceColor += input.underlayColor * (1 - saturate(d - input.texcoord2.w)) * saturate(1 - sd) * (1 - faceColor.a);
#endif
#if GLOW_ON
float4 glowColor = GetGlowColor(sd, scale);
faceColor.rgb += glowColor.rgb * glowColor.a;
#endif
// Alternative implementation to UnityGet2DClipping with support for softness.
#if UNITY_UI_CLIP_RECT
half2 m = saturate((_ClipRect.zw - _ClipRect.xy - abs(input.mask.xy)) * input.mask.zw);
faceColor *= m.x * m.y;
#endif
#if UNITY_UI_ALPHACLIP
clip(faceColor.a - 0.001);
#endif
return faceColor * input.color.a;
}
ENDCG
}
}
Fallback "TextMeshPro/Mobile/Distance Field"
CustomEditor "TMPro.EditorUtilities.TMP_SDFShaderGUI"
}
and this is the “difference” shader:
//ddInvertMapped shader: Daniel DeEntremont
//Apply this shader to a mesh and watch all pixels behind the mesh become inverted!
//Now has a texture mask input. White will invert colors behind while black remains the same.
Shader "ddShaders/ddInvertMapped" {
Properties
{
_Color ("Tint Color", Color) = (1,1,1,1)
_MainTex("Main Texture", 2D) = "white"{}
}
SubShader
{
Tags { "Queue"="Transparent" }
Pass
{
ZWrite On
ColorMask 0
}
Pass
{
Blend OneMinusDstColor OneMinusSrcColor //invert blending, so long as FG color is 1,1,1,1
BlendOp Add
SetTexture [_MainTex]
{
constantColor [_Color]
combine texture * constant
}
}
}//end subshader
}//end shader
I have tried to put the subshader from the “difference” code at the end of the text shader. Then I also tried to just add it as additional passes instead, but none of it seems to be that straight forward.
Thank you for any possible thoughts on this!