Rasagar/Library/PackageCache/com.unity.terrain-tools/Shaders/TwistHeight.shader
2024-08-26 23:07:20 +03:00

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Shader "Hidden/TerrainTools/TwistHeight" {
Properties { _MainTex ("Texture", any) = "" {} }
SubShader {
ZTest Always Cull Off ZWrite Off
CGINCLUDE
#include "UnityCG.cginc"
#include "Packages/com.unity.terrain-tools/Shaders/TerrainTools.hlsl"
sampler2D _MainTex;
float4 _MainTex_TexelSize; // 1/width, 1/height, width, height
sampler2D _BrushTex;
sampler2D _FilterTex;
float4 _BrushParams;
#define BRUSH_STRENGTH (_BrushParams[0])
#define BRUSH_TARGETHEIGHT (_BrushParams[1])
#define BRUSH_TWISTAMOUNT (_BrushParams[2])
#define BRUSH_ROTATION (_BrushParams[3])
struct appdata_t {
float4 vertex : POSITION;
float2 pcUV : TEXCOORD0;
};
struct v2f {
float4 vertex : SV_POSITION;
float2 pcUV : TEXCOORD0;
};
v2f vert(appdata_t v)
{
v2f o;
o.vertex = UnityObjectToClipPos(v.vertex);
o.pcUV = v.pcUV;
return o;
}
ENDCG
Pass // 11 Twist
{
Name "Twist Height"
CGPROGRAM
#pragma vertex vert
#pragma fragment TwistHeight
float3 RotateUVs(float2 sourceUV, float rotAngle)
{
float4 rotAxes;
rotAxes.x = cos(rotAngle);
rotAxes.y = sin(rotAngle);
rotAxes.w = rotAxes.x;
rotAxes.z = -rotAxes.y;
float2 tempUV = sourceUV - float2(0.5, 0.5);
float3 retVal;
// We fix some flaws by setting zero-value to out of range UVs, so what we do here
// is test if we're out of range and store the mask in the third component.
retVal.xy = float2(dot(rotAxes.xy, tempUV), dot(rotAxes.zw, tempUV)) + float2(0.5, 0.5);
tempUV = clamp(retVal.xy, float2(0.0, 0.0), float2(1.0, 1.0));
retVal.z = ((tempUV.x == retVal.x) && (tempUV.y == retVal.y)) ? 1.0 : 0.0;
return retVal;
}
float4 TwistHeight(v2f i) : SV_Target
{
float2 brushUV = PaintContextUVToBrushUV(i.pcUV);
float2 heightmapUV = i.pcUV;
// out of bounds multiplier
float oob = all(saturate(brushUV) == brushUV) ? 1.0f : 0.0f;
//rotate the unpack uvs as a function of distance from the center
//float centerDistance = distance(i.texcoord, float2(0.5, 0.5));
float twistAmt = BRUSH_TWISTAMOUNT;// *centerDistance; //todo: allow user to specify
float3 twistedUVs = RotateUVs(heightmapUV, twistAmt);
float height = UnpackHeightmap(tex2D(_MainTex, heightmapUV));
float brushStrength = oob * BRUSH_STRENGTH * UnpackHeightmap(tex2D(_BrushTex, brushUV)) * UnpackHeightmap(tex2D(_FilterTex, i.pcUV));
float h = UnpackHeightmap(tex2D(_MainTex, twistedUVs.xy));
return PackHeightmap(lerp(height, h, saturate(brushStrength)));
}
ENDCG
}
}
Fallback Off
}