Initial commit

Assets/Procedural Worlds/Gaia/Shaders/Unity/Terrain Tools/SmoothHeight.shader

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+    Shader "Hidden/Gaia/SmoothHeight" {
+
+    Properties { _MainTex ("Texture", any) = "" {} 
+				//1-pixel height transform texture representing an animation curve
+				_HeightTransformTex ("Height Transform Texture", any) = "" {}
+	}
+
+    SubShader {
+
+        ZTest Always Cull Off ZWrite Off
+
+        CGINCLUDE
+            #include "UnityCG.cginc"
+            #include "TerrainTool.cginc"
+
+            sampler2D _MainTex;
+			sampler2D _HeightTransformTex;
+            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])
+
+			float4 _SmoothWeights; // centered, min, max, unused
+
+			static int KernelWeightCount = 7;
+			static float KernelWeights[7] = { 0.95f, 0.85f, 0.7f, 0.4f, 0.2f, 0.15f, 0.05f };
+
+
+            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
+		{
+			Name "Smooth Horizontal"
+
+			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment SmoothHorizontal
+
+			float4 SmoothHorizontal(v2f i) : SV_Target
+			{
+				float2 brushUV = PaintContextUVToBrushUV(i.pcUV);
+				float2 heightmapUV = PaintContextUVToHeightmapUV(i.pcUV);
+
+				// out of bounds multiplier
+				float oob = all(saturate(brushUV) == brushUV) ? 1.0f : 0.0f;
+
+				float height = UnpackHeightmap(tex2D(_MainTex, heightmapUV));
+				float brushStrength = BRUSH_STRENGTH * oob * UnpackHeightmap(tex2D(_BrushTex, brushUV));// *UnpackHeightmap(tex2D(_FilterTex, i.pcUV));
+				
+
+				float divisor = 1.0f;
+				float offset = 0.0f;
+				float h = height;
+			
+				for (int i = 0; i < KernelWeightCount; i++) {
+					offset += _MainTex_TexelSize.x * _SmoothWeights.w;
+					divisor += 2.0f * KernelWeights[i];
+
+					float2 rightUV = heightmapUV + float2(offset, 0.0f);
+					float2 leftUV = heightmapUV - float2(offset, 0.0f);
+
+					h += KernelWeights[i] * UnpackHeightmap(tex2D(_MainTex, rightUV));
+					h += KernelWeights[i] * UnpackHeightmap(tex2D(_MainTex, leftUV));
+				}
+
+				h /= divisor;
+
+				float3 new_height = float3(h, min(h, height), max(h, height));
+				h = dot(new_height, _SmoothWeights.xyz);
+				float transformedStrength = tex2D(_HeightTransformTex, h);
+				return lerp(height, h, brushStrength);
+				//return PackHeightmap(lerp(height,new_height,transformedStrength));
+			}
+			ENDCG
+		}
+
+		Pass
+		{
+			Name "Smooth Vertical"
+
+			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment SmoothVertical
+
+			float4 SmoothVertical(v2f i) : SV_Target
+			{
+				float2 brushUV = PaintContextUVToBrushUV(i.pcUV);
+				float2 heightmapUV = PaintContextUVToHeightmapUV(i.pcUV);
+
+				// out of bounds multiplier
+				float oob = all(saturate(brushUV) == brushUV) ? 1.0f : 0.0f;
+
+				float height = UnpackHeightmap(tex2D(_MainTex, heightmapUV));
+				float brushStrength = BRUSH_STRENGTH * oob * UnpackHeightmap(tex2D(_BrushTex, brushUV));// *UnpackHeightmap(tex2D(_FilterTex, i.pcUV));
+				
+				float divisor = 1.0f;
+				float offset = 0.0f;
+				float h = height;
+
+				for (int i = 0; i < KernelWeightCount; i++) {
+					offset += _MainTex_TexelSize.x * _SmoothWeights.w;
+					divisor += 2.0f * KernelWeights[i];
+
+					float2 upUV = heightmapUV + float2(0.0f, offset);
+					float2 downUV = heightmapUV - float2(0.0f, offset);
+
+					h += KernelWeights[i] * UnpackHeightmap(tex2D(_MainTex, upUV));
+					h += KernelWeights[i] * UnpackHeightmap(tex2D(_MainTex, downUV));
+				}
+
+				h /= divisor;
+
+				float3 new_height = float3(h, min(h, height), max(h, height));
+				h = dot(new_height, _SmoothWeights.xyz);
+				float transformedStrength = tex2D(_HeightTransformTex, h);
+				return lerp(height, h, brushStrength);
+				//return PackHeightmap(lerp(height,new_height,transformedStrength));
+			}
+			ENDCG
+		}
+
+		/*
+		Pass    // 3 smooth terrain
+		{
+			Name "Smooth Heights"
+
+			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment SmoothHeight
+
+			float4 _SmoothWeights;      // centered, min, max, unused
+
+			float aggregateHeight(float2 uv, out float oobWeight)
+			{
+				oobWeight = all(saturate(uv) == uv) ? 1.0f : 0.0f;
+				return oobWeight * UnpackHeightmap(tex2D(_MainTex, uv));
+			}
+
+			float4 SmoothHeight(v2f i) : SV_Target
+			{
+				float2 brushUV = PaintContextUVToBrushUV(i.pcUV);
+				float2 heightmapUV = PaintContextUVToHeightmapUV(i.pcUV);
+
+				// out of bounds multiplier
+				float oob = all(saturate(brushUV) == brushUV) ? 1.0f : 0.0f;
+
+				float height = UnpackHeightmap(tex2D(_MainTex, heightmapUV));
+				float brushStrength = BRUSH_STRENGTH * oob * UnpackHeightmap(tex2D(_BrushTex, brushUV)) * UnpackHeightmap(tex2D(_FilterTex, i.pcUV));
+
+				float h = 0.0F;
+				float xoffset = _MainTex_TexelSize.x * _SmoothWeights.w;
+				float yoffset = _MainTex_TexelSize.y * _SmoothWeights.w;
+
+				// 3*3 filter
+				h += height;
+
+				float sum = 1.0f;
+				float weight = 1.0f;
+				h += aggregateHeight(heightmapUV + float2( xoffset, 0), weight);
+				sum += weight;
+				h += aggregateHeight(heightmapUV + float2(-xoffset, 0), weight);
+				sum += weight;
+				h += aggregateHeight(heightmapUV + float2( xoffset, yoffset), weight) * 0.75f;
+				sum += 0.75f * weight;
+				h += aggregateHeight(heightmapUV + float2(-xoffset, yoffset), weight) * 0.75f;
+				sum += 0.75f * weight;
+				h += aggregateHeight(heightmapUV + float2( xoffset, -yoffset), weight) * 0.75f;
+				sum += 0.75f * weight;
+				h += aggregateHeight(heightmapUV + float2(-xoffset, -yoffset), weight) * 0.75f;
+				sum += 0.75f * weight;
+				h += aggregateHeight(heightmapUV + float2( 0, yoffset), weight);
+				sum += weight;
+				h += aggregateHeight(heightmapUV + float2( 0, -yoffset), weight);
+				sum += weight;
+				
+				h /= sum;
+				
+
+				float3 new_height = float3(h, min(h, height), max(h, height));
+				h = dot(new_height, _SmoothWeights.xyz);
+				return PackHeightmap(lerp(height, h, brushStrength));
+			}
+			ENDCG
+		}
+		*/
+    }
+    Fallback Off
+}