[692] | 1 | // Vertex program for fresnel reflections / refractions |
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| 2 | void main_vp( |
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| 3 | float4 pos : POSITION, |
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| 4 | float4 normal : NORMAL, |
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| 5 | float2 tex : TEXCOORD0, |
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| 6 | |
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| 7 | out float4 oPos : POSITION, |
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| 8 | out float fresnel : COLOR, |
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| 9 | out float3 noiseCoord : TEXCOORD0, |
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| 10 | out float4 projectionCoord : TEXCOORD1, |
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| 11 | |
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| 12 | uniform float4x4 worldViewProjMatrix, |
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| 13 | uniform float3 eyePosition, // object space |
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| 14 | uniform float fresnelBias, |
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| 15 | uniform float fresnelScale, |
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| 16 | uniform float fresnelPower, |
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| 17 | uniform float timeVal, |
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| 18 | uniform float scale, // the amount to scale the noise texture by |
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| 19 | uniform float scroll, // the amount by which to scroll the noise |
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| 20 | uniform float noise // the noise perturb as a factor of the time |
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| 21 | ) |
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| 22 | { |
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| 23 | oPos = mul(worldViewProjMatrix, pos); |
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| 24 | // Projective texture coordinates, adjust for mapping |
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| 25 | float4x4 scalemat = float4x4(0.5, 0, 0, 0.5, |
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| 26 | 0,-0.5, 0, 0.5, |
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| 27 | 0, 0, 0.5, 0.5, |
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| 28 | 0, 0, 0, 1); |
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| 29 | projectionCoord = mul(scalemat, oPos); |
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| 30 | // Noise map coords |
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| 31 | noiseCoord.xy = (tex + (timeVal * scroll)) * scale; |
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| 32 | noiseCoord.z = noise * timeVal; |
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| 33 | |
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| 34 | // calc fresnel factor (reflection coefficient) |
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| 35 | float3 eyeDir = normalize(pos.xyz - eyePosition); |
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| 36 | fresnel = fresnelBias + fresnelScale * pow(1 + dot(eyeDir, normal), fresnelPower); |
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| 37 | |
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| 38 | } |
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| 39 | |
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| 40 | // Fragment program for distorting a texture using a 3D noise texture |
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| 41 | void main_fp( |
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| 42 | float fresnel : COLOR, |
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| 43 | float3 noiseCoord : TEXCOORD0, |
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| 44 | float4 projectionCoord : TEXCOORD1, |
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| 45 | |
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| 46 | out float4 col : COLOR, |
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| 47 | |
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| 48 | uniform float distortionRange, |
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| 49 | uniform float4 tintColour, |
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| 50 | uniform sampler3D noiseMap, |
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| 51 | uniform sampler2D reflectMap, |
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| 52 | uniform sampler2D refractMap |
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| 53 | ) |
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| 54 | { |
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| 55 | // Randomly chosen offset for y noise sample |
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| 56 | float3 yoffset = float3(0.31, 0.58, 0.23); |
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| 57 | float2 distort; |
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| 58 | // Sample the noise texture at 2 places |
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| 59 | distort.x = tex3D(noiseMap, noiseCoord).x; |
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| 60 | distort.y = tex3D(noiseMap, noiseCoord + yoffset).x; |
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| 61 | // Scale the distortion from [0,1] to [-range,range] |
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| 62 | distort = (distort * 2 - 1) * distortionRange; |
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| 63 | |
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| 64 | // Do the tex projection manually so we can distort _after_ |
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| 65 | float2 final = projectionCoord.xy / projectionCoord.w; |
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| 66 | final += distort; |
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| 67 | |
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| 68 | float4 reflectionColour = tex2D(reflectMap, final); |
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| 69 | float4 refractionColour = tex2D(refractMap, final) + tintColour; |
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| 70 | col = lerp(refractionColour, reflectionColour, fresnel); |
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| 71 | |
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| 72 | |
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| 73 | } |
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