[692] | 1 | // oceanGLSL.frag |
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| 2 | // fragment program for Ocean water simulation |
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| 3 | // 05 Aug 2005 |
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| 4 | // adapted for Ogre by nfz |
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| 5 | // converted from HLSL to GLSL |
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| 6 | // original shader source from Render Monkey 1.6 Reflections Refractions.rfx |
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| 7 | |
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| 8 | // 06 Aug 2005: moved uvw calculation from fragment program into vertex program |
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| 9 | |
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| 10 | uniform float fadeBias; |
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| 11 | uniform float fadeExp; |
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| 12 | uniform vec4 waterColor; |
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| 13 | uniform sampler3D Noise; |
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| 14 | uniform samplerCube skyBox; |
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| 15 | |
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| 16 | varying vec3 uvw; |
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| 17 | varying vec3 normal; |
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| 18 | varying vec3 vVec; |
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| 19 | |
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| 20 | void main(void) |
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| 21 | { |
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| 22 | // in OpenGL Ogre uses Devil 1.6.7 for loading dds textures. |
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| 23 | // But Devil buggers up the green and blue channels of the 3D |
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| 24 | // texture by setting them to zero so only the red channel has good data |
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| 25 | // Dx9 loads the texture properly but if we want things to look the same |
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| 26 | // between Dx9 and GL we only use the red channel for now until Devil dds issues are fixed |
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| 27 | vec3 noisy = texture3D(Noise, uvw).xxx; |
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| 28 | |
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| 29 | // convert to signed noise |
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| 30 | vec3 bump = 2.0 * noisy - 1.0; |
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| 31 | bump.xz *= 0.15; |
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| 32 | // Make sure the normal always points upwards |
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| 33 | // note that Ogres y axis is vertical (RM Z axis is vertical) |
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| 34 | bump.y = 0.8 * abs(bump.y) + 0.2; |
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| 35 | // Offset the surface normal with the bump |
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| 36 | bump = normalize(normal + bump); |
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| 37 | |
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| 38 | // Find the reflection vector |
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| 39 | vec3 normView = normalize(vVec); |
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| 40 | vec3 reflVec = reflect(normView, bump); |
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| 41 | // Ogre has z flipped for cubemaps |
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| 42 | reflVec.z = -reflVec.z; |
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| 43 | vec4 refl = textureCube(skyBox, reflVec); |
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| 44 | |
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| 45 | // set up for fresnel calc |
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| 46 | float lrp = 1.0 - dot(-normView, bump); |
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| 47 | |
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| 48 | // Interpolate between the water color and reflection for fresnel effect |
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| 49 | gl_FragColor = mix(waterColor, refl, clamp(fadeBias + pow(lrp, fadeExp), 0.0, 1.0) ); |
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| 50 | } |
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