Var* GBufferConditionerGLSL::_unconditionInput( Var *conditionedInput, MultiLine *meta )
{
Var *retVar = new Var;
retVar->setType("float4");
retVar->setName("_gbUnconditionedInput");
LangElement *outputDecl = new DecOp( retVar );
switch(mNormalStorageType)
{
case CartesianXYZ:
meta->addStatement( new GenOp( " // g-buffer unconditioner: float4(normal.xyz, depth)\r\n" ) );
meta->addStatement( new GenOp( " @ = float4(@, @.a);\r\n", outputDecl,
_posnegDecode(new GenOp("@.xyz", conditionedInput)), conditionedInput ) );
break;
case CartesianXY:
meta->addStatement( new GenOp( " // g-buffer unconditioner: float4(normal.xy, depth Hi + z-sign, depth Lo)\r\n" ) );
meta->addStatement( new GenOp( " @ = float4(@, @.a);\r\n", outputDecl,
_posnegDecode(new GenOp("@.xyz", conditionedInput)), conditionedInput ) );
meta->addStatement( new GenOp( " @.z *= sqrt(1.0 - dot(@.xy, @.xy));\r\n", retVar, retVar, retVar ) );
break;
case Spherical:
meta->addStatement( new GenOp( " // g-buffer unconditioner: float4(normal.theta, normal.phi, depth Hi, depth Lo)\r\n" ) );
meta->addStatement( new GenOp( " float2 spGPUAngles = @;\r\n", _posnegDecode(new GenOp("@.xy", conditionedInput)) ) );
meta->addStatement( new GenOp( " float2 sincosTheta;\r\n" ) );
meta->addStatement( new GenOp( " sincos(spGPUAngles.x * 3.14159265358979323846f, sincosTheta.x, sincosTheta.y);\r\n" ) );
meta->addStatement( new GenOp( " float2 sincosPhi = float2(sqrt(1.0 - spGPUAngles.y * spGPUAngles.y), spGPUAngles.y);\r\n" ) );
meta->addStatement( new GenOp( " @ = float4(sincosTheta.y * sincosPhi.x, sincosTheta.x * sincosPhi.x, sincosPhi.y, @.a);\r\n", outputDecl, conditionedInput ) );
break;
case LambertAzimuthal:
// Note we're casting to half to use partial precision
// sqrt which is much faster on older Geforces while
// still being acceptable for normals.
//
meta->addStatement( new GenOp( " // g-buffer unconditioner: float4(normal.X, normal.Y, depth Hi, depth Lo)\r\n" ) );
meta->addStatement( new GenOp( " float2 _inpXY = @;\r\n", _posnegDecode(new GenOp("@.xy", conditionedInput)) ) );
meta->addStatement( new GenOp( " float _xySQ = dot(_inpXY, _inpXY);\r\n" ) );
meta->addStatement( new GenOp( " @ = float4( sqrt(half(1.0 - (_xySQ / 4.0))) * _inpXY, -1.0 + (_xySQ / 2.0), @.a).xzyw;\r\n", outputDecl, conditionedInput ) );
break;
}
// Recover depth from encoding
if(mNormalStorageType != CartesianXYZ)
{
const U64 maxValPerChannel = 1 << mBitsPerChannel;
meta->addStatement( new GenOp( " \r\n // Decode depth\r\n" ) );
meta->addStatement( new GenOp( avar( " @.w = dot( @.zw, float2(1.0, 1.0/%llu.0));\r\n", maxValPerChannel - 1 ),
retVar, conditionedInput ) );
}
AssertFatal( retVar != NULL, avar( "Cannot uncondition input from buffer format: %s", GFXStringTextureFormat[getBufferFormat()] ) );
return retVar;
}
Var* GBufferConditionerGLSL::_unconditionInput( Var *conditionedInput, MultiLine *meta )
{
Var *retVar = new Var;
retVar->setType("vec4");
retVar->setName("_gbUnconditionedInput");
LangElement *outputDecl = new DecOp( retVar );
switch(mNormalStorageType)
{
case CartesianXYZ:
meta->addStatement( new GenOp( " // g-buffer unconditioner: vec4(normal.xyz, depth)\r\n" ) );
meta->addStatement( new GenOp( " @ = vec4(@, @.a);\r\n", outputDecl,
_posnegDecode(new GenOp("@.xyz", conditionedInput)), conditionedInput ) );
break;
case CartesianXY:
meta->addStatement( new GenOp( " // g-buffer unconditioner: vec4(normal.xy, depth Hi + z-sign, depth Lo)\r\n" ) );
meta->addStatement( new GenOp( " @ = vec4(@, @.a);\r\n", outputDecl,
_posnegDecode(new GenOp("@.xyz", conditionedInput)), conditionedInput ) );
meta->addStatement( new GenOp( " @.z *= sqrt(1.0 - dot(@.xy, @.xy));\r\n", retVar, retVar, retVar ) );
break;
case Spherical:
meta->addStatement( new GenOp( " // g-buffer unconditioner: vec4(normal.theta, normal.phi, depth Hi, depth Lo)\r\n" ) );
meta->addStatement( new GenOp( " vec2 spGPUAngles = @;\r\n", _posnegDecode(new GenOp("@.xy", conditionedInput)) ) );
meta->addStatement( new GenOp( " vec2 sincosTheta;\r\n" ) );
meta->addStatement( new GenOp( " sincosTheta.x = sin(spGPUAngles.x * 3.14159265358979323846);\r\n" ) );
meta->addStatement( new GenOp( " sincosTheta.y = cos(spGPUAngles.x * 3.14159265358979323846);\r\n" ) );
meta->addStatement( new GenOp( " vec2 sincosPhi = vec2(sqrt(1.0 - spGPUAngles.y * spGPUAngles.y), spGPUAngles.y);\r\n" ) );
meta->addStatement( new GenOp( " @ = vec4(sincosTheta.y * sincosPhi.x, sincosTheta.x * sincosPhi.x, sincosPhi.y, @.a);\r\n", outputDecl, conditionedInput ) );
break;
}
// Recover depth from encoding
if(mNormalStorageType != CartesianXYZ)
{
const U64 maxValPerChannel = 1 << mBitsPerChannel;
meta->addStatement( new GenOp( " \r\n // Decode depth\r\n" ) );
meta->addStatement( new GenOp( avar( " @.w = dot( @.zw, vec2(1.0, 1.0/%llu.0));\r\n", maxValPerChannel - 1 ),
retVar, conditionedInput ) );
}
AssertFatal( retVar != NULL, avar( "Cannot uncondition input from buffer format: %s", GFXStringTextureFormat[getBufferFormat()] ) );
return retVar;
}
