windows-nt/Source/XPSP1/NT/multimedia/directx/dxg/ref8/rast/rastattr.cpp
2020-09-26 16:20:57 +08:00

248 lines
8.1 KiB
C++

///////////////////////////////////////////////////////////////////////////////
// Copyright (C) Microsoft Corporation, 2000.
//
// rastattr.cpp
//
// Direct3D Reference Device -
//
///////////////////////////////////////////////////////////////////////////////
#include "pch.cpp"
#pragma hdrstop
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
void RDAttribute::Init(
RefRast* pRefRast, // RefRast with which this attrib is used
UINT cDimensionality,
BOOL bPerspective,
BOOL bClamp )
{
m_pRR = pRefRast;
m_cDimensionality = cDimensionality;
m_bPerspective = bPerspective;
m_bClamp = bClamp;
m_cProjection = 0;
m_dwWrapFlags = 0x0;
m_bFlatShade = FALSE;
}
///////////////////////////////////////////////////////////////////////////////
//
// Sampling Routines
//
///////////////////////////////////////////////////////////////////////////////
//-----------------------------------------------------------------------------
//
// Sample - Sample attribute at given location.
//
//-----------------------------------------------------------------------------
void RDAttribute::Sample(
FLOAT* pSample,
FLOAT fX,
FLOAT fY,
BOOL bNoProjectionOverride, // disables projection if TRUE
BOOL bClampOverride) // enables (forces) clamp if TRUE
{
FLOAT fPScale = 1.0F;
if (m_cProjection && !m_bFlatShade && !bNoProjectionOverride)
{
// note that perspective is already incorporated into projective coord
fPScale = 1.0F/( fX*m_fA[m_cProjection] + fY*m_fB[m_cProjection] + m_fC[m_cProjection] );
}
else if (m_bPerspective && !m_bFlatShade)
{
fPScale = m_pRR->m_fW[m_pRR->m_iPix];
}
for ( UINT i=0; i<m_cDimensionality; i++)
{
if (m_bFlatShade)
{
*(pSample+i) = m_fC[i];
}
else
{
*(pSample+i) =
fPScale * ( fX*m_fA[i] + fY*m_fB[i] + m_fC[i] );
}
if (m_bClamp || bClampOverride)
{
*(pSample+i) = MIN( 1.F, MAX( 0.F, *(pSample+i) ) );
}
}
}
//-----------------------------------------------------------------------------
//
// Sample - Sample scalar attribute at given location. Assumes no perspective
// or projection. (Used for W or Depth.)
//
//-----------------------------------------------------------------------------
FLOAT RDAttribute::Sample(
FLOAT fX,
FLOAT fY)
{
return fX*m_fA[0] + fY*m_fB[0] + m_fC[0];
}
///////////////////////////////////////////////////////////////////////////////
//
// Setup Routines
//
///////////////////////////////////////////////////////////////////////////////
//-----------------------------------------------------------------------------
//
// WrapDiff - returns the difference (B-A) as defined under the D3D WRAPU/V
// rules which is the shortest path between the two assuming a coincident
// position at 1. and 0. The fA and fB input range is 0. to 1.
//
//-----------------------------------------------------------------------------
static FLOAT
WrapDiff( FLOAT fB, FLOAT fA )
{
// compute straight distance
FLOAT fDist1 = fB - fA;
// compute distance 'warping' between 0. and 1.
FLOAT fDist2 = ( fDist1 < 0 ) ? ( fDist1+1 ) : ( fDist1-1 );
// return minimum of these
return ( fabs( fDist1) < fabs( fDist2) ) ? ( fDist1) : ( fDist2 );
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
void RDAttribute::Setup(
const FLOAT* pVtx0, const FLOAT* pVtx1, const FLOAT* pVtx2)
{
if (m_pRR->m_bIsLine)
{
LineSetup( pVtx0, pVtx1, pVtx2 );
return;
}
for ( UINT i=0; i<m_cDimensionality; i++)
{
FLOAT fVal0 = (pVtx0) ? (*(pVtx0+i)) : (0.);
FLOAT fVal1 = (pVtx1) ? (*(pVtx1+i)) : (0.);
FLOAT fVal2 = (pVtx2) ? (*(pVtx2+i)) : (0.);
if (m_bFlatShade)
{
m_fA[i] = m_fB[i] = 0.F;
switch ( m_pRR->m_iFlatVtx )
{
default:
case 0: m_fC[i] = fVal0; break;
case 1: m_fC[i] = fVal1; break;
case 2: m_fC[i] = fVal2; break;
}
continue;
}
// extract wrap flag for this dimension
BOOL bWrap = m_dwWrapFlags & (1<<i);
// compute adjusted values for vertices 1,2 based on wrap flag
FLOAT fVal1P = bWrap ? ( fVal0 + WrapDiff(fVal1,fVal0) ) : (fVal1);
FLOAT fVal2P = bWrap ? ( fVal0 + WrapDiff(fVal2,fVal0) ) : (fVal2);
// compute (maybe) perspective corrected linear deltas along two edges
FLOAT fRHW0 = (m_bPerspective) ? (m_pRR->m_fRHW0) : (1.0F);
FLOAT fRHW1 = (m_bPerspective) ? (m_pRR->m_fRHW1) : (1.0F);
FLOAT fRHW2 = (m_bPerspective) ? (m_pRR->m_fRHW2) : (1.0F);
FLOAT fDelAttrib10 = ( fVal1P * fRHW1 ) - ( fVal0 * fRHW0 );
FLOAT fDelAttrib20 = ( fVal2P * fRHW2 ) - ( fVal0 * fRHW0 );
// compute A & B terms (dVdX and dVdY)
m_fA[i] = m_pRR->m_fTriOODet *
( fDelAttrib10 * m_pRR->m_fDelY20 + fDelAttrib20 * m_pRR->m_fDelY01 );
m_fB[i] = m_pRR->m_fTriOODet *
( fDelAttrib20 * m_pRR->m_fDelX10 + fDelAttrib10 * m_pRR->m_fDelX02 );
// compute C term (Fv = A*Xv + B*Yv + C => C = Fv - A*Xv - B*Yv)
m_fC[i] = ( fVal0 * fRHW0 )
- ( m_fA[i] * m_pRR->m_fX0 ) - ( m_fB[i] * m_pRR->m_fY0 );
}
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
void RDAttribute::LineSetup(
const FLOAT* pVtx0, const FLOAT* pVtx1, const FLOAT* pVtxFlat)
{
for ( UINT i=0; i<m_cDimensionality; i++)
{
FLOAT fVal0 = (pVtx0) ? (*(pVtx0+i)) : (0.);
FLOAT fVal1 = (pVtx1) ? (*(pVtx1+i)) : (0.);
if (m_bFlatShade)
{
m_fA[i] = m_fB[i] = 0.F;
m_fC[i] = (pVtxFlat) ? (*(pVtxFlat+i)) : fVal0;
continue;
}
// extract wrap flag for this dimension
BOOL bWrap = m_dwWrapFlags & (1<<i);
// compute adjusted values for vertices 1,2 based on wrap flag
FLOAT fVal1P = bWrap ? ( fVal0 + WrapDiff(fVal1,fVal0) ) : (fVal1);
// compute (maybe) perspective corrected linear deltas along two edges
FLOAT fRHW0 = (m_bPerspective) ? (m_pRR->m_fRHW0) : (1.0F);
FLOAT fRHW1 = (m_bPerspective) ? (m_pRR->m_fRHW1) : (1.0F);
FLOAT fDelta = ( fVal1P*fRHW1 - fVal0*fRHW0) / m_pRR->m_fLineMajorLength;
m_fA[i] = ( m_pRR->m_bLineXMajor ) ? ( fDelta ) : ( 0. );
m_fB[i] = ( m_pRR->m_bLineXMajor ) ? ( 0. ) : ( fDelta );
// compute C term (Fv = A*Xv + B*Yv + C => C = Fv - A*Xv - B*Yv)
m_fC[i] = ( fVal0* fRHW0)
- ( m_fA[i] * m_pRR->m_fX0 ) - ( m_fB[i] * m_pRR->m_fY0 );
}
}
//-----------------------------------------------------------------------------
//
// Setup attribute given packed DWORD color. Color format is that of the
// colors in the FVF vertex, which corresponds to D3DFMT_A8R8G8B8 (and is
// the same as D3DCOLOR).
//
//-----------------------------------------------------------------------------
void RDAttribute::Setup(
DWORD dwVtx0, DWORD dwVtx1, DWORD dwVtx2)
{
FLOAT fVtx0[4];
FLOAT fVtx1[4];
FLOAT fVtx2[4];
fVtx0[0] = RGBA_GETRED( dwVtx0 ) * (1./255.);
fVtx0[1] = RGBA_GETGREEN( dwVtx0 ) * (1./255.);
fVtx0[2] = RGBA_GETBLUE( dwVtx0 ) * (1./255.);
fVtx0[3] = RGBA_GETALPHA( dwVtx0 ) * (1./255.);
fVtx1[0] = RGBA_GETRED( dwVtx1 ) * (1./255.);
fVtx1[1] = RGBA_GETGREEN( dwVtx1 ) * (1./255.);
fVtx1[2] = RGBA_GETBLUE( dwVtx1 ) * (1./255.);
fVtx1[3] = RGBA_GETALPHA( dwVtx1 ) * (1./255.);
fVtx2[0] = RGBA_GETRED( dwVtx2 ) * (1./255.);
fVtx2[1] = RGBA_GETGREEN( dwVtx2 ) * (1./255.);
fVtx2[2] = RGBA_GETBLUE( dwVtx2 ) * (1./255.);
fVtx2[3] = RGBA_GETALPHA( dwVtx2 ) * (1./255.);
Setup( fVtx0, fVtx1, fVtx2);
}
///////////////////////////////////////////////////////////////////////////////
// end