JurassicParkTrespasser/jp2_pc/Source/Lib/Renderer/Primitives/AMDK6/DrawSubTriangleWater.inl

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2018-01-01 22:07:24 +00:00
/***********************************************************************************************
*
* Copyright <20> DreamWorks Interactive, 1997.
*
* Contents:
* Specialized (non-template) versions of the DrawSubtriangle function for terrain.
* Optimized for the AMD K6-3D processor.
*
***********************************************************************************************
*
* $Log:: /JP2_PC/Source/Lib/Renderer/Primitives/AMDK6/DrawSubTriangleWater.cpp $
*
* 5 10/01/98 12:42a Asouth
* Added #ifdefs for MW build; explicit scope of fixed
*
* 4 98.04.30 5:22p Mmouni
* Added stippled texture primitives.
*
* 3 97.11.20 4:23p Mmouni
* Perspective routine now uses prologue/epilogue macros.
*
* 2 97.11.12 1:28p Mmouni
* Aligned inner loops for optimal pre-decode.
*
* 1 97.11.11 9:50p Mmouni
* Optimized for K6-3D.
*
* 1 97/11/09 7:07p Pkeet
* Initial implementation.
*
**********************************************************************************************/
#include "Common.hpp"
#include "Lib/View/Raster.hpp"
#include "Lib/Renderer/Primitives/DrawTriangle.hpp"
// Put this stuff in a seperate section for alignment.
#pragma code_seg("StriWater")
//
// Globals.
//
// Values supplied by the light blend module.
extern uint16 u2WaterMask;
extern uint16* pu2WaterAlpha;
// Zero extended version of u2WaterMask.
static uint32 u4WaterMask;
//
// Function implementations.
//
//*****************************************************************************************
//
// Perspective, alpha texture.
//
void DrawSubtriangle(TWaterPersp* pscan, CDrawPolygon<TWaterPersp>* pdtri)
{
static void* pvLastTexture = 0;
static void* pvLastFogClut = 0;
TWaterPersp* plinc = &pdtri->pedgeBase->lineIncrement;
Assert(pu2WaterAlpha);
__asm
{
// Get ready to do MMX/3DX.
femms
//
// Local copies of edge stepping values.
//
// fx_inc = pdtri->pedgeBase->lineIncrement.fxX;
// fx_diff = pdtri->pedgeBase->lineIncrement.fxXDifference;
// f_inc_uinvz = pdtri->pedgeBase->lineIncrement.indCoord.fUInvZ;
// f_inc_vinvz = pdtri->pedgeBase->lineIncrement.indCoord.fVInvZ;
// f_inc_invz = pdtri->pedgeBase->lineIncrement.indCoord.fInvZ;
//
mov eax,[plinc]
mov esi,[pdtri] // Pointer to polygon object.
mov ecx,[pscan] // Pointer to scanline object.
mov ebx,[eax]TWaterPersp.fxX
mov edx,[eax]TWaterPersp.fxXDifference
mov fx_inc,ebx
movq mm0,[eax]TWaterPersp.indCoord.fUInvZ
mov fx_diff,edx
mov ebx,[eax]TWaterPersp.indCoord.fInvZ
movq [tvEdgeStep.UInvZ],mm0
mov [tvEdgeStep.InvZ],ebx
//
// Setup:
// QWORD qMFactor = width,1,width,1
// Load global texture values.
//
movd mm3,[iTexWidth] // 0,0,0,Width
movd mm4,[u4OneOne] // 0,0,1,1
punpcklwd mm3,mm3 // 0,0,Width,Width
punpcklwd mm4,mm3 // Width,1,Width,1
movq mm0,[ecx]TWaterPersp.indCoord.fUInvZ // mm0 = (V/Z,U/Z)
movq [qMFactor],mm4 // Save mfactor
movd mm1,[ecx]TWaterPersp.indCoord.fInvZ // mm1 = (?,1/Z)
//
// Iterate through the scanlines that intersect the subtriangle.
//
// esi,ecx,mm0,mm1 setup.
//
Y_LOOP:
mov eax,[esi]CDrawPolygonBase.iY
mov ebx,[bEvenScanlinesOnly]
push ebp
// Check to see if we sould skip this scanline.
and eax,ebx
jnz END_OF_SCANLINE
//
// Setup for prespective correction and looping.
//
#ifdef __MWERKS__
#define SLTYPE TWaterPersp
#include "pspclamp3.inl"
#else
PERSPECTIVE_SCANLINE_PROLOGUE_CLAMP_3DX(TWaterPersp)
#endif
SUBDIVISION_LOOP:
//---------------------------------------------------------------------------
// Draw the subdivision.
//
// mm6,mm7 = texture values.
//
// Setup registers:
//
// eax = texel_index2 ebx = texel_index2
// ecx = clut pointer edx = dest_base_ptr
// esi = texture_base_ptr edi = pixel_offset & count
// ebp = alpha index mask
//
// mm0 = temp mm1 = temp
// mm2 = mfactor mm3 = uvmask
// mm6 = uvslope mm7 = uv (stepped once)
//
movq mm0,mm7 // Copy U1,V1
paddd mm7,mm6 // Step U,V
psrad mm0,16 // Shift for integer U1,V1
movq mm1,mm7 // Copy U2,V2
movq mm2,[qMFactor] // Load texture multipliers
psrad mm1,16 // Shift for integer U2,V2
mov ecx,[pu2WaterAlpha] // Water alpha table.
packssdw mm0,mm1 // Pack integer texture values
movzx ebp,[u2WaterMask] // Load water alpha mask.
dec esi // Hack to force SIB + offset in loop
dec ecx // Hack to force SIB + offset in loop
mov [pvBaseOfLine],edx // Save base of scanline pointer.
pmaddwd mm0,mm2 // Compute texture indicies.
mov [u4WaterMask],ebp // Save zero extended version of u2WaterMask.
movq [qIndexTemp],mm0 // Save texture indicies.
//
// Make sure we have more than 2 pixels left.
//
add edi,2
jl short INNER_LOOP_2P
jmp FINISH_REMAINDER
// Align start of loop to 1 past the beginning of a cache line.
ALIGN 16
nop
//
// Do two pixels at a time.
//
// mm0 = packed & masked U1,V1,U2,V2
// mm7 is stepped once.
//
INNER_LOOP_2P:
movzx eax,word ptr[edx + edi*2 - 4] // Get screen pixel 1.
paddd mm7,mm6 // Step U,V
movzx ebx,word ptr[edx + edi*2 - 2] // Get screen pixel 2.
movq mm0,mm7 // Copy U1,V1
psrad mm0,16 // Shift for integer U1,V1
paddd mm7,mm6 // Step U,V
and eax,ebp // And p1 with u2WaterMask.
mov edx,dword ptr[qIndexTemp] // Get texture index 1.
and ebx,ebp // And p2 with u2WaterMask.
mov ebp,dword ptr[qIndexTemp+4] // Get texture index 2.
movzx edx,word ptr[esi + edx*2 + 1] // Lookup texel 1.
movq mm1,mm7 // Copy U2,V2
movzx ebp,word ptr[esi + ebp*2 + 1] // Lookup texel 2.
psrad mm1,16 // Shift for integer U2,V2
packssdw mm0,mm1 // Pack integer texture values.
or eax,edx // Combine alhpa and screen pixel.
mov edx,[pvBaseOfLine] // Reload base of line pointer.
or ebx,ebp // Combine alhpa and screen pixel.
mov ebp,[u4WaterMask] // Re-load water alpha mask value.
movzx eax,word ptr[ecx + eax*2 + 1] // Lookup through alpha water table.
pmaddwd mm0,mm2 // Compute texture indicies.
movzx ebx,word ptr[ecx + ebx*2 + 1] // Lookup through alpha water table.
movq [qIndexTemp],mm0 // Save texture indicies.
mov [edx + edi*2 - 4],ax // Store pixel 1
mov [edx + edi*2 - 2],bx // Store pixel 2
add edi,2 // Inrcement index by 2
jl short INNER_LOOP_2P // Loop (while >2 pixels)
FINISH_REMAINDER:
//
// One pixel (edi == 1) or two pixels (edi == 0) left.
//
jnz short ONE_PIXEL_LEFT
//
// Two pixels left, only step texture co-ordinates once.
//
movzx eax,word ptr[edx + edi*2 - 4] // Get screen pixel 1.
paddd mm7,mm6 // Step U,V
movzx ebx,word ptr[edx + edi*2 - 2] // Get screen pixel 2.
and eax,ebp // And p1 with u2WaterMask.
mov edx,dword ptr[qIndexTemp] // Get texture index 1.
and ebx,ebp // And p2 with u2WaterMask.
mov ebp,dword ptr[qIndexTemp+4] // Get texture index 2.
movzx edx,word ptr[esi + edx*2 + 1] // Lookup texel 1.
movzx ebp,word ptr[esi + ebp*2 + 1] // Lookup texel 2.
or eax,edx // Combine alhpa and screen pixel.
mov edx,[pvBaseOfLine] // Reload base of line pointer.
or ebx,ebp // Combine alhpa and screen pixel.
mov ebp,[u4WaterMask] // Re-load water alpha mask value.
movzx eax,word ptr[ecx + eax*2 + 1] // Lookup through alpha water table.
movzx ebx,word ptr[ecx + ebx*2 + 1] // Lookup through alpha water table.
mov [edx + edi*2 - 4],ax // Store pixel 1
mov [edx + edi*2 - 2],bx // Store pixel 2
mov eax,[i_pixel] // Load remaining length.
jmp short END_OF_SPAN
ONE_PIXEL_LEFT:
//
// One pixel left, don't step texture co-ordinates.
//
movzx eax,word ptr[edx + edi*2 - 4] // Get screen pixel 1.
mov ebx,dword ptr[qIndexTemp] // Get texture index 1.
and eax,ebp // And p1 with u2WaterMask.
movzx ebx,word ptr[esi + ebx*2 + 1] // Lookup texel 1.
or eax,ebx // Combine alhpa and screen pixel.
movzx eax,word ptr[ecx + eax*2 + 1] // Lookup through alpha water table.
mov [edx + edi*2 - 4],ax // Store pixel 1
mov eax,[i_pixel] // Load remaining length.
END_OF_SPAN:
// See if there are any pixels left.
cmp eax,0
jz short END_OF_SCANLINE
//
// Do perspective correction and looping.
//
#ifdef __MWERKS__
#include "pseclamp3.inl"
#else
PERSPECTIVE_SCANLINE_EPILOGUE_CLAMP_3DX
#endif
jmp SUBDIVISION_LOOP
END_OF_SCANLINE:
//
// Increment the base edge.
//
pop ebp
mov esi,[pdtri] // Pointer to polygon object.
mov ecx,[pscan] // Pointer to scanline object.
// Step length, line starting address.
mov edx,[esi]CDrawPolygonBase.fxLineLength.i4Fx
mov edi,[esi]CDrawPolygonBase.iLineStartIndex
add edx,[esi]CDrawPolygonBase.fxDeltaLineLength.i4Fx
add edi,gsGlobals.u4LinePixels
mov eax,[ecx]TWaterPersp.fxX.i4Fx
mov [esi]CDrawPolygonBase.fxLineLength.i4Fx,edx
mov ebx,[ecx]TWaterPersp.fxXDifference.i4Fx
mov [esi]CDrawPolygonBase.iLineStartIndex,edi
// Step edge values.
movq mm0,[ecx]TWaterPersp.indCoord.fUInvZ
movq mm2,[tvEdgeStep.UInvZ]
movd mm1,[ecx]TWaterPersp.indCoord.fInvZ
movd mm3,[tvEdgeStep.InvZ]
pfadd (m0,m2)
mov edi,[fx_diff]
pfadd (m1,m3)
add eax,[fx_inc]
add ebx,edi
jge short NO_UNDERFLOW
// Underflow.
// Add borrow/carry adjustments to U,V,Z.
movq mm2,[tvNegAdj.UInvZ]
add ebx,0x00010000
movd mm3,[tvNegAdj.InvZ]
pfadd (m0,m2)
pfadd (m1,m3)
jmp short FINISH_LOOPING
NO_UNDERFLOW:
cmp ebx,0x00010000
jl short FINISH_LOOPING
// Overflow.
// Add borrow/carry adjustments to U,V,Z.
movq mm2,[tvNegAdj.UInvZ]
sub ebx,0x00010000
movd mm3,[tvNegAdj.InvZ]
pfadd (m0,m2)
pfadd (m1,m3)
FINISH_LOOPING:
// Save values and Y Loop control.
movq [ecx]TWaterPersp.indCoord.fUInvZ,mm0
movd [ecx]TWaterPersp.indCoord.fInvZ,mm1
mov [ecx]TWaterPersp.fxX.i4Fx,eax
mov edx,[esi]CDrawPolygonBase.iY
mov [ecx]TWaterPersp.fxXDifference.i4Fx,ebx
mov ebx,[esi]CDrawPolygonBase.iYTo
inc edx
mov [esi]CDrawPolygonBase.iY,edx
cmp edx,ebx
jl Y_LOOP
// Done with MMX/3DX.
femms
}
}
//*****************************************************************************************
//
// Linear, alpha texture.
//
//**********************************
void DrawSubtriangle(TWaterLinear* pscan, CDrawPolygon<TWaterLinear>* pdtri)
{
typedef TWaterLinear::TIndex prevent_internal_compiler_errors;
static CDrawPolygon<TWaterLinear>* pdtriGlbl;
static TWaterLinear* pscanGlbl;
static PackedFloatUV pf_texture_inc;
TWaterLinear* plinc = &pdtri->pedgeBase->lineIncrement;
__asm
{
// Get ready to do MMX/3DX.
femms
mov edi,[plinc] // Pointer to scanline increment.
mov esi,[pdtri] // Pointer to polygon object.
push ebp // Save base pointer.
mov eax,[pscan] // Pointer to scanline object.
mov pdtriGlbl,esi
//
// Local copies of edge stepping values.
//
// fx_inc = pdtri->pedgeBase->lineIncrement.fxX;
// fx_diff = pdtri->pedgeBase->lineIncrement.fxXDifference;
// pf_texture_inc = pdtri->pedgeBase->lineIncrement.indCoord.pfIndex;
// pdtriGlbl = pdtri;
// pscanGlbl = pscan;
// fx_gour_inc = pdtri->pedgeBase->lineIncrement.gourIntensity.fxIntensity;
//
mov ebx,[edi]TWaterLinear.fxX
mov pscanGlbl,eax
mov ecx,[edi]TWaterLinear.fxXDifference
mov fx_inc,ebx
movq mm0,[edi]TWaterLinear.indCoord.pfIndex
mov fx_diff,ecx
movq [pf_texture_inc],mm0
//
// Setup:
//
// mm2 = qMFactor = width,1,width,1
// mm3 = qUVMasks
// mm6 = uvslope
//
movd mm1,[iTexWidth] // 0,0,0,Width
movd mm2,[u4OneOne] // 0,0,1,1
punpcklwd mm1,mm1 // 0,0,Width,Width
movq mm6,[pfxDeltaTex] // Load texture slopes.
punpcklwd mm2,mm1 // Width,1,Width,1
movq mm7,[eax]TWaterLinear.indCoord.pfIndex
//
// Iterate through the scanlines that intersect the subtriangle.
//
Y_LOOP:
mov ebx,[bEvenScanlinesOnly]
mov edx,[esi]CDrawPolygonBase.iY
// Check for odd scan lines here and skip if even
and edx,ebx
jnz short END_OF_SCANLINE
mov ebx,[eax]TWaterLinear.fxX.i4Fx
mov ecx,[esi]CDrawPolygonBase.fxLineLength.i4Fx
mov edi,ebx
mov edx,gsGlobals.pvScreen
add ebx,ecx
sar edi,16
mov ecx,[esi]CDrawPolygonBase.iLineStartIndex
sar ebx,16
add ecx,ebx
lea edx,[edx + ecx*2]
sub edi,ebx
jge short END_OF_SCANLINE // no pixels to draw
//---------------------------------------------------------------------------
// Draw the scanline.
//
// eax = texel_index2 ebx = texel_index2
// ecx = clut pointer edx = dest_base_ptr
// esi = texture_base_ptr edi = pixel_offset & count
// ebp = alpha index mask
//
// mm0 = temp mm1 = temp
// mm2 = mfactor mm3 = uvmask
// mm6 = uvslope mm7 = uv (stepped once)
//
pf2id (m7,m7) // Convert texture values to 16.16 fixed.
mov esi,[pvTextureBitmap] // Load texture base pointer.
movq mm0,mm7 // Copy U1,V1
paddd mm7,mm6 // Step U,V
psrad mm0,16 // Shift for integer U1,V1
movq mm1,mm7 // Copy U2,V2
mov ecx,[pu2WaterAlpha] // Water alpha table.
psrad mm1,16 // Shift for integer U2,V2
packssdw mm0,mm1 // Pack integer texture values
movzx ebp,[u2WaterMask] // Load water alpha mask.
pmaddwd mm0,mm2 // Compute texture indicies.
mov [pvBaseOfLine],edx // Save base of scanline pointer.
dec esi // Hack to force SIB + offset in loop
mov [u4WaterMask],ebp // Save zero extended version of u2WaterMask.
dec ecx // Hack to force SIB + offset in loop
movq [qIndexTemp],mm0 // Save texture indicies.
//
// Make sure we have more than 2 pixels left.
//
add edi,2
jl short INNER_LOOP_2P
jmp FINISH_REMAINDER
// Align start of loop to 1 past the beginning of a cache line.
ALIGN 16
nop
//
// Do two pixels at a time.
//
// mm0 = packed & masked U1,V1,U2,V2
// mm7 is stepped once.
//
INNER_LOOP_2P:
movzx eax,word ptr[edx + edi*2 - 4] // Get screen pixel 1.
paddd mm7,mm6 // Step U,V
movzx ebx,word ptr[edx + edi*2 - 2] // Get screen pixel 2.
movq mm0,mm7 // Copy U1,V1
psrad mm0,16 // Shift for integer U1,V1
paddd mm7,mm6 // Step U,V
and eax,ebp // And p1 with u2WaterMask.
mov edx,dword ptr[qIndexTemp] // Get texture index 1.
and ebx,ebp // And p2 with u2WaterMask.
mov ebp,dword ptr[qIndexTemp+4] // Get texture index 2.
movzx edx,word ptr[esi + edx*2 + 1] // Lookup texel 1.
movq mm1,mm7 // Copy U2,V2
movzx ebp,word ptr[esi + ebp*2 + 1] // Lookup texel 2.
psrad mm1,16 // Shift for integer U2,V2
packssdw mm0,mm1 // Pack integer texture values.
or eax,edx // Combine alhpa and screen pixel.
mov edx,[pvBaseOfLine] // Reload base of line pointer.
or ebx,ebp // Combine alhpa and screen pixel.
mov ebp,[u4WaterMask] // Re-load water alpha mask value.
movzx eax,word ptr[ecx + eax*2 + 1] // Lookup through alpha water table.
pmaddwd mm0,mm2 // Compute texture indicies.
movzx ebx,word ptr[ecx + ebx*2 + 1] // Lookup through alpha water table.
movq [qIndexTemp],mm0 // Save texture indicies.
mov [edx + edi*2 - 4],ax // Store pixel 1
mov [edx + edi*2 - 2],bx // Store pixel 2
add edi,2 // Inrcement index by 2
jl short INNER_LOOP_2P // Loop (while >2 pixels)
FINISH_REMAINDER:
//
// One pixel (edi == 1) or two pixels (edi == 0) left.
//
jnz short ONE_PIXEL_LEFT
//
// Two pixels left, only step texture co-ordinates once.
//
movzx eax,word ptr[edx + edi*2 - 4] // Get screen pixel 1.
movzx ebx,word ptr[edx + edi*2 - 2] // Get screen pixel 2.
and eax,ebp // And p1 with u2WaterMask.
mov edx,dword ptr[qIndexTemp] // Get texture index 1.
and ebx,ebp // And p2 with u2WaterMask.
mov ebp,dword ptr[qIndexTemp+4] // Get texture index 2.
movzx edx,word ptr[esi + edx*2 + 1] // Lookup texel 1.
movzx ebp,word ptr[esi + ebp*2 + 1] // Lookup texel 2.
or eax,edx // Combine alhpa and screen pixel.
mov edx,[pvBaseOfLine] // Reload base of line pointer.
or ebx,ebp // Combine alhpa and screen pixel.
mov ebp,[u4WaterMask] // Re-load water alpha mask value.
movzx eax,word ptr[ecx + eax*2 + 1] // Lookup through alpha water table.
movzx ebx,word ptr[ecx + ebx*2 + 1] // Lookup through alpha water table.
mov [edx + edi*2 - 4],ax // Store pixel 1
mov [edx + edi*2 - 2],bx // Store pixel 2
jmp short END_OF_SCANLINE
ONE_PIXEL_LEFT:
//
// One pixel left, don't step texture co-ordinates.
//
movzx eax,word ptr[edx + edi*2 - 4] // Get screen pixel 1.
mov ebx,dword ptr[qIndexTemp] // Get texture index 1.
and eax,ebp // And p1 with u2WaterMask.
movzx ebx,word ptr[esi + ebx*2 + 1] // Lookup texel 1.
or eax,ebx // Combine alhpa and screen pixel.
movzx eax,word ptr[ecx + eax*2 + 1] // Lookup through alpha water table.
mov [edx + edi*2 - 4],ax // Store pixel 1
// -------------------------------------------------------------------------
// Increment the base edge.
//
END_OF_SCANLINE:
mov eax,[pscanGlbl]
movq mm1,[pf_texture_inc]
movq mm7,[eax]TWaterLinear.indCoord.pfIndex
mov ebx,[eax]TWaterLinear.fxXDifference
pfadd (m7,m1)
add ebx,[fx_diff]
jge short NO_UNDERFLOW
// Undeflow of fxXDifference.
add ebx,0x00010000
movq mm1,[pfNegD]
pfadd (m7,m1)
jmp short EDGE_DONE
NO_UNDERFLOW:
cmp ebx,0x00010000
jl short EDGE_DONE
// Overflow of fxXDifference.
sub ebx,0x00010000
movq mm1,[pfNegD]
pfadd (m7,m1)
EDGE_DONE:
// Store modified variables and do looping.
// Step length, line starting address.
mov esi,[pdtriGlbl]
mov [eax]TWaterLinear.fxXDifference,ebx
movq [eax]TWaterLinear.indCoord.pfIndex,mm7
mov ebx,[esi]CDrawPolygonBase.fxLineLength.i4Fx
mov ecx,[esi]CDrawPolygonBase.iLineStartIndex
add ebx,[esi]CDrawPolygonBase.fxDeltaLineLength.i4Fx
add ecx,gsGlobals.u4LinePixels
mov [esi]CDrawPolygonBase.fxLineLength.i4Fx,ebx
mov [esi]CDrawPolygonBase.iLineStartIndex,ecx
mov ecx,[eax]TWaterLinear.fxX
mov edx,[fx_inc]
add ecx,edx
mov edx,[esi]CDrawPolygonBase.iY
mov [eax]TWaterLinear.fxX,ecx
inc edx
mov ebx,[esi]CDrawPolygonBase.iYTo
mov [esi]CDrawPolygonBase.iY,edx
cmp edx,ebx
jl Y_LOOP
// Done with MMX/3DX.
femms
pop ebp // Restore base pointer.
}
}
//*****************************************************************************************
//
// Perspective, stippled texture.
//
void DrawSubtriangle(TStippleTexPersp* pscan, CDrawPolygon<TStippleTexPersp>* pdtri)
{
TStippleTexPersp* plinc = &pdtri->pedgeBase->lineIncrement;
Assert(pu2WaterAlpha);
__asm
{
// Get ready to do MMX/3DX.
femms
//
// Local copies of edge stepping values.
//
// fx_inc = pdtri->pedgeBase->lineIncrement.fxX;
// fx_diff = pdtri->pedgeBase->lineIncrement.fxXDifference;
// f_inc_uinvz = pdtri->pedgeBase->lineIncrement.indCoord.fUInvZ;
// f_inc_vinvz = pdtri->pedgeBase->lineIncrement.indCoord.fVInvZ;
// f_inc_invz = pdtri->pedgeBase->lineIncrement.indCoord.fInvZ;
//
mov eax,[plinc]
mov esi,[pdtri] // Pointer to polygon object.
mov ecx,[pscan] // Pointer to scanline object.
mov ebx,[eax]TStippleTexPersp.fxX
mov edx,[eax]TStippleTexPersp.fxXDifference
mov fx_inc,ebx
movq mm0,[eax]TStippleTexPersp.indCoord.fUInvZ
mov fx_diff,edx
mov ebx,[eax]TStippleTexPersp.indCoord.fInvZ
movq [tvEdgeStep.UInvZ],mm0
mov [tvEdgeStep.InvZ],ebx
//
// Setup:
// QWORD qMFactor = width,1,width,1
// Load global texture values.
//
movd mm3,[iTexWidth] // 0,0,0,Width
movd mm4,[u4OneOne] // 0,0,1,1
punpcklwd mm3,mm3 // 0,0,Width,Width
punpcklwd mm4,mm3 // Width,1,Width,1
movq mm0,[ecx]TStippleTexPersp.indCoord.fUInvZ // mm0 = (V/Z,U/Z)
movq [qMFactor],mm4 // Save mfactor
movd mm1,[ecx]TStippleTexPersp.indCoord.fInvZ // mm1 = (?,1/Z)
//
// Iterate through the scanlines that intersect the subtriangle.
//
// esi,ecx,mm0,mm1 setup.
//
Y_LOOP:
mov eax,[esi]CDrawPolygonBase.iY
mov ebx,[bEvenScanlinesOnly]
// Check to see if we sould skip this scanline.
and eax,ebx
jnz END_OF_SCANLINE
//
// Setup for prespective correction and looping.
//
//PERSPECTIVE_SCANLINE_PROLOGUE_CLAMP_3DX(TStippleTexPersp)
//
// Determine the start and end of the scanline.
//
mov ebx,[ecx]TStippleTexPersp.fxX.i4Fx
mov eax,[esi]CDrawPolygonBase.fxLineLength.i4Fx
mov edx,[esi]CDrawPolygonBase.iLineStartIndex
add ebx,eax
mov eax,[ecx]TStippleTexPersp.fxX.i4Fx
sar ebx,16
sar eax,16
add edx,ebx
sub eax,ebx // eax == i_pixel
jge END_OF_SCANLINE
mov [i_screen_index],edx // Save scanline index.
mov ebx,[ecx]TStippleTexPersp.fxX.i4Fx // Fractional X.
sar ebx,16 // Integer X.
mov edi,[esi]CDrawPolygonBase.iY // Integer Y.
// Load span increments.
movq mm2,[tvDEdge.UInvZ] // Load V,U
xor ebx,edi // X xor Y
movd mm3,[tvDEdge.InvZ] // Load Z
mov [i_pixel],eax // Save negative length of scanline.
mov edi,[iSubdivideLen]
// Skip over a pixel if ((y xor x) & 1).
test ebx,1
jz NO_SKIP
inc eax // Increment i_pixel
jz END_OF_SCANLINE
// Increment starting texture values.
movd mm5,[fInvSubdivideLen] // 1/SubDivideLen
movq mm4,mm5 // Save a copy.
pfmul (m5,m3) // Per pixel z step.
punpckldq mm4,mm4 // 1/SubDivideLen | 1/SubDivideLen
pfadd (m1,m5) // Add to starting z.
pfmul (m4,m2) // Per pixel uv step.
pfadd (m0,m4) // Add to staring uv.
mov [i_pixel],eax // Save update i_pixel
NO_SKIP:
// scan line is +ve
add eax,edi // eax = i_pixel + SubdivideLen
jle short DONE_DIVIDE_PIXEL
//
// Subdivision is smaller than iSubdivideLen
//
// Adjust span increments by -i_pixel * fInvSubdivideLen
//
mov edi,[i_pixel] // Integer width of span.
xor eax,eax // Remaining width.
neg edi
movd mm4,edi // -i_pixel
pi2fd (m4,m4) // Convert to fp.
movd mm5,[fInvSubdivideLen] // 1/SubDivideLen
pfmul (m4,m5) // -i_pixel * fInvSubdivideLen
punpckldq mm4,mm4
pfmul (m2,m4) // Adjust V,U increments.
pfmul (m3,m4) // Adjust Z increment.
DONE_DIVIDE_PIXEL:
//
// Compute current U,V
// Step fGUInvZ,fGVInvZ,fGInvZ
//
pfrcp (m4,m1) // f_z = mm4 = 1/fGInvZ
mov [iNextSubdivide],eax // Save length remaining.
pfadd (m3,m1) // Step fGInvZ
pfadd (m2,m0) // Step fGUInvZ,fGVInvZ
movd [tvCurUVZ.InvZ],mm3 // Save updated 1/Z
pfmul (m4,m0) // mm4 = V1,U1
pfrcp (m0,m3) // f_next_z = mm0 = 1/fGInvZ
movq [tvCurUVZ.UInvZ],mm2 // Save updated U/Z,V/Z
movd mm1,float ptr[fInverseIntTable+edi*4] // Reciprocal of span width.
pfmul (m0,m2) // mm0 = V2,U2
movq mm2,[pfFixed16Scale] // Load fixed point scale factors.
movq mm3,[pfTexEdgeTolerance]
movq mm5,[cvMaxCoords]
pfmax (m0,m3) // Clamp U1,V1 to >= fTexEdgeTolerance
pfmin (m0,m5) // Clamp U1 < fTexWidth, V1 < fTexHeight
pfmax (m4,m3) // Clamp U1,V1 to >= fTexEdgeTolerance
pfmin (m4,m5) // Clamp U1 < fTexWidth, V1 < fTexHeight
punpckldq mm1,mm1 // Duplicate reciprocal of span width.
movq [pfCurUV],mm0 // Save ending U,V
pfsub (m0,m4) // mm0 = V2-V1,U2-U1
pfmul (m4,m2) // Scale to starting U,V 16.16
mov edi,[i_pixel] // edi = current i_pixel
mov [i_pixel],eax // Save updated i_pixel.
pfmul (m0,m1) // DV*1/Width,DU*1/Width
pf2id (m7,m4) // Starting V,U in mm7
sub edi,eax // edi = inner loop count
mov ebx,[i_screen_index] // Load scanline offset.
pfmul (m0,m2) // Scale U,V slope to 16.16
mov edx,gsGlobals.pvScreen // Pointer the screen.
mov esi,[pvTextureBitmap] // Load texture base pointer.
add eax,ebx // Add scanline offset to i_pixel
pf2id (m6,m0) // VStep,UStep in mm6
lea edx,[edx+eax*2] // Base of span in edx.
SUBDIVISION_LOOP:
//---------------------------------------------------------------------------
// Draw the subdivision.
//
// mm6,mm7 = texture values.
//
// Setup registers:
//
// eax = texel_index2 ebx = texel_index2
// ecx = ??? edx = dest_base_ptr
// esi = texture_base_ptr edi = pixel_offset & count
// ebp = base pointer
//
// mm0 = temp mm1 = temp
// mm2 = mfactor mm3 = uvmask
// mm6 = uvslope mm7 = uv (stepped once)
//
movq mm0,mm7 // Copy U1,V1
paddd mm6,mm6 // Double Step.
paddd mm7,mm6 // Step U,V by 2
psrad mm0,16 // Shift for integer U1,V1
movq mm1,mm7 // Copy U2,V2
movq mm2,[qMFactor] // Load texture multipliers
psrad mm1,16 // Shift for integer U2,V2
packssdw mm0,mm1 // Pack integer texture values
dec esi // Hack to force SIB + offset in loop
pmaddwd mm0,mm2 // Compute texture indicies.
//
// Make sure we have more than 2 pixels left.
//
add edi,4
jl short INNER_LOOP_2P
jmp FINISH_REMAINDER
// Align start of loop to 0, 1, or 17 past the beginning of a cache line.
ALIGN 16
nop
//
// Do two pixels at a time.
//
// mm0 = packed & masked U1,V1,U2,V2
// mm7 is stepped once.
//
INNER_LOOP_2P:
movq [qIndexTemp],mm0 // Save texture indicies.
paddd mm7,mm6 // Step U,V by 2
mov eax,dword ptr[qIndexTemp] // Get texture index 1.
movq mm0,mm7 // Copy U1,V1
mov ebx,dword ptr[qIndexTemp+4] // Get texture index 2.
psrad mm0,16 // Shift for integer U1,V1
movzx eax,word ptr[esi + eax*2 + 1] // Lookup texel 1.
paddd mm7,mm6 // Step U,V by 2
movzx ebx,word ptr[esi + ebx*2 + 1] // Lookup texel 2.
movq mm1,mm7 // Copy U2,V2
psrad mm1,16 // Shift for integer U2,V2
packssdw mm0,mm1 // Pack integer texture values.
pmaddwd mm0,mm2 // Compute texture indicies.
mov [edx + edi*2 - 8],ax // Store pixel 1
mov [edx + edi*2 - 4],bx // Store pixel 2
add edi,4 // Inrcement index by 4
jl short INNER_LOOP_2P // Loop (while >4 pixels)
FINISH_REMAINDER:
//
// One (edi == 3), two (edi == 2), three (edi == 1) or four (edi == 0) pixels left.
//
cmp edi,2
jge ONE_OR_TWO_PIXELS_LEFT
//
// Draw two pixels, step uv by 2.
//
movq [qIndexTemp],mm0 // Save texture indicies.
paddd mm7,mm6 // Step U,V by 2
mov eax,dword ptr[qIndexTemp] // Get texture index 1.
mov ebx,dword ptr[qIndexTemp+4] // Get texture index 2.
movzx eax,word ptr[esi + eax*2 + 1] // Lookup texel 1.
movzx ebx,word ptr[esi + ebx*2 + 1] // Lookup texel 2.
mov [edx + edi*2 - 8],ax // Store pixel 1
mov [edx + edi*2 - 4],bx // Store pixel 2
mov eax,[i_pixel] // Load remaining length.
jmp short END_OF_SPAN
ONE_OR_TWO_PIXELS_LEFT:
//
// Draw one pixel, don't step uv.
//
movq [qIndexTemp],mm0 // Save texture indicies.
mov eax,[i_pixel] // Load remaining length.
mov ebx,dword ptr[qIndexTemp] // Get texture index 1.
movzx ebx,word ptr[esi + ebx*2 + 1] // Lookup texel 1.
mov [edx + edi*2 - 8],bx // Store pixel 1
END_OF_SPAN:
// See if there are any pixels left.
cmp eax,0
jz short END_OF_SCANLINE
//
// Do perspective correction and looping.
//
//PERSPECTIVE_SCANLINE_EPILOGUE_CLAMP_3DX
mov edi,[iSubdivideLen]
// Load last texture values.
movq mm0,[tvCurUVZ.UInvZ] // mm0 = (V/Z,U/Z)
movd mm1,[tvCurUVZ.InvZ] // mm1 = (?,1/Z)
// Load span increments.
movq mm2,[tvDEdge.UInvZ] // V,U
movd mm3,[tvDEdge.InvZ] // Z
// scan line is +ve
add eax,edi // eax = i_pixel + SubdivideLen
jle short DONE_DIVIDE_PIXEL_END
//
// Subdivision is smaller than iSubdivideLen
//
// Adjust span increments by -i_pixel * fInvSubdivideLen
//
mov edi,[i_pixel] // Integer width of span.
xor eax,eax // Remaining width.
neg edi
movd mm4,edi // -i_pixel
pi2fd (m4,m4) // Convert to fp.
movd mm5,[fInvSubdivideLen] // 1/SubDivideLen
pfmul (m4,m5) // -i_pixel * fInvSubdivideLen
punpckldq mm4,mm4
pfmul (m2,m4) // Adjust V,U increments.
pfmul (m3,m4) // Adjust Z increment.
DONE_DIVIDE_PIXEL_END:
//
// Compute current U,V
// Step fGUInvZ,fGVInvZ,fGInvZ
//
pfadd (m3,m1) // Step fGInvZ
mov [iNextSubdivide],eax // Save length remaining.
pfadd (m2,m0) // Step fGUInvZ,fGVInvZ
movd [tvCurUVZ.InvZ],mm3 // Save updated fGInvZ
pfrcp (m0,m3) // f_z = mm0 = 1/fGInvZ
movq mm4,[pfCurUV] // Load last U,V
movq [tvCurUVZ.UInvZ],mm2 // Save updated fGUInvZ,fGVInvZ
movd mm1,float ptr[fInverseIntTable+edi*4] // Reciprocal of span width.
pfmul (m0,m2) // mm0 = V2,U2
movq mm2,[pfFixed16Scale] // Load fixed point scale factors.
movq mm3,[pfTexEdgeTolerance]
movq mm5,[cvMaxCoords]
pfmax (m0,m3) // Clamp U1,V1 to >= fTexEdgeTolerance
pfmin (m0,m5) // Clamp U1 < fTexWidth, V1 < fTexHeight
movq [pfCurUV],mm0 // Save current U,V
punpckldq mm1,mm1 // Duplicate across entire register.
pfsub (m0,m4) // V2-V1,U2-U1
mov edi,[i_pixel] // edi = current i_pixel
mov [i_pixel],eax // Save updated i_pixel.
mov edx,gsGlobals.pvScreen // Pointer the screen.
pfmul (m0,m1) // DV*1/Width,DU*1/Width
mov ebx,[i_screen_index] // Load scanline offset.
sub edi,eax // edi = inner loop count
mov esi,[pvTextureBitmap] // Load texture base pointer.
pfmul (m0,m2) // Scale to 16.16
add eax,ebx // Add scanline offset to i_pixel
lea edx,[edx+eax*2] // Base of span in edx.
pf2id (m6,m0) // VStep,UStep in mm6
jmp SUBDIVISION_LOOP
END_OF_SCANLINE:
//
// Increment the base edge.
//
mov esi,[pdtri] // Pointer to polygon object.
mov ecx,[pscan] // Pointer to scanline object.
// Step length, line starting address.
mov edx,[esi]CDrawPolygonBase.fxLineLength.i4Fx
mov edi,[esi]CDrawPolygonBase.iLineStartIndex
add edx,[esi]CDrawPolygonBase.fxDeltaLineLength.i4Fx
add edi,gsGlobals.u4LinePixels
mov eax,[ecx]TStippleTexPersp.fxX.i4Fx
mov [esi]CDrawPolygonBase.fxLineLength.i4Fx,edx
mov ebx,[ecx]TStippleTexPersp.fxXDifference.i4Fx
mov [esi]CDrawPolygonBase.iLineStartIndex,edi
// Step edge values.
movq mm0,[ecx]TStippleTexPersp.indCoord.fUInvZ
movq mm2,[tvEdgeStep.UInvZ]
movd mm1,[ecx]TStippleTexPersp.indCoord.fInvZ
movd mm3,[tvEdgeStep.InvZ]
pfadd (m0,m2)
mov edi,[fx_diff]
pfadd (m1,m3)
add eax,[fx_inc]
add ebx,edi
jge short NO_UNDERFLOW
// Underflow.
// Add borrow/carry adjustments to U,V,Z.
movq mm2,[tvNegAdj.UInvZ]
add ebx,0x00010000
movd mm3,[tvNegAdj.InvZ]
pfadd (m0,m2)
pfadd (m1,m3)
jmp short FINISH_LOOPING
NO_UNDERFLOW:
cmp ebx,0x00010000
jl short FINISH_LOOPING
// Overflow.
// Add borrow/carry adjustments to U,V,Z.
movq mm2,[tvNegAdj.UInvZ]
sub ebx,0x00010000
movd mm3,[tvNegAdj.InvZ]
pfadd (m0,m2)
pfadd (m1,m3)
FINISH_LOOPING:
// Save values and Y Loop control.
movq [ecx]TStippleTexPersp.indCoord.fUInvZ,mm0
movd [ecx]TStippleTexPersp.indCoord.fInvZ,mm1
mov [ecx]TStippleTexPersp.fxX.i4Fx,eax
mov edx,[esi]CDrawPolygonBase.iY
mov [ecx]TStippleTexPersp.fxXDifference.i4Fx,ebx
mov ebx,[esi]CDrawPolygonBase.iYTo
inc edx
mov [esi]CDrawPolygonBase.iY,edx
cmp edx,ebx
jl Y_LOOP
// Done with MMX/3DX.
femms
}
}
//*****************************************************************************************
//
// Linear, stippled texture.
//
//**********************************
void DrawSubtriangle(TStippleTexLinear* pscan, CDrawPolygon<TStippleTexLinear>* pdtri)
{
typedef TStippleTexLinear::TIndex prevent_internal_compiler_errors;
static CDrawPolygon<TStippleTexLinear>* pdtriGlbl;
static TStippleTexLinear* pscanGlbl;
static PackedFloatUV pf_texture_inc;
TStippleTexLinear* plinc = &pdtri->pedgeBase->lineIncrement;
__asm
{
// Get ready to do MMX/3DX.
femms
mov edi,[plinc] // Pointer to scanline increment.
mov esi,[pdtri] // Pointer to polygon object.
mov eax,[pscan] // Pointer to scanline object.
mov pdtriGlbl,esi
//
// Local copies of edge stepping values.
//
// fx_inc = pdtri->pedgeBase->lineIncrement.fxX;
// fx_diff = pdtri->pedgeBase->lineIncrement.fxXDifference;
// pf_texture_inc = pdtri->pedgeBase->lineIncrement.indCoord.pfIndex;
// pdtriGlbl = pdtri;
// pscanGlbl = pscan;
// fx_gour_inc = pdtri->pedgeBase->lineIncrement.gourIntensity.fxIntensity;
//
mov ebx,[edi]TStippleTexLinear.fxX
mov pscanGlbl,eax
mov ecx,[edi]TStippleTexLinear.fxXDifference
mov fx_inc,ebx
movq mm0,[edi]TStippleTexLinear.indCoord.pfIndex
mov fx_diff,ecx
movq [pf_texture_inc],mm0
//
// Setup:
//
// mm2 = qMFactor = width,1,width,1
// mm3 = qUVMasks
// mm6 = uvslope
//
movd mm1,[iTexWidth] // 0,0,0,Width
movd mm2,[u4OneOne] // 0,0,1,1
punpcklwd mm1,mm1 // 0,0,Width,Width
movq mm6,[pfxDeltaTex] // Load texture slopes.
punpcklwd mm2,mm1 // Width,1,Width,1
movq mm7,[eax]TStippleTexLinear.indCoord.pfIndex
//
// Iterate through the scanlines that intersect the subtriangle.
//
Y_LOOP:
mov ebx,[bEvenScanlinesOnly]
mov edx,[esi]CDrawPolygonBase.iY
// Check for odd scan lines here and skip if even
and edx,ebx
jnz short END_OF_SCANLINE
mov ebx,[eax]TStippleTexLinear.fxX.i4Fx
mov ecx,[esi]CDrawPolygonBase.fxLineLength.i4Fx
mov edi,ebx
mov edx,gsGlobals.pvScreen
add ebx,ecx
sar edi,16
mov ecx,[esi]CDrawPolygonBase.iLineStartIndex
sar ebx,16
add ecx,ebx
lea edx,[edx + ecx*2]
sub edi,ebx
jge short END_OF_SCANLINE // no pixels to draw
//---------------------------------------------------------------------------
// Draw the scanline.
//
// eax = texel_index1 ebx = texel_index2
// ecx = ??? edx = dest_base_ptr
// esi = texture_base_ptr edi = pixel_offset & count
//
// mm0 = temp mm1 = temp
// mm2 = mfactor mm3 = uvmask
// mm5 = uvslope*2
// mm6 = uvslope mm7 = uv
//
pf2id (m7,m7) // Convert texture values to 16.16 fixed.
mov ebx,[eax]TStippleTexPersp.fxX.i4Fx // Fractional X.
movq mm5,mm6 // Copy step.
mov ecx,[esi]CDrawPolygonBase.iY // Integer Y.
paddd mm5,mm5 // Double step.
sar ebx,16 // Integer X.
// if ((y xor x) & 1) skip a pixel.
xor ebx,ecx
and ebx,1
jz NO_SKIP
paddd mm7,mm6 // Step U,V
inc edi
jz END_OF_SCANLINE
NO_SKIP:
movq mm0,mm7 // Copy U1,V1
paddd mm7,mm5 // Step U,V by 2
psrad mm0,16 // Shift for integer U1,V1
movq mm1,mm7 // Copy U2,V2
psrad mm1,16 // Shift for integer U2,V2
mov esi,[pvTextureBitmap] // Load texture base pointer.
packssdw mm0,mm1 // Pack integer texture values
dec esi // Hack to force SIB + offset in loop
pmaddwd mm0,mm2 // Compute texture indicies.
//
// Make sure we have more than 2 pixels left.
//
add edi,4
jl short INNER_LOOP_2P
jmp FINISH_REMAINDER
// Align start of loop to 0, 1 or 17 past the beginning of a cache line.
ALIGN 16
nop
//
// Do two pixels at a time.
//
// mm0 = packed & masked U1,V1,U2,V2
// mm7 is stepped once.
//
INNER_LOOP_2P:
movq [qIndexTemp],mm0 // Save texture indicies.
paddd mm7,mm5 // Step U,V by 2
mov eax,dword ptr[qIndexTemp] // Get texture index 1.
movq mm0,mm7 // Copy U1,V1
mov ebx,dword ptr[qIndexTemp+4] // Get texture index 2.
psrad mm0,16 // Shift for integer U1,V1
movzx eax,word ptr[esi + eax*2 + 1] // Lookup texel 1.
paddd mm7,mm5 // Step U,V by 2
movzx ebx,word ptr[esi + ebx*2 + 1] // Lookup texel 2.
movq mm1,mm7 // Copy U2,V2
psrad mm1,16 // Shift for integer U2,V2
packssdw mm0,mm1 // Pack integer texture values.
pmaddwd mm0,mm2 // Compute texture indicies.
mov [edx + edi*2 - 8],ax // Store pixel 1
mov [edx + edi*2 - 4],bx // Store pixel 2
add edi,4 // Increment index by 4
jl short INNER_LOOP_2P // Loop (while >4 pixels)
FINISH_REMAINDER:
//
// One (edi == 3), two (edi == 2), three (edi == 1) or four (edi == 0) pixels left.
//
cmp edi,2
jge ONE_OR_TWO_PIXELS_LEFT
//
// Draw two pixels.
//
movq [qIndexTemp],mm0 // Save texture indicies.
mov eax,dword ptr[qIndexTemp] // Get texture index 1.
mov ebx,dword ptr[qIndexTemp+4] // Get texture index 2.
movzx eax,word ptr[esi + eax*2 + 1] // Lookup texel 1.
movzx ebx,word ptr[esi + ebx*2 + 1] // Lookup texel 2.
mov [edx + edi*2 - 8],ax // Store pixel 1
mov [edx + edi*2 - 4],bx // Store pixel 2
jmp short END_OF_SCANLINE
ONE_OR_TWO_PIXELS_LEFT:
//
// Draw one pixel.
//
movq [qIndexTemp],mm0 // Save texture indicies.
mov eax,dword ptr[qIndexTemp] // Get texture index 1.
movzx eax,word ptr[esi + eax*2 + 1] // Lookup texel 1.
mov [edx + edi*2 - 8],ax // Store pixel 1
// -------------------------------------------------------------------------
// Increment the base edge.
//
END_OF_SCANLINE:
mov eax,[pscanGlbl]
movq mm1,[pf_texture_inc]
movq mm7,[eax]TStippleTexLinear.indCoord.pfIndex
mov ebx,[eax]TStippleTexLinear.fxXDifference
pfadd (m7,m1)
add ebx,[fx_diff]
jge short NO_UNDERFLOW
// Undeflow of fxXDifference.
add ebx,0x00010000
movq mm1,[pfNegD]
pfadd (m7,m1)
jmp short EDGE_DONE
NO_UNDERFLOW:
cmp ebx,0x00010000
jl short EDGE_DONE
// Overflow of fxXDifference.
sub ebx,0x00010000
movq mm1,[pfNegD]
pfadd (m7,m1)
EDGE_DONE:
// Store modified variables and do looping.
// Step length, line starting address.
mov esi,[pdtriGlbl]
mov [eax]TStippleTexLinear.fxXDifference,ebx
movq [eax]TStippleTexLinear.indCoord.pfIndex,mm7
mov ebx,[esi]CDrawPolygonBase.fxLineLength.i4Fx
mov ecx,[esi]CDrawPolygonBase.iLineStartIndex
add ebx,[esi]CDrawPolygonBase.fxDeltaLineLength.i4Fx
add ecx,gsGlobals.u4LinePixels
mov [esi]CDrawPolygonBase.fxLineLength.i4Fx,ebx
mov [esi]CDrawPolygonBase.iLineStartIndex,ecx
mov ecx,[eax]TStippleTexLinear.fxX
mov edx,[fx_inc]
add ecx,edx
mov edx,[esi]CDrawPolygonBase.iY
mov [eax]TStippleTexLinear.fxX,ecx
inc edx
mov ebx,[esi]CDrawPolygonBase.iYTo
mov [esi]CDrawPolygonBase.iY,edx
cmp edx,ebx
jl Y_LOOP
// Done with MMX/3DX.
femms
}
}
#if (0)
//*********************************************************************************************
void DrawSubtriangle(TWaterPersp* pscan, CDrawPolygon<TWaterPersp>* pdtri)
{
typedef TWaterPersp::TPixel TDest;
Assert(pscan);
Assert(pdtri);
int i_x_from;
int i_x_to;
int i_screen_index;
int i_pixel;
// Iterate through the scanlines that intersect the subtriangle.
do
{
if (bRIGHT_TO_LEFT)
{
i_x_from = (pscan->fxX.i4Fx - pdtri->fxLineLength.i4Fx) >> 16;
i_x_to = pscan->fxX.i4Fx >> 16;
i_screen_index = pdtri->iLineStartIndex + i_x_from - 1;
i_pixel = i_x_to - i_x_from;
}
else
{
i_x_from = pscan->fxX.i4Fx >> 16;
i_x_to = (pscan->fxX.i4Fx + pdtri->fxLineLength.i4Fx) >> 16;
i_screen_index = pdtri->iLineStartIndex + i_x_to;
i_pixel = i_x_from - i_x_to;
}
// Draw if there are pixels to draw.
if (i_x_to > i_x_from && !(bEvenScanlinesOnly && ((pdtri->iY & 1) == 0)))
{
{
TWaterPersp::TIndex index(pscan->indCoord, i_pixel);
TDest* apix_screen = ((TDest*)pdtri->prasScreen->pSurface) + i_screen_index;
// Iterate left or right along the destination scanline.
for (;;)
{
// Do next subdivision.
int i_pixel_inner = index.i4StartSubdivision(i_pixel);
TDest* apix_screen_inner = apix_screen + i_pixel;
for (;;)
{
// Get an indexed alpha pixel.
uint16 u2_alpha = ((uint16*)pvTextureBitmap)[index.iGetIndex()];
++index;
// Get the screen pixel.
uint16 u2_screen = apix_screen_inner[i_pixel_inner];
// And off bits for the alpha mask.
u2_screen &= u2WaterMask;
// Or in bits for the alpha band.
u2_screen |= u2_alpha;
// Look up the alpha colour.
u2_screen = pu2WaterAlpha[u2_screen];
// Write the pixel back to the screen.
apix_screen_inner[i_pixel_inner] = u2_screen;
// Increment values.
i_pixel_inner += i4ScanlineDirection;
// Break from subdivision loop if there are no more pixels to render.
if (i_pixel_inner == 0)
break;
}
// Exit scanline routine if there are no more pixels to render.
if (i_pixel == 0)
break;
// Implement perspective correction.
index.UpdatePerspective(0);
}
}
}
// Increment the base edge.
++*pdtri->pedgeBase;
// Set the new length of the line to be rasterized.
pdtri->fxLineLength.i4Fx += pdtri->fxDeltaLineLength.i4Fx;
// Get new starting pixel TIndex for the scanline.
pdtri->iLineStartIndex += pdtri->prasScreen->iLinePixels;
}
while (++pdtri->iY < pdtri->iYTo);
}
//*********************************************************************************************
void DrawSubtriangle(TWaterLinear* pscan, CDrawPolygon<TWaterLinear>* pdtri)
{
typedef TWaterLinear::TPixel TDest;
Assert(pscan);
Assert(pdtri);
int i_x_from;
int i_x_to;
int i_screen_index;
int i_pixel;
// Iterate through the scanlines that intersect the subtriangle.
do
{
if (bRIGHT_TO_LEFT)
{
i_x_from = (pscan->fxX.i4Fx - pdtri->fxLineLength.i4Fx) >> 16;
i_x_to = pscan->fxX.i4Fx >> 16;
i_screen_index = pdtri->iLineStartIndex + i_x_from - 1;
i_pixel = i_x_to - i_x_from;
}
else
{
i_x_from = pscan->fxX.i4Fx >> 16;
i_x_to = (pscan->fxX.i4Fx + pdtri->fxLineLength.i4Fx) >> 16;
i_screen_index = pdtri->iLineStartIndex + i_x_to;
i_pixel = i_x_from - i_x_to;
}
// Draw if there are pixels to draw.
if (i_x_to > i_x_from && !(bEvenScanlinesOnly && ((pdtri->iY & 1) == 0)))
{
{
TWaterLinear::TIndex index(pscan->indCoord, i_pixel);
TDest* apix_screen = ((TDest*)pdtri->prasScreen->pSurface) + i_screen_index;
// Iterate left or right along the destination scanline.
for (;;)
{
// Do next subdivision.
int i_pixel_inner = index.i4StartSubdivision(i_pixel);
TDest* apix_screen_inner = apix_screen + i_pixel;
for (;;)
{
// Get an indexed alpha pixel.
uint16 u2_alpha = ((uint16*)pvTextureBitmap)[index.iGetIndex()];
++index;
// Get the screen pixel.
uint16 u2_screen = apix_screen_inner[i_pixel_inner];
// And off bits for the alpha mask.
u2_screen &= u2WaterMask;
// Or in bits for the alpha band.
u2_screen |= u2_alpha;
// Look up the alpha colour.
u2_screen = pu2WaterAlpha[u2_screen];
// Write the pixel back to the screen.
apix_screen_inner[i_pixel_inner] = u2_screen;
// Increment values.
i_pixel_inner += i4ScanlineDirection;
// Break from subdivision loop if there are no more pixels to render.
if (i_pixel_inner == 0)
break;
}
// Exit scanline routine if there are no more pixels to render.
if (i_pixel == 0)
break;
// Implement perspective correction.
index.UpdatePerspective(0);
}
}
}
// Increment the base edge.
++*pdtri->pedgeBase;
// Set the new length of the line to be rasterized.
pdtri->fxLineLength.i4Fx += pdtri->fxDeltaLineLength.i4Fx;
// Get new starting pixel TIndex for the scanline.
pdtri->iLineStartIndex += pdtri->prasScreen->iLinePixels;
}
while (++pdtri->iY < pdtri->iYTo);
}
#endif
// Restore default section.
#pragma code_seg()