mirror of
https://github.com/blendogames/thirtyflightsofloving.git
synced 2024-11-14 16:40:57 +00:00
879 lines
19 KiB
ArmAsm
879 lines
19 KiB
ArmAsm
//
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// d_spr8.s
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// x86 assembly-language horizontal 8-bpp transparent span-drawing code.
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//
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#include "qasm.h"
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#if id386
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//----------------------------------------------------------------------
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// 8-bpp horizontal span drawing code for polygons, with transparency.
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//----------------------------------------------------------------------
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.text
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// out-of-line, rarely-needed clamping code
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LClampHigh0:
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movl C(bbextents),%esi
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jmp LClampReentry0
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LClampHighOrLow0:
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jg LClampHigh0
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xorl %esi,%esi
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jmp LClampReentry0
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LClampHigh1:
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movl C(bbextentt),%edx
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jmp LClampReentry1
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LClampHighOrLow1:
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jg LClampHigh1
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xorl %edx,%edx
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jmp LClampReentry1
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LClampLow2:
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movl $2048,%ebp
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jmp LClampReentry2
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LClampHigh2:
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movl C(bbextents),%ebp
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jmp LClampReentry2
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LClampLow3:
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movl $2048,%ecx
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jmp LClampReentry3
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LClampHigh3:
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movl C(bbextentt),%ecx
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jmp LClampReentry3
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LClampLow4:
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movl $2048,%eax
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jmp LClampReentry4
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LClampHigh4:
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movl C(bbextents),%eax
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jmp LClampReentry4
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LClampLow5:
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movl $2048,%ebx
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jmp LClampReentry5
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LClampHigh5:
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movl C(bbextentt),%ebx
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jmp LClampReentry5
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#define pspans 4+16
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.align 4
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.globl C(D_SpriteDrawSpans)
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C(D_SpriteDrawSpans):
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pushl %ebp // preserve caller's stack frame
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pushl %edi
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pushl %esi // preserve register variables
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pushl %ebx
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//
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// set up scaled-by-8 steps, for 8-long segments; also set up cacheblock
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// and span list pointers, and 1/z step in 0.32 fixed-point
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//
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// FIXME: any overlap from rearranging?
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flds C(d_sdivzstepu)
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fmuls fp_8
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movl C(cacheblock),%edx
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flds C(d_tdivzstepu)
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fmuls fp_8
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movl pspans(%esp),%ebx // point to the first span descriptor
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flds C(d_zistepu)
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fmuls fp_8
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movl %edx,pbase // pbase = cacheblock
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flds C(d_zistepu)
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fmuls fp_64kx64k
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fxch %st(3)
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fstps sdivz8stepu
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fstps zi8stepu
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fstps tdivz8stepu
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fistpl izistep
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movl izistep,%eax
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rorl $16,%eax // put upper 16 bits in low word
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movl sspan_t_count(%ebx),%ecx
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movl %eax,izistep
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cmpl $0,%ecx
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jle LNextSpan
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LSpanLoop:
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//
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// set up the initial s/z, t/z, and 1/z on the FP stack, and generate the
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// initial s and t values
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//
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// FIXME: pipeline FILD?
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fildl sspan_t_v(%ebx)
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fildl sspan_t_u(%ebx)
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fld %st(1) // dv | du | dv
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fmuls C(d_sdivzstepv) // dv*d_sdivzstepv | du | dv
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fld %st(1) // du | dv*d_sdivzstepv | du | dv
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fmuls C(d_sdivzstepu) // du*d_sdivzstepu | dv*d_sdivzstepv | du | dv
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fld %st(2) // du | du*d_sdivzstepu | dv*d_sdivzstepv | du | dv
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fmuls C(d_tdivzstepu) // du*d_tdivzstepu | du*d_sdivzstepu |
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// dv*d_sdivzstepv | du | dv
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fxch %st(1) // du*d_sdivzstepu | du*d_tdivzstepu |
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// dv*d_sdivzstepv | du | dv
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faddp %st(0),%st(2) // du*d_tdivzstepu |
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// du*d_sdivzstepu + dv*d_sdivzstepv | du | dv
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fxch %st(1) // du*d_sdivzstepu + dv*d_sdivzstepv |
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// du*d_tdivzstepu | du | dv
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fld %st(3) // dv | du*d_sdivzstepu + dv*d_sdivzstepv |
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// du*d_tdivzstepu | du | dv
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fmuls C(d_tdivzstepv) // dv*d_tdivzstepv |
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// du*d_sdivzstepu + dv*d_sdivzstepv |
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// du*d_tdivzstepu | du | dv
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fxch %st(1) // du*d_sdivzstepu + dv*d_sdivzstepv |
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// dv*d_tdivzstepv | du*d_tdivzstepu | du | dv
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fadds C(d_sdivzorigin) // sdivz = d_sdivzorigin + dv*d_sdivzstepv +
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// du*d_sdivzstepu; stays in %st(2) at end
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fxch %st(4) // dv | dv*d_tdivzstepv | du*d_tdivzstepu | du |
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// s/z
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fmuls C(d_zistepv) // dv*d_zistepv | dv*d_tdivzstepv |
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// du*d_tdivzstepu | du | s/z
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fxch %st(1) // dv*d_tdivzstepv | dv*d_zistepv |
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// du*d_tdivzstepu | du | s/z
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faddp %st(0),%st(2) // dv*d_zistepv |
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// dv*d_tdivzstepv + du*d_tdivzstepu | du | s/z
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fxch %st(2) // du | dv*d_tdivzstepv + du*d_tdivzstepu |
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// dv*d_zistepv | s/z
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fmuls C(d_zistepu) // du*d_zistepu |
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// dv*d_tdivzstepv + du*d_tdivzstepu |
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// dv*d_zistepv | s/z
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fxch %st(1) // dv*d_tdivzstepv + du*d_tdivzstepu |
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// du*d_zistepu | dv*d_zistepv | s/z
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fadds C(d_tdivzorigin) // tdivz = d_tdivzorigin + dv*d_tdivzstepv +
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// du*d_tdivzstepu; stays in %st(1) at end
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fxch %st(2) // dv*d_zistepv | du*d_zistepu | t/z | s/z
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faddp %st(0),%st(1) // dv*d_zistepv + du*d_zistepu | t/z | s/z
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flds fp_64k // fp_64k | dv*d_zistepv + du*d_zistepu | t/z | s/z
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fxch %st(1) // dv*d_zistepv + du*d_zistepu | fp_64k | t/z | s/z
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fadds C(d_ziorigin) // zi = d_ziorigin + dv*d_zistepv +
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// du*d_zistepu; stays in %st(0) at end
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// 1/z | fp_64k | t/z | s/z
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fld %st(0) // FIXME: get rid of stall on FMUL?
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fmuls fp_64kx64k
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fxch %st(1)
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//
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// calculate and clamp s & t
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//
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fdivr %st(0),%st(2) // 1/z | z*64k | t/z | s/z
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fxch %st(1)
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fistpl izi // 0.32 fixed-point 1/z
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movl izi,%ebp
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//
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// set pz to point to the first z-buffer pixel in the span
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//
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rorl $16,%ebp // put upper 16 bits in low word
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movl sspan_t_v(%ebx),%eax
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movl %ebp,izi
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movl sspan_t_u(%ebx),%ebp
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imull C(d_zrowbytes)
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shll $1,%ebp // a word per pixel
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addl C(d_pzbuffer),%eax
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addl %ebp,%eax
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movl %eax,pz
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//
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// point %edi to the first pixel in the span
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//
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movl C(d_viewbuffer),%ebp
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movl sspan_t_v(%ebx),%eax
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pushl %ebx // preserve spans pointer
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movl C(tadjust),%edx
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movl C(sadjust),%esi
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movl C(d_scantable)(,%eax,4),%edi // v * screenwidth
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addl %ebp,%edi
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movl sspan_t_u(%ebx),%ebp
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addl %ebp,%edi // pdest = &pdestspan[scans->u];
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//
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// now start the FDIV for the end of the span
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//
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cmpl $8,%ecx
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ja LSetupNotLast1
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decl %ecx
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jz LCleanup1 // if only one pixel, no need to start an FDIV
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movl %ecx,spancountminus1
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// finish up the s and t calcs
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fxch %st(1) // z*64k | 1/z | t/z | s/z
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fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
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fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
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fxch %st(1) // z*64k | s | 1/z | t/z | s/z
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fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
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fxch %st(1) // s | t | 1/z | t/z | s/z
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fistpl s // 1/z | t | t/z | s/z
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fistpl t // 1/z | t/z | s/z
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fildl spancountminus1
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flds C(d_tdivzstepu) // _d_tdivzstepu | spancountminus1
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flds C(d_zistepu) // _d_zistepu | _d_tdivzstepu | spancountminus1
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fmul %st(2),%st(0) // _d_zistepu*scm1 | _d_tdivzstepu | scm1
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fxch %st(1) // _d_tdivzstepu | _d_zistepu*scm1 | scm1
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fmul %st(2),%st(0) // _d_tdivzstepu*scm1 | _d_zistepu*scm1 | scm1
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fxch %st(2) // scm1 | _d_zistepu*scm1 | _d_tdivzstepu*scm1
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fmuls C(d_sdivzstepu) // _d_sdivzstepu*scm1 | _d_zistepu*scm1 |
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// _d_tdivzstepu*scm1
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fxch %st(1) // _d_zistepu*scm1 | _d_sdivzstepu*scm1 |
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// _d_tdivzstepu*scm1
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faddp %st(0),%st(3) // _d_sdivzstepu*scm1 | _d_tdivzstepu*scm1
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fxch %st(1) // _d_tdivzstepu*scm1 | _d_sdivzstepu*scm1
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faddp %st(0),%st(3) // _d_sdivzstepu*scm1
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faddp %st(0),%st(3)
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flds fp_64k
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fdiv %st(1),%st(0) // this is what we've gone to all this trouble to
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// overlap
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jmp LFDIVInFlight1
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LCleanup1:
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// finish up the s and t calcs
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fxch %st(1) // z*64k | 1/z | t/z | s/z
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fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
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fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
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fxch %st(1) // z*64k | s | 1/z | t/z | s/z
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fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
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fxch %st(1) // s | t | 1/z | t/z | s/z
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fistpl s // 1/z | t | t/z | s/z
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fistpl t // 1/z | t/z | s/z
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jmp LFDIVInFlight1
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.align 4
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LSetupNotLast1:
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// finish up the s and t calcs
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fxch %st(1) // z*64k | 1/z | t/z | s/z
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fld %st(0) // z*64k | z*64k | 1/z | t/z | s/z
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fmul %st(4),%st(0) // s | z*64k | 1/z | t/z | s/z
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fxch %st(1) // z*64k | s | 1/z | t/z | s/z
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fmul %st(3),%st(0) // t | s | 1/z | t/z | s/z
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fxch %st(1) // s | t | 1/z | t/z | s/z
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fistpl s // 1/z | t | t/z | s/z
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fistpl t // 1/z | t/z | s/z
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fadds zi8stepu
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fxch %st(2)
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fadds sdivz8stepu
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fxch %st(2)
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flds tdivz8stepu
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faddp %st(0),%st(2)
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flds fp_64k
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fdiv %st(1),%st(0) // z = 1/1/z
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// this is what we've gone to all this trouble to
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// overlap
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LFDIVInFlight1:
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addl s,%esi
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addl t,%edx
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movl C(bbextents),%ebx
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movl C(bbextentt),%ebp
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cmpl %ebx,%esi
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ja LClampHighOrLow0
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LClampReentry0:
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movl %esi,s
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movl pbase,%ebx
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shll $16,%esi
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cmpl %ebp,%edx
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movl %esi,sfracf
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ja LClampHighOrLow1
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LClampReentry1:
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movl %edx,t
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movl s,%esi // sfrac = scans->sfrac;
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shll $16,%edx
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movl t,%eax // tfrac = scans->tfrac;
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sarl $16,%esi
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movl %edx,tfracf
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//
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// calculate the texture starting address
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//
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sarl $16,%eax
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addl %ebx,%esi
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imull C(cachewidth),%eax // (tfrac >> 16) * cachewidth
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addl %eax,%esi // psource = pbase + (sfrac >> 16) +
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// ((tfrac >> 16) * cachewidth);
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//
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// determine whether last span or not
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//
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cmpl $8,%ecx
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jna LLastSegment
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//
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// not the last segment; do full 8-wide segment
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//
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LNotLastSegment:
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//
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// advance s/z, t/z, and 1/z, and calculate s & t at end of span and steps to
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// get there
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//
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// pick up after the FDIV that was left in flight previously
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fld %st(0) // duplicate it
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fmul %st(4),%st(0) // s = s/z * z
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fxch %st(1)
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fmul %st(3),%st(0) // t = t/z * z
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fxch %st(1)
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fistpl snext
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fistpl tnext
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movl snext,%eax
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movl tnext,%edx
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subl $8,%ecx // count off this segments' pixels
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movl C(sadjust),%ebp
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pushl %ecx // remember count of remaining pixels
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movl C(tadjust),%ecx
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addl %eax,%ebp
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addl %edx,%ecx
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movl C(bbextents),%eax
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movl C(bbextentt),%edx
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cmpl $2048,%ebp
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jl LClampLow2
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cmpl %eax,%ebp
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ja LClampHigh2
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LClampReentry2:
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cmpl $2048,%ecx
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jl LClampLow3
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cmpl %edx,%ecx
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ja LClampHigh3
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LClampReentry3:
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movl %ebp,snext
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movl %ecx,tnext
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subl s,%ebp
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subl t,%ecx
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//
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// set up advancetable
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//
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movl %ecx,%eax
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movl %ebp,%edx
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sarl $19,%edx // sstep >>= 16;
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movl C(cachewidth),%ebx
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sarl $19,%eax // tstep >>= 16;
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jz LIsZero
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imull %ebx,%eax // (tstep >> 16) * cachewidth;
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LIsZero:
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addl %edx,%eax // add in sstep
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// (tstep >> 16) * cachewidth + (sstep >> 16);
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movl tfracf,%edx
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movl %eax,advancetable+4 // advance base in t
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addl %ebx,%eax // ((tstep >> 16) + 1) * cachewidth +
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// (sstep >> 16);
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shll $13,%ebp // left-justify sstep fractional part
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movl %ebp,sstep
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movl sfracf,%ebx
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shll $13,%ecx // left-justify tstep fractional part
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movl %eax,advancetable // advance extra in t
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movl %ecx,tstep
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movl pz,%ecx
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movl izi,%ebp
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cmpw (%ecx),%bp
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jl Lp1
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movb (%esi),%al // get first source texel
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cmpb $(TRANSPARENT_COLOR),%al
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jz Lp1
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movw %bp,(%ecx)
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movb %al,(%edi) // store first dest pixel
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Lp1:
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addl izistep,%ebp
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adcl $0,%ebp
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addl tstep,%edx // advance tfrac fractional part by tstep frac
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sbbl %eax,%eax // turn tstep carry into -1 (0 if none)
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addl sstep,%ebx // advance sfrac fractional part by sstep frac
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adcl advancetable+4(,%eax,4),%esi // point to next source texel
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cmpw 2(%ecx),%bp
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jl Lp2
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movb (%esi),%al
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cmpb $(TRANSPARENT_COLOR),%al
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jz Lp2
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movw %bp,2(%ecx)
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movb %al,1(%edi)
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Lp2:
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addl izistep,%ebp
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adcl $0,%ebp
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addl tstep,%edx
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sbbl %eax,%eax
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addl sstep,%ebx
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adcl advancetable+4(,%eax,4),%esi
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cmpw 4(%ecx),%bp
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jl Lp3
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movb (%esi),%al
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cmpb $(TRANSPARENT_COLOR),%al
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jz Lp3
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movw %bp,4(%ecx)
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movb %al,2(%edi)
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Lp3:
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addl izistep,%ebp
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adcl $0,%ebp
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addl tstep,%edx
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sbbl %eax,%eax
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addl sstep,%ebx
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adcl advancetable+4(,%eax,4),%esi
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cmpw 6(%ecx),%bp
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jl Lp4
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp4
|
|
movw %bp,6(%ecx)
|
|
movb %al,3(%edi)
|
|
Lp4:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
|
|
cmpw 8(%ecx),%bp
|
|
jl Lp5
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp5
|
|
movw %bp,8(%ecx)
|
|
movb %al,4(%edi)
|
|
Lp5:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
|
|
//
|
|
// start FDIV for end of next segment in flight, so it can overlap
|
|
//
|
|
popl %eax
|
|
cmpl $8,%eax // more than one segment after this?
|
|
ja LSetupNotLast2 // yes
|
|
|
|
decl %eax
|
|
jz LFDIVInFlight2 // if only one pixel, no need to start an FDIV
|
|
movl %eax,spancountminus1
|
|
fildl spancountminus1
|
|
|
|
flds C(d_zistepu) // _d_zistepu | spancountminus1
|
|
fmul %st(1),%st(0) // _d_zistepu*scm1 | scm1
|
|
flds C(d_tdivzstepu) // _d_tdivzstepu | _d_zistepu*scm1 | scm1
|
|
fmul %st(2),%st(0) // _d_tdivzstepu*scm1 | _d_zistepu*scm1 | scm1
|
|
fxch %st(1) // _d_zistepu*scm1 | _d_tdivzstepu*scm1 | scm1
|
|
faddp %st(0),%st(3) // _d_tdivzstepu*scm1 | scm1
|
|
fxch %st(1) // scm1 | _d_tdivzstepu*scm1
|
|
fmuls C(d_sdivzstepu) // _d_sdivzstepu*scm1 | _d_tdivzstepu*scm1
|
|
fxch %st(1) // _d_tdivzstepu*scm1 | _d_sdivzstepu*scm1
|
|
faddp %st(0),%st(3) // _d_sdivzstepu*scm1
|
|
flds fp_64k // 64k | _d_sdivzstepu*scm1
|
|
fxch %st(1) // _d_sdivzstepu*scm1 | 64k
|
|
faddp %st(0),%st(4) // 64k
|
|
|
|
fdiv %st(1),%st(0) // this is what we've gone to all this trouble to
|
|
// overlap
|
|
jmp LFDIVInFlight2
|
|
|
|
.align 4
|
|
LSetupNotLast2:
|
|
fadds zi8stepu
|
|
fxch %st(2)
|
|
fadds sdivz8stepu
|
|
fxch %st(2)
|
|
flds tdivz8stepu
|
|
faddp %st(0),%st(2)
|
|
flds fp_64k
|
|
fdiv %st(1),%st(0) // z = 1/1/z
|
|
// this is what we've gone to all this trouble to
|
|
// overlap
|
|
LFDIVInFlight2:
|
|
pushl %eax
|
|
|
|
cmpw 10(%ecx),%bp
|
|
jl Lp6
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp6
|
|
movw %bp,10(%ecx)
|
|
movb %al,5(%edi)
|
|
Lp6:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
|
|
cmpw 12(%ecx),%bp
|
|
jl Lp7
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp7
|
|
movw %bp,12(%ecx)
|
|
movb %al,6(%edi)
|
|
Lp7:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
|
|
cmpw 14(%ecx),%bp
|
|
jl Lp8
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp8
|
|
movw %bp,14(%ecx)
|
|
movb %al,7(%edi)
|
|
Lp8:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
|
|
addl $8,%edi
|
|
addl $16,%ecx
|
|
movl %edx,tfracf
|
|
movl snext,%edx
|
|
movl %ebx,sfracf
|
|
movl tnext,%ebx
|
|
movl %edx,s
|
|
movl %ebx,t
|
|
|
|
movl %ecx,pz
|
|
movl %ebp,izi
|
|
|
|
popl %ecx // retrieve count
|
|
|
|
//
|
|
// determine whether last span or not
|
|
//
|
|
cmpl $8,%ecx // are there multiple segments remaining?
|
|
ja LNotLastSegment // yes
|
|
|
|
//
|
|
// last segment of scan
|
|
//
|
|
LLastSegment:
|
|
|
|
//
|
|
// advance s/z, t/z, and 1/z, and calculate s & t at end of span and steps to
|
|
// get there. The number of pixels left is variable, and we want to land on the
|
|
// last pixel, not step one past it, so we can't run into arithmetic problems
|
|
//
|
|
testl %ecx,%ecx
|
|
jz LNoSteps // just draw the last pixel and we're done
|
|
|
|
// pick up after the FDIV that was left in flight previously
|
|
|
|
|
|
fld %st(0) // duplicate it
|
|
fmul %st(4),%st(0) // s = s/z * z
|
|
fxch %st(1)
|
|
fmul %st(3),%st(0) // t = t/z * z
|
|
fxch %st(1)
|
|
fistpl snext
|
|
fistpl tnext
|
|
|
|
movl C(tadjust),%ebx
|
|
movl C(sadjust),%eax
|
|
|
|
addl snext,%eax
|
|
addl tnext,%ebx
|
|
|
|
movl C(bbextents),%ebp
|
|
movl C(bbextentt),%edx
|
|
|
|
cmpl $2048,%eax
|
|
jl LClampLow4
|
|
cmpl %ebp,%eax
|
|
ja LClampHigh4
|
|
LClampReentry4:
|
|
movl %eax,snext
|
|
|
|
cmpl $2048,%ebx
|
|
jl LClampLow5
|
|
cmpl %edx,%ebx
|
|
ja LClampHigh5
|
|
LClampReentry5:
|
|
|
|
cmpl $1,%ecx // don't bother
|
|
je LOnlyOneStep // if two pixels in segment, there's only one step,
|
|
// of the segment length
|
|
subl s,%eax
|
|
subl t,%ebx
|
|
|
|
addl %eax,%eax // convert to 15.17 format so multiply by 1.31
|
|
addl %ebx,%ebx // reciprocal yields 16.48
|
|
imull reciprocal_table-8(,%ecx,4) // sstep = (snext - s) / (spancount-1)
|
|
movl %edx,%ebp
|
|
|
|
movl %ebx,%eax
|
|
imull reciprocal_table-8(,%ecx,4) // tstep = (tnext - t) / (spancount-1)
|
|
|
|
LSetEntryvec:
|
|
//
|
|
// set up advancetable
|
|
//
|
|
movl spr8entryvec_table(,%ecx,4),%ebx
|
|
movl %edx,%eax
|
|
pushl %ebx // entry point into code for RET later
|
|
movl %ebp,%ecx
|
|
sarl $16,%ecx // sstep >>= 16;
|
|
movl C(cachewidth),%ebx
|
|
sarl $16,%edx // tstep >>= 16;
|
|
jz LIsZeroLast
|
|
imull %ebx,%edx // (tstep >> 16) * cachewidth;
|
|
LIsZeroLast:
|
|
addl %ecx,%edx // add in sstep
|
|
// (tstep >> 16) * cachewidth + (sstep >> 16);
|
|
movl tfracf,%ecx
|
|
movl %edx,advancetable+4 // advance base in t
|
|
addl %ebx,%edx // ((tstep >> 16) + 1) * cachewidth +
|
|
// (sstep >> 16);
|
|
shll $16,%ebp // left-justify sstep fractional part
|
|
movl sfracf,%ebx
|
|
shll $16,%eax // left-justify tstep fractional part
|
|
movl %edx,advancetable // advance extra in t
|
|
|
|
movl %eax,tstep
|
|
movl %ebp,sstep
|
|
movl %ecx,%edx
|
|
|
|
movl pz,%ecx
|
|
movl izi,%ebp
|
|
|
|
ret // jump to the number-of-pixels handler
|
|
|
|
//----------------------------------------
|
|
|
|
LNoSteps:
|
|
movl pz,%ecx
|
|
subl $7,%edi // adjust for hardwired offset
|
|
subl $14,%ecx
|
|
jmp LEndSpan
|
|
|
|
|
|
LOnlyOneStep:
|
|
subl s,%eax
|
|
subl t,%ebx
|
|
movl %eax,%ebp
|
|
movl %ebx,%edx
|
|
jmp LSetEntryvec
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Spr8Entry2_8
|
|
Spr8Entry2_8:
|
|
subl $6,%edi // adjust for hardwired offsets
|
|
subl $12,%ecx
|
|
movb (%esi),%al
|
|
jmp LLEntry2_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Spr8Entry3_8
|
|
Spr8Entry3_8:
|
|
subl $5,%edi // adjust for hardwired offsets
|
|
subl $10,%ecx
|
|
jmp LLEntry3_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Spr8Entry4_8
|
|
Spr8Entry4_8:
|
|
subl $4,%edi // adjust for hardwired offsets
|
|
subl $8,%ecx
|
|
jmp LLEntry4_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Spr8Entry5_8
|
|
Spr8Entry5_8:
|
|
subl $3,%edi // adjust for hardwired offsets
|
|
subl $6,%ecx
|
|
jmp LLEntry5_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Spr8Entry6_8
|
|
Spr8Entry6_8:
|
|
subl $2,%edi // adjust for hardwired offsets
|
|
subl $4,%ecx
|
|
jmp LLEntry6_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Spr8Entry7_8
|
|
Spr8Entry7_8:
|
|
decl %edi // adjust for hardwired offsets
|
|
subl $2,%ecx
|
|
jmp LLEntry7_8
|
|
|
|
//----------------------------------------
|
|
|
|
.globl Spr8Entry8_8
|
|
Spr8Entry8_8:
|
|
cmpw (%ecx),%bp
|
|
jl Lp9
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp9
|
|
movw %bp,(%ecx)
|
|
movb %al,(%edi)
|
|
Lp9:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
LLEntry7_8:
|
|
cmpw 2(%ecx),%bp
|
|
jl Lp10
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp10
|
|
movw %bp,2(%ecx)
|
|
movb %al,1(%edi)
|
|
Lp10:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
LLEntry6_8:
|
|
cmpw 4(%ecx),%bp
|
|
jl Lp11
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp11
|
|
movw %bp,4(%ecx)
|
|
movb %al,2(%edi)
|
|
Lp11:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
LLEntry5_8:
|
|
cmpw 6(%ecx),%bp
|
|
jl Lp12
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp12
|
|
movw %bp,6(%ecx)
|
|
movb %al,3(%edi)
|
|
Lp12:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
LLEntry4_8:
|
|
cmpw 8(%ecx),%bp
|
|
jl Lp13
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp13
|
|
movw %bp,8(%ecx)
|
|
movb %al,4(%edi)
|
|
Lp13:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
LLEntry3_8:
|
|
cmpw 10(%ecx),%bp
|
|
jl Lp14
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp14
|
|
movw %bp,10(%ecx)
|
|
movb %al,5(%edi)
|
|
Lp14:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
LLEntry2_8:
|
|
cmpw 12(%ecx),%bp
|
|
jl Lp15
|
|
movb (%esi),%al
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp15
|
|
movw %bp,12(%ecx)
|
|
movb %al,6(%edi)
|
|
Lp15:
|
|
addl izistep,%ebp
|
|
adcl $0,%ebp
|
|
addl tstep,%edx
|
|
sbbl %eax,%eax
|
|
addl sstep,%ebx
|
|
adcl advancetable+4(,%eax,4),%esi
|
|
|
|
LEndSpan:
|
|
cmpw 14(%ecx),%bp
|
|
jl Lp16
|
|
movb (%esi),%al // load first texel in segment
|
|
cmpb $(TRANSPARENT_COLOR),%al
|
|
jz Lp16
|
|
movw %bp,14(%ecx)
|
|
movb %al,7(%edi)
|
|
Lp16:
|
|
|
|
//
|
|
// clear s/z, t/z, 1/z from FP stack
|
|
//
|
|
fstp %st(0)
|
|
fstp %st(0)
|
|
fstp %st(0)
|
|
|
|
popl %ebx // restore spans pointer
|
|
LNextSpan:
|
|
addl $(sspan_t_size),%ebx // point to next span
|
|
movl sspan_t_count(%ebx),%ecx
|
|
cmpl $0,%ecx // any more spans?
|
|
jg LSpanLoop // yes
|
|
jz LNextSpan // yes, but this one's empty
|
|
|
|
popl %ebx // restore register variables
|
|
popl %esi
|
|
popl %edi
|
|
popl %ebp // restore the caller's stack frame
|
|
ret
|
|
|
|
#endif // id386
|