X-Git-Url: http://4ch.mooo.com/gitweb/?a=blobdiff_plain;f=16%2Fxw%2Fmxcc.asm;fp=16%2Fxw%2Fmxcc.asm;h=4f78adb9c6801bf68a9984b08ad2f0902e941472;hb=47cdc66151d973d975d0e31fb8a786eb639bebdb;hp=0000000000000000000000000000000000000000;hpb=4b23f27092a9470a741e3a18261ad389fd1929db;p=16.git diff --git a/16/xw/mxcc.asm b/16/xw/mxcc.asm new file mode 100755 index 00000000..4f78adb9 --- /dev/null +++ b/16/xw/mxcc.asm @@ -0,0 +1,644 @@ +;----------------------------------------------------------- +; +; MXCC.ASM - Fast clip line function +; Copyright (c) 1994 by Alessandro Scotti +; +;----------------------------------------------------------- +WARN PRO +NOWARN RES +INCLUDE MODEX.DEF + +PUBLIC xsubClipLine + +MX_TEXT SEGMENT USE16 PARA PUBLIC 'CODE' + ASSUME cs:MX_TEXT, ds:NOTHING, es:NOTHING + +EXTRN mx_BytesPerLine : WORD +EXTRN mx_VideoSegment : WORD + +EXTRN mx_ClipX1 : WORD +EXTRN mx_ClipY1 : WORD +EXTRN mx_ClipX2 : WORD +EXTRN mx_ClipY2 : WORD + +tblGroups LABEL WORD + DW 10, tbl00 + DW 10, tbl10 + DW 9, tbl20 + DW -1, 0 + DW 10, tbl40 + DW 10, tbl50 + DW 9, tbl60 + DW -1, 0 + DW 6, tbl80 + DW 6, tbl90 + DW 5, tblA0 + DW -1, 0 + DW -1, 0 + DW -1, 0 + DW -1, 0 + DW -1, 0 +tbl00 DW cc00, cc01, cc02, ccFF, cc04, cc05, cc06, ccFF, cc08, cc09, cc0A +tbl10 DW cc10, ccFF, cc12, ccFF, cc14, ccFF, cc16, ccFF, cc18, ccFF, cc1A +tbl20 DW cc20, cc21, ccFF, ccFF, cc24, cc25, ccFF, ccFF, cc28, cc29 +tbl40 DW cc40, cc41, cc42, ccFF, ccFF, ccFF, ccFF, ccFF, cc48, cc49, cc4A +tbl50 DW cc50, ccFF, cc52, ccFF, ccFF, ccFF, ccFF, ccFF, cc58, ccFF, cc5A +tbl60 DW cc60, cc61, ccFF, ccFF, ccFF, ccFF, ccFF, ccFF, cc68, cc69 +tbl80 DW cc80, cc81, cc82, ccFF, cc84, cc85, cc86 +tbl90 DW cc90, ccFF, cc92, ccFF, cc94, ccFF, cc96 +tblA0 DW ccA0, ccA1, ccFF, ccFF, ccA4, ccA5 + +ccTT: clc + ret +ccFF: stc + ret + +; Group 00 ------------------------------------------------- +; +cc00: + clc + ret +cc01: + jmp ClipQLeft +cc02: + jmp ClipQRight +cc04: + jmp ClipQTop +cc05: + call ClipQLeft + cmp si, [mx_ClipY1] + jge ccTT + jmp ClipQTop +cc06: + call ClipQRight + cmp si, [mx_ClipY1] + jge ccTT + jmp ClipQTop +cc08: + jmp ClipQBottom +cc09: + call ClipQLeft + cmp si, [mx_ClipY2] + jle ccTT + jmp ClipQBottom +cc0A: + call ClipQRight + cmp si, [mx_ClipY2] + jle ccTT + jmp ClipQBottom + +; Group 10 ------------------------------------------------- +; +cc10FF: + stc + ret +cc10TT: + clc + ret +cc10: + jmp ClipPLeft +cc12: + call ClipPLeft + jmp ClipQRight +cc14: + call ClipPLeft + cmp bx, [mx_ClipY1] + jl cc10FF + jmp ClipQTop +cc16: + call ClipPLeft + cmp bx, [mx_ClipY1] + jl cc10FF + call ClipQTop + cmp cx, [mx_ClipX2] + jle cc10TT + jmp ClipQRight +cc18: + call ClipPLeft + cmp bx, [mx_ClipY2] + jg cc10FF + jmp ClipQBottom +cc1A: + call ClipPLeft + cmp bx, [mx_ClipY2] + jg cc10FF + call ClipQBottom + cmp cx, [mx_ClipX2] + jle cc10TT + jmp ClipQRight + +; Group 20 ------------------------------------------------- +; +cc20TT: + clc + ret +cc20FF: + stc + ret +cc20: + jmp ClipPRight +cc21: + call ClipPRight + jmp ClipQLeft +cc24: + call ClipPRight + cmp bx, [mx_ClipY1] + jl cc20FF + jmp ClipQTop +cc25: + call ClipPRight + cmp bx, [mx_ClipY1] + jl cc20FF + call ClipQTop + cmp cx, [mx_ClipX1] + jge cc20TT + jmp ClipQLeft +cc28: + call ClipPRight + cmp bx, [mx_ClipY2] + jg cc20FF + jmp ClipQBottom +cc29: + call ClipPRight + cmp bx, [mx_ClipY2] + jg cc20FF + call ClipQBottom + cmp cx, [mx_ClipX1] + jge cc20TT + jmp ClipQLeft + +; Group 40 ------------------------------------------------- +; +cc40TT: + clc + ret +cc40FF: + stc + ret +cc40: + jmp ClipPTop +cc41: + call ClipPTop + cmp di, [mx_ClipX1] + jl cc40FF + call ClipQLeft + cmp si, [mx_ClipY1] + jge cc40TT + jmp ClipQTop +cc42: + call ClipPTop + cmp di, [mx_ClipX2] + jg cc40FF + jmp ClipQRight +cc48: + call ClipPTop + jmp ClipQBottom +cc49: + call ClipPTop + cmp di, [mx_ClipX1] + jl cc40FF + call ClipQLeft + cmp si, [mx_ClipY2] + jle cc40TT + jmp ClipQBottom +cc4A: + call ClipPTop + cmp di, [mx_ClipX2] + jg cc40FF + call ClipQRight + cmp si, [mx_ClipY2] + jle cc40TT + jmp ClipQBottom + + +; Group 50 ------------------------------------------------- +; +cc50TT: + clc + ret +cc50FF: + stc + ret +cc50: + call ClipPLeft + cmp bx, [mx_ClipY1] + jge cc50TT + jmp ClipPTop +cc52: + call ClipQRight + cmp si, [mx_ClipY1] + jl cc50FF + call ClipPTop + cmp di, [mx_ClipX1] + jge cc50TT + jmp ClipPLeft +cc58: + call ClipQBottom + cmp cx, [mx_ClipX1] + jl cc50FF + call ClipPTop + cmp di, [mx_ClipX1] + jge cc50TT + jmp ClipPLeft +cc5A: + call ClipPLeft + cmp bx, [mx_ClipY2] + jg cc50FF + call ClipQRight + cmp bx, [mx_ClipY1] + jl cc50FF + cmp si, [mx_ClipY2] + jle cc50TT + jmp ClipQBottom + +; Group 60 ------------------------------------------------- +; +cc60TT: + clc + ret +cc60FF: + stc + ret +cc60: + call ClipPRight + cmp bx, [mx_ClipY1] + jge cc60TT + jmp ClipPTop +cc61: + call ClipQLeft + cmp si, [mx_ClipY2] + jl cc60FF + call ClipPTop + cmp di, [mx_ClipX2] + jle cc60TT + jmp ClipPRight +cc68: + call ClipQBottom + cmp cx, [mx_ClipX2] + jg cc60FF + call ClipPRight + cmp bx, [mx_ClipY1] + jge cc60TT + jmp ClipPTop +cc69: + call ClipQLeft + cmp si, [mx_ClipY1] + jl cc60FF + call ClipPRight + cmp bx, [mx_ClipY2] + jg cc60FF + cmp si, [mx_ClipY2] + jle cc69_1 + call ClipQBottom +cc69_1: + cmp bx, [mx_ClipY1] + jge cc60TT + jmp ClipPTop + +; Group 80 ------------------------------------------------- +; +cc80TT: + clc + ret +cc80FF: + stc + ret +cc80: + jmp ClipPBottom +cc81: + call ClipPBottom + cmp di, [mx_ClipX1] + jl cc80FF + jmp ClipQLeft +cc82: + call ClipPBottom + cmp di, [mx_ClipX2] + jg cc80FF + jmp ClipQRight +cc84: + call ClipPBottom + jmp ClipQTop +cc85: + call ClipPBottom + cmp di, [mx_ClipX1] + jl cc80FF + call ClipQLeft + cmp si, [mx_ClipY1] + jge cc80FF + jmp ClipQTop +cc86: + call ClipPBottom + cmp di, [mx_ClipX2] + jg cc80FF + call ClipQRight + cmp si, [mx_ClipY1] + jge cc80TT + jmp ClipQTop + +; Group 90 ------------------------------------------------- +; +cc90TT: + clc + ret +cc90FF: + stc + ret +cc90: + call ClipPLeft + cmp bx, [mx_ClipY2] + jle cc90TT + jmp ClipPBottom +cc92: + call ClipQRight + cmp si, [mx_ClipY2] + jg cc90FF + call ClipPBottom + cmp di, [mx_ClipX1] + jge cc90TT + jmp ClipPLeft +cc94: + call ClipQTop + cmp cx, [mx_ClipX1] + jl cc90FF + call ClipPLeft + cmp bx, [mx_ClipY2] + jle cc90TT + jmp ClipPBottom +cc96: + call ClipPLeft + cmp bx, [mx_ClipY1] + jl cc90FF + call ClipQRight + cmp si, [mx_ClipY2] + jg cc90FF + cmp bx, [mx_ClipY2] + jle cc96_1 + call ClipPBottom +cc96_1: + cmp si, [mx_ClipY1] + jge cc90TT + jmp ClipQTop + +; Group A0 ------------------------------------------------- +; +ccA0TT: + clc + ret +ccA0FF: + stc + ret +ccA0: + call ClipPRight + cmp bx, [mx_ClipY2] + jle ccA0TT + jmp ClipPBottom +ccA1: + call ClipQLeft + cmp si, [mx_ClipY2] + jg ccA0FF + call ClipPBottom + cmp di, [mx_ClipX2] + jle ccA0TT + jmp ClipPRight +ccA4: + call ClipQTop + cmp cx, [mx_ClipX2] + jg ccA0FF + call ClipPRight + cmp bx, [mx_ClipY2] + jle ccA0TT + jmp ClipPBottom +ccA5: + call ClipQLeft + cmp si, [mx_ClipY2] + jg ccA0FF + call ClipPRight + cmp bx, [mx_ClipY1] + jl ccA0FF + cmp si, [mx_ClipY1] + jge ccA5_1 + call ClipQTop +ccA5_1: + cmp bx, [mx_ClipY2] + jle ccA0TT + jmp ClipPBottom + +; Y1 = (Y2-Y1)*(mx_ClipX1-X1)/(X2-X1)+Y1 = (SI-BX)*(mx_ClipX1-DI)/(CX-DI)+BX +; X1 = mx_ClipX1 +ClipPLeft: + mov ax, si + sub ax, bx + mov dx, [mx_ClipX1] + sub dx, di + imul dx + mov bp, cx + sub bp, di + idiv bp + add bx, ax + mov di, [mx_ClipX1] + clc + ret + +; Y1 = (Y2-Y1)*(mx_ClipX2-X1)/(X2-X1)+Y1 = (SI-BX)*(mx_ClipX2-DI)/(CX-DI)+BX +; X1 = mx_ClipX2 +ClipPRight: + mov ax, si + sub ax, bx + mov dx, [mx_ClipX2] + sub dx, di + imul dx + mov bp, cx + sub bp, di + idiv bp + add bx, ax + mov di, [mx_ClipX2] + clc + ret + +; X1 = (X2-X1)*(mx_ClipY2-Y1)/(Y2-Y1)+X1 = (CX-DI)*(mx_ClipY2-BX)/(SI-BX)+DI +; Y1 = mx_ClipY2 +ClipPBottom: + mov ax, cx + sub ax, di + mov dx, [mx_ClipY2] + sub dx, bx + imul dx + mov bp, si + sub bp, bx + idiv bp + add di, ax + mov bx, [mx_ClipY2] + clc + ret + +; X1 = (X2-X1)*(mx_ClipY1-Y1)/(Y2-Y1)+X1 = (CX-DI)*(mx_ClipY1-BX)/(SI-BX)+DI +; Y1 = mx_ClipY1 +ClipPTop: + mov ax, cx + sub ax, di + mov dx, [mx_ClipY1] + sub dx, bx + imul dx + mov bp, si + sub bp, bx + idiv bp + add di, ax + mov bx, [mx_ClipY1] + clc + ret + +; Y2 = (Y1-Y2)*(mx_ClipX1-X2)/(X1-X2)+Y2 = (BX-SI)*(mx_ClipX1-CX)/(DI-CX)+SI +; X2 = mx_ClipX1 +ClipQLeft: + mov ax, bx + sub ax, si + mov dx, [mx_ClipX1] + sub dx, cx + imul dx + mov bp, di + sub bp, cx + idiv bp + add si, ax + mov cx, [mx_ClipX1] + clc + ret + +; Y2 = (Y1-Y2)*(mx_ClipX2-X2)/(X1-X2)+Y2 = (BX-SI)*(mx_ClipX2-CX)/(DI-CX)+SI +; X2 = mx_ClipX1 +ClipQRight: + mov ax, bx + sub ax, si + mov dx, [mx_ClipX2] + sub dx, cx + imul dx + mov bp, di + sub bp, cx + idiv bp + add si, ax + mov cx, [mx_ClipX2] + clc + ret + +; X2 = (X1-X2)*(mx_ClipY2-Y2)/(Y1-Y2)+X2 = (DI-CX)*(mx_ClipY2-SI)/(BX-SI)+CX +; Y2 = mx_ClipY1 +ClipQBottom: + mov ax, di + sub ax, cx + mov dx, [mx_ClipY2] + sub dx, si + imul dx + mov bp, bx + sub bp, si + idiv bp + add cx, ax + mov si, [mx_ClipY2] + clc + ret + +; X2 = (X1-X2)*(mx_ClipY1-Y2)/(Y1-Y2)+X2 = (DI-CX)*(mx_ClipY1-SI)/(BX-SI)+CX +; Y2 = mx_ClipY1 +ClipQTop: + mov ax, di + sub ax, cx + mov dx, [mx_ClipY1] + sub dx, si + imul dx + mov bp, bx + sub bp, si + idiv bp + add cx, ax + mov si, [mx_ClipY1] + clc + ret + +;----------------------------------------------------------- +; +; Checks the coordinates of a line against the active +; clip region. +; Uses the Sobkow-Pospisil-Yang (SPY) algorithm: this was +; supposed to be twice as fast as Cohen-Sutherland, but my +; tests show only a very small increase in speed and a noticeable +; increase of the program size! Maybe this is caused by the +; slow speed of VGA cards, so probably a better test should +; be performed with lines drawn in RAM. +; +; Input: +; AX, BX = X1, Y1 +; CX, DX = X2, Y2 +; Output: +; CF = set if line is full clipped +; AX, BX = clipped X1, Y1 +; CX, DX = clipped X2, Y2 +; Note: +; destroys SI, DI +; +xsubClipLine PROC NEAR + push bp + xor si, si ; SPY code + + cmp dx, [mx_ClipY2] + jle @@1 + or si, 08h + jmp @@2 +@@1: + cmp dx, [mx_ClipY1] + jge @@2 + or si, 04h +@@2: + + cmp cx, [mx_ClipX2] + jle @@3 + or si, 02h + jmp @@4 +@@3: + cmp cx, [mx_ClipX1] + jge @@4 + or si, 01h +@@4: + + cmp bx, [mx_ClipY2] + jle @@5 + or si, 80h + jmp @@6 +@@5: + cmp bx, [mx_ClipY1] + jge @@6 + or si, 40h +@@6: + + cmp ax, [mx_ClipX2] + jle @@7 + or si, 20h + jmp @@8 +@@7: + cmp ax, [mx_ClipX1] + jge @@8 + or si, 10h +@@8: + + mov di, si + and di, 000Fh ; Index of procedure + and si, 00F0h + .shr si, 2 ; Index of group (times 4) + cmp di, cs:tblGroups[si] ; Is index within range? + jg @@Exit ; No, line is full clipped + mov si, cs:tblGroups[si+2] ; Get offset of group table + shl di, 1 ; We must index word elements + add si, di ; Make full offset + mov di, ax ; Move X1 to DI and free AX + mov si, cs:[si] ; Get subroutine address + xchg dx, si ; Move Y2 to SI and free DX + call dx ; Call the proper subroutine + mov ax, di ; Restore AX to X1 + mov dx, si ; Restore DX to Y2 + pop bp + ret + +@@Exit: + pop bp + stc + ret +xsubClipLine ENDP + +MX_TEXT ENDS +END