*=======================================================* * Display-engine module: latest update 27/11/95 * *=======================================================* * Call all display modules in correct order * *=======================================================* * > New 68030 module by Douglas Little. * *=======================================================* lighting_effects ; enable for light & shadows *-------------------------------------------------------* display_engine: *-------------------------------------------------------* * Calculate window base-address (centering) * *-------------------------------------------------------* move.l ScreenLog,d0 move.w scrwidth,d1 sub.w width,d1 lsr.w d1 ext.l d1 add.l d1,d1 add.l d1,d0 move.l d0,screen *-------------------------------------------------------* * Reset wall & floor buffers for this frame * *-------------------------------------------------------* bsr init_wall_lists bsr init_floor_lists *-------------------------------------------------------* ifd dsp *-------------------------------------------------------* dspwrite.l #clear_command *-------------------------------------------------------* endc *-------------------------------------------------------* * Init display variables for this frame * *-------------------------------------------------------* bsr update_display_struct *-------------------------------------------------------* * Init lighting effects for this frame * *-------------------------------------------------------* bsr set_lighting *-------------------------------------------------------* * Clearscreen for resizing window & debugging * *-------------------------------------------------------* ; move.b #1,refresh move.l ScreenLog,a0 bsr clearscreen *-------------------------------------------------------* * Descend BSP tree & build scenery * *-------------------------------------------------------* bsr descend_bsp *-------------------------------------------------------* * Render floors & ceilings onto framebuffer * *-------------------------------------------------------* bsr render_flats *-------------------------------------------------------* * Render walls onto framebuffer * *-------------------------------------------------------* bsr render_walls *-------------------------------------------------------* rts *-------------------------------------------------------* * Init wall edgebuffer lists * *-------------------------------------------------------* init_wall_lists: *-------------------------------------------------------* lea maxy,a0 lea miny,a1 lea occlusion_list,a2 move.w height,d1 moveq #0,d2 moveq #-1,d3 move.w width,d0 subq.w #1,d0 .for_i: move.w d1,(a0)+ move.w d2,(a1)+ move.b d3,(a2)+ dbra d0,.for_i clr.w wallruncount move.w width,columns rts *-------------------------------------------------------* * Init floor edgebuffer lists * *-------------------------------------------------------* init_floor_lists: *-------------------------------------------------------* lea flatruncounts,a0 moveq #0,d1 move.w height,d0 subq.w #1,d0 .clr: move.w d1,(a0)+ dbra d0,.clr rts *-------------------------------------------------------* * Set up general (engine) structures & tables * *-------------------------------------------------------* init_engine: *-------------------------------------------------------* lea display_struct,a6 *-------------------------------------------------------* * Initialise pointers to WAD room data * *-------------------------------------------------------* move.l PNode_Array,display_nodes(a6) move.l Seg_Array,display_segs(a6) move.l Sector_Array,display_sectors(a6) move.l SSector_Array,display_ssectors(a6) move.l Side_Array,display_sidedefs(a6) move.l Line_Array,display_linedefs(a6) move.l Vertex_Array,display_vertices(a6) *-------------------------------------------------------* * Create transparent (glass) translation table * *-------------------------------------------------------* bsr init_glass rts *-------------------------------------------------------* * Update general (engine) display structure * *-------------------------------------------------------* update_display_struct: *-------------------------------------------------------* lea display_struct,a6 *-------------------------------------------------------* * Set up player position and angle * *-------------------------------------------------------* move.l SinPangle,d3 move.l CosPangle,d4 asr.l #2,d3 asr.l #2,d4 move.w d3,display_sina(a6) move.w d4,display_cosa(a6) move.w Px,display_px(a6) move.w Py,display_py(a6) *-------------------------------------------------------* * Calculate base address of octant routine * *-------------------------------------------------------* move.w Pangle,d7 moveq #(16-3),d0 lsr.w d0,d7 lea octs,a0 move.w (a0,d7.w*2),display_octant(a6) *-------------------------------------------------------* move.w #1,first_ssector *-------------------------------------------------------* rts *-------------------------------------------------------* * Select new display window size * *-------------------------------------------------------* select_window: *-------------------------------------------------------* pushall moveq #10,d1 move.w window_size,d2 cmp.w #256,d2 bpl.s .ok1 move.w #256,d2 .ok1 cmp.w #1<<10,d2 bmi.s .ok2 move.w #1<<10,d2 .ok2: move.w d2,window_size *-------------------------------------------------------* move.w d2,d0 mulu.w #max_width,d0 lsr.l d1,d0 move.w d0,width *-------------------------------------------------------* move.w d2,d0 mulu.w #max_height,d0 lsr.l d1,d0 move.w d0,height *-------------------------------------------------------* * Update global display structure * *-------------------------------------------------------* lea display_struct,a6 move.w width,d1 move.w d1,display_width(a6) lsr.w d1 move.w d1,display_shwid(a6) *-------------------------------------------------------* * Update addwall structure * *-------------------------------------------------------* lea addwall_struct,a6 move.w width,addwall_xsize(a6) move.w height,addwall_ysize(a6) *-------------------------------------------------------* * 3 CLS calls required to wipe log, phys & bak * *-------------------------------------------------------* move.b #3,refresh *-------------------------------------------------------* * Recalculate video display height * *-------------------------------------------------------* move.b #1,adjust *-------------------------------------------------------* * Resize DSP rendering zone * *-------------------------------------------------------* ifd dsp *-------------------------------------------------------* dspwrite.l #resize_command moveq #0,d0 move.w width,d0 dspwrite.l d0 move.w height,d0 dspwrite.l d0 *-------------------------------------------------------* endc *-------------------------------------------------------* popall rts *-------------------------------------------------------* clearscreen: *-------------------------------------------------------* tst.b refresh bne.s .go rts .go: subq.b #1,refresh move.w #(320*200)/2,d0 *-------------------------------------------------------* clearlongs: *-------------------------------------------------------* moveq #0,d1 move.l d1,d2 move.l d2,d3 move.l d2,d4 move.l d2,d5 move.l d2,d6 move.l d2,d7 move.l d2,a2 move.l d2,a3 moveq #128-1,d1 and.l d0,d1 bra.s .strt .long move.l d2,(a0)+ .strt dbra d1,.long lsr.l #7,d0 move.l d0,d1 lsl.l #8,d1 ; *256 lsl.l #1,d1 ; *2 = *512 add.l d1,a0 bra.s .next .clr movem.l d2-d7/a2-a3,-(a0) ; 4*8*16 = 512 movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) movem.l d2-d7/a2-a3,-(a0) .next dbra d0,.clr rts *-------------------------------------------------------* * Doom engine subroutines * *-------------------------------------------------------* *-------------------------------------------------------* ifd dsp *-------------------------------------------------------* include dspwalls.s *-------------------------------------------------------* elseif *-------------------------------------------------------* include addwall.s *-------------------------------------------------------* endc *-------------------------------------------------------* include bspd.s include render.s include lighting.s include timing.s include tables.s *-------------------------------------------------------* bss *-------------------------------------------------------* window_size: ds.w 1 width: ds.w 1 height: ds.w 1 display_struct: ds.b display_len 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