+++ /dev/null
-\r
-// This file is part of the PicoDrive Megadrive Emulator\r
-\r
-// Copyright (c) 2011 FinalDave (emudave (at) gmail.com)\r
-\r
-// This code is licensed under the GNU General Public License version 2.0 and the MAME License.\r
-// You can choose the license that has the most advantages for you.\r
-\r
-// SVN repository can be found at http://code.google.com/p/cyclone68000/\r
-\r
-#include "PicoInt.h"\r
-#ifndef __GNUC__\r
-#pragma warning (disable:4706) // Disable assignment with conditional\r
-#endif\r
-\r
-int (*PicoScan)(unsigned int num,unsigned short *data)=NULL;\r
-\r
-// Line colour indices - in the format 00ppcccc pp=palette, cccc=colour\r
-static unsigned short HighCol[32+320+8]; // Gap for 32 column, and messy border on right\r
-static int Scanline=0; // Scanline\r
-\r
-int PicoMask=0xfff; // Mask of which layers to draw\r
-\r
-static int TileNorm(unsigned short *pd,int addr,unsigned int *pal)\r
-{\r
- unsigned int pack=0; unsigned int t=0;\r
-\r
- pack=*(unsigned int *)(Pico.vram+addr); // Get 8 pixels\r
- if (pack)\r
- {\r
- t=pack&0x0000f000; if (t) { t=pal[t>>12]; pd[0]=(unsigned short)t; }\r
- t=pack&0x00000f00; if (t) { t=pal[t>> 8]; pd[1]=(unsigned short)t; }\r
- t=pack&0x000000f0; if (t) { t=pal[t>> 4]; pd[2]=(unsigned short)t; }\r
- t=pack&0x0000000f; if (t) { t=pal[t ]; pd[3]=(unsigned short)t; }\r
- t=pack&0xf0000000; if (t) { t=pal[t>>28]; pd[4]=(unsigned short)t; }\r
- t=pack&0x0f000000; if (t) { t=pal[t>>24]; pd[5]=(unsigned short)t; }\r
- t=pack&0x00f00000; if (t) { t=pal[t>>20]; pd[6]=(unsigned short)t; }\r
- t=pack&0x000f0000; if (t) { t=pal[t>>16]; pd[7]=(unsigned short)t; }\r
- return 0;\r
- }\r
-\r
- return 1; // Tile blank\r
-}\r
-\r
-static int TileFlip(unsigned short *pd,int addr,unsigned int *pal)\r
-{\r
- unsigned int pack=0; unsigned int t=0;\r
-\r
- pack=*(unsigned int *)(Pico.vram+addr); // Get 8 pixels\r
- if (pack)\r
- {\r
- t=pack&0x000f0000; if (t) { t=pal[t>>16]; pd[0]=(unsigned short)t; }\r
- t=pack&0x00f00000; if (t) { t=pal[t>>20]; pd[1]=(unsigned short)t; }\r
- t=pack&0x0f000000; if (t) { t=pal[t>>24]; pd[2]=(unsigned short)t; }\r
- t=pack&0xf0000000; if (t) { t=pal[t>>28]; pd[3]=(unsigned short)t; }\r
- t=pack&0x0000000f; if (t) { t=pal[t ]; pd[4]=(unsigned short)t; }\r
- t=pack&0x000000f0; if (t) { t=pal[t>> 4]; pd[5]=(unsigned short)t; }\r
- t=pack&0x00000f00; if (t) { t=pal[t>> 8]; pd[6]=(unsigned short)t; }\r
- t=pack&0x0000f000; if (t) { t=pal[t>>12]; pd[7]=(unsigned short)t; }\r
- return 0;\r
- }\r
- return 1; // Tile blank\r
-}\r
-\r
-struct TileStrip\r
-{\r
- int nametab; // Position in VRAM of name table (for this tile line)\r
- int line; // Line number in pixels 0x000-0x3ff within the virtual tilemap \r
- int hscroll; // Horizontal scroll value in pixels for the line\r
- int xmask; // X-Mask (0x1f - 0x7f) for horizontal wraparound in the tilemap\r
- int high; // High or low tiles\r
-};\r
-\r
-static int WrongPri=0; // 1 if there were tiles which are the wrong priority\r
-\r
-static int DrawStrip(struct TileStrip ts)\r
-{\r
- int tilex=0,dx=0,ty=0;\r
- int blank=-1; // The tile we know is blank\r
-\r
- WrongPri=0;\r
-\r
- // Draw tiles across screen:\r
- tilex=(-ts.hscroll)>>3;\r
- ty=(ts.line&7)<<1; // Y-Offset into tile\r
- for (dx=((ts.hscroll-1)&7)+1; dx<328; dx+=8,tilex++)\r
- {\r
- int code=0,addr=0,zero=0;\r
- unsigned int *pal=NULL;\r
-\r
- code=Pico.vram[ts.nametab+(tilex&ts.xmask)];\r
- if (code==blank) continue;\r
- if ((code>>15)!=ts.high) { WrongPri=1; continue; }\r
-\r
- // Get tile address/2:\r
- addr=(code&0x7ff)<<4;\r
- if (code&0x1000) addr+=14-ty; else addr+=ty; // Y-flip\r
-\r
- pal=Pico.highpal+((code>>9)&0x30);\r
-\r
- if (code&0x0800) zero=TileFlip(HighCol+24+dx,addr,pal);\r
- else zero=TileNorm(HighCol+24+dx,addr,pal);\r
-\r
- if (zero) blank=code; // We know this tile is blank now\r
- }\r
-\r
- return 0;\r
-}\r
-\r
-static int DrawLayer(int plane,int high)\r
-{\r
- struct PicoVideo *pvid=&Pico.video;\r
- static char shift[4]={5,6,6,7}; // 32,64 or 128 sized tilemaps\r
- struct TileStrip ts;\r
-\r
- // Work out the TileStrip to draw\r
-\r
- // Get vertical scroll value:\r
- int vscroll=Pico.vsram[plane];\r
-\r
- int htab=pvid->reg[13]<<9; // Horizontal scroll table address\r
- if ( pvid->reg[11]&2) htab+=Scanline<<1; // Offset by line\r
- if ((pvid->reg[11]&1)==0) htab&=~0xf; // Offset by tile\r
- htab+=plane; // A or B\r
-\r
- // Get horizontal scroll value\r
- ts.hscroll=Pico.vram[htab&0x7fff];\r
-\r
- // Work out the name table size: 32 64 or 128 tiles (0-3)\r
- int width=pvid->reg[16];\r
- int height=(width>>4)&3; width&=3;\r
-\r
- ts.xmask=(1<<shift[width ])-1; // X Mask in tiles\r
- int ymask=(8<<shift[height])-1; // Y Mask in pixels\r
-\r
- // Find name table:\r
- if (plane==0) ts.nametab=(pvid->reg[2]&0x38)<< 9; // A\r
- else ts.nametab=(pvid->reg[4]&0x07)<<12; // B\r
-\r
- // Find the line in the name table\r
- ts.line=(vscroll+Scanline)&ymask;\r
- ts.nametab+=(ts.line>>3)<<shift[width];\r
-\r
- ts.high=high;\r
-\r
- DrawStrip(ts);\r
- return 0;\r
-}\r
-\r
-static int DrawWindow(int high)\r
-{\r
- struct PicoVideo *pvid=&Pico.video;\r
- struct TileStrip ts;\r
-\r
- ts.line=Scanline;\r
- ts.hscroll=0;\r
-\r
- // Find name table line:\r
- if (Pico.video.reg[12]&1)\r
- {\r
- ts.nametab=(pvid->reg[3]&0x3c)<<9; // 40-cell mode\r
- ts.nametab+=(ts.line>>3)<<6;\r
- }\r
- else\r
- {\r
- ts.nametab=(pvid->reg[3]&0x3e)<<9; // 32-cell mode\r
- ts.nametab+=(ts.line>>3)<<5;\r
- }\r
-\r
- ts.xmask=0x3f;\r
- ts.high=high;\r
-\r
- DrawStrip(ts);\r
- return 0;\r
-}\r
-\r
-static int DrawSprite(int sy,unsigned short *sprite,int high)\r
-{\r
- int sx=0,width=0,height=0;\r
- int row=0,code=0;\r
- unsigned int *pal=NULL;\r
- int tile=0,delta=0;\r
- int i=0;\r
-\r
- code=sprite[2];\r
- if ((code>>15)!=high) { WrongPri=1; return 0; } // Wrong priority\r
-\r
- height=sprite[1]>>8;\r
- width=(height>>2)&3; height&=3;\r
- width++; height++; // Width and height in tiles\r
- if (Scanline>=sy+(height<<3)) return 0; // Not on this line after all\r
-\r
- row=Scanline-sy; // Row of the sprite we are on\r
- pal=Pico.highpal+((code>>9)&0x30); // Get palette pointer\r
- if (code&0x1000) row=(height<<3)-1-row; // Flip Y\r
-\r
- tile=code&0x7ff; // Tile number\r
- tile+=row>>3; // Tile number increases going down\r
- delta=height; // Delta to increase tile by going right\r
- if (code&0x0800) { tile+=delta*(width-1); delta=-delta; } // Flip X\r
-\r
- tile<<=4; tile+=(row&7)<<1; // Tile address\r
- delta<<=4; // Delta of address\r
-\r
- sx=(sprite[3]&0x1ff)-0x78; // Get X coordinate + 8\r
-\r
- for (i=0; i<width; i++,sx+=8,tile+=delta)\r
- {\r
- if (sx<=0 || sx>=328) continue; // Offscreen\r
-\r
- tile&=0x7fff; // Clip tile address\r
- if (code&0x0800) TileFlip(HighCol+24+sx,tile,pal);\r
- else TileNorm(HighCol+24+sx,tile,pal);\r
- }\r
-\r
- return 0;\r
-}\r
-\r
-static int DrawAllSprites(int high)\r
-{\r
- struct PicoVideo *pvid=&Pico.video;\r
- int table=0;\r
- int i=0,link=0;\r
- unsigned char spin[80]; // Sprite index\r
-\r
- WrongPri=0;\r
-\r
- table=pvid->reg[5]&0x7f;\r
- if (pvid->reg[12]&1) table&=0x7e; // Lowest bit 0 in 40-cell mode\r
- table<<=8; // Get sprite table address/2\r
-\r
- for (;;)\r
- {\r
- unsigned short *sprite=NULL;\r
- \r
- spin[i]=(unsigned char)link;\r
- sprite=Pico.vram+((table+(link<<2))&0x7ffc); // Find sprite\r
-\r
- // Find next sprite\r
- link=sprite[1]&0x7f;\r
- if (link==0 || i>=79) break; // End of sprites\r
- i++;\r
- }\r
-\r
- // Go through sprites backwards:\r
- for ( ;i>=0; i--)\r
- {\r
- unsigned short *sprite=NULL;\r
- int sy=0;\r
- \r
- sprite=Pico.vram+((table+(spin[i]<<2))&0x7ffc); // Find sprite\r
-\r
- sy=(sprite[0]&0x1ff)-0x80; // Get Y coordinate\r
-\r
- if (Scanline>=sy && Scanline<sy+32) DrawSprite(sy,sprite,high); // Possibly on this line\r
- }\r
-\r
- return 0;\r
-}\r
-\r
-static void BackFill()\r
-{\r
- unsigned int back=0;\r
- unsigned int *pd=NULL,*end=NULL;\r
-\r
- // Start with a blank scanline (background colour):\r
- back=Pico.video.reg[7]&0x3f;\r
- back=Pico.highpal[back];\r
- back|=back<<16;\r
-\r
- pd= (unsigned int *)(HighCol+32);\r
- end=(unsigned int *)(HighCol+32+320);\r
-\r
- do { pd[0]=pd[1]=pd[2]=pd[3]=back; pd+=4; } while (pd<end);\r
-}\r
-\r
-static int DrawDisplay()\r
-{\r
- int win=0,edge=0,full=0;\r
- int bhigh=1,ahigh=1,shigh=1;\r
-\r
- // Find out if the window is on this line:\r
- win=Pico.video.reg[0x12];\r
- edge=(win&0x1f)<<3;\r
-\r
- if (win&0x80) { if (Scanline>=edge) full=1; }\r
- else { if (Scanline< edge) full=1; }\r
-\r
- if (PicoMask&0x04) { DrawLayer(1,0); bhigh=WrongPri; }\r
- if (PicoMask&0x08) { if (full) DrawWindow(0); else DrawLayer(0,0); ahigh=WrongPri; }\r
- if (PicoMask&0x10) { DrawAllSprites(0); shigh=WrongPri; }\r
- \r
- if (bhigh) if (PicoMask&0x20) DrawLayer(1,1);\r
- if (ahigh) if (PicoMask&0x40) { if (full) DrawWindow(1); else DrawLayer(0,1); }\r
- if (shigh) if (PicoMask&0x80) DrawAllSprites(1);\r
- return 0;\r
-}\r
-\r
-static int UpdatePalette()\r
-{\r
- int c=0;\r
-\r
- // Update palette:\r
- for (c=0;c<64;c++) Pico.highpal[c]=(unsigned short)PicoCram(Pico.cram[c]);\r
- Pico.m.dirtyPal=0;\r
-\r
- return 0;\r
-}\r
-\r
-static int Overlay()\r
-{\r
- int col=0,x=0;\r
-\r
- if (PmovAction==0) return 0;\r
- if (Scanline>=4) return 0;\r
-\r
- if (PmovAction&1) col =0x00f;\r
- if (PmovAction&2) col|=0x0f0;\r
- col=PicoCram(col);\r
-\r
- for (x=0;x<4;x++) HighCol[32+x]=(unsigned short)col;\r
-\r
- return 0;\r
-}\r
-\r
-static int Skip=0;\r
-\r
-\r
-int PicoLine(int scan)\r
-{\r
- if (Skip>0) { Skip--; return 0; } // Skip rendering lines\r
-\r
- Scanline=scan;\r
-\r
- if (Pico.m.dirtyPal) UpdatePalette();\r
-\r
- // Draw screen:\r
- if (PicoMask&0x02) BackFill();\r
- if (Pico.video.reg[1]&0x40) DrawDisplay();\r
-\r
- Overlay();\r
-\r
- if (Pico.video.reg[12]&1)\r
- {\r
- Skip=PicoScan(Scanline,HighCol+32); // 40-column mode\r
- }\r
- else\r
- {\r
- // Crop, centre and return 32-column mode\r
- memset(HighCol, 0,64); // Left border\r
- memset(HighCol+288,0,64); // Right border\r
- Skip=PicoScan(Scanline,HighCol);\r
- }\r
-\r
- return 0;\r
-}\r
-\r
notaz.gp2x.de / cyclone68000.git / blobdiff