+#include <dos.h>\r
+#include <string.h>\r
+#include <mem.h>\r
+#include <conio.h>\r
+#include <stdio.h>\r
+#include <stdlib.h>\r
+#include "modex16.h"\r
+\r
+\r
+byte far* VGA=(byte far*) 0xA0000000; /* this points to video memory. */\r
+\r
+static void fadePalette(sbyte fade, sbyte start, word iter, byte *palette);\r
+static byte tmppal[PAL_SIZE];\r
+static struct pcxHeader {\r
+ byte id;\r
+ byte version;\r
+ byte encoding;\r
+ byte bpp;\r
+ word xmin;\r
+ word ymin;\r
+ word xmax;\r
+ word ymax;\r
+ word hres;\r
+ word vres;\r
+ byte pal16[48];\r
+ byte res1;\r
+ word bpplane;\r
+ word palType;\r
+ word hScreenSize;\r
+ word vScreenSize;\r
+ byte padding[54];\r
+};\r
+\r
+\r
+static void\r
+vgaSetMode(byte mode)\r
+{\r
+ union REGS regs;\r
+\r
+ regs.h.ah = SET_MODE;\r
+ regs.h.al = mode;\r
+ int86(VIDEO_INT, ®s, ®s);\r
+}\r
+\r
+\r
+/* -========================= Entry Points ==========================- */\r
+void\r
+modexEnter() {\r
+ word i;\r
+ dword far*ptr=(dword far*)VGA; /* used for faster screen clearing */\r
+ word CRTParms[] = {\r
+ 0x0d06, /* vertical total */\r
+ 0x3e07, /* overflow (bit 8 of vertical counts) */\r
+ 0x4109, /* cell height (2 to double-scan */\r
+ 0xea10, /* v sync start */\r
+ 0xac11, /* v sync end and protect cr0-cr7 */\r
+ 0xdf12, /* vertical displayed */\r
+ 0x0014, /* turn off dword mode */\r
+ 0xe715, /* v blank start */\r
+ 0x0616, /* v blank end */\r
+ 0xe317 /* turn on byte mode */\r
+ };\r
+ int CRTParmCount = sizeof(CRTParms) / sizeof(CRTParms[0]);\r
+\r
+ /* TODO save current video mode and palette */\r
+ vgaSetMode(VGA_256_COLOR_MODE);\r
+\r
+ /* disable chain4 mode */\r
+ outpw(SC_INDEX, 0x0604);\r
+\r
+ /* synchronous reset while setting Misc Output */\r
+ outpw(SC_INDEX, 0x0100);\r
+\r
+ /* select 25 MHz dot clock & 60 Hz scanning rate */\r
+ outp(MISC_OUTPUT, 0xe3);\r
+\r
+ /* undo reset (restart sequencer) */\r
+ outpw(SC_INDEX, 0x0300);\r
+\r
+ /* reprogram the CRT controller */\r
+ outp(CRTC_INDEX, 0x11); /* VSync End reg contains register write prot */\r
+ outp(CRTC_DATA, 0x7f); /* get current write protect on varios regs */\r
+\r
+ /* send the CRTParms */\r
+ for(i=0; i<CRTParmCount; i++) {\r
+ outpw(CRTC_INDEX, CRTParms[i]);\r
+ }\r
+\r
+ /* clear video memory */\r
+ outpw(SC_INDEX, 0x0f02);\r
+ for(i=0; i<0x8000; i++) {\r
+ ptr[i] = 0x0000;\r
+ }\r
+}\r
+\r
+\r
+void\r
+modexLeave() {\r
+ /* TODO restore original mode and palette */\r
+ vgaSetMode(TEXT_MODE);\r
+}\r
+\r
+\r
+page_t\r
+modexDefaultPage() {\r
+ page_t page;\r
+\r
+ /* default page values */\r
+ page.data = VGA;\r
+ page.dx = 0;\r
+ page.dy = 0;\r
+ page.width = SCREEN_WIDTH;\r
+ page.height = SCREEN_HEIGHT;\r
+\r
+ return page;\r
+}\r
+\r
+/* returns the next page in contiguous memory\r
+ * the next page will be the same size as p, by default\r
+ */\r
+page_t\r
+modexNextPage(page_t *p) {\r
+ page_t result;\r
+\r
+ result.data = p->data + (p->width/4)*p->height; /* compute the offset */\r
+ result.dx = 0;\r
+ result.dy = 0;\r
+ result.width = p->width;\r
+ result.height = p->height;\r
+\r
+ return result;\r
+}\r
+\r
+\r
+void\r
+modexShowPage(page_t *page) {\r
+ word high_address;\r
+ word low_address;\r
+ word offset;\r
+ byte crtcOffset;\r
+\r
+ /* calculate offset */\r
+ offset = (word) page->data;\r
+ offset += page->dy * (page->width >> 2 );\r
+ offset += page->dx >> 2;\r
+\r
+ /* calculate crtcOffset according to virtual width */\r
+ crtcOffset = page->width >> 3;\r
+\r
+ high_address = HIGH_ADDRESS | (offset & 0xff00);\r
+ low_address = LOW_ADDRESS | (offset << 8);\r
+\r
+ /* wait for appropriate timing and then program CRTC */\r
+ while ((inp(INPUT_STATUS_1) & DISPLAY_ENABLE));\r
+ outpw(CRTC_INDEX, high_address);\r
+ outpw(CRTC_INDEX, low_address);\r
+ outp(CRTC_INDEX, 0x13);\r
+ outp(CRTC_DATA, crtcOffset);\r
+\r
+ /* wait for one retrace */\r
+ while (!(inp(INPUT_STATUS_1) & VRETRACE)); \r
+\r
+ /* do PEL panning here */\r
+ outp(AC_INDEX, 0x33);\r
+ outp(AC_INDEX, (page->dx & 0x03) << 1);\r
+}\r
+\r
+\r
+void\r
+modexPanPage(page_t *page, int dx, int dy) {\r
+ page->dx = dx;\r
+ page->dy = dy;\r
+}\r
+\r
+\r
+void\r
+modexSelectPlane(byte plane) {\r
+ outp(SC_INDEX, MAP_MASK); /* select plane */\r
+ outp(SC_DATA, plane);\r
+}\r
+\r
+\r
+void\r
+modexClearRegion(page_t *page, int x, int y, int w, int h, byte color) {\r
+ word pageOff = (word) page->data;\r
+ word xoff=x/4; /* xoffset that begins each row */\r
+ word scanCount=w/4; /* number of iterations per row (excluding right clip)*/\r
+ word poffset = pageOff + y*(page->width/4) + xoff; /* starting offset */\r
+ word nextRow = page->width/4-scanCount-1; /* loc of next row */\r
+ byte lclip[] = {0x0f, 0x0e, 0x0c, 0x08}; /* clips for rectangles not on 4s */\r
+ byte rclip[] = {0x00, 0x01, 0x03, 0x07};\r
+ byte left = lclip[x&0x03];\r
+ byte right = rclip[(x+w)&0x03];\r
+\r
+ /* handle the case which requires an extra group */\r
+ if((x & 0x03) && !((x+w) & 0x03)) {\r
+ right=0x0f;\r
+ }\r
+\r
+ __asm {\r
+ MOV AX, SCREEN_SEG ; go to the VGA memory\r
+ MOV ES, AX\r
+ MOV DI, poffset ; go to the first pixel\r
+ MOV DX, SC_INDEX ; point to the map mask\r
+ MOV AL, MAP_MASK\r
+ OUT DX, AL\r
+ INC DX\r
+ MOV AL, color ; get ready to write colors\r
+ SCAN_START:\r
+ MOV CX, scanCount ; count the line\r
+ MOV BL, AL ; remember color\r
+ MOV AL, left ; do the left clip\r
+ OUT DX, AL ; set the left clip\r
+ MOV AL, BL ; restore color\r
+ STOSB ; write the color\r
+ DEC CX\r
+ JZ SCAN_DONE ; handle 1 group stuff\r
+\r
+ ;-- write the main body of the scanline\r
+ MOV BL, AL ; remember color\r
+ MOV AL, 0x0f ; write to all pixels\r
+ OUT DX, AL\r
+ MOV AL, BL ; restore color\r
+ REP STOSB ; write the color\r
+ SCAN_DONE:\r
+ MOV BL, AL ; remeber color\r
+ MOV AL, right\r
+ OUT DX, AL ; do the right clip\r
+ MOV AL, BL ; restore color\r
+ STOSB ; write pixel\r
+ ADD DI, nextRow ; go to the next row\r
+ DEC h\r
+ JNZ SCAN_START\r
+ }\r
+}\r
+\r
+\r
+void\r
+modexDrawBmp(page_t *page, int x, int y, bitmap_t *bmp) {\r
+ /* draw the region (the entire freakin bitmap) */\r
+ modexDrawBmpRegion(page, x, y, 0, 0, bmp->width, bmp->height, bmp);\r
+}\r
+\r
+\r
+void\r
+modexDrawBmpRegion(page_t *page, int x, int y,\r
+ int rx, int ry, int rw, int rh, bitmap_t *bmp) {\r
+ word poffset = (word) page->data + y*(page->width/4) + x/4;\r
+ byte *data = bmp->data;\r
+ word bmpOffset = (word) data + ry * bmp->width + rx;\r
+ word width = rw;\r
+ word height = rh;\r
+ byte plane = 1 << ((byte) x & 0x03);\r
+ word scanCount = width/4 + (width%4 ? 1 :0);\r
+ word nextPageRow = page->width/4 - scanCount;\r
+ word nextBmpRow = (word) bmp->width - width;\r
+ word rowCounter;\r
+ byte planeCounter = 4;\r
+\r
+ __asm {\r
+ MOV AX, SCREEN_SEG ; go to the VGA memory\r
+ MOV ES, AX\r
+\r
+ MOV DX, SC_INDEX ; point at the map mask register\r
+ MOV AL, MAP_MASK ;\r
+ OUT DX, AL ;\r
+\r
+ PLANE_LOOP:\r
+ MOV DX, SC_DATA ; select the current plane\r
+ MOV AL, plane ;\r
+ OUT DX, AL ;\r
+\r
+ ;-- begin plane painting\r
+ MOV AX, height ; start the row counter\r
+ MOV rowCounter, AX ; \r
+ MOV DI, poffset ; go to the first pixel\r
+ MOV SI, bmpOffset ; go to the bmp pixel\r
+ ROW_LOOP:\r
+ MOV CX, width ; count the columns\r
+ SCAN_LOOP:\r
+ MOVSB ; copy the pixel\r
+ SUB CX, 3 ; we skip the next 3\r
+ ADD SI, 3 ; skip the bmp pixels\r
+ LOOP SCAN_LOOP ; finish the scan\r
+\r
+ MOV AX, nextPageRow\r
+ ADD DI, AX ; go to the next row on screen\r
+ MOV AX, nextBmpRow\r
+ ADD SI, AX ; go to the next row on bmp\r
+\r
+ DEC rowCounter\r
+ JNZ ROW_LOOP ; do all the rows\r
+ ;-- end plane painting\r
+\r
+ MOV AL, plane ; advance to the next plane\r
+ SHL AL, 1 ;\r
+ AND AL, 0x0f ; mask the plane properly\r
+ MOV plane, AL ; store the plane\r
+\r
+ INC bmpOffset ; start bmp at the right spot\r
+\r
+ DEC planeCounter\r
+ JNZ PLANE_LOOP ; do all 4 planes\r
+ }\r
+}\r
+\r
+\r
+void\r
+modexDrawSprite(page_t *page, int x, int y, bitmap_t *bmp) {\r
+ /* draw the whole sprite */\r
+ modexDrawSpriteRegion(page, x, y, 0, 0, bmp->width, bmp->height, bmp);\r
+}\r
+\r
+void\r
+modexDrawSpriteRegion(page_t *page, int x, int y,\r
+ int rx, int ry, int rw, int rh, bitmap_t *bmp) {\r
+ word poffset = (word)page->data + y*(page->width/4) + x/4;\r
+ byte *data = bmp->data;\r
+ word bmpOffset = (word) data + ry * bmp->width + rx;\r
+ word width = rw;\r
+ word height = rh;\r
+ byte plane = 1 << ((byte) x & 0x03);\r
+ word scanCount = width/4 + (width%4 ? 1 :0);\r
+ word nextPageRow = page->width/4 - scanCount;\r
+ word nextBmpRow = (word) bmp->width - width;\r
+ word rowCounter;\r
+ byte planeCounter = 4;\r
+\r
+ __asm {\r
+ MOV AX, SCREEN_SEG ; go to the VGA memory\r
+ MOV ES, AX\r
+\r
+ MOV DX, SC_INDEX ; point at the map mask register\r
+ MOV AL, MAP_MASK ;\r
+ OUT DX, AL ;\r
+\r
+ PLANE_LOOP:\r
+ MOV DX, SC_DATA ; select the current plane\r
+ MOV AL, plane ;\r
+ OUT DX, AL ;\r
+\r
+ ;-- begin plane painting\r
+ MOV AX, height ; start the row counter\r
+ MOV rowCounter, AX ; \r
+ MOV DI, poffset ; go to the first pixel\r
+ MOV SI, bmpOffset ; go to the bmp pixel\r
+ ROW_LOOP:\r
+ MOV CX, width ; count the columns\r
+ SCAN_LOOP:\r
+ LODSB\r
+ DEC SI\r
+ CMP AL, 0\r
+ JNE DRAW_PIXEL ; draw non-zero pixels\r
+\r
+ INC DI ; skip the transparent pixel\r
+ ADD SI, 1\r
+ JMP NEXT_PIXEL\r
+ DRAW_PIXEL:\r
+ MOVSB ; copy the pixel\r
+ NEXT_PIXEL:\r
+ SUB CX, 3 ; we skip the next 3\r
+ ADD SI, 3 ; skip the bmp pixels\r
+ LOOP SCAN_LOOP ; finish the scan\r
+\r
+ MOV AX, nextPageRow\r
+ ADD DI, AX ; go to the next row on screen\r
+ MOV AX, nextBmpRow\r
+ ADD SI, AX ; go to the next row on bmp\r
+\r
+ DEC rowCounter\r
+ JNZ ROW_LOOP ; do all the rows\r
+ ;-- end plane painting\r
+\r
+ MOV AL, plane ; advance to the next plane\r
+ SHL AL, 1 ;\r
+ AND AL, 0x0f ; mask the plane properly\r
+ MOV plane, AL ; store the plane\r
+\r
+ INC bmpOffset ; start bmp at the right spot\r
+\r
+ DEC planeCounter\r
+ JNZ PLANE_LOOP ; do all 4 planes\r
+ }\r
+}\r
+\r
+\r
+/* copy a region of video memory from one page to another.\r
+ * It assumes that the left edge of the tile is the same on both\r
+ * regions and the memory areas do not overlap.\r
+ */\r
+void\r
+modexCopyPageRegion(page_t *dest, page_t *src,\r
+ word sx, word sy,\r
+ word dx, word dy,\r
+ word width, word height)\r
+{\r
+ word doffset = (word)dest->data + dy*(dest->width/4) + dx/4;\r
+ word soffset = (word)src->data + sy*(src->width/4) + sx/4;\r
+ word scans = width/4;\r
+ word nextSrcRow = src->width/4 - scans - 1;\r
+ word nextDestRow = dest->width/4 - scans - 1;\r
+ byte lclip[] = {0x0f, 0x0e, 0x0c, 0x08}; /* clips for rectangles not on 4s */\r
+ byte rclip[] = {0x0f, 0x01, 0x03, 0x07};\r
+ byte left = lclip[sx&0x03];\r
+ byte right = rclip[(sx+width)&0x03];\r
+\r
+ __asm {\r
+ MOV AX, SCREEN_SEG ; work in the vga space\r
+ MOV ES, AX ;\r
+ MOV DI, doffset ;\r
+ MOV SI, soffset ;\r
+\r
+ MOV DX, GC_INDEX ; turn off cpu bits\r
+ MOV AX, 0008h ;\r
+ OUT DX, AX\r
+\r
+ MOV AX, SC_INDEX ; point to the mask register\r
+ MOV DX, AX ;\r
+ MOV AL, MAP_MASK ;\r
+ OUT DX, AL ;\r
+ INC DX ;\r
+\r
+ ROW_START:\r
+ PUSH DS\r
+ MOV AX, ES\r
+ MOV DS, AX\r
+ MOV CX, scans ; the number of latches\r
+\r
+ MOV AL, left ; do the left column\r
+ OUT DX, AL ;\r
+ MOVSB ;\r
+ DEC CX ;\r
+\r
+ MOV AL, 0fh ; do the inner columns\r
+ OUT DX, AL\r
+ REP MOVSB ; copy the pixels\r
+\r
+ MOV AL, right ; do the right column\r
+ OUT DX, AL\r
+ MOVSB\r
+ POP DS\r
+\r
+ MOV AX, SI ; go the start of the next row\r
+ ADD AX, nextSrcRow ;\r
+ MOV SI, AX ;\r
+ MOV AX, DI ;\r
+ ADD AX, nextDestRow ;\r
+ MOV DI, AX ;\r
+\r
+ DEC height ; do the rest of the actions\r
+ JNZ ROW_START ;\r
+\r
+ MOV DX, GC_INDEX+1 ; go back to CPU data\r
+ MOV AL, 0ffh ; none from latches\r
+ OUT DX, AL ;\r
+ }\r
+}\r
+\r
+\r
+/* fade and flash */\r
+void\r
+modexFadeOn(word fade, byte *palette) {\r
+ fadePalette(-fade, 64, 64/fade+1, palette);\r
+}\r
+\r
+\r
+void\r
+modexFadeOff(word fade, byte *palette) {\r
+ fadePalette(fade, 0, 64/fade+1, palette);\r
+}\r
+\r
+\r
+void\r
+modexFlashOn(word fade, byte *palette) {\r
+ fadePalette(fade, -64, 64/fade+1, palette);\r
+}\r
+\r
+\r
+void\r
+modexFlashOff(word fade, byte *palette) {\r
+ fadePalette(-fade, 0, 64/fade+1, palette);\r
+}\r
+\r
+\r
+static void\r
+fadePalette(sbyte fade, sbyte start, word iter, byte *palette) {\r
+ word i;\r
+ byte dim = start;\r
+\r
+ /* handle the case where we just update */\r
+ if(iter == 0) {\r
+ modexPalUpdate(palette);\r
+ return;\r
+ }\r
+\r
+ while(iter > 0) { /* FadeLoop */\r
+ for(i=0; i<PAL_SIZE; i++) { /* loadpal_loop */\r
+ tmppal[i] = palette[i] - dim;\r
+ if(tmppal[i] > 127) {\r
+ tmppal[i] = 0;\r
+ } else if(tmppal[i] > 63) {\r
+ tmppal[i] = 63;\r
+ }\r
+ }\r
+ modexPalUpdate(tmppal);\r
+ iter--;\r
+ dim += fade;\r
+ }\r
+}\r
+\r
+\r
+/* save and load */\r
+void\r
+modexPalSave(byte *palette) {\r
+ int i;\r
+\r
+ outp(PAL_READ_REG, 0); /* start at palette entry 0 */\r
+ for(i=0; i<PAL_SIZE; i++) {\r
+ palette[i] = inp(PAL_DATA_REG); /* read the palette data */\r
+ }\r
+}\r
+\r
+\r
+byte *\r
+modexNewPal() {\r
+ byte *ptr;\r
+ ptr = malloc(PAL_SIZE);\r
+\r
+ /* handle errors */\r
+ if(!ptr) {\r
+ printf("Could not allocate palette.\n");\r
+ exit(-1);\r
+ }\r
+\r
+ return ptr;\r
+}\r
+\r
+\r
+void\r
+modexLoadPalFile(byte *filename, byte **palette) {\r
+ FILE *file;\r
+ byte *ptr;\r
+\r
+ /* free the palette if it exists */\r
+ if(*palette) {\r
+ free(*palette);\r
+ }\r
+\r
+ /* allocate the new palette */\r
+ *palette = modexNewPal();\r
+\r
+ /* open the file */\r
+ file = fopen(filename, "rb");\r
+ if(!file) {\r
+ printf("Could not open palette file: %s\n", filename);\r
+ exit(-2);\r
+ }\r
+\r
+ /* read the file */\r
+ ptr = *palette;\r
+ while(!feof(file)) {\r
+ *ptr++ = fgetc(file);\r
+ }\r
+\r
+ fclose(file);\r
+}\r
+\r
+\r
+void\r
+modexSavePalFile(char *filename, byte *pal) {\r
+ unsigned int i;\r
+ FILE *file;\r
+\r
+ /* open the file for writing */\r
+ file = fopen(filename, "wb");\r
+ if(!file) {\r
+ printf("Could not open %s for writing\n", filename);\r
+ exit(-2);\r
+ }\r
+\r
+ /* write the data to the file */\r
+ fwrite(pal, 1, PAL_SIZE, file);\r
+ fclose(file);\r
+}\r
+\r
+\r
+/* blanking */\r
+void\r
+modexPalBlack() {\r
+ fadePalette(-1, 64, 1, tmppal);\r
+}\r
+\r
+\r
+void\r
+modexPalWhite() {\r
+ fadePalette(-1, -64, 1, tmppal);\r
+}\r
+\r
+\r
+/* utility */\r
+void\r
+modexPalUpdate(byte *p) {\r
+ int i;\r
+ modexWaitBorder();\r
+ outp(PAL_WRITE_REG, 0); /* start at the beginning of palette */\r
+ for(i=0; i<PAL_SIZE/2; i++) {\r
+ outp(PAL_DATA_REG, p[i]);\r
+ }\r
+ modexWaitBorder(); /* waits one retrace -- less flicker */\r
+ for(i=PAL_SIZE/2; i<PAL_SIZE; i++) {\r
+ outp(PAL_DATA_REG, p[i]);\r
+ }\r
+}\r
+\r
+\r
+void\r
+modexWaitBorder() {\r
+ while(inp(INPUT_STATUS_1) & 8) {\r
+ /* spin */\r
+ }\r
+\r
+ while(!(inp(INPUT_STATUS_1) & 8)) {\r
+ /* spin */\r
+ }\r
+}\r
+\r
+\r
+bitmap_t\r
+modexLoadPcx(char *filename) {\r
+ FILE *file;\r
+ bitmap_t result;\r
+ struct pcxHeader head;\r
+ long bufSize;\r
+ int index;\r
+ byte count, val;\r
+\r
+ /* open the PCX file for reading */\r
+ file = fopen(filename, "rb");\r
+ if(!file) {\r
+ printf("Could not open %s for reading.\n", filename);\r
+ exit(-2);\r
+ }\r
+\r
+ /* read the header */\r
+ fread(&head, sizeof(char), sizeof(struct pcxHeader), file);\r
+\r
+ /* make sure this is 8bpp */\r
+ if(head.bpp != 8) {\r
+ printf("I only know how to handle 8bpp pcx files!\n");\r
+ fclose(file);\r
+ exit(-2);\r
+ }\r
+\r
+ /* allocate the buffer */\r
+ result.width = head.xmax - head.xmin + 1;\r
+ result.height = head.ymax - head.ymin + 1;\r
+ bufSize = result.width * result.height;\r
+ result.data = malloc(bufSize);\r
+ if(!result.data) {\r
+ printf("Could not allocate memory for bitmap data.");\r
+ fclose(file);\r
+ exit(-1);\r
+ }\r
+\r
+ /* read the buffer in */\r
+ index = 0;\r
+ do {\r
+ /* get the run length and the value */\r
+ count = fgetc(file);\r
+ if(0xC0 == (count & 0xC0)) { /* this is the run count */\r
+ count &= 0x3f;\r
+ val = fgetc(file);\r
+ } else {\r
+ val = count;\r
+ count = 1;\r
+ }\r
+\r
+ /* write the pixel the specified number of times */\r
+ for(; count && index < bufSize; count--,index++) {\r
+ result.data[index] = val;\r
+ }\r
+ } while(index < bufSize);\r
+\r
+ /* handle the palette */\r
+ fseek(file, -769, SEEK_END);\r
+ val = fgetc(file);\r
+ result.palette = modexNewPal();\r
+ if(head.version == 5 && val == 12) {\r
+ /* use the vga palette */\r
+ for(index=0; !feof(file) && index < PAL_SIZE; index++) {\r
+ val = fgetc(file);\r
+ result.palette[index] = val >> 2;\r
+ }\r
+ } else {\r
+ /* use the 16 color palette */\r
+ for(index=0; index<48; index++) {\r
+ result.palette[index] = head.pal16[index];\r
+ }\r
+ }\r
+\r
+ fclose(file);\r
+\r
+ return result;\r
+}\r
projects / 16.git / commitdiff