src/tesuto.c

   1 #include <hw/cpu/cpu.h>
   2 #include <hw/dos/dos.h>
   3 #include <hw/vga/vga.h>
   4 #include <hw/vga/vrl.h>
   5
   6 #include "src/tesuto.h"
   7
   8 static unsigned char palette[768];
   9
  10 int main(int argc,char **argv) {
  11         struct vrl1_vgax_header *vrl_header;
  12         vrl1_vgax_offset_t *vrl_lineoffs;
  13         unsigned char *buffer;
  14         unsigned int bufsz;
  15         int fd;
  16
  17         if (argc < 3) {
  18                 fprintf(stderr,"drawvrl <VRL file> <palette file>\n");
  19                 return 1;
  20         }
  21
  22         fd = open(argv[1],O_RDONLY|O_BINARY);
  23         if (fd < 0) {
  24                 fprintf(stderr,"Unable to open '%s'\n",argv[1]);
  25                 return 1;
  26         }
  27         {
  28                 unsigned long sz = lseek(fd,0,SEEK_END);
  29                 if (sz < sizeof(*vrl_header)) return 1;
  30                 if (sz >= 65535UL) return 1;
  31
  32                 bufsz = (unsigned int)sz;
  33                 buffer = malloc(bufsz);
  34                 if (buffer == NULL) return 1;
  35
  36                 lseek(fd,0,SEEK_SET);
  37                 if ((unsigned int)read(fd,buffer,bufsz) < bufsz) return 1;
  38
  39                 vrl_header = (struct vrl1_vgax_header*)buffer;
  40                 if (memcmp(vrl_header->vrl_sig,"VRL1",4) || memcmp(vrl_header->fmt_sig,"VGAX",4)) return 1;
  41                 if (vrl_header->width == 0 || vrl_header->height == 0) return 1;
  42         }
  43         close(fd);
  44
  45         probe_dos();
  46         if (!probe_vga()) {
  47                 printf("VGA probe failed\n");
  48                 return 1;
  49         }
  50         int10_setmode(19);
  51         update_state_from_vga();
  52         vga_enable_256color_modex(); // VGA mode X
  53         vga_state.vga_width = 320; // VGA lib currently does not update this
  54         vga_state.vga_height = 240; // VGA lib currently does not update this
  55
  56 //#if 1 // 320x240 test mode: this is how Project 16 is using our code, enable for test case
  57         {
  58                 struct vga_mode_params cm;
  59
  60                 vga_read_crtc_mode(&cm);
  61
  62                 // 320x240 mode 60Hz
  63                 cm.vertical_total = 525;
  64                 cm.vertical_start_retrace = 0x1EA;
  65                 cm.vertical_end_retrace = 0x1EC;
  66                 cm.vertical_display_end = 480;
  67                 cm.vertical_blank_start = 489;
  68                 cm.vertical_blank_end = 517;
  69
  70                 vga_write_crtc_mode(&cm,0);
  71         }
  72         vga_state.vga_height = 240; // VGA lib currently does not update this
  73 //#endif
  74
  75         /* load color palette */
  76         fd = open(argv[2],O_RDONLY|O_BINARY);
  77         if (fd >= 0) {
  78                 unsigned int i;
  79
  80                 read(fd,palette,768);
  81                 close(fd);
  82
  83                 vga_palette_lseek(0);
  84                 for (i=0;i < 256;i++) vga_palette_write(palette[(i*3)+0]>>2,palette[(i*3)+1]>>2,palette[(i*3)+2]>>2);
  85         }
  86
  87         /* preprocess the sprite to generate line offsets */
  88         vrl_lineoffs = vrl1_vgax_genlineoffsets(vrl_header,buffer+sizeof(*vrl_header),bufsz-sizeof(*vrl_header));
  89         if (vrl_lineoffs == NULL) return 1;
  90
  91         {
  92                 unsigned int i,j,o;
  93
  94                 /* fill screen with a distinctive pattern */
  95                 for (i=0;i < vga_state.vga_width;i++) {
  96                         o = i >> 2;
  97                         vga_write_sequencer(0x02/*map mask*/,1 << (i&3));
  98                         for (j=0;j < vga_state.vga_height;j++,o += vga_state.vga_stride)
  99                                 vga_state.vga_graphics_ram[o] = (i^j)&15; // VRL samples put all colors in first 15!
 100                 }
 101         }
 102         while (getch() != 13);
 103
 104         /* make distinctive pattern offscreen, render sprite, copy onscreen */
 105         {
 106                 const unsigned int offscreen_ofs = (vga_state.vga_stride * vga_state.vga_height);
 107                 unsigned int i,j,o,o2,x,y,rx,ry,w,h;
 108                 unsigned int overdraw = 1;      // how many pixels to "overdraw" so that moving sprites with edge pixels don't leave streaks.
 109                                                 // if the sprite's edge pixels are clear anyway, you can set this to 0.
 110                 VGA_RAM_PTR omemptr;
 111                 int xdir=1,ydir=1;
 112
 113                 /* starting coords. note: this technique is limited to x coordinates of multiple of 4 */
 114                 x = 0;
 115                 y = 0;
 116
 117                 /* do it */
 118                 omemptr = vga_state.vga_graphics_ram; // save original mem ptr
 119                 while (1) {
 120                         /* stop animating if the user hits ENTER */
 121                         if (kbhit()) {
 122                                 if (getch() == 13) break;
 123                         }
 124
 125                         /* render box bounds. y does not need modification, but x and width must be multiple of 4 */
 126                         if (x >= overdraw) rx = (x - overdraw) & (~3);
 127                         else rx = 0;
 128                         if (y >= overdraw) ry = (y - overdraw);
 129                         else ry = 0;
 130                         h = vrl_header->height + overdraw + y - ry;
 131                         w = (x + vrl_header->width + (overdraw*2) + 3/*round up*/ - rx) & (~3);
 132                         if ((rx+w) > vga_state.vga_width) w = vga_state.vga_width-rx;
 133                         if ((ry+h) > vga_state.vga_height) h = vga_state.vga_height-ry;
 134
 135                         /* replace VGA stride with our own and mem ptr. then sprite rendering at this stage is just (0,0) */
 136                         vga_state.vga_draw_stride_limit = (vga_state.vga_width + 3/*round up*/ - x) >> 2;
 137                         vga_state.vga_draw_stride = w >> 2;
 138                         vga_state.vga_graphics_ram = omemptr + offscreen_ofs;
 139
 140                         /* first draw pattern corresponding to that part of the screen. this COULD be optimized, obviously, but it's designed for study.
 141                          * also note we don't have to use the same stride as the display! */
 142                         for (i=rx;i < (rx+w);i++) {
 143                                 o = (i-rx) >> 2;
 144                                 vga_write_sequencer(0x02/*map mask*/,1 << (i&3));
 145                                 for (j=ry;j < (ry+h);j++,o += vga_state.vga_draw_stride)
 146                                         vga_state.vga_graphics_ram[o] = (i^j)&15; // VRL samples put all colors in first 15!
 147                         }
 148
 149                         /* then the sprite. note modding ram ptr means we just draw to (x&3,0) */
 150                         draw_vrl1_vgax_modex(x-rx,y-ry,vrl_header,vrl_lineoffs,buffer+sizeof(*vrl_header),bufsz-sizeof(*vrl_header));
 151
 152                         /* restore ptr */
 153                         vga_state.vga_graphics_ram = omemptr;
 154
 155                         /* block copy to visible RAM from offscreen */
 156                         vga_setup_wm1_block_copy();
 157                         o = offscreen_ofs; // source offscreen
 158                         o2 = (ry * vga_state.vga_stride) + (rx >> 2); // dest visible (original stride)
 159                         for (i=0;i < h;i++,o += vga_state.vga_draw_stride,o2 += vga_state.vga_stride) vga_wm1_mem_block_copy(o2,o,w >> 2);
 160                         /* must restore Write Mode 0/Read Mode 0 for this code to continue drawing normally */
 161                         vga_restore_rm0wm0();
 162
 163                         /* restore stride */
 164                         vga_state.vga_draw_stride_limit = vga_state.vga_draw_stride = vga_state.vga_stride;
 165
 166                         /* step */
 167                         x += xdir;
 168                         y += ydir;
 169                         if (x >= (vga_state.vga_width - 1) || x == 0)
 170                                 xdir = -xdir;
 171                         if (y >= (vga_state.vga_height - 1) || y == 0)
 172                                 ydir = -ydir;
 173                 }
 174         }
 175
 176         /* make distinctive pattern offscreen, render sprite, copy onscreen.
 177          * this time, we render the distinctive pattern to another offscreen location and just copy.
 178          * note this version is much faster too! */
 179         {
 180                 const unsigned int offscreen_ofs = (vga_state.vga_stride * vga_state.vga_height);
 181                 const unsigned int pattern_ofs = 0x10000UL - (vga_state.vga_stride * vga_state.vga_height);
 182                 unsigned int i,j,o,o2,x,y,rx,ry,w,h;
 183                 unsigned int overdraw = 1;      // how many pixels to "overdraw" so that moving sprites with edge pixels don't leave streaks.
 184                                                 // if the sprite's edge pixels are clear anyway, you can set this to 0.
 185                 VGA_RAM_PTR omemptr;
 186                 int xdir=1,ydir=1;
 187
 188                 /* fill pattern offset with a distinctive pattern */
 189                 for (i=0;i < vga_state.vga_width;i++) {
 190                         o = (i >> 2) + pattern_ofs;
 191                         vga_write_sequencer(0x02/*map mask*/,1 << (i&3));
 192                         for (j=0;j < vga_state.vga_height;j++,o += vga_state.vga_stride)
 193                                 vga_state.vga_graphics_ram[o] = (i^j)&15; // VRL samples put all colors in first 15!
 194                 }
 195
 196                 /* starting coords. note: this technique is limited to x coordinates of multiple of 4 */
 197                 x = 0;
 198                 y = 0;
 199
 200                 /* do it */
 201                 omemptr = vga_state.vga_graphics_ram; // save original mem ptr
 202                 while (1) {
 203                         /* stop animating if the user hits ENTER */
 204                         if (kbhit()) {
 205                                 if (getch() == 13) break;
 206                         }
 207
 208                         /* render box bounds. y does not need modification, but x and width must be multiple of 4 */
 209                         if (x >= overdraw) rx = (x - overdraw) & (~3);
 210                         else rx = 0;
 211                         if (y >= overdraw) ry = (y - overdraw);
 212                         else ry = 0;
 213                         h = vrl_header->height + overdraw + y - ry;
 214                         w = (x + vrl_header->width + (overdraw*2) + 3/*round up*/ - rx) & (~3);
 215                         if ((rx+w) > vga_state.vga_width) w = vga_state.vga_width-rx;
 216                         if ((ry+h) > vga_state.vga_height) h = vga_state.vga_height-ry;
 217
 218                         /* block copy pattern to where we will draw the sprite */
 219                         vga_setup_wm1_block_copy();
 220                         o2 = offscreen_ofs;
 221                         o = pattern_ofs + (ry * vga_state.vga_stride) + (rx >> 2); // source offscreen
 222                         for (i=0;i < h;i++,o += vga_state.vga_stride,o2 += (w >> 2)) vga_wm1_mem_block_copy(o2,o,w >> 2);
 223                         /* must restore Write Mode 0/Read Mode 0 for this code to continue drawing normally */
 224                         vga_restore_rm0wm0();
 225
 226                         /* replace VGA stride with our own and mem ptr. then sprite rendering at this stage is just (0,0) */
 227                         vga_state.vga_draw_stride_limit = (vga_state.vga_width + 3/*round up*/ - x) >> 2;
 228                         vga_state.vga_draw_stride = w >> 2;
 229                         vga_state.vga_graphics_ram = omemptr + offscreen_ofs;
 230
 231                         /* then the sprite. note modding ram ptr means we just draw to (x&3,0) */
 232                         draw_vrl1_vgax_modex(x-rx,y-ry,vrl_header,vrl_lineoffs,buffer+sizeof(*vrl_header),bufsz-sizeof(*vrl_header));
 233
 234                         /* restore ptr */
 235                         vga_state.vga_graphics_ram = omemptr;
 236
 237                         /* block copy to visible RAM from offscreen */
 238                         vga_setup_wm1_block_copy();
 239                         o = offscreen_ofs; // source offscreen
 240                         o2 = (ry * vga_state.vga_stride) + (rx >> 2); // dest visible (original stride)
 241                         for (i=0;i < h;i++,o += vga_state.vga_draw_stride,o2 += vga_state.vga_stride) vga_wm1_mem_block_copy(o2,o,w >> 2);
 242                         /* must restore Write Mode 0/Read Mode 0 for this code to continue drawing normally */
 243                         vga_restore_rm0wm0();
 244
 245                         /* restore stride */
 246                         vga_state.vga_draw_stride_limit = vga_state.vga_draw_stride = vga_state.vga_stride;
 247
 248                         /* step */
 249                         x += xdir;
 250                         y += ydir;
 251                         if (x >= (vga_state.vga_width - 1) || x == 0)
 252                                 xdir = -xdir;
 253                         if (y >= (vga_state.vga_height - 1) || y == 0)
 254                                 ydir = -ydir;
 255                 }
 256         }
 257
 258         /* another handy "demo" effect using VGA write mode 1.
 259          * we can take what's on screen and vertically squash it like an old analog TV set turning off. */
 260         {
 261                 unsigned int blank_line_ofs = (vga_state.vga_stride * vga_state.vga_height * 2);
 262                 unsigned int copy_ofs = (vga_state.vga_stride * vga_state.vga_height);
 263                 unsigned int display_ofs = 0x0000;
 264                 unsigned int i,y,soh,doh,dstart;
 265                 unsigned int dh_blankfill = 8;
 266                 unsigned int dh_step = 8;
 267                 uint32_t sh,dh,yf,ystep;
 268
 269                 /* copy active display (0) to offscreen buffer (0x4000) */
 270                 vga_state.vga_draw_stride_limit = vga_state.vga_draw_stride = vga_state.vga_stride;
 271                 vga_setup_wm1_block_copy();
 272                 vga_wm1_mem_block_copy(copy_ofs,display_ofs,vga_state.vga_stride * vga_state.vga_height);
 273                 vga_restore_rm0wm0();
 274
 275                 /* need a blank line as well */
 276                 for (i=0;i < vga_state.vga_stride;i++) vga_state.vga_graphics_ram[i+blank_line_ofs] = 0;
 277
 278                 sh = dh = vga_state.vga_height;
 279                 while (dh >= dh_step) {
 280                         /* stop animating if the user hits ENTER */
 281                         if (kbhit()) {
 282                                 if (getch() == 13) break;
 283                         }
 284
 285                         /* wait for vsync end */
 286                         vga_wait_for_vsync_end();
 287
 288                         /* what scalefactor to use for stretching? */
 289                         ystep = (0x10000UL * sh) / dh;
 290                         dstart = (vga_state.vga_height - dh) / 2; // center the squash effect on screen, otherwise it would squash to top of screen
 291                         doh = display_ofs;
 292                         soh = copy_ofs;
 293                         yf = 0;
 294                         y = 0;
 295
 296                         /* for performance, keep VGA in write mode 1 the entire render */
 297                         vga_setup_wm1_block_copy();
 298
 299                         /* blank lines */
 300                         if (dstart >= dh_blankfill) y = dstart - dh_blankfill;
 301                         else y = 0;
 302                         doh = vga_state.vga_stride * y;
 303
 304                         while (y < dstart) {
 305                                 vga_wm1_mem_block_copy(doh,blank_line_ofs,vga_state.vga_stride);
 306                                 doh += vga_state.vga_stride;
 307                                 y++;
 308                         }
 309
 310                         /* draw */
 311                         while (y < (dh+dstart)) {
 312                                 soh = copy_ofs + ((yf >> 16UL) * vga_state.vga_stride);
 313                                 vga_wm1_mem_block_copy(doh,soh,vga_state.vga_stride);
 314                                 doh += vga_state.vga_stride;
 315                                 yf += ystep;
 316                                 y++;
 317                         }
 318
 319                         /* blank lines */
 320                         while (y < vga_state.vga_height && y < (dh+dstart+dh_blankfill)) {
 321                                 vga_wm1_mem_block_copy(doh,blank_line_ofs,vga_state.vga_stride);
 322                                 doh += vga_state.vga_stride;
 323                                 y++;
 324                         }
 325
 326                         /* done */
 327                         vga_restore_rm0wm0();
 328
 329                         /* wait for vsync */
 330                         vga_wait_for_vsync();
 331
 332                         /* make it shrink */
 333                         dh -= dh_step;
 334                         if (dh < 40) dh_step = 1;
 335                 }
 336         }
 337
 338         int10_setmode(3);
 339         free(vrl_lineoffs);
 340         buffer = NULL;
 341         free(buffer);
 342         bufsz = 0;
 343         return 0;
 344 }
 345