| 1 | /*************************************************************************************** |
| 2 | * Genesis Plus |
| 3 | * CD graphics processor |
| 4 | * |
| 5 | * Copyright (C) 2012 Eke-Eke (Genesis Plus GX) |
| 6 | * |
| 7 | * Redistribution and use of this code or any derivative works are permitted |
| 8 | * provided that the following conditions are met: |
| 9 | * |
| 10 | * - Redistributions may not be sold, nor may they be used in a commercial |
| 11 | * product or activity. |
| 12 | * |
| 13 | * - Redistributions that are modified from the original source must include the |
| 14 | * complete source code, including the source code for all components used by a |
| 15 | * binary built from the modified sources. However, as a special exception, the |
| 16 | * source code distributed need not include anything that is normally distributed |
| 17 | * (in either source or binary form) with the major components (compiler, kernel, |
| 18 | * and so on) of the operating system on which the executable runs, unless that |
| 19 | * component itself accompanies the executable. |
| 20 | * |
| 21 | * - Redistributions must reproduce the above copyright notice, this list of |
| 22 | * conditions and the following disclaimer in the documentation and/or other |
| 23 | * materials provided with the distribution. |
| 24 | * |
| 25 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| 26 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 27 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 28 | * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| 29 | * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 30 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 31 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 32 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 33 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 34 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 35 | * POSSIBILITY OF SUCH DAMAGE. |
| 36 | * |
| 37 | ****************************************************************************************/ |
| 38 | #include "../pico_int.h" |
| 39 | #include "genplus_macros.h" |
| 40 | |
| 41 | typedef struct |
| 42 | { |
| 43 | //uint32 cycles; /* current cycles count for graphics operation */ |
| 44 | //uint32 cyclesPerLine; /* current graphics operation timings */ |
| 45 | uint32 dotMask; /* stamp map size mask */ |
| 46 | uint16 *tracePtr; /* trace vector pointer */ |
| 47 | uint16 *mapPtr; /* stamp map table base address */ |
| 48 | uint8 stampShift; /* stamp pixel shift value (related to stamp size) */ |
| 49 | uint8 mapShift; /* stamp map table shift value (related to stamp map size) */ |
| 50 | uint16 bufferOffset; /* image buffer column offset */ |
| 51 | uint32 bufferStart; /* image buffer start index */ |
| 52 | uint32 y_step; /* pico: render line step */ |
| 53 | uint8 lut_prio[4][0x10][0x10]; /* WORD-RAM data writes priority lookup table */ |
| 54 | uint8 lut_pixel[0x200]; /* Graphics operation dot offset lookup table */ |
| 55 | uint8 lut_cell[0x100]; /* Graphics operation stamp offset lookup table */ |
| 56 | } gfx_t; |
| 57 | |
| 58 | static gfx_t gfx; |
| 59 | |
| 60 | static void gfx_schedule(void); |
| 61 | |
| 62 | /***************************************************************/ |
| 63 | /* Rotation / Scaling operation (2M Mode) */ |
| 64 | /***************************************************************/ |
| 65 | |
| 66 | void gfx_init(void) |
| 67 | { |
| 68 | int i, j; |
| 69 | uint8 mask, row, col, temp; |
| 70 | |
| 71 | memset(&gfx, 0, sizeof(gfx)); |
| 72 | |
| 73 | /* Initialize priority modes lookup table */ |
| 74 | for (i = 0; i < 0x10; i++) |
| 75 | { |
| 76 | for (j = 0; j < 0x10; j++) |
| 77 | { |
| 78 | /* normal */ |
| 79 | gfx.lut_prio[0][i][j] = j; |
| 80 | /* underwrite */ |
| 81 | gfx.lut_prio[1][i][j] = i ? i : j; |
| 82 | /* overwrite */ |
| 83 | gfx.lut_prio[2][i][j] = j ? j : i; |
| 84 | /* invalid */ |
| 85 | gfx.lut_prio[3][i][j] = i; |
| 86 | } |
| 87 | } |
| 88 | |
| 89 | /* Initialize cell lookup table */ |
| 90 | /* table entry = yyxxshrr (8 bits) */ |
| 91 | /* with: yy = cell row (0-3) */ |
| 92 | /* xx = cell column (0-3) */ |
| 93 | /* s = stamp size (0=16x16, 1=32x32) */ |
| 94 | /* hrr = HFLIP & ROTATION bits */ |
| 95 | for (i=0; i<0x100; i++) |
| 96 | { |
| 97 | /* one stamp = 2x2 cells (16x16) or 4x4 cells (32x32) */ |
| 98 | mask = (i & 8) ? 3 : 1; |
| 99 | row = (i >> 6) & mask; |
| 100 | col = (i >> 4) & mask; |
| 101 | |
| 102 | if (i & 4) { col = col ^ mask; } /* HFLIP (always first) */ |
| 103 | if (i & 2) { col = col ^ mask; row = row ^ mask; } /* ROLL1 */ |
| 104 | if (i & 1) { temp = col; col = row ^ mask; row = temp; } /* ROLL0 */ |
| 105 | |
| 106 | /* cell offset (0-3 or 0-15) */ |
| 107 | gfx.lut_cell[i] = row + col * (mask + 1); |
| 108 | } |
| 109 | |
| 110 | /* Initialize pixel lookup table */ |
| 111 | /* table entry = yyyxxxhrr (9 bits) */ |
| 112 | /* with: yyy = pixel row (0-7) */ |
| 113 | /* xxx = pixel column (0-7) */ |
| 114 | /* hrr = HFLIP & ROTATION bits */ |
| 115 | for (i=0; i<0x200; i++) |
| 116 | { |
| 117 | /* one cell = 8x8 pixels */ |
| 118 | row = (i >> 6) & 7; |
| 119 | col = (i >> 3) & 7; |
| 120 | |
| 121 | if (i & 4) { col = col ^ 7; } /* HFLIP (always first) */ |
| 122 | if (i & 2) { col = col ^ 7; row = row ^ 7; } /* ROLL1 */ |
| 123 | if (i & 1) { temp = col; col = row ^ 7; row = temp; } /* ROLL0 */ |
| 124 | |
| 125 | /* pixel offset (0-63) */ |
| 126 | gfx.lut_pixel[i] = col + row * 8; |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | int gfx_context_save(uint8 *state) |
| 131 | { |
| 132 | uint32 tmp32; |
| 133 | int bufferptr = 0; |
| 134 | |
| 135 | //save_param(&gfx.cycles, sizeof(gfx.cycles)); |
| 136 | //save_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine)); |
| 137 | save_param(&gfx.dotMask, sizeof(gfx.dotMask)); |
| 138 | save_param(&gfx.stampShift, sizeof(gfx.stampShift)); |
| 139 | save_param(&gfx.mapShift, sizeof(gfx.mapShift)); |
| 140 | save_param(&gfx.bufferOffset, sizeof(gfx.bufferOffset)); |
| 141 | save_param(&gfx.bufferStart, sizeof(gfx.bufferStart)); |
| 142 | |
| 143 | tmp32 = (uint8 *)(gfx.tracePtr) - Pico_mcd->word_ram2M; |
| 144 | save_param(&tmp32, 4); |
| 145 | |
| 146 | tmp32 = (uint8 *)(gfx.mapPtr) - Pico_mcd->word_ram2M; |
| 147 | save_param(&tmp32, 4); |
| 148 | |
| 149 | save_param(&gfx.y_step, sizeof(gfx.y_step)); |
| 150 | |
| 151 | return bufferptr; |
| 152 | } |
| 153 | |
| 154 | int gfx_context_load(const uint8 *state) |
| 155 | { |
| 156 | uint32 tmp32; |
| 157 | int bufferptr = 0; |
| 158 | |
| 159 | //load_param(&gfx.cycles, sizeof(gfx.cycles)); |
| 160 | //load_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine)); |
| 161 | load_param(&gfx.dotMask, sizeof(gfx.dotMask)); |
| 162 | load_param(&gfx.stampShift, sizeof(gfx.stampShift)); |
| 163 | load_param(&gfx.mapShift, sizeof(gfx.mapShift)); |
| 164 | load_param(&gfx.bufferOffset, sizeof(gfx.bufferOffset)); |
| 165 | load_param(&gfx.bufferStart, sizeof(gfx.bufferStart)); |
| 166 | |
| 167 | load_param(&tmp32, 4); |
| 168 | gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32); |
| 169 | |
| 170 | load_param(&tmp32, 4); |
| 171 | gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32); |
| 172 | |
| 173 | load_param(&gfx.y_step, sizeof(gfx.y_step)); |
| 174 | |
| 175 | return bufferptr; |
| 176 | } |
| 177 | |
| 178 | static void gfx_render(uint32 bufferIndex, uint32 width) |
| 179 | { |
| 180 | uint8 pixel_in, pixel_out; |
| 181 | uint16 stamp_data; |
| 182 | uint32 stamp_index; |
| 183 | uint32 priority; |
| 184 | |
| 185 | /* pixel map start position for current line (13.3 format converted to 13.11) */ |
| 186 | uint32 xpos = *gfx.tracePtr++ << 8; |
| 187 | uint32 ypos = *gfx.tracePtr++ << 8; |
| 188 | |
| 189 | /* pixel map offset values for current line (5.11 format) */ |
| 190 | uint32 xoffset = (int16) *gfx.tracePtr++; |
| 191 | uint32 yoffset = (int16) *gfx.tracePtr++; |
| 192 | |
| 193 | priority = (Pico_mcd->s68k_regs[2] << 8) | Pico_mcd->s68k_regs[3]; |
| 194 | priority = (priority >> 3) & 0x03; |
| 195 | |
| 196 | /* process all dots */ |
| 197 | while (width--) |
| 198 | { |
| 199 | /* check if stamp map is repeated */ |
| 200 | if (Pico_mcd->s68k_regs[0x58+1] & 0x01) |
| 201 | { |
| 202 | /* stamp map range */ |
| 203 | xpos &= gfx.dotMask; |
| 204 | ypos &= gfx.dotMask; |
| 205 | } |
| 206 | else |
| 207 | { |
| 208 | /* 24-bit range */ |
| 209 | xpos &= 0xffffff; |
| 210 | ypos &= 0xffffff; |
| 211 | } |
| 212 | |
| 213 | /* check if pixel is outside stamp map */ |
| 214 | if ((xpos | ypos) & ~gfx.dotMask) |
| 215 | { |
| 216 | /* force pixel output to 0 */ |
| 217 | pixel_out = 0x00; |
| 218 | } |
| 219 | else |
| 220 | { |
| 221 | /* read stamp map table data */ |
| 222 | stamp_data = gfx.mapPtr[(xpos >> gfx.stampShift) | ((ypos >> gfx.stampShift) << gfx.mapShift)]; |
| 223 | |
| 224 | /* stamp generator base index */ |
| 225 | /* sss ssssssss ccyyyxxx (16x16) or sss sssssscc ccyyyxxx (32x32) */ |
| 226 | /* with: s = stamp number (1 stamp = 16x16 or 32x32 pixels) */ |
| 227 | /* c = cell offset (0-3 for 16x16, 0-15 for 32x32) */ |
| 228 | /* yyy = line offset (0-7) */ |
| 229 | /* xxx = pixel offset (0-7) */ |
| 230 | stamp_index = (stamp_data & 0x7ff) << 8; |
| 231 | |
| 232 | if (stamp_index) |
| 233 | { |
| 234 | /* extract HFLIP & ROTATION bits */ |
| 235 | stamp_data = (stamp_data >> 13) & 7; |
| 236 | |
| 237 | /* cell offset (0-3 or 0-15) */ |
| 238 | /* table entry = yyxxshrr (8 bits) */ |
| 239 | /* with: yy = cell row (0-3) = (ypos >> (11 + 3)) & 3 */ |
| 240 | /* xx = cell column (0-3) = (xpos >> (11 + 3)) & 3 */ |
| 241 | /* s = stamp size (0=16x16, 1=32x32) */ |
| 242 | /* hrr = HFLIP & ROTATION bits */ |
| 243 | stamp_index |= gfx.lut_cell[ |
| 244 | stamp_data | ((Pico_mcd->s68k_regs[0x58+1] & 0x02) << 2 ) |
| 245 | | ((ypos >> 8) & 0xc0) | ((xpos >> 10) & 0x30)] << 6; |
| 246 | |
| 247 | /* pixel offset (0-63) */ |
| 248 | /* table entry = yyyxxxhrr (9 bits) */ |
| 249 | /* with: yyy = pixel row (0-7) = (ypos >> 11) & 7 */ |
| 250 | /* xxx = pixel column (0-7) = (xpos >> 11) & 7 */ |
| 251 | /* hrr = HFLIP & ROTATION bits */ |
| 252 | stamp_index |= gfx.lut_pixel[stamp_data | ((xpos >> 8) & 0x38) | ((ypos >> 5) & 0x1c0)]; |
| 253 | |
| 254 | /* read pixel pair (2 pixels/byte) */ |
| 255 | pixel_out = READ_BYTE(Pico_mcd->word_ram2M, stamp_index >> 1); |
| 256 | |
| 257 | /* extract left or rigth pixel */ |
| 258 | if (stamp_index & 1) |
| 259 | { |
| 260 | pixel_out &= 0x0f; |
| 261 | } |
| 262 | else |
| 263 | { |
| 264 | pixel_out >>= 4; |
| 265 | } |
| 266 | } |
| 267 | else |
| 268 | { |
| 269 | /* stamp 0 is not used: force pixel output to 0 */ |
| 270 | pixel_out = 0x00; |
| 271 | } |
| 272 | } |
| 273 | |
| 274 | /* read out paired pixel data */ |
| 275 | pixel_in = READ_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1); |
| 276 | |
| 277 | /* update left or rigth pixel */ |
| 278 | if (bufferIndex & 1) |
| 279 | { |
| 280 | /* priority mode write */ |
| 281 | pixel_out = gfx.lut_prio[priority][pixel_in & 0x0f][pixel_out]; |
| 282 | |
| 283 | pixel_out |= (pixel_in & 0xf0); |
| 284 | } |
| 285 | else |
| 286 | { |
| 287 | /* priority mode write */ |
| 288 | pixel_out = gfx.lut_prio[priority][pixel_in >> 4][pixel_out]; |
| 289 | |
| 290 | pixel_out = (pixel_out << 4) | (pixel_in & 0x0f); |
| 291 | } |
| 292 | |
| 293 | /* write data to image buffer */ |
| 294 | WRITE_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1, pixel_out); |
| 295 | |
| 296 | /* check current pixel position */ |
| 297 | if ((bufferIndex & 7) != 7) |
| 298 | { |
| 299 | /* next pixel */ |
| 300 | bufferIndex++; |
| 301 | } |
| 302 | else |
| 303 | { |
| 304 | /* next cell: increment image buffer offset by one column (minus 7 pixels) */ |
| 305 | bufferIndex += gfx.bufferOffset; |
| 306 | } |
| 307 | |
| 308 | /* increment pixel position */ |
| 309 | xpos += xoffset; |
| 310 | ypos += yoffset; |
| 311 | } |
| 312 | } |
| 313 | |
| 314 | void gfx_start(unsigned int base) |
| 315 | { |
| 316 | /* make sure 2M mode is enabled */ |
| 317 | if (!(Pico_mcd->s68k_regs[3] & 0x04)) |
| 318 | { |
| 319 | uint32 mask = 0; |
| 320 | uint32 reg; |
| 321 | |
| 322 | /* trace vector pointer */ |
| 323 | gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + ((base << 2) & 0x3fff8)); |
| 324 | |
| 325 | /* stamps & stamp map size */ |
| 326 | switch ((Pico_mcd->s68k_regs[0x58+1] >> 1) & 0x03) |
| 327 | { |
| 328 | case 0: |
| 329 | gfx.dotMask = 0x07ffff; /* 256x256 dots/map */ |
| 330 | gfx.stampShift = 11 + 4; /* 16x16 dots/stamps */ |
| 331 | gfx.mapShift = 4; /* 16x16 stamps/map */ |
| 332 | mask = 0x3fe00; /* 512 bytes/table */ |
| 333 | break; |
| 334 | |
| 335 | case 1: |
| 336 | gfx.dotMask = 0x07ffff; /* 256x256 dots/map */ |
| 337 | gfx.stampShift = 11 + 5; /* 32x32 dots/stamps */ |
| 338 | gfx.mapShift = 3; /* 8x8 stamps/map */ |
| 339 | mask = 0x3ff80; /* 128 bytes/table */ |
| 340 | break; |
| 341 | |
| 342 | case 2: |
| 343 | gfx.dotMask = 0x7fffff; /* 4096*4096 dots/map */ |
| 344 | gfx.stampShift = 11 + 4; /* 16x16 dots/stamps */ |
| 345 | gfx.mapShift = 8; /* 256x256 stamps/map */ |
| 346 | mask = 0x20000; /* 131072 bytes/table */ |
| 347 | break; |
| 348 | |
| 349 | case 3: |
| 350 | gfx.dotMask = 0x7fffff; /* 4096*4096 dots/map */ |
| 351 | gfx.stampShift = 11 + 5; /* 32x32 dots/stamps */ |
| 352 | gfx.mapShift = 7; /* 128x128 stamps/map */ |
| 353 | mask = 0x38000; /* 32768 bytes/table */ |
| 354 | break; |
| 355 | } |
| 356 | |
| 357 | /* stamp map table base address */ |
| 358 | reg = (Pico_mcd->s68k_regs[0x5a] << 8) | Pico_mcd->s68k_regs[0x5b]; |
| 359 | gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + ((reg << 2) & mask)); |
| 360 | |
| 361 | /* image buffer column offset (64 pixels/cell, minus 7 pixels to restart at cell beginning) */ |
| 362 | gfx.bufferOffset = (((Pico_mcd->s68k_regs[0x5c+1] & 0x1f) + 1) << 6) - 7; |
| 363 | |
| 364 | /* image buffer start index in dot units (2 pixels/byte) */ |
| 365 | reg = (Pico_mcd->s68k_regs[0x5e] << 8) | Pico_mcd->s68k_regs[0x5f]; |
| 366 | gfx.bufferStart = (reg << 3) & 0x7ffc0; |
| 367 | |
| 368 | /* add image buffer horizontal dot offset */ |
| 369 | gfx.bufferStart += (Pico_mcd->s68k_regs[0x60+1] & 0x3f); |
| 370 | |
| 371 | /* reset GFX chip cycle counter */ |
| 372 | //gfx.cycles = cycles; |
| 373 | |
| 374 | /* update GFX chip timings (see AC3:Thunderhawk / Thunderstrike) */ |
| 375 | //gfx.cyclesPerLine = 4 * 5 * scd.regs[0x62>>1].w; |
| 376 | |
| 377 | /* start graphics operation */ |
| 378 | Pico_mcd->s68k_regs[0x58] = 0x80; |
| 379 | |
| 380 | gfx_schedule(); |
| 381 | } |
| 382 | } |
| 383 | |
| 384 | /* PicoDrive specific */ |
| 385 | #define UPDATE_CYCLES 20000 |
| 386 | |
| 387 | static void gfx_schedule(void) |
| 388 | { |
| 389 | int w, h, cycles; |
| 390 | int y_step; |
| 391 | |
| 392 | w = (Pico_mcd->s68k_regs[0x62] << 8) | Pico_mcd->s68k_regs[0x63]; |
| 393 | h = (Pico_mcd->s68k_regs[0x64] << 8) | Pico_mcd->s68k_regs[0x65]; |
| 394 | |
| 395 | cycles = 5 * w * h; |
| 396 | if (cycles > UPDATE_CYCLES) |
| 397 | y_step = (UPDATE_CYCLES + 5 * w - 1) / (5 * w); |
| 398 | else |
| 399 | y_step = h; |
| 400 | |
| 401 | gfx.y_step = y_step; |
| 402 | pcd_event_schedule_s68k(PCD_EVENT_GFX, 5 * w * y_step); |
| 403 | } |
| 404 | |
| 405 | void gfx_update(unsigned int cycles) |
| 406 | { |
| 407 | int lines, lines_reg; |
| 408 | int w; |
| 409 | |
| 410 | if (!(Pico_mcd->s68k_regs[0x58] & 0x80)) |
| 411 | return; |
| 412 | |
| 413 | w = (Pico_mcd->s68k_regs[0x62] << 8) | Pico_mcd->s68k_regs[0x63]; |
| 414 | lines = (Pico_mcd->s68k_regs[0x64] << 8) | Pico_mcd->s68k_regs[0x65]; |
| 415 | lines_reg = lines - gfx.y_step; |
| 416 | |
| 417 | if (lines_reg <= 0) { |
| 418 | Pico_mcd->s68k_regs[0x58] = 0; |
| 419 | Pico_mcd->s68k_regs[0x64] = |
| 420 | Pico_mcd->s68k_regs[0x65] = 0; |
| 421 | |
| 422 | if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN1) { |
| 423 | elprintf(EL_INTS|EL_CD, "s68k: gfx_cd irq 1"); |
| 424 | SekInterruptS68k(1); |
| 425 | } |
| 426 | } |
| 427 | else { |
| 428 | Pico_mcd->s68k_regs[0x64] = lines_reg >> 8; |
| 429 | Pico_mcd->s68k_regs[0x65] = lines_reg; |
| 430 | |
| 431 | if (lines > gfx.y_step) |
| 432 | lines = gfx.y_step; |
| 433 | |
| 434 | pcd_event_schedule(cycles, PCD_EVENT_GFX, 5 * w * lines); |
| 435 | } |
| 436 | |
| 437 | if (PicoOpt & POPT_EN_MCD_GFX) |
| 438 | { |
| 439 | /* render lines */ |
| 440 | while (lines--) |
| 441 | { |
| 442 | /* process dots to image buffer */ |
| 443 | gfx_render(gfx.bufferStart, w); |
| 444 | |
| 445 | /* increment image buffer start index for next line (8 pixels/line) */ |
| 446 | gfx.bufferStart += 8; |
| 447 | } |
| 448 | } |
| 449 | } |
| 450 | |
| 451 | // vim:shiftwidth=2:ts=2:expandtab |