1 /***************************************************************************************
3 * CD graphics processor
5 * Copyright (C) 2012 Eke-Eke (Genesis Plus GX)
7 * Redistribution and use of this code or any derivative works are permitted
8 * provided that the following conditions are met:
10 * - Redistributions may not be sold, nor may they be used in a commercial
11 * product or activity.
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.
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.
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.
37 ****************************************************************************************/
38 #include "../pico_int.h"
39 #include "genplus_macros.h"
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][0x100][0x100]; /* 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 */
60 static void gfx_schedule(void);
62 /***************************************************************/
63 /* Rotation / Scaling operation (2M Mode) */
64 /***************************************************************/
69 uint8 mask, row, col, temp;
71 memset(&gfx, 0, sizeof(gfx));
73 /* Initialize priority modes lookup table */
74 for (i=0; i<0x100; i++)
76 for (j=0; j<0x100; j++)
79 gfx.lut_prio[0][i][j] = j;
81 gfx.lut_prio[1][i][j] = ((i & 0x0f) ? (i & 0x0f) : (j & 0x0f)) | ((i & 0xf0) ? (i & 0xf0) : (j & 0xf0));
83 gfx.lut_prio[2][i][j] = ((j & 0x0f) ? (j & 0x0f) : (i & 0x0f)) | ((j & 0xf0) ? (j & 0xf0) : (i & 0xf0));
85 gfx.lut_prio[3][i][j] = i;
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++)
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;
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 */
106 /* cell offset (0-3 or 0-15) */
107 gfx.lut_cell[i] = row + col * (mask + 1);
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++)
117 /* one cell = 8x8 pixels */
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 */
125 /* pixel offset (0-63) */
126 gfx.lut_pixel[i] = col + row * 8;
130 int gfx_context_save(uint8 *state)
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));
143 tmp32 = (uint8 *)(gfx.tracePtr) - Pico_mcd->word_ram2M;
144 save_param(&tmp32, 4);
146 tmp32 = (uint8 *)(gfx.mapPtr) - Pico_mcd->word_ram2M;
147 save_param(&tmp32, 4);
149 save_param(&gfx.y_step, sizeof(gfx.y_step));
154 int gfx_context_load(const uint8 *state)
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));
167 load_param(&tmp32, 4);
168 gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32);
170 load_param(&tmp32, 4);
171 gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32);
173 load_param(&gfx.y_step, sizeof(gfx.y_step));
178 static void gfx_render(uint32 bufferIndex, uint32 width)
180 uint8 pixel_in, pixel_out;
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;
189 /* pixel map offset values for current line (5.11 format) */
190 uint32 xoffset = (int16) *gfx.tracePtr++;
191 uint32 yoffset = (int16) *gfx.tracePtr++;
193 /* process all dots */
196 /* check if stamp map is repeated */
197 if (Pico_mcd->s68k_regs[0x58+1] & 0x01)
199 /* stamp map range */
210 /* check if pixel is outside stamp map */
211 if ((xpos | ypos) & ~gfx.dotMask)
213 /* force pixel output to 0 */
218 /* read stamp map table data */
219 stamp_data = gfx.mapPtr[(xpos >> gfx.stampShift) | ((ypos >> gfx.stampShift) << gfx.mapShift)];
221 /* stamp generator base index */
222 /* sss ssssssss ccyyyxxx (16x16) or sss sssssscc ccyyyxxx (32x32) */
223 /* with: s = stamp number (1 stamp = 16x16 or 32x32 pixels) */
224 /* c = cell offset (0-3 for 16x16, 0-15 for 32x32) */
225 /* yyy = line offset (0-7) */
226 /* xxx = pixel offset (0-7) */
227 stamp_index = (stamp_data & 0x7ff) << 8;
231 /* extract HFLIP & ROTATION bits */
232 stamp_data = (stamp_data >> 13) & 7;
234 /* cell offset (0-3 or 0-15) */
235 /* table entry = yyxxshrr (8 bits) */
236 /* with: yy = cell row (0-3) = (ypos >> (11 + 3)) & 3 */
237 /* xx = cell column (0-3) = (xpos >> (11 + 3)) & 3 */
238 /* s = stamp size (0=16x16, 1=32x32) */
239 /* hrr = HFLIP & ROTATION bits */
240 stamp_index |= gfx.lut_cell[
241 stamp_data | ((Pico_mcd->s68k_regs[0x58+1] & 0x02) << 2 )
242 | ((ypos >> 8) & 0xc0) | ((xpos >> 10) & 0x30)] << 6;
244 /* pixel offset (0-63) */
245 /* table entry = yyyxxxhrr (9 bits) */
246 /* with: yyy = pixel row (0-7) = (ypos >> 11) & 7 */
247 /* xxx = pixel column (0-7) = (xpos >> 11) & 7 */
248 /* hrr = HFLIP & ROTATION bits */
249 stamp_index |= gfx.lut_pixel[stamp_data | ((xpos >> 8) & 0x38) | ((ypos >> 5) & 0x1c0)];
251 /* read pixel pair (2 pixels/byte) */
252 pixel_out = READ_BYTE(Pico_mcd->word_ram2M, stamp_index >> 1);
254 /* extract left or rigth pixel */
266 /* stamp 0 is not used: force pixel output to 0 */
271 /* read out paired pixel data */
272 pixel_in = READ_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1);
274 /* update left or rigth pixel */
277 pixel_out |= (pixel_in & 0xf0);
281 pixel_out = (pixel_out << 4) | (pixel_in & 0x0f);
284 /* priority mode write */
285 reg = (Pico_mcd->s68k_regs[2] << 8) | Pico_mcd->s68k_regs[3];
286 pixel_out = gfx.lut_prio[(reg >> 3) & 0x03][pixel_in][pixel_out];
288 /* write data to image buffer */
289 WRITE_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1, pixel_out);
291 /* check current pixel position */
292 if ((bufferIndex & 7) != 7)
299 /* next cell: increment image buffer offset by one column (minus 7 pixels) */
300 bufferIndex += gfx.bufferOffset;
303 /* increment pixel position */
309 void gfx_start(unsigned int base)
311 /* make sure 2M mode is enabled */
312 if (!(Pico_mcd->s68k_regs[3] & 0x04))
317 /* trace vector pointer */
318 gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + ((base << 2) & 0x3fff8));
320 /* stamps & stamp map size */
321 switch ((Pico_mcd->s68k_regs[0x58+1] >> 1) & 0x03)
324 gfx.dotMask = 0x07ffff; /* 256x256 dots/map */
325 gfx.stampShift = 11 + 4; /* 16x16 dots/stamps */
326 gfx.mapShift = 4; /* 16x16 stamps/map */
327 mask = 0x3fe00; /* 512 bytes/table */
331 gfx.dotMask = 0x07ffff; /* 256x256 dots/map */
332 gfx.stampShift = 11 + 5; /* 32x32 dots/stamps */
333 gfx.mapShift = 3; /* 8x8 stamps/map */
334 mask = 0x3ff80; /* 128 bytes/table */
338 gfx.dotMask = 0x7fffff; /* 4096*4096 dots/map */
339 gfx.stampShift = 11 + 4; /* 16x16 dots/stamps */
340 gfx.mapShift = 8; /* 256x256 stamps/map */
341 mask = 0x20000; /* 131072 bytes/table */
345 gfx.dotMask = 0x7fffff; /* 4096*4096 dots/map */
346 gfx.stampShift = 11 + 5; /* 32x32 dots/stamps */
347 gfx.mapShift = 7; /* 128x128 stamps/map */
348 mask = 0x38000; /* 32768 bytes/table */
352 /* stamp map table base address */
353 reg = (Pico_mcd->s68k_regs[0x5a] << 8) | Pico_mcd->s68k_regs[0x5b];
354 gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + ((reg << 2) & mask));
356 /* image buffer column offset (64 pixels/cell, minus 7 pixels to restart at cell beginning) */
357 gfx.bufferOffset = (((Pico_mcd->s68k_regs[0x5c+1] & 0x1f) + 1) << 6) - 7;
359 /* image buffer start index in dot units (2 pixels/byte) */
360 reg = (Pico_mcd->s68k_regs[0x5e] << 8) | Pico_mcd->s68k_regs[0x5f];
361 gfx.bufferStart = (reg << 3) & 0x7ffc0;
363 /* add image buffer horizontal dot offset */
364 gfx.bufferStart += (Pico_mcd->s68k_regs[0x60+1] & 0x3f);
366 /* reset GFX chip cycle counter */
367 //gfx.cycles = cycles;
369 /* update GFX chip timings (see AC3:Thunderhawk / Thunderstrike) */
370 //gfx.cyclesPerLine = 4 * 5 * scd.regs[0x62>>1].w;
372 /* start graphics operation */
373 Pico_mcd->s68k_regs[0x58] = 0x80;
379 /* PicoDrive specific */
380 #define UPDATE_CYCLES 20000
382 static void gfx_schedule(void)
387 w = (Pico_mcd->s68k_regs[0x62] << 8) | Pico_mcd->s68k_regs[0x63];
388 h = (Pico_mcd->s68k_regs[0x64] << 8) | Pico_mcd->s68k_regs[0x65];
391 if (cycles > UPDATE_CYCLES)
392 y_step = (UPDATE_CYCLES + 5 * w - 1) / (5 * w);
397 pcd_event_schedule_s68k(PCD_EVENT_GFX, 5 * w * y_step);
400 void gfx_update(unsigned int cycles)
402 int lines, lines_reg;
405 if (!(Pico_mcd->s68k_regs[0x58] & 0x80))
408 w = (Pico_mcd->s68k_regs[0x62] << 8) | Pico_mcd->s68k_regs[0x63];
409 lines = (Pico_mcd->s68k_regs[0x64] << 8) | Pico_mcd->s68k_regs[0x65];
410 lines_reg = lines - gfx.y_step;
412 if (lines_reg <= 0) {
413 Pico_mcd->s68k_regs[0x58] = 0;
414 Pico_mcd->s68k_regs[0x64] =
415 Pico_mcd->s68k_regs[0x65] = 0;
417 if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN1) {
418 elprintf(EL_INTS|EL_CD, "s68k: gfx_cd irq 1");
423 Pico_mcd->s68k_regs[0x64] = lines_reg >> 8;
424 Pico_mcd->s68k_regs[0x65] = lines_reg;
426 if (lines > gfx.y_step)
429 pcd_event_schedule(cycles, PCD_EVENT_GFX, 5 * w * lines);
432 if (PicoOpt & POPT_EN_MCD_GFX)
437 /* process dots to image buffer */
438 gfx_render(gfx.bufferStart, w);
440 /* increment image buffer start index for next line (8 pixels/line) */
441 gfx.bufferStart += 8;
446 // vim:shiftwidth=2:ts=2:expandtab