e53f0499 |
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 | ****************************************************************************************/ |
a93a80de |
38 | #include "../pico_int.h" |
39 | #include "genplus_macros.h" |
e53f0499 |
40 | |
41 | typedef struct |
42 | { |
a93a80de |
43 | //uint32 cycles; /* current cycles count for graphics operation */ |
44 | //uint32 cyclesPerLine; /* current graphics operation timings */ |
e53f0499 |
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 */ |
a93a80de |
52 | uint32 y_step; /* pico: render line step */ |
e53f0499 |
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 */ |
56 | } gfx_t; |
57 | |
58 | static gfx_t gfx; |
59 | |
a93a80de |
60 | static void gfx_schedule(void); |
61 | |
e53f0499 |
62 | /***************************************************************/ |
63 | /* Rotation / Scaling operation (2M Mode) */ |
64 | /***************************************************************/ |
65 | |
66 | void gfx_init(void) |
67 | { |
68 | int i, j; |
e53f0499 |
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<0x100; i++) |
75 | { |
76 | for (j=0; j<0x100; j++) |
77 | { |
78 | /* normal */ |
79 | gfx.lut_prio[0][i][j] = j; |
80 | /* underwrite */ |
81 | gfx.lut_prio[1][i][j] = ((i & 0x0f) ? (i & 0x0f) : (j & 0x0f)) | ((i & 0xf0) ? (i & 0xf0) : (j & 0xf0)); |
82 | /* overwrite */ |
83 | gfx.lut_prio[2][i][j] = ((j & 0x0f) ? (j & 0x0f) : (i & 0x0f)) | ((j & 0xf0) ? (j & 0xf0) : (i & 0xf0)); |
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 | |
e53f0499 |
130 | int gfx_context_save(uint8 *state) |
131 | { |
132 | uint32 tmp32; |
133 | int bufferptr = 0; |
134 | |
a93a80de |
135 | //save_param(&gfx.cycles, sizeof(gfx.cycles)); |
136 | //save_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine)); |
e53f0499 |
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 | |
a93a80de |
143 | tmp32 = (uint8 *)(gfx.tracePtr) - Pico_mcd->word_ram2M; |
e53f0499 |
144 | save_param(&tmp32, 4); |
145 | |
a93a80de |
146 | tmp32 = (uint8 *)(gfx.mapPtr) - Pico_mcd->word_ram2M; |
e53f0499 |
147 | save_param(&tmp32, 4); |
148 | |
a93a80de |
149 | save_param(&gfx.y_step, sizeof(gfx.y_step)); |
150 | |
e53f0499 |
151 | return bufferptr; |
152 | } |
153 | |
a93a80de |
154 | int gfx_context_load(const uint8 *state) |
e53f0499 |
155 | { |
156 | uint32 tmp32; |
157 | int bufferptr = 0; |
158 | |
a93a80de |
159 | //load_param(&gfx.cycles, sizeof(gfx.cycles)); |
160 | //load_param(&gfx.cyclesPerLine, sizeof(gfx.cyclesPerLine)); |
e53f0499 |
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); |
a93a80de |
168 | gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32); |
e53f0499 |
169 | |
170 | load_param(&tmp32, 4); |
a93a80de |
171 | gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + tmp32); |
172 | |
173 | load_param(&gfx.y_step, sizeof(gfx.y_step)); |
e53f0499 |
174 | |
175 | return bufferptr; |
176 | } |
177 | |
a93a80de |
178 | static void gfx_render(uint32 bufferIndex, uint32 width) |
e53f0499 |
179 | { |
180 | uint8 pixel_in, pixel_out; |
181 | uint16 stamp_data; |
182 | uint32 stamp_index; |
a93a80de |
183 | uint32 reg; |
e53f0499 |
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 | /* process all dots */ |
194 | while (width--) |
195 | { |
196 | /* check if stamp map is repeated */ |
a93a80de |
197 | if (Pico_mcd->s68k_regs[0x58+1] & 0x01) |
e53f0499 |
198 | { |
199 | /* stamp map range */ |
200 | xpos &= gfx.dotMask; |
201 | ypos &= gfx.dotMask; |
202 | } |
203 | else |
204 | { |
205 | /* 24-bit range */ |
206 | xpos &= 0xffffff; |
207 | ypos &= 0xffffff; |
208 | } |
209 | |
210 | /* check if pixel is outside stamp map */ |
211 | if ((xpos | ypos) & ~gfx.dotMask) |
212 | { |
213 | /* force pixel output to 0 */ |
214 | pixel_out = 0x00; |
215 | } |
216 | else |
217 | { |
218 | /* read stamp map table data */ |
219 | stamp_data = gfx.mapPtr[(xpos >> gfx.stampShift) | ((ypos >> gfx.stampShift) << gfx.mapShift)]; |
220 | |
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; |
228 | |
229 | if (stamp_index) |
230 | { |
231 | /* extract HFLIP & ROTATION bits */ |
232 | stamp_data = (stamp_data >> 13) & 7; |
233 | |
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 */ |
a93a80de |
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; |
e53f0499 |
243 | |
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)]; |
250 | |
251 | /* read pixel pair (2 pixels/byte) */ |
a93a80de |
252 | pixel_out = READ_BYTE(Pico_mcd->word_ram2M, stamp_index >> 1); |
e53f0499 |
253 | |
254 | /* extract left or rigth pixel */ |
255 | if (stamp_index & 1) |
256 | { |
257 | pixel_out &= 0x0f; |
258 | } |
259 | else |
260 | { |
261 | pixel_out >>= 4; |
262 | } |
263 | } |
264 | else |
265 | { |
266 | /* stamp 0 is not used: force pixel output to 0 */ |
267 | pixel_out = 0x00; |
268 | } |
269 | } |
270 | |
271 | /* read out paired pixel data */ |
a93a80de |
272 | pixel_in = READ_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1); |
e53f0499 |
273 | |
274 | /* update left or rigth pixel */ |
275 | if (bufferIndex & 1) |
276 | { |
277 | pixel_out |= (pixel_in & 0xf0); |
278 | } |
279 | else |
280 | { |
281 | pixel_out = (pixel_out << 4) | (pixel_in & 0x0f); |
282 | } |
283 | |
284 | /* priority mode write */ |
a93a80de |
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]; |
e53f0499 |
287 | |
288 | /* write data to image buffer */ |
a93a80de |
289 | WRITE_BYTE(Pico_mcd->word_ram2M, bufferIndex >> 1, pixel_out); |
e53f0499 |
290 | |
291 | /* check current pixel position */ |
292 | if ((bufferIndex & 7) != 7) |
293 | { |
294 | /* next pixel */ |
295 | bufferIndex++; |
296 | } |
297 | else |
298 | { |
299 | /* next cell: increment image buffer offset by one column (minus 7 pixels) */ |
300 | bufferIndex += gfx.bufferOffset; |
301 | } |
302 | |
303 | /* increment pixel position */ |
304 | xpos += xoffset; |
305 | ypos += yoffset; |
306 | } |
307 | } |
308 | |
a93a80de |
309 | void gfx_start(unsigned int base) |
e53f0499 |
310 | { |
311 | /* make sure 2M mode is enabled */ |
a93a80de |
312 | if (!(Pico_mcd->s68k_regs[3] & 0x04)) |
e53f0499 |
313 | { |
314 | uint32 mask; |
a93a80de |
315 | uint32 reg; |
e53f0499 |
316 | |
317 | /* trace vector pointer */ |
a93a80de |
318 | gfx.tracePtr = (uint16 *)(Pico_mcd->word_ram2M + ((base << 2) & 0x3fff8)); |
e53f0499 |
319 | |
320 | /* stamps & stamp map size */ |
a93a80de |
321 | switch ((Pico_mcd->s68k_regs[0x58+1] >> 1) & 0x03) |
e53f0499 |
322 | { |
323 | case 0: |
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 */ |
328 | break; |
329 | |
330 | case 1: |
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 */ |
335 | break; |
336 | |
337 | case 2: |
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 */ |
342 | break; |
343 | |
344 | case 3: |
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 */ |
349 | break; |
350 | } |
351 | |
352 | /* stamp map table base address */ |
a93a80de |
353 | reg = (Pico_mcd->s68k_regs[0x5a] << 8) | Pico_mcd->s68k_regs[0x5b]; |
354 | gfx.mapPtr = (uint16 *)(Pico_mcd->word_ram2M + ((reg << 2) & mask)); |
e53f0499 |
355 | |
356 | /* image buffer column offset (64 pixels/cell, minus 7 pixels to restart at cell beginning) */ |
a93a80de |
357 | gfx.bufferOffset = (((Pico_mcd->s68k_regs[0x5c+1] & 0x1f) + 1) << 6) - 7; |
e53f0499 |
358 | |
359 | /* image buffer start index in dot units (2 pixels/byte) */ |
a93a80de |
360 | reg = (Pico_mcd->s68k_regs[0x5e] << 8) | Pico_mcd->s68k_regs[0x5f]; |
361 | gfx.bufferStart = (reg << 3) & 0x7ffc0; |
e53f0499 |
362 | |
363 | /* add image buffer horizontal dot offset */ |
a93a80de |
364 | gfx.bufferStart += (Pico_mcd->s68k_regs[0x60+1] & 0x3f); |
e53f0499 |
365 | |
366 | /* reset GFX chip cycle counter */ |
a93a80de |
367 | //gfx.cycles = cycles; |
e53f0499 |
368 | |
369 | /* update GFX chip timings (see AC3:Thunderhawk / Thunderstrike) */ |
a93a80de |
370 | //gfx.cyclesPerLine = 4 * 5 * scd.regs[0x62>>1].w; |
e53f0499 |
371 | |
372 | /* start graphics operation */ |
a93a80de |
373 | Pico_mcd->s68k_regs[0x58] = 0x80; |
374 | |
375 | gfx_schedule(); |
e53f0499 |
376 | } |
377 | } |
378 | |
a93a80de |
379 | /* PicoDrive specific */ |
380 | #define UPDATE_CYCLES 20000 |
381 | |
382 | static void gfx_schedule(void) |
e53f0499 |
383 | { |
a93a80de |
384 | int w, h, cycles; |
385 | int y_step; |
e53f0499 |
386 | |
a93a80de |
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]; |
e53f0499 |
389 | |
a93a80de |
390 | cycles = 5 * w * h; |
391 | if (cycles > UPDATE_CYCLES) |
392 | y_step = (UPDATE_CYCLES + 5 * w - 1) / (5 * w); |
393 | else |
394 | y_step = h; |
e53f0499 |
395 | |
a93a80de |
396 | gfx.y_step = y_step; |
397 | pcd_event_schedule_s68k(PCD_EVENT_GFX, 5 * w * y_step); |
398 | } |
e53f0499 |
399 | |
a93a80de |
400 | void gfx_update(unsigned int cycles) |
401 | { |
402 | int lines, lines_reg; |
403 | int w; |
e53f0499 |
404 | |
a93a80de |
405 | if (!(Pico_mcd->s68k_regs[0x58] & 0x80)) |
406 | return; |
e53f0499 |
407 | |
a93a80de |
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; |
411 | |
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; |
416 | |
417 | if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN1) { |
418 | elprintf(EL_INTS|EL_CD, "s68k: gfx_cd irq 1"); |
419 | SekInterruptS68k(1); |
e53f0499 |
420 | } |
a93a80de |
421 | } |
422 | else { |
423 | Pico_mcd->s68k_regs[0x64] = lines_reg >> 8; |
424 | Pico_mcd->s68k_regs[0x65] = lines_reg; |
425 | |
426 | if (lines > gfx.y_step) |
427 | lines = gfx.y_step; |
428 | |
429 | pcd_event_schedule(cycles, PCD_EVENT_GFX, 5 * w * lines); |
430 | } |
e53f0499 |
431 | |
a93a80de |
432 | if (PicoOpt & POPT_EN_MCD_GFX) |
433 | { |
e53f0499 |
434 | /* render lines */ |
435 | while (lines--) |
436 | { |
437 | /* process dots to image buffer */ |
a93a80de |
438 | gfx_render(gfx.bufferStart, w); |
e53f0499 |
439 | |
440 | /* increment image buffer start index for next line (8 pixels/line) */ |
441 | gfx.bufferStart += 8; |
442 | } |
443 | } |
444 | } |
a93a80de |
445 | |
446 | // vim:shiftwidth=2:ts=2:expandtab |