1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
|
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include "jag_video.h"
#include "render.h"
enum {
VMODE_CRY,
VMODE_RGB24,
VMODE_DIRECT16,
VMODE_RGB16,
VMODE_VARIABLE
};
#define BIT_TBGEN 1
char *vmode_names[] = {
"CRY",
"RGB24",
"RGB16",
"DIRECT16",
"VARIABLE"
};
static uint8_t cry_red[9][16] = {
{0, 34, 68, 102, 135, 169, 203, 237, 255, 255, 255, 255, 255, 255, 255, 255},
{0, 34, 68, 102, 135, 169, 203, 230, 247, 255, 255, 255, 255, 255, 255, 255},
{0, 34, 68, 102, 135, 170, 183, 197, 214, 235, 255, 255, 255, 255, 255, 255},
{0, 34, 68, 102, 130, 141, 153, 164, 181, 204, 227, 249, 255, 255, 255, 255},
{0, 34, 68, 95, 104, 113, 122, 131, 148, 173, 198, 223, 248, 255, 255, 255},
{0, 34, 64, 71, 78, 85, 91, 98, 115, 143, 170, 197, 224, 252, 255, 255},
{0, 34, 43, 47, 52, 56, 61, 65, 82, 112, 141, 171, 200, 230, 255, 255},
{0, 19, 21, 23, 26, 28, 30, 32, 49, 81, 113, 145, 177, 208, 240, 255},
{0, 0, 0, 0, 0, 0, 0, 0, 17, 51, 85, 119, 153, 187, 221, 255}
};
static uint8_t cry_green[16][8] = {
{0, 0, 0, 0, 0, 0, 0, 0},
{17, 19, 21, 23, 26, 28, 30, 32},
{34, 38, 43, 47, 52, 56, 61, 65},
{51, 57, 64, 71, 78, 85, 91, 98},
{68, 77, 86, 95, 104, 113, 122, 131},
{85, 96, 107, 119, 130, 141, 153, 164},
{102, 115, 129, 142, 156, 170, 183, 197},
{119, 134, 150, 166, 182, 198, 214, 230},
{136, 154, 172, 190, 208, 226, 244, 255},
{153, 173, 193, 214, 234, 255, 255, 255},
{170, 192, 215, 238, 255, 255, 255, 255},
{187, 211, 236, 255, 255, 255, 255, 255},
{204, 231, 255, 255, 255, 255, 255, 255},
{221, 250, 255, 255, 255, 255, 255, 255},
{238, 255, 255, 255, 255, 255, 255, 255},
{255, 255, 255, 255, 255, 255, 255, 255},
};
static uint32_t table_cry[0x10000];
static uint32_t table_rgb[0x10000];
static uint32_t table_variable[0x10000];
static uint32_t cry_to_rgb(uint16_t cry)
{
uint32_t y = cry & 0xFF;
if (y) {
uint8_t c = cry >> 12;
uint8_t r = cry >> 8 & 0xF;
uint32_t red = cry_red[c < 7 ? 0 : c - 7][r];
uint32_t green = cry_green[c][r < 8 ? r : 15 - r];
uint32_t blue = cry_red[c < 7 ? 0 : c - 7][15-r];
red = red * 255 / y;
blue = blue * 255 / y;
green = green * 255 / y;
return render_map_color(red, green, blue);
} else {
return render_map_color(0, 0, 0);
}
}
static uint32_t rgb16_to_rgb(uint16_t rgb)
{
return render_map_color(
rgb >> 8 & 0xF8,
rgb << 2 & 0xFC,
rgb >> 4 & 0xF8
);
}
jag_video *jag_video_init(void)
{
static uint8_t table_init_done = 0;
if (!table_init_done) {
for (int i = 0; i < 0x10000; i++)
{
table_cry[i] = cry_to_rgb(i);
table_rgb[i] = rgb16_to_rgb(i);
table_variable[i] = i & 1 ? rgb16_to_rgb(i & 0xFFFE) : cry_to_rgb(i);
}
table_init_done = 1;
}
return calloc(1, sizeof(jag_video));
}
static void copy_16(uint32_t *dst, uint32_t len, uint16_t *linebuffer, uint32_t *table)
{
for (; len; len--, dst++, linebuffer++)
{
*dst = table[*linebuffer];
}
}
static void copy_linebuffer(jag_video *context, uint16_t *linebuffer)
{
if (!context->output) {
return;
}
uint32_t *dst = context->output;
uint32_t len;
if (context->regs[VID_HCOUNT] == context->regs[VID_HDISP_BEGIN1]) {
if (
context->regs[VID_HDISP_BEGIN2] == context->regs[VID_HDISP_BEGIN1]
|| context->regs[VID_HDISP_BEGIN2] > (context->regs[VID_HPERIOD] | 0x400)
) {
//only one line buffer per line, so copy the previous line in its entirety
len = context->regs[VID_HDISP_END] - 0x400 + context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN1] + 2;
} else {
//copy the second half of the previous line
if (context->regs[VID_HDISP_BEGIN2] & 0x400) {
//BEGIN2 is after the HCOUNT jump
dst += context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN1]
+ context->regs[VID_HDISP_BEGIN2] - 0x400 + 1;
len = context->regs[VID_HDISP_END] - context->regs[VID_HDISP_BEGIN2] + 1;
} else {
//BEGIN2 is before the HCOUNT jump
dst += context->regs[VID_HDISP_BEGIN2] - context->regs[VID_HDISP_BEGIN1];
len = context->regs[VID_HDISP_END] + context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN2] + 2;
}
}
context->output += context->output_pitch / sizeof(uint32_t);
} else {
//copy the first half of the current line
if (context->regs[VID_HDISP_BEGIN2] & 0x400) {
//BEGIN2 is after the HCOUNT jump
len = context->regs[VID_HDISP_BEGIN2] - 0x400 + context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN1] + 1;
} else {
//BEGIN2 is before the HCOUNT jump
len = context->regs[VID_HDISP_BEGIN2] - context->regs[VID_HDISP_BEGIN1];
}
}
len /= context->pclock_div;
switch (context->mode)
{
case VMODE_CRY:
copy_16(dst, len, linebuffer, table_cry);
break;
case VMODE_RGB24:
//TODO: Implement me
break;
case VMODE_DIRECT16:
//TODO: Implement this once I better understand what would happen on hardware with composite output
break;
case VMODE_RGB16:
copy_16(dst, len, linebuffer, table_rgb);
break;
case VMODE_VARIABLE:
copy_16(dst, len, linebuffer, table_variable);
break;
}
}
void jag_video_run(jag_video *context, uint32_t target_cycle)
{
if (context->regs[VID_VMODE] & BIT_TBGEN) {
while (context->cycles < target_cycle)
{
//TODO: Optimize this to not actually increment one step at a time
if (
(
context->regs[VID_HCOUNT] == context->regs[VID_HDISP_BEGIN1]
|| context->regs[VID_HCOUNT] == context->regs[VID_HDISP_BEGIN2]
)
&& context->regs[VID_VCOUNT] >= context->regs[VID_VDISP_BEGIN]
&& context->regs[VID_VCOUNT] < context->regs[VID_VDISP_END]
) {
//swap linebuffers, render linebuffer to framebuffer and kick off object processor
if (context->write_line_buffer == context->line_buffer_a) {
context->write_line_buffer = context->line_buffer_b;
copy_linebuffer(context, context->line_buffer_a);
} else {
context->write_line_buffer = context->line_buffer_a;
copy_linebuffer(context, context->line_buffer_b);
}
//clear new write line buffer with background color
for (int i = 0; i < LINEBUFFER_WORDS; i++)
{
context->write_line_buffer[i] = context->regs[VID_BGCOLOR];
}
//TODO: kick off object processor
}
if (
!context->output
&& context->regs[VID_VCOUNT] == context->regs[VID_VDISP_BEGIN]
&& context->regs[VID_HCOUNT] == context->regs[VID_HDISP_BEGIN1]
) {
context->output = render_get_framebuffer(FRAMEBUFFER_ODD, &context->output_pitch);
} else if (context->output && context->regs[VID_VCOUNT] >= context->regs[VID_VDISP_END]) {
int width = (context->regs[VID_HPERIOD] - context->regs[VID_HDISP_BEGIN1]
+ context->regs[VID_HDISP_END] - 1024 + 2) / context->pclock_div;
render_framebuffer_updated(FRAMEBUFFER_ODD, width);
context->output = NULL;
}
if ((context->regs[VID_HCOUNT] & 0x3FF) == context->regs[VID_HPERIOD]) {
//reset bottom 10 bits to zero, flip the 11th bit which represents which half of the line we're on
context->regs[VID_HCOUNT] = (context->regs[VID_HCOUNT] & 0x400) ^ 0x400;
//increment half-line counter
if (context->regs[VID_VCOUNT] == context->regs[VID_VPERIOD]) {
context->regs[VID_VCOUNT] = 0;
} else {
context->regs[VID_VCOUNT]++;
}
} else {
context->regs[VID_HCOUNT]++;
}
context->cycles++;
}
} else {
context->cycles = target_cycle;
}
}
static uint8_t is_reg_writeable(uint32_t address)
{
return address < VID_HLPEN || address >= VID_OBJLIST1;
}
void jag_video_reg_write(jag_video *context, uint32_t address, uint16_t value)
{
uint32_t reg = (address >> 1 & 0x7F) - 2;
if (reg < JAG_VIDEO_REGS && is_reg_writeable(reg)) {
context->regs[reg] = value;
if (reg == VID_VMODE) {
context->pclock_div = (value >> 9 & 7) + 1;
context->pclock_counter = 0;
if (value & 0x10) {
context->mode = VMODE_VARIABLE;
} else {
context->mode = value >> 1 & 3;
}
printf("Mode %s, pixel clock divider: %d, time base generation: %s\n", vmode_names[context->mode], context->pclock_div, value & BIT_TBGEN ? "enabled" : "disabled");
}
switch (reg)
{
case VID_OBJLIST1:
printf("Object List Pointer 1: %X\n", value);
break;
case VID_OBJLIST2:
printf("Object List Pointer 2: %X\n", value);
break;
case VID_HPERIOD:
printf("Horizontal period: %d\n", value & 0x3FF);
break;
case VID_HBLANK_BEGIN:
printf("horizontal blanking begin: %d\n", value & 0x7FF);
break;
case VID_HBLANK_END:
printf("horizontal blanking end: %d\n", value & 0x7FF);
break;
case VID_HSYNC:
printf("horizontal sync start: %d\n", value & 0x7FF);
break;
case VID_HDISP_BEGIN1:
printf("horizontal display begin 1: %d\n", value & 0x7FF);
break;
case VID_HDISP_BEGIN2:
printf("horizontal display begin 2: %d\n", value & 0x7FF);
break;
case VID_HDISP_END:
printf("horizontal display end: %d\n", value & 0x7FF);
break;
case VID_VPERIOD:
printf("Vertical period: %d\n", value & 0x7FF);
break;
case VID_VBLANK_BEGIN:
printf("vertical blanking begin: %d\n", value & 0x7FF);
break;
case VID_VBLANK_END:
printf("vertical blanking end: %d\n", value & 0x7FF);
break;
case VID_VSYNC:
printf("vertical sync start: %d\n", value & 0x7FF);
break;
case VID_VDISP_BEGIN:
printf("vertical display begin: %d\n", value & 0x7FF);
break;
case VID_VDISP_END:
printf("vertical display end: %d\n", value & 0x7FF);
break;
}
} else {
fprintf(stderr, "Write to invalid video/object processor register %X:%X\n", address, value);
}
}
|
