src/gba/gba-video.c (view raw)
1#include "gba-video.h"
2
3#include "gba.h"
4#include "gba-io.h"
5#include "gba-rr.h"
6#include "gba-serialize.h"
7#include "gba-thread.h"
8
9#include "util/memory.h"
10
11static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer);
12static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer);
13static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer);
14static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
15static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
16static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam);
17static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y);
18static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer);
19static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, unsigned* stride, void** pixels);
20
21static struct GBAVideoRenderer dummyRenderer = {
22 .init = GBAVideoDummyRendererInit,
23 .reset = GBAVideoDummyRendererReset,
24 .deinit = GBAVideoDummyRendererDeinit,
25 .writeVideoRegister = GBAVideoDummyRendererWriteVideoRegister,
26 .writePalette = GBAVideoDummyRendererWritePalette,
27 .writeOAM = GBAVideoDummyRendererWriteOAM,
28 .drawScanline = GBAVideoDummyRendererDrawScanline,
29 .finishFrame = GBAVideoDummyRendererFinishFrame,
30 .getPixels = GBAVideoDummyRendererGetPixels
31};
32
33void GBAVideoInit(struct GBAVideo* video) {
34 video->renderer = &dummyRenderer;
35 video->vram = 0;
36}
37
38void GBAVideoReset(struct GBAVideo* video) {
39 video->dispstat = 0;
40 video->vcount = 0;
41
42 video->lastHblank = 0;
43 video->nextHblank = VIDEO_HDRAW_LENGTH;
44 video->nextEvent = video->nextHblank;
45 video->eventDiff = video->nextEvent;
46
47 video->nextHblankIRQ = 0;
48 video->nextVblankIRQ = 0;
49 video->nextVcounterIRQ = 0;
50
51 if (video->vram) {
52 mappedMemoryFree(video->vram, SIZE_VRAM);
53 }
54 video->vram = anonymousMemoryMap(SIZE_VRAM);
55 video->renderer->vram = video->vram;
56
57 int i;
58 for (i = 0; i < 128; ++i) {
59 video->oam.raw[i * 4] = 0x0200;
60 video->oam.raw[i * 4 + 1] = 0x0000;
61 video->oam.raw[i * 4 + 2] = 0x0000;
62 video->oam.raw[i * 4 + 3] = 0x0000;
63 }
64
65 video->renderer->deinit(video->renderer);
66 video->renderer->init(video->renderer);
67}
68
69void GBAVideoDeinit(struct GBAVideo* video) {
70 GBAVideoAssociateRenderer(video, &dummyRenderer);
71 mappedMemoryFree(video->vram, SIZE_VRAM);
72}
73
74void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer) {
75 video->renderer->deinit(video->renderer);
76 video->renderer = renderer;
77 renderer->palette = video->palette;
78 renderer->vram = video->vram;
79 renderer->oam = &video->oam;
80 video->renderer->init(video->renderer);
81}
82
83int32_t GBAVideoProcessEvents(struct GBAVideo* video, int32_t cycles) {
84 video->nextEvent -= cycles;
85 video->eventDiff += cycles;
86 if (video->nextEvent <= 0) {
87 int32_t lastEvent = video->nextEvent;
88 video->lastHblank -= video->eventDiff;
89 video->nextHblank -= video->eventDiff;
90 video->nextHblankIRQ -= video->eventDiff;
91 video->nextVcounterIRQ -= video->eventDiff;
92
93 if (GBARegisterDISPSTATIsInHblank(video->dispstat)) {
94 // End Hblank
95 video->dispstat = GBARegisterDISPSTATClearInHblank(video->dispstat);
96 video->nextEvent = video->nextHblank;
97
98 ++video->vcount;
99 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
100
101 switch (video->vcount) {
102 case VIDEO_VERTICAL_PIXELS:
103 video->dispstat = GBARegisterDISPSTATFillInVblank(video->dispstat);
104 if (GBASyncDrawingFrame(video->p->sync)) {
105 video->renderer->finishFrame(video->renderer);
106 }
107 video->nextVblankIRQ = video->nextEvent + VIDEO_TOTAL_LENGTH;
108 GBAMemoryRunVblankDMAs(video->p, lastEvent);
109 if (GBARegisterDISPSTATIsVblankIRQ(video->dispstat)) {
110 GBARaiseIRQ(video->p, IRQ_VBLANK);
111 }
112 GBASyncPostFrame(video->p->sync);
113 break;
114 case VIDEO_VERTICAL_TOTAL_PIXELS - 1:
115 if (video->p->rr) {
116 GBARRNextFrame(video->p->rr);
117 }
118 video->dispstat = GBARegisterDISPSTATClearInVblank(video->dispstat);
119 break;
120 case VIDEO_VERTICAL_TOTAL_PIXELS:
121 video->vcount = 0;
122 video->p->memory.io[REG_VCOUNT >> 1] = 0;
123 break;
124 }
125
126 if (video->vcount == GBARegisterDISPSTATGetVcountSetting(video->dispstat)) {
127 video->dispstat = GBARegisterDISPSTATFillVcounter(video->dispstat);
128 if (GBARegisterDISPSTATIsVcounterIRQ(video->dispstat)) {
129 GBARaiseIRQ(video->p, IRQ_VCOUNTER);
130 video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
131 }
132 } else {
133 video->dispstat = GBARegisterDISPSTATClearVcounter(video->dispstat);
134 }
135 } else {
136 // Begin Hblank
137 video->dispstat = GBARegisterDISPSTATFillInHblank(video->dispstat);
138 video->lastHblank = video->nextHblank;
139 video->nextEvent = video->lastHblank + VIDEO_HBLANK_LENGTH;
140 video->nextHblank = video->nextEvent + VIDEO_HDRAW_LENGTH;
141 video->nextHblankIRQ = video->nextHblank;
142
143 if (video->vcount < VIDEO_VERTICAL_PIXELS && GBASyncDrawingFrame(video->p->sync)) {
144 video->renderer->drawScanline(video->renderer, video->vcount);
145 }
146
147 if (video->vcount < VIDEO_VERTICAL_PIXELS) {
148 GBAMemoryRunHblankDMAs(video->p, lastEvent);
149 }
150 if (GBARegisterDISPSTATIsHblankIRQ(video->dispstat)) {
151 GBARaiseIRQ(video->p, IRQ_HBLANK);
152 }
153 }
154
155 video->eventDiff = 0;
156 }
157 video->p->memory.io[REG_DISPSTAT >> 1] &= 0xFFF8;
158 video->p->memory.io[REG_DISPSTAT >> 1] |= video->dispstat & 0x7;
159 return video->nextEvent;
160}
161
162void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value) {
163 video->dispstat &= 0x7;
164 video->dispstat |= value & 0xFFF8;
165
166 if (GBARegisterDISPSTATIsVcounterIRQ(video->dispstat)) {
167 // FIXME: this can be too late if we're in the middle of an Hblank
168 video->nextVcounterIRQ = video->nextHblank + VIDEO_HBLANK_LENGTH + (GBARegisterDISPSTATGetVcountSetting(video->dispstat) - video->vcount) * VIDEO_HORIZONTAL_LENGTH;
169 if (video->nextVcounterIRQ < video->nextEvent) {
170 video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
171 }
172 }
173}
174
175static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer) {
176 UNUSED(renderer);
177 // Nothing to do
178}
179
180static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer) {
181 UNUSED(renderer);
182 // Nothing to do
183}
184
185static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer) {
186 UNUSED(renderer);
187 // Nothing to do
188}
189
190static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
191 UNUSED(renderer);
192 UNUSED(address);
193 return value;
194}
195
196static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
197 UNUSED(renderer);
198 UNUSED(address);
199 UNUSED(value);
200 // Nothing to do
201}
202
203static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
204 UNUSED(renderer);
205 UNUSED(oam);
206 // Nothing to do
207}
208
209static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
210 UNUSED(renderer);
211 UNUSED(y);
212 // Nothing to do
213}
214
215static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer) {
216 UNUSED(renderer);
217 // Nothing to do
218}
219
220static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, unsigned* stride, void** pixels) {
221 UNUSED(renderer);
222 UNUSED(stride);
223 UNUSED(pixels);
224 // Nothing to do
225}
226
227
228void GBAVideoSerialize(struct GBAVideo* video, struct GBASerializedState* state) {
229 memcpy(state->vram, video->renderer->vram, SIZE_VRAM);
230 memcpy(state->oam, video->oam.raw, SIZE_OAM);
231 memcpy(state->pram, video->palette, SIZE_PALETTE_RAM);
232 state->io[REG_DISPSTAT >> 1] = video->dispstat;
233 state->video.nextEvent = video->nextEvent;
234 state->video.eventDiff = video->eventDiff;
235 state->video.lastHblank = video->lastHblank;
236 state->video.nextHblank = video->nextHblank;
237 state->video.nextHblankIRQ = video->nextHblankIRQ;
238 state->video.nextVblankIRQ = video->nextVblankIRQ;
239 state->video.nextVcounterIRQ = video->nextVcounterIRQ;
240}
241
242void GBAVideoDeserialize(struct GBAVideo* video, struct GBASerializedState* state) {
243 memcpy(video->renderer->vram, state->vram, SIZE_VRAM);
244 int i;
245 for (i = 0; i < SIZE_OAM; i += 2) {
246 GBAStore16(video->p->cpu, BASE_OAM | i, state->oam[i >> 1], 0);
247 }
248 for (i = 0; i < SIZE_PALETTE_RAM; i += 2) {
249 GBAStore16(video->p->cpu, BASE_PALETTE_RAM | i, state->pram[i >> 1], 0);
250 }
251 video->dispstat = state->io[REG_DISPSTAT >> 1];
252 video->nextEvent = state->video.nextEvent;
253 video->eventDiff = state->video.eventDiff;
254 video->lastHblank = state->video.lastHblank;
255 video->nextHblank = state->video.nextHblank;
256 video->nextHblankIRQ = state->video.nextHblankIRQ;
257 video->nextVblankIRQ = state->video.nextVblankIRQ;
258 video->nextVcounterIRQ = state->video.nextVcounterIRQ;
259 video->vcount = state->io[REG_VCOUNT >> 1];
260}