1#ifndef GBA_VIDEO_H
  2#define GBA_VIDEO_H
  3
  4#include "common.h"
  5
  6#include "gba-memory.h"
  7
  8#ifdef COLOR_16_BIT
  9#define BYTES_PER_PIXEL 2
 10#else
 11#define BYTES_PER_PIXEL 4
 12#endif
 13
 14enum {
 15	VIDEO_CYCLES_PER_PIXEL = 4,
 16
 17	VIDEO_HORIZONTAL_PIXELS = 240,
 18	VIDEO_HBLANK_PIXELS = 68,
 19	VIDEO_HDRAW_LENGTH = 1006,
 20	VIDEO_HBLANK_LENGTH = 226,
 21	VIDEO_HORIZONTAL_LENGTH = 1232,
 22
 23	VIDEO_VERTICAL_PIXELS = 160,
 24	VIDEO_VBLANK_PIXELS = 68,
 25	VIDEO_VERTICAL_TOTAL_PIXELS = 228,
 26
 27	VIDEO_TOTAL_LENGTH = 280896,
 28
 29	REG_DISPSTAT_MASK = 0xFF38,
 30
 31	BASE_TILE = 0x00010000
 32};
 33
 34enum ObjMode {
 35	OBJ_MODE_NORMAL = 0,
 36	OBJ_MODE_SEMITRANSPARENT = 1,
 37	OBJ_MODE_OBJWIN = 2
 38};
 39
 40enum ObjShape {
 41	OBJ_SHAPE_SQUARE = 0,
 42	OBJ_SHAPE_HORIZONTAL = 1,
 43	OBJ_SHAPE_VERTICAL = 2
 44};
 45
 46struct GBAObj {
 47	unsigned y : 8;
 48	unsigned transformed : 1;
 49	unsigned disable : 1;
 50	enum ObjMode mode : 2;
 51	unsigned mosaic : 1;
 52	unsigned multipalette : 1;
 53	enum ObjShape shape : 2;
 54
 55	int x : 9;
 56	int : 3;
 57	unsigned hflip : 1;
 58	unsigned vflip : 1;
 59	unsigned size : 2;
 60
 61	unsigned tile : 10;
 62	unsigned priority : 2;
 63	unsigned palette : 4;
 64
 65	int : 16;
 66};
 67
 68struct GBATransformedObj {
 69	unsigned y : 8;
 70	unsigned transformed : 1;
 71	unsigned doublesize : 1;
 72	enum ObjMode mode : 2;
 73	unsigned mosaic : 1;
 74	unsigned multipalette : 1;
 75	enum ObjShape shape : 2;
 76
 77	int x : 9;
 78	unsigned matIndex : 5;
 79	unsigned size : 2;
 80
 81	unsigned tile : 10;
 82	unsigned priority : 2;
 83	unsigned palette : 4;
 84
 85	int : 16;
 86};
 87
 88union GBAOAM {
 89	struct GBAObj obj[128];
 90	struct GBATransformedObj tobj[128];
 91
 92	struct GBAOAMMatrix {
 93		int : 16;
 94		int : 16;
 95		int : 16;
 96		int a : 16;
 97		int : 16;
 98		int : 16;
 99		int : 16;
100		int b : 16;
101		int : 16;
102		int : 16;
103		int : 16;
104		int c : 16;
105		int : 16;
106		int : 16;
107		int : 16;
108		int d : 16;
109	} mat[32];
110
111	uint16_t raw[512];
112};
113
114#define GBA_TEXT_MAP_TILE(MAP) ((MAP) & 0x03FF)
115#define GBA_TEXT_MAP_HFLIP(MAP) ((MAP) & 0x0400)
116#define GBA_TEXT_MAP_VFLIP(MAP) ((MAP) & 0x0800)
117#define GBA_TEXT_MAP_PALETTE(MAP) (((MAP) & 0xF000) >> 12)
118
119DECL_BITFIELD(GBARegisterDISPCNT, uint16_t);
120DECL_BITS(GBARegisterDISPCNT, Mode, 0, 3);
121DECL_BIT(GBARegisterDISPCNT, Cgb, 3);
122DECL_BIT(GBARegisterDISPCNT, FrameSelect, 4);
123DECL_BIT(GBARegisterDISPCNT, HblankIntervalFree, 5);
124DECL_BIT(GBARegisterDISPCNT, ObjCharacterMapping, 6);
125DECL_BIT(GBARegisterDISPCNT, ForcedBlank, 7);
126DECL_BIT(GBARegisterDISPCNT, Bg0Enable, 8);
127DECL_BIT(GBARegisterDISPCNT, Bg1Enable, 9);
128DECL_BIT(GBARegisterDISPCNT, Bg2Enable, 10);
129DECL_BIT(GBARegisterDISPCNT, Bg3Enable, 11);
130DECL_BIT(GBARegisterDISPCNT, ObjEnable, 12);
131DECL_BIT(GBARegisterDISPCNT, Win0Enable, 13);
132DECL_BIT(GBARegisterDISPCNT, Win1Enable, 14);
133DECL_BIT(GBARegisterDISPCNT, ObjwinEnable, 15);
134
135DECL_BITFIELD(GBARegisterDISPSTAT, uint16_t);
136DECL_BIT(GBARegisterDISPSTAT, InVblank, 0);
137DECL_BIT(GBARegisterDISPSTAT, InHblank, 1);
138DECL_BIT(GBARegisterDISPSTAT, Vcounter, 2);
139DECL_BIT(GBARegisterDISPSTAT, VblankIRQ, 3);
140DECL_BIT(GBARegisterDISPSTAT, HblankIRQ, 4);
141DECL_BIT(GBARegisterDISPSTAT, VcounterIRQ, 5);
142DECL_BITS(GBARegisterDISPSTAT, VcountSetting, 8, 8);
143
144DECL_BITFIELD(GBARegisterBGCNT, uint16_t);
145DECL_BITS(GBARegisterBGCNT, Priority, 0, 2);
146DECL_BITS(GBARegisterBGCNT, CharBase, 2, 2);
147DECL_BIT(GBARegisterBGCNT, Mosaic, 6);
148DECL_BIT(GBARegisterBGCNT, 256Color, 7);
149DECL_BITS(GBARegisterBGCNT, ScreenBase, 8, 5);
150DECL_BIT(GBARegisterBGCNT, Overflow, 13);
151DECL_BITS(GBARegisterBGCNT, Size, 14, 2);
152
153struct GBAVideoRenderer {
154	void (*init)(struct GBAVideoRenderer* renderer);
155	void (*reset)(struct GBAVideoRenderer* renderer);
156	void (*deinit)(struct GBAVideoRenderer* renderer);
157
158	uint16_t (*writeVideoRegister)(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
159	void (*writePalette)(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
160	void (*writeOAM)(struct GBAVideoRenderer* renderer, uint32_t oam);
161	void (*drawScanline)(struct GBAVideoRenderer* renderer, int y);
162	void (*finishFrame)(struct GBAVideoRenderer* renderer);
163
164	void (*getPixels)(struct GBAVideoRenderer* renderer, unsigned* stride, void** pixels);
165	void (*putPixels)(struct GBAVideoRenderer* renderer, unsigned stride, void* pixels);
166
167	uint16_t* palette;
168	uint16_t* vram;
169	union GBAOAM* oam;
170};
171
172struct GBAVideo {
173	struct GBA* p;
174	struct GBAVideoRenderer* renderer;
175
176	GBARegisterDISPSTAT dispstat;
177
178	// VCOUNT
179	int vcount;
180
181	int32_t lastHblank;
182	int32_t nextHblank;
183	int32_t nextEvent;
184	int32_t eventDiff;
185
186	int32_t nextHblankIRQ;
187	int32_t nextVblankIRQ;
188	int32_t nextVcounterIRQ;
189
190	uint16_t palette[SIZE_PALETTE_RAM >> 1];
191	uint16_t* vram;
192	union GBAOAM oam;
193};
194
195void GBAVideoInit(struct GBAVideo* video);
196void GBAVideoReset(struct GBAVideo* video);
197void GBAVideoDeinit(struct GBAVideo* video);
198void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer);
199int32_t GBAVideoProcessEvents(struct GBAVideo* video, int32_t cycles);
200
201void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value);
202
203struct GBASerializedState;
204void GBAVideoSerialize(struct GBAVideo* video, struct GBASerializedState* state);
205void GBAVideoDeserialize(struct GBAVideo* video, struct GBASerializedState* state);
206
207#endif