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
 46DECL_BITFIELD(GBAObjAttributesA, uint16_t);
 47DECL_BITS(GBAObjAttributesA, Y, 0, 8);
 48DECL_BIT(GBAObjAttributesA, Transformed, 8);
 49DECL_BIT(GBAObjAttributesA, Disable, 9);
 50DECL_BIT(GBAObjAttributesA, DoubleSize, 9);
 51DECL_BITS(GBAObjAttributesA, Mode, 10, 2);
 52DECL_BIT(GBAObjAttributesA, Mosaic, 12);
 53DECL_BIT(GBAObjAttributesA, 256Color, 13);
 54DECL_BITS(GBAObjAttributesA, Shape, 14, 2);
 55
 56
 57DECL_BITFIELD(GBAObjAttributesB, uint16_t);
 58DECL_BITS(GBAObjAttributesB, X, 0, 9);
 59DECL_BITS(GBAObjAttributesB, MatIndex, 9, 5);
 60DECL_BIT(GBAObjAttributesB, HFlip, 12);
 61DECL_BIT(GBAObjAttributesB, VFlip, 13);
 62DECL_BITS(GBAObjAttributesB, Size, 14, 2);
 63
 64DECL_BITFIELD(GBAObjAttributesC, uint16_t);
 65DECL_BITS(GBAObjAttributesC, Tile, 0, 10);
 66DECL_BITS(GBAObjAttributesC, Priority, 10, 2);
 67DECL_BITS(GBAObjAttributesC, Palette, 12, 4);
 68
 69struct GBAObj {
 70	GBAObjAttributesA a;
 71	GBAObjAttributesB b;
 72	GBAObjAttributesC c;
 73	uint16_t d;
 74};
 75
 76union GBAOAM {
 77	struct GBAObj obj[128];
 78
 79	struct GBAOAMMatrix {
 80		int16_t padding0[3];
 81		int16_t a;
 82		int16_t padding1[3];
 83		int16_t b;
 84		int16_t padding2[3];
 85		int16_t c;
 86		int16_t padding3[3];
 87		int16_t d;
 88	} mat[32];
 89
 90	uint16_t raw[512];
 91};
 92
 93#define GBA_TEXT_MAP_TILE(MAP) ((MAP) & 0x03FF)
 94#define GBA_TEXT_MAP_HFLIP(MAP) ((MAP) & 0x0400)
 95#define GBA_TEXT_MAP_VFLIP(MAP) ((MAP) & 0x0800)
 96#define GBA_TEXT_MAP_PALETTE(MAP) (((MAP) & 0xF000) >> 12)
 97
 98DECL_BITFIELD(GBARegisterDISPCNT, uint16_t);
 99DECL_BITS(GBARegisterDISPCNT, Mode, 0, 3);
100DECL_BIT(GBARegisterDISPCNT, Cgb, 3);
101DECL_BIT(GBARegisterDISPCNT, FrameSelect, 4);
102DECL_BIT(GBARegisterDISPCNT, HblankIntervalFree, 5);
103DECL_BIT(GBARegisterDISPCNT, ObjCharacterMapping, 6);
104DECL_BIT(GBARegisterDISPCNT, ForcedBlank, 7);
105DECL_BIT(GBARegisterDISPCNT, Bg0Enable, 8);
106DECL_BIT(GBARegisterDISPCNT, Bg1Enable, 9);
107DECL_BIT(GBARegisterDISPCNT, Bg2Enable, 10);
108DECL_BIT(GBARegisterDISPCNT, Bg3Enable, 11);
109DECL_BIT(GBARegisterDISPCNT, ObjEnable, 12);
110DECL_BIT(GBARegisterDISPCNT, Win0Enable, 13);
111DECL_BIT(GBARegisterDISPCNT, Win1Enable, 14);
112DECL_BIT(GBARegisterDISPCNT, ObjwinEnable, 15);
113
114DECL_BITFIELD(GBARegisterDISPSTAT, uint16_t);
115DECL_BIT(GBARegisterDISPSTAT, InVblank, 0);
116DECL_BIT(GBARegisterDISPSTAT, InHblank, 1);
117DECL_BIT(GBARegisterDISPSTAT, Vcounter, 2);
118DECL_BIT(GBARegisterDISPSTAT, VblankIRQ, 3);
119DECL_BIT(GBARegisterDISPSTAT, HblankIRQ, 4);
120DECL_BIT(GBARegisterDISPSTAT, VcounterIRQ, 5);
121DECL_BITS(GBARegisterDISPSTAT, VcountSetting, 8, 8);
122
123DECL_BITFIELD(GBARegisterBGCNT, uint16_t);
124DECL_BITS(GBARegisterBGCNT, Priority, 0, 2);
125DECL_BITS(GBARegisterBGCNT, CharBase, 2, 2);
126DECL_BIT(GBARegisterBGCNT, Mosaic, 6);
127DECL_BIT(GBARegisterBGCNT, 256Color, 7);
128DECL_BITS(GBARegisterBGCNT, ScreenBase, 8, 5);
129DECL_BIT(GBARegisterBGCNT, Overflow, 13);
130DECL_BITS(GBARegisterBGCNT, Size, 14, 2);
131
132struct GBAVideoRenderer {
133	void (*init)(struct GBAVideoRenderer* renderer);
134	void (*reset)(struct GBAVideoRenderer* renderer);
135	void (*deinit)(struct GBAVideoRenderer* renderer);
136
137	uint16_t (*writeVideoRegister)(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
138	void (*writePalette)(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
139	void (*writeOAM)(struct GBAVideoRenderer* renderer, uint32_t oam);
140	void (*drawScanline)(struct GBAVideoRenderer* renderer, int y);
141	void (*finishFrame)(struct GBAVideoRenderer* renderer);
142
143	void (*getPixels)(struct GBAVideoRenderer* renderer, unsigned* stride, void** pixels);
144	void (*putPixels)(struct GBAVideoRenderer* renderer, unsigned stride, void* pixels);
145
146	uint16_t* palette;
147	uint16_t* vram;
148	union GBAOAM* oam;
149};
150
151struct GBAVideo {
152	struct GBA* p;
153	struct GBAVideoRenderer* renderer;
154
155	GBARegisterDISPSTAT dispstat;
156
157	// VCOUNT
158	int vcount;
159
160	int32_t lastHblank;
161	int32_t nextHblank;
162	int32_t nextEvent;
163	int32_t eventDiff;
164
165	int32_t nextHblankIRQ;
166	int32_t nextVblankIRQ;
167	int32_t nextVcounterIRQ;
168
169	uint16_t palette[SIZE_PALETTE_RAM >> 1];
170	uint16_t* vram;
171	union GBAOAM oam;
172};
173
174void GBAVideoInit(struct GBAVideo* video);
175void GBAVideoReset(struct GBAVideo* video);
176void GBAVideoDeinit(struct GBAVideo* video);
177void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer);
178int32_t GBAVideoProcessEvents(struct GBAVideo* video, int32_t cycles);
179
180void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value);
181
182struct GBASerializedState;
183void GBAVideoSerialize(struct GBAVideo* video, struct GBASerializedState* state);
184void GBAVideoDeserialize(struct GBAVideo* video, struct GBASerializedState* state);
185
186#endif