From bee6419eb0f4e1b64d31c10f5e99ae10c61951ea Mon Sep 17 00:00:00 2001 From: tangstad Date: Thu, 24 Nov 2005 21:44:49 +0000 Subject: [PATCH] Added sin/cos lookup tables and used fixed points to get nice rotational steering on the car (gas/brake with A/B). All the chasers rotate in the same direction as the car, but still stay in the same spot. --- gba/cartest/src/cartest.c | 136 +++++++++++++++++++++----------------- gba/cartest/src/sinlut.c | 89 +++++++++++++++++++++++++ gba/cartest/src/sinlut.h | 19 ++++++ 3 files changed, 184 insertions(+), 60 deletions(-) create mode 100644 gba/cartest/src/sinlut.c create mode 100644 gba/cartest/src/sinlut.h diff --git a/gba/cartest/src/cartest.c b/gba/cartest/src/cartest.c index 1bb1325..e518b4e 100644 --- a/gba/cartest/src/cartest.c +++ b/gba/cartest/src/cartest.c @@ -19,6 +19,19 @@ #include "car_pal_bin.h" #include "car_bin.h" #include "chaser_bin.h" +#include "sinlut.h" + +typedef s32 FIXED; // 32bit FIXED in 24.8 format +#define FIX_SHIFT 8 +#define INT2FIX(n) ((n)<>FIX_SHIFT) + + + +#define SIN_SIZE 512 +#define SIN_MASK (SIN_SIZE-1) +#define lut_sin(x) _sinLUT[x] +#define lut_cos(x) _sinLUT[(x + (SIN_SIZE>>2)) & SIN_MASK] //--------------------------------------------------------------------------------- // storage space for palette data @@ -33,6 +46,7 @@ OBJAFFINE *const oa_buffer = (OBJAFFINE*)oe_buffer; unsigned int frame; + //--------------------------------------------------------------------------------- void VblankInterrupt() //--------------------------------------------------------------------------------- @@ -82,79 +96,81 @@ int main(void) s32 base = (s32)(0.707106781 * 256); s32 one = 1 << 8; - car_aff->pa = 1 << 8; - car_aff->pb = 0; - car_aff->pc = 0;; - car_aff->pd = 1 << 8; - u8 i; for (i=0; ipa = base; - car_aff->pb = base; - car_aff->pc = -base; - car_aff->pd = base; - } else if ((KeysHeld() & KEY_RIGHT) && (KeysHeld() & KEY_DOWN)) { - car_aff->pa = -base; - car_aff->pb = base; - car_aff->pc = -base; - car_aff->pd = -base; - } else if ((KeysHeld() & KEY_LEFT) && (KeysHeld() & KEY_DOWN)) { - car_aff->pa = -base; - car_aff->pb = -base; - car_aff->pc = base; - car_aff->pd = -base; - } else if ((KeysHeld() & KEY_LEFT) && (KeysHeld() & KEY_UP)) { - car_aff->pa = base; - car_aff->pb = -base; - car_aff->pc = base; - car_aff->pd = base; - } else if (KeysHeld() & KEY_UP) { - car_aff->pa = 1 << 8; - car_aff->pb = 0; - car_aff->pc = 0;; - car_aff->pd = 1 << 8; - } else if (KeysHeld() & KEY_RIGHT) { - car_aff->pa = 0; - car_aff->pb = one; - car_aff->pc = -one; - car_aff->pd = 0; - } else if (KeysHeld() & KEY_DOWN) { - car_aff->pa = -one; - car_aff->pb = 0; - car_aff->pc = 0; - car_aff->pd = -one; + if (KeysHeld() & KEY_RIGHT) { + angle -= 8; } else if (KeysHeld() & KEY_LEFT) { - car_aff->pa = 0; - car_aff->pb = -one; - car_aff->pc = one; - car_aff->pd = 0; + angle += 8; + } + if (angle < 0) { + angle += 512; + } else if (angle >= 512) { + angle -= 512; + } + + if (KeysHeld() & KEY_A) { + if ((speed<30) && (speed>=0)) { + // slow speedup + speed += 1; + } else if (speed<0) { + // break if we're going backward + speed += 2; + } + } + if (KeysHeld() & KEY_B) { + if ((speed>=-5) && (speed<=0)) { + // slow speedup + speed -= 1; + } else if (speed>0) { + // break if we're going forward + speed -= 2; + } + } + // slow down if we're not doing anything + if (!(KeysHeld() & KEY_A) && !(KeysHeld() & KEY_B)) { + if (speed>0) { + speed -= 1; + } else if (speed<0) { + speed += 1; + } } - if (KeysHeld() & KEY_RIGHT) - x += 1; - else if (KeysHeld() & KEY_LEFT) - x -= 1; + int fspeed = speed >> 3; + + x -= fspeed*lut_sin(angle); + y -= fspeed*lut_cos(angle); - if (KeysHeld() & KEY_UP) - y -= 1; - else if (KeysHeld() & KEY_DOWN) - y += 1; + if (x>=INT2FIX(232)) { + x -= INT2FIX(256); + } else if (xattr1 = OBJ_SIZE(1) | OBJ_X(x); - car->attr0 = OBJ_256_COLOR | OBJ_DOUBLE | OBJ_ROT_SCALE_ON | OBJ_Y(y); + if (y>=INT2FIX(152)) { + y -= INT2FIX(176); + } else if (ypa = lut_cos(angle); + car_aff->pb = -lut_sin(angle); + car_aff->pc = lut_sin(angle); + car_aff->pd = lut_cos(angle); + + car->attr1 = OBJ_SIZE(1) | OBJ_X(FIX2INT(x)); + car->attr0 = OBJ_256_COLOR | OBJ_DOUBLE | OBJ_ROT_SCALE_ON | OBJ_Y(FIX2INT(y)); VBlankIntrWait(); CpuFastSet(oe_buffer, OAM, COPY32 | sizeof(oe_buffer)/4); diff --git a/gba/cartest/src/sinlut.c b/gba/cartest/src/sinlut.c new file mode 100644 index 0000000..68971f8 --- /dev/null +++ b/gba/cartest/src/sinlut.c @@ -0,0 +1,89 @@ +// ===================================================================== +// Look-Up Tables +// SIN: sin(x*pi/256) +// +// Exported by Cearn's excellut v0.9 +// (comments, kudos, flames to daytshen@hotmail.com) +// +// ===================================================================== + +#include "sinlut.h" + +// ----------------------------------------------------------------------- +// SIN: a 512 long LUT of 16bit values in 8.8 format +// sin(x*pi/256) +const signed short _sinLUT[512]= +{ + 0x0000,0x0003,0x0006,0x0009,0x000D,0x0010,0x0013,0x0016, + 0x0019,0x001C,0x001F,0x0022,0x0026,0x0029,0x002C,0x002F, + 0x0032,0x0035,0x0038,0x003B,0x003E,0x0041,0x0044,0x0047, + 0x004A,0x004D,0x0050,0x0053,0x0056,0x0059,0x005C,0x005F, + 0x0062,0x0065,0x0068,0x006B,0x006D,0x0070,0x0073,0x0076, + 0x0079,0x007B,0x007E,0x0081,0x0084,0x0086,0x0089,0x008C, + 0x008E,0x0091,0x0093,0x0096,0x0098,0x009B,0x009D,0x00A0, + 0x00A2,0x00A5,0x00A7,0x00AA,0x00AC,0x00AE,0x00B1,0x00B3, + + 0x00B5,0x00B7,0x00B9,0x00BC,0x00BE,0x00C0,0x00C2,0x00C4, + 0x00C6,0x00C8,0x00CA,0x00CC,0x00CE,0x00CF,0x00D1,0x00D3, + 0x00D5,0x00D7,0x00D8,0x00DA,0x00DC,0x00DD,0x00DF,0x00E0, + 0x00E2,0x00E3,0x00E5,0x00E6,0x00E7,0x00E9,0x00EA,0x00EB, + 0x00ED,0x00EE,0x00EF,0x00F0,0x00F1,0x00F2,0x00F3,0x00F4, + 0x00F5,0x00F6,0x00F7,0x00F8,0x00F8,0x00F9,0x00FA,0x00FA, + 0x00FB,0x00FC,0x00FC,0x00FD,0x00FD,0x00FE,0x00FE,0x00FE, + 0x00FF,0x00FF,0x00FF,0x0100,0x0100,0x0100,0x0100,0x0100, + + 0x0100,0x0100,0x0100,0x0100,0x0100,0x0100,0x00FF,0x00FF, + 0x00FF,0x00FE,0x00FE,0x00FE,0x00FD,0x00FD,0x00FC,0x00FC, + 0x00FB,0x00FA,0x00FA,0x00F9,0x00F8,0x00F8,0x00F7,0x00F6, + 0x00F5,0x00F4,0x00F3,0x00F2,0x00F1,0x00F0,0x00EF,0x00EE, + 0x00ED,0x00EB,0x00EA,0x00E9,0x00E7,0x00E6,0x00E5,0x00E3, + 0x00E2,0x00E0,0x00DF,0x00DD,0x00DC,0x00DA,0x00D8,0x00D7, + 0x00D5,0x00D3,0x00D1,0x00CF,0x00CE,0x00CC,0x00CA,0x00C8, + 0x00C6,0x00C4,0x00C2,0x00C0,0x00BE,0x00BC,0x00B9,0x00B7, + + 0x00B5,0x00B3,0x00B1,0x00AE,0x00AC,0x00AA,0x00A7,0x00A5, + 0x00A2,0x00A0,0x009D,0x009B,0x0098,0x0096,0x0093,0x0091, + 0x008E,0x008C,0x0089,0x0086,0x0084,0x0081,0x007E,0x007B, + 0x0079,0x0076,0x0073,0x0070,0x006D,0x006B,0x0068,0x0065, + 0x0062,0x005F,0x005C,0x0059,0x0056,0x0053,0x0050,0x004D, + 0x004A,0x0047,0x0044,0x0041,0x003E,0x003B,0x0038,0x0035, + 0x0032,0x002F,0x002C,0x0029,0x0026,0x0022,0x001F,0x001C, + 0x0019,0x0016,0x0013,0x0010,0x000D,0x0009,0x0006,0x0003, + + 0x0000,0xFFFD,0xFFFA,0xFFF7,0xFFF3,0xFFF0,0xFFED,0xFFEA, + 0xFFE7,0xFFE4,0xFFE1,0xFFDE,0xFFDA,0xFFD7,0xFFD4,0xFFD1, + 0xFFCE,0xFFCB,0xFFC8,0xFFC5,0xFFC2,0xFFBF,0xFFBC,0xFFB9, + 0xFFB6,0xFFB3,0xFFB0,0xFFAD,0xFFAA,0xFFA7,0xFFA4,0xFFA1, + 0xFF9E,0xFF9B,0xFF98,0xFF95,0xFF93,0xFF90,0xFF8D,0xFF8A, + 0xFF87,0xFF85,0xFF82,0xFF7F,0xFF7C,0xFF7A,0xFF77,0xFF74, + 0xFF72,0xFF6F,0xFF6D,0xFF6A,0xFF68,0xFF65,0xFF63,0xFF60, + 0xFF5E,0xFF5B,0xFF59,0xFF56,0xFF54,0xFF52,0xFF4F,0xFF4D, + + 0xFF4B,0xFF49,0xFF47,0xFF44,0xFF42,0xFF40,0xFF3E,0xFF3C, + 0xFF3A,0xFF38,0xFF36,0xFF34,0xFF32,0xFF31,0xFF2F,0xFF2D, + 0xFF2B,0xFF29,0xFF28,0xFF26,0xFF24,0xFF23,0xFF21,0xFF20, + 0xFF1E,0xFF1D,0xFF1B,0xFF1A,0xFF19,0xFF17,0xFF16,0xFF15, + 0xFF13,0xFF12,0xFF11,0xFF10,0xFF0F,0xFF0E,0xFF0D,0xFF0C, + 0xFF0B,0xFF0A,0xFF09,0xFF08,0xFF08,0xFF07,0xFF06,0xFF06, + 0xFF05,0xFF04,0xFF04,0xFF03,0xFF03,0xFF02,0xFF02,0xFF02, + 0xFF01,0xFF01,0xFF01,0xFF00,0xFF00,0xFF00,0xFF00,0xFF00, + + 0xFF00,0xFF00,0xFF00,0xFF00,0xFF00,0xFF00,0xFF01,0xFF01, + 0xFF01,0xFF02,0xFF02,0xFF02,0xFF03,0xFF03,0xFF04,0xFF04, + 0xFF05,0xFF06,0xFF06,0xFF07,0xFF08,0xFF08,0xFF09,0xFF0A, + 0xFF0B,0xFF0C,0xFF0D,0xFF0E,0xFF0F,0xFF10,0xFF11,0xFF12, + 0xFF13,0xFF15,0xFF16,0xFF17,0xFF19,0xFF1A,0xFF1B,0xFF1D, + 0xFF1E,0xFF20,0xFF21,0xFF23,0xFF24,0xFF26,0xFF28,0xFF29, + 0xFF2B,0xFF2D,0xFF2F,0xFF31,0xFF32,0xFF34,0xFF36,0xFF38, + 0xFF3A,0xFF3C,0xFF3E,0xFF40,0xFF42,0xFF44,0xFF47,0xFF49, + + 0xFF4B,0xFF4D,0xFF4F,0xFF52,0xFF54,0xFF56,0xFF59,0xFF5B, + 0xFF5E,0xFF60,0xFF63,0xFF65,0xFF68,0xFF6A,0xFF6D,0xFF6F, + 0xFF72,0xFF74,0xFF77,0xFF7A,0xFF7C,0xFF7F,0xFF82,0xFF85, + 0xFF87,0xFF8A,0xFF8D,0xFF90,0xFF93,0xFF95,0xFF98,0xFF9B, + 0xFF9E,0xFFA1,0xFFA4,0xFFA7,0xFFAA,0xFFAD,0xFFB0,0xFFB3, + 0xFFB6,0xFFB9,0xFFBC,0xFFBF,0xFFC2,0xFFC5,0xFFC8,0xFFCB, + 0xFFCE,0xFFD1,0xFFD4,0xFFD7,0xFFDA,0xFFDE,0xFFE1,0xFFE4, + 0xFFE7,0xFFEA,0xFFED,0xFFF0,0xFFF3,0xFFF7,0xFFFA,0xFFFD, +}; + diff --git a/gba/cartest/src/sinlut.h b/gba/cartest/src/sinlut.h new file mode 100644 index 0000000..230b473 --- /dev/null +++ b/gba/cartest/src/sinlut.h @@ -0,0 +1,19 @@ +// ===================================================================== +// +// Exported by Cearn's excellut v0.9 +// (comments, kudos, flames to daytshen@hotmail.com) +// +// ===================================================================== + +#ifndef SINLUT_H +#define SINLUT_H + +// === LUT SIZES === +#define SIN_SIZE 512 + + +// === LUT DECLARATIONS === +extern const signed short _sinLUT[]; + + +#endif // SINLUT_H