path: root/src/util.c

#include "global.h"
#include "util.h"

const u32 gBitTable[] =
{
    1 << 0,
    1 << 1,
    1 << 2,
    1 << 3,
    1 << 4,
    1 << 5,
    1 << 6,
    1 << 7,
    1 << 8,
    1 << 9,
    1 << 10,
    1 << 11,
    1 << 12,
    1 << 13,
    1 << 14,
    1 << 15,
    1 << 16,
    1 << 17,
    1 << 18,
    1 << 19,
    1 << 20,
    1 << 21,
    1 << 22,
    1 << 23,
    1 << 24,
    1 << 25,
    1 << 26,
    1 << 27,
    1 << 28,
    1 << 29,
    1 << 30,
    1 << 31,
};

static const struct SpriteTemplate gInvisibleSpriteTemplate =
{
    .tileTag = 0,
    .paletteTag = 0,
    .oam = &gDummyOamData,
    .anims = gDummySpriteAnimTable,
    .images = NULL,
    .affineAnims = gDummySpriteAffineAnimTable,
    .callback = SpriteCallbackDummy,
};

static const u8 gSpriteDimensions[3][4][2] =
{
    // square
    {
        {1, 1},
        {2, 2},
        {4, 4},
        {8, 8},
    },

    // horizontal rectangle
    {
        {2, 1},
        {4, 1},
        {4, 2},
        {8, 4},
    },

    // vertical rectangle
    {
        {1, 2},
        {1, 4},
        {2, 4},
        {4, 8},
    },
};

static const u16 gCrc16Table[] =
{
    0x0000, 0x1189, 0x2312, 0x329B, 0x4624, 0x57AD, 0x6536, 0x74BF,
    0x8C48, 0x9DC1, 0xAF5A, 0xBED3, 0xCA6C, 0xDBE5, 0xE97E, 0xF8F7,
    0x1081, 0x0108, 0x3393, 0x221A, 0x56A5, 0x472C, 0x75B7, 0x643E,
    0x9CC9, 0x8D40, 0xBFDB, 0xAE52, 0xDAED, 0xCB64, 0xF9FF, 0xE876,
    0x2102, 0x308B, 0x0210, 0x1399, 0x6726, 0x76AF, 0x4434, 0x55BD,
    0xAD4A, 0xBCC3, 0x8E58, 0x9FD1, 0xEB6E, 0xFAE7, 0xC87C, 0xD9F5,
    0x3183, 0x200A, 0x1291, 0x0318, 0x77A7, 0x662E, 0x54B5, 0x453C,
    0xBDCB, 0xAC42, 0x9ED9, 0x8F50, 0xFBEF, 0xEA66, 0xD8FD, 0xC974,
    0x4204, 0x538D, 0x6116, 0x709F, 0x0420, 0x15A9, 0x2732, 0x36BB,
    0xCE4C, 0xDFC5, 0xED5E, 0xFCD7, 0x8868, 0x99E1, 0xAB7A, 0xBAF3,
    0x5285, 0x430C, 0x7197, 0x601E, 0x14A1, 0x0528, 0x37B3, 0x263A,
    0xDECD, 0xCF44, 0xFDDF, 0xEC56, 0x98E9, 0x8960, 0xBBFB, 0xAA72,
    0x6306, 0x728F, 0x4014, 0x519D, 0x2522, 0x34AB, 0x0630, 0x17B9,
    0xEF4E, 0xFEC7, 0xCC5C, 0xDDD5, 0xA96A, 0xB8E3, 0x8A78, 0x9BF1,
    0x7387, 0x620E, 0x5095, 0x411C, 0x35A3, 0x242A, 0x16B1, 0x0738,
    0xFFCF, 0xEE46, 0xDCDD, 0xCD54, 0xB9EB, 0xA862, 0x9AF9, 0x8B70,
    0x8408, 0x9581, 0xA71A, 0xB693, 0xC22C, 0xD3A5, 0xE13E, 0xF0B7,
    0x0840, 0x19C9, 0x2B52, 0x3ADB, 0x4E64, 0x5FED, 0x6D76, 0x7CFF,
    0x9489, 0x8500, 0xB79B, 0xA612, 0xD2AD, 0xC324, 0xF1BF, 0xE036,
    0x18C1, 0x0948, 0x3BD3, 0x2A5A, 0x5EE5, 0x4F6C, 0x7DF7, 0x6C7E,
    0xA50A, 0xB483, 0x8618, 0x9791, 0xE32E, 0xF2A7, 0xC03C, 0xD1B5,
    0x2942, 0x38CB, 0x0A50, 0x1BD9, 0x6F66, 0x7EEF, 0x4C74, 0x5DFD,
    0xB58B, 0xA402, 0x9699, 0x8710, 0xF3AF, 0xE226, 0xD0BD, 0xC134,
    0x39C3, 0x284A, 0x1AD1, 0x0B58, 0x7FE7, 0x6E6E, 0x5CF5, 0x4D7C,
    0xC60C, 0xD785, 0xE51E, 0xF497, 0x8028, 0x91A1, 0xA33A, 0xB2B3,
    0x4A44, 0x5BCD, 0x6956, 0x78DF, 0x0C60, 0x1DE9, 0x2F72, 0x3EFB,
    0xD68D, 0xC704, 0xF59F, 0xE416, 0x90A9, 0x8120, 0xB3BB, 0xA232,
    0x5AC5, 0x4B4C, 0x79D7, 0x685E, 0x1CE1, 0x0D68, 0x3FF3, 0x2E7A,
    0xE70E, 0xF687, 0xC41C, 0xD595, 0xA12A, 0xB0A3, 0x8238, 0x93B1,
    0x6B46, 0x7ACF, 0x4854, 0x59DD, 0x2D62, 0x3CEB, 0x0E70, 0x1FF9,
    0xF78F, 0xE606, 0xD49D, 0xC514, 0xB1AB, 0xA022, 0x92B9, 0x8330,
    0x7BC7, 0x6A4E, 0x58D5, 0x495C, 0x3DE3, 0x2C6A, 0x1EF1, 0x0F78,
};

const u8 gMiscBlank_Gfx[] = INCBIN_U8("graphics/interface/blank.4bpp");


u8 CreateInvisibleSpriteWithCallback(void (*callback)(struct Sprite *))
{
    u8 sprite = CreateSprite(&gInvisibleSpriteTemplate, 248, 168, 14);
    gSprites[sprite].invisible = TRUE;
    gSprites[sprite].callback = callback;
    return sprite;
}

void StoreWordInTwoHalfwords(u16 *h, u32 w)
{
    h[0] = (u16)(w);
    h[1] = (u16)(w >> 16);
}

void LoadWordFromTwoHalfwords(u16 *h, u32 *w)
{
    *w = h[0] | (s16)h[1] << 16;
}

void SetBgAffineStruct(struct BgAffineSrcData *src, u32 texX, u32 texY, s16 scrX, s16 scrY, s16 sx, s16 sy, u16 alpha)
{
    src->texX = texX;
    src->texY = texY;
    src->scrX = scrX;
    src->scrY = scrY;
    src->sx = sx;
    src->sy = sy;
    src->alpha = alpha;
}

void DoBgAffineSet(struct BgAffineDstData *dest, u32 texX, u32 texY, s16 scrX, s16 scrY, s16 sx, s16 sy, u16 alpha)
{
    struct BgAffineSrcData src;

    SetBgAffineStruct(&src, texX, texY, scrX, scrY, sx, sy, alpha);
    BgAffineSet(&src, dest, 1);
}

#ifdef NONMATCHING

// Functionally equivalent.
// Only the two yflip loops don't match.
void CopySpriteTiles(u8 shape, u8 size, u8 *tiles, u16 *tilemap, u8 *output)
{
    u8 x, y;
    s8 i, j;
    u8 xflip[32];
    u8 h = gSpriteDimensions[shape][size][1];
    u8 w = gSpriteDimensions[shape][size][0];

    for (y = 0; y < h; y++)
    {
        int filler = 32 - w;

        for (x = 0; x < w; x++)
        {
            int tile = (*tilemap & 0x3ff) * 32;
            int attr = *tilemap & 0xc00;

            if (attr == 0)
            {
                void *src = tiles + tile;
                void *dest = output;
                int length = 32;
                DmaCopy32(3, src, dest, length);
            }
            else if (attr == 0x800)  // yflip
            {
                for (i = 0; i < 8; i++)
                {
                    void *src = tiles;
                    void *dest = output;
                    int length = 4;
                    // this is likely wrong, but makes it closer to matching
                    src += tile + (7 - i) * 4;
                    dest += i * 4;
                    DmaCopy32(3, src, dest, length);
                }
            }
            else  // xflip
            {
                for (i = 0; i < 8; i++)
                {
                    for (j = 0; j < 4; j++)
                    {
                        u8 i2 = i * 4;
                        xflip[i2 + (3-j)] = (tiles[tile + i2 + j] & 0xf) << 4;
                        xflip[i2 + (3-j)] |= tiles[tile + i2 + j] >> 4;
                    }
                }
                if (*tilemap & 0x800)  // yflip
                {
                    for (i = 0; i < 8; i++)
                    {
                        void *src = xflip + (7-i) * 4;
                        void *dest = output + i*4;
                        int length = 4;
                        DmaCopy32(3, src, dest, length);
                    }
                }
                else
                {
                    void *src = xflip;
                    void *dest = output;
                    int length = 32;
                    DmaCopy32(3, src, dest, length);
                }
            }
            tilemap++;
            output += 32;
        }
        tilemap += filler;
    }
}

#else

__attribute__((naked)) void CopySpriteTiles(u8 shape, u8 size, u8 *tiles, u16 *tilemap, u8 *output)
{
    asm("\n"
    "    .syntax unified\n"
    "    push {r4-r7,lr}\n"
    "    mov r7, r10\n"
    "    mov r6, r9\n"
    "    mov r5, r8\n"
    "    push {r5-r7}\n"
    "    sub sp, 0x3C\n"
    "    str r2, [sp, 0x20]\n"
    "    adds r4, r3, 0\n"
    "    ldr r7, [sp, 0x5C]\n"
    "    lsls r0, 24\n"
    "    lsls r1, 24\n"
    "    ldr r2, _08041008 @ =gSpriteDimensions\n"
    "    lsrs r1, 23\n"
    "    lsrs r0, 21\n"
    "    adds r1, r0\n"
    "    adds r0, r2, 0x1\n"
    "    adds r0, r1, r0\n"
    "    ldrb r0, [r0]\n"
    "    str r0, [sp, 0x24]\n"
    "    adds r1, r2\n"
    "    ldrb r1, [r1]\n"
    "    str r1, [sp, 0x28]\n"
    "    movs r1, 0\n"
    "    cmp r1, r0\n"
    "    bcc _08040FB4\n"
    "    b _08041136\n"
    "_08040FB4:\n"
    "    movs r0, 0x20\n"
    "    ldr r2, [sp, 0x28]\n"
    "    subs r0, r2\n"
    "    lsls r0, 1\n"
    "    str r0, [sp, 0x2C]\n"
    "_08040FBE:\n"
    "    movs r2, 0\n"
    "    adds r1, 0x1\n"
    "    str r1, [sp, 0x34]\n"
    "    ldr r3, [sp, 0x28]\n"
    "    cmp r2, r3\n"
    "    bcc _08040FCC\n"
    "    b _08041124\n"
    "_08040FCC:\n"
    "    ldr r0, _0804100C @ =0x040000d4\n"
    "    mov r8, r0\n"
    "_08040FD0:\n"
    "    ldrh r1, [r4]\n"
    "    ldr r0, _08041010 @ =0x000003ff\n"
    "    ands r0, r1\n"
    "    lsls r0, 5\n"
    "    mov r12, r0\n"
    "    movs r0, 0xC0\n"
    "    lsls r0, 4\n"
    "    ands r0, r1\n"
    "    mov r3, sp\n"
    "    strh r1, [r3, 0x38]\n"
    "    cmp r0, 0\n"
    "    bne _08041018\n"
    "    ldr r0, [sp, 0x20]\n"
    "    add r0, r12\n"
    "    mov r1, r8\n"
    "    str r0, [r1]\n"
    "    str r7, [r1, 0x4]\n"
    "    ldr r3, _08041014 @ =0x84000008\n"
    "    str r3, [r1, 0x8]\n"
    "    ldr r0, [r1, 0x8]\n"
    "    adds r4, 0x2\n"
    "    str r4, [sp, 0x30]\n"
    "    adds r7, 0x20\n"
    "    mov r10, r7\n"
    "    adds r2, 0x1\n"
    "    mov r9, r2\n"
    "    b _08041112\n"
    "    .align 2, 0\n"
    "_08041008: .4byte gSpriteDimensions\n"
    "_0804100C: .4byte 0x040000d4\n"
    "_08041010: .4byte 0x000003ff\n"
    "_08041014: .4byte 0x84000008\n"
    "_08041018:\n"
    "    movs r1, 0x80\n"
    "    lsls r1, 4\n"
    "    cmp r0, r1\n"
    "    bne _08041068\n"
    "    movs r3, 0\n"
    "    adds r4, 0x2\n"
    "    str r4, [sp, 0x30]\n"
    "    movs r0, 0x20\n"
    "    adds r0, r7\n"
    "    mov r10, r0\n"
    "    adds r2, 0x1\n"
    "    mov r9, r2\n"
    "    ldr r4, _08041060 @ =0x040000d4\n"
    "    ldr r6, _08041064 @ =0x84000001\n"
    "    movs r5, 0x7\n"
    "_08041036:\n"
    "    lsls r2, r3, 24\n"
    "    asrs r2, 24\n"
    "    subs r0, r5, r2\n"
    "    lsls r0, 2\n"
    "    add r0, r12\n"
    "    ldr r1, [sp, 0x20]\n"
    "    adds r0, r1, r0\n"
    "    lsls r1, r2, 2\n"
    "    adds r1, r7, r1\n"
    "    str r0, [r4]\n"
    "    str r1, [r4, 0x4]\n"
    "    str r6, [r4, 0x8]\n"
    "    ldr r0, [r4, 0x8]\n"
    "    adds r2, 0x1\n"
    "    lsls r2, 24\n"
    "    lsrs r3, r2, 24\n"
    "    asrs r2, 24\n"
    "    cmp r2, 0x7\n"
    "    ble _08041036\n"
    "    b _08041112\n"
    "    .align 2, 0\n"
    "_08041060: .4byte 0x040000d4\n"
    "_08041064: .4byte 0x84000001\n"
    "_08041068:\n"
    "    movs r3, 0\n"
    "    adds r4, 0x2\n"
    "    str r4, [sp, 0x30]\n"
    "    movs r0, 0x20\n"
    "    adds r0, r7\n"
    "    mov r10, r0\n"
    "    adds r2, 0x1\n"
    "    mov r9, r2\n"
    "_08041078:\n"
    "    movs r2, 0\n"
    "    lsls r4, r3, 24\n"
    "    lsls r0, r4, 2\n"
    "    lsrs r0, 24\n"
    "    adds r6, r0, 0x3\n"
    "    mov r1, r12\n"
    "    adds r5, r1, r0\n"
    "_08041086:\n"
    "    lsls r1, r2, 24\n"
    "    asrs r1, 24\n"
    "    subs r0, r6, r1\n"
    "    mov r2, sp\n"
    "    adds r3, r2, r0\n"
    "    adds r0, r5, r1\n"
    "    ldr r2, [sp, 0x20]\n"
    "    adds r0, r2, r0\n"
    "    ldrb r2, [r0]\n"
    "    movs r0, 0xF\n"
    "    ands r0, r2\n"
    "    lsls r0, 4\n"
    "    lsrs r2, 4\n"
    "    orrs r0, r2\n"
    "    strb r0, [r3]\n"
    "    adds r1, 0x1\n"
    "    lsls r1, 24\n"
    "    lsrs r2, r1, 24\n"
    "    asrs r1, 24\n"
    "    cmp r1, 0x3\n"
    "    ble _08041086\n"
    "    movs r3, 0x80\n"
    "    lsls r3, 17\n"
    "    adds r0, r4, r3\n"
    "    lsrs r3, r0, 24\n"
    "    asrs r0, 24\n"
    "    cmp r0, 0x7\n"
    "    ble _08041078\n"
    "    movs r0, 0x80\n"
    "    lsls r0, 4\n"
    "    mov r1, sp\n"
    "    ldrh r1, [r1, 0x38]\n"
    "    ands r0, r1\n"
    "    cmp r0, 0\n"
    "    beq _08041104\n"
    "    movs r3, 0\n"
    "    ldr r4, _080410FC @ =0x040000d4\n"
    "    ldr r6, _08041100 @ =0x84000001\n"
    "    movs r5, 0x7\n"
    "_080410D4:\n"
    "    lsls r1, r3, 24\n"
    "    asrs r1, 24\n"
    "    subs r0, r5, r1\n"
    "    lsls r0, 2\n"
    "    mov r3, sp\n"
    "    adds r2, r3, r0\n"
    "    lsls r0, r1, 2\n"
    "    adds r0, r7, r0\n"
    "    str r2, [r4]\n"
    "    str r0, [r4, 0x4]\n"
    "    str r6, [r4, 0x8]\n"
    "    ldr r0, [r4, 0x8]\n"
    "    adds r1, 0x1\n"
    "    lsls r1, 24\n"
    "    lsrs r3, r1, 24\n"
    "    asrs r1, 24\n"
    "    cmp r1, 0x7\n"
    "    ble _080410D4\n"
    "    b _08041112\n"
    "    .align 2, 0\n"
    "_080410FC: .4byte 0x040000d4\n"
    "_08041100: .4byte 0x84000001\n"
    "_08041104:\n"
    "    mov r0, sp\n"
    "    mov r1, r8\n"
    "    str r0, [r1]\n"
    "    str r7, [r1, 0x4]\n"
    "    ldr r2, _08041148 @ =0x84000008\n"
    "    str r2, [r1, 0x8]\n"
    "    ldr r0, [r1, 0x8]\n"
    "_08041112:\n"
    "    ldr r4, [sp, 0x30]\n"
    "    mov r7, r10\n"
    "    mov r3, r9\n"
    "    lsls r0, r3, 24\n"
    "    lsrs r2, r0, 24\n"
    "    ldr r0, [sp, 0x28]\n"
    "    cmp r2, r0\n"
    "    bcs _08041124\n"
    "    b _08040FD0\n"
    "_08041124:\n"
    "    ldr r1, [sp, 0x2C]\n"
    "    adds r4, r1\n"
    "    ldr r2, [sp, 0x34]\n"
    "    lsls r0, r2, 24\n"
    "    lsrs r1, r0, 24\n"
    "    ldr r3, [sp, 0x24]\n"
    "    cmp r1, r3\n"
    "    bcs _08041136\n"
    "    b _08040FBE\n"
    "_08041136:\n"
    "    add sp, 0x3C\n"
    "    pop {r3-r5}\n"
    "    mov r8, r3\n"
    "    mov r9, r4\n"
    "    mov r10, r5\n"
    "    pop {r4-r7}\n"
    "    pop {r0}\n"
    "    bx r0\n"
    "    .align 2, 0\n"
    "_08041148: .4byte 0x84000008\n"
    "    .syntax divided\n"
    );
}

#endif

int CountTrailingZeroBits(u32 value)
{
    u8 i;

    for (i = 0; i < 32; i++)
    {
        if ((value & 1) == 0)
            value >>= 1;
        else
            return i;
    }
    return 0;
}

u16 CalcCRC16(u8 *data, int length)
{
    u16 i, j;
    u16 crc = 0x1121;

    for (i = 0; i < length; i++)
    {
        crc ^= data[i];
        for (j = 0; j < 8; j++)
        {
            if (crc & 1)
                crc = (crc >> 1) ^ 0x8408;
            else
                crc >>= 1;
        }
    }
    return ~crc;
}

u16 CalcCRC16WithTable(u8 *data, int length)
{
    u16 i;
    u16 crc = 0x1121;
    u8 byte;

    for (i = 0; i < length; i++)
    {
        byte = crc >> 8;
        crc ^= data[i];
        crc = byte ^ gCrc16Table[(u8)crc];
    }
    return ~crc;
}