forked from Mirror/GodMode9
76 lines
2.8 KiB
C
76 lines
2.8 KiB
C
#include "nds.h"
|
|
#include "vff.h"
|
|
|
|
#define CRC16_TABVAL 0x0000, 0xCC01, 0xD801, 0x1400, 0xF001, 0x3C00, 0x2800, 0xE401, 0xA001, 0x6C00, 0x7800, 0xB401, 0x5000, 0x9C01, 0x8801, 0x4400
|
|
|
|
// see: https://github.com/TASVideos/desmume/blob/master/desmume/src/bios.cpp#L1070tions
|
|
u16 crc16_quick(const void* src, u32 len) {
|
|
const u16 tabval[] = { CRC16_TABVAL };
|
|
u16* data = (u16*) src;
|
|
u16 crc = 0xFFFF;
|
|
|
|
for (len >>= 1; len; len--) {
|
|
u16 curr = *(data++);
|
|
for (u32 i = 0; i < 4; i++) {
|
|
u16 tval = tabval[crc&0xF];
|
|
crc >>= 4;
|
|
crc ^= tval;
|
|
tval = tabval[(curr >> (4*i))&0xF];
|
|
crc ^= tval;
|
|
}
|
|
}
|
|
|
|
return crc;
|
|
}
|
|
|
|
u32 ValidateTwlHeader(TwlHeader* twl) {
|
|
if (twl->logo_crc != NDS_LOGO_CRC16) return 1;
|
|
return (crc16_quick(twl->logo, sizeof(twl->logo)) == NDS_LOGO_CRC16) ? 0 : 1;
|
|
}
|
|
|
|
u32 LoadTwlIconData(const char* path, TwlIconData* icon) {
|
|
u8 ntr_header[0x200]; // we only need the NTR header (ignore TWL stuff)
|
|
TwlHeader* twl = (TwlHeader*) ntr_header;
|
|
UINT br;
|
|
if ((fvx_qread(path, ntr_header, 0, 0x200, &br) != FR_OK) || (br != 0x200) ||
|
|
(ValidateTwlHeader(twl) != 0))
|
|
return 1;
|
|
// we also don't need anything beyond the v0x0001 icon, so ignore this, too
|
|
if ((fvx_qread(path, icon, twl->icon_offset, TWLICON_SIZE_DATA(0x0001), &br) != FR_OK) || (br != TWLICON_SIZE_DATA(0x0001)) ||
|
|
(!TWLICON_SIZE_DATA(icon->version)) || (crc16_quick(((u8*) icon) + 0x20, TWLICON_SIZE_DATA(0x0001) - 0x20) != icon->crc_0x0020_0x0840))
|
|
return 1;
|
|
icon->version = 0x0001; // just to be safe
|
|
return 0;
|
|
}
|
|
|
|
// TWL title is max 128(+1) chars long
|
|
u32 GetTwlTitle(char* desc, const TwlIconData* twl_icon) {
|
|
const u16* title = twl_icon->title_eng; // english title
|
|
memset(desc, 0, TWLICON_SIZE_DESC + 1);
|
|
for (u32 i = 0; i < TWLICON_SIZE_DESC; i++) desc[i] = title[i];
|
|
return 0;
|
|
}
|
|
|
|
// TWL icon: 32x32 pixel, 8x8 tiles
|
|
u32 GetTwlIcon(u8* icon, const TwlIconData* twl_icon) {
|
|
const u32 h = TWLICON_DIM_ICON; // fixed size
|
|
const u32 w = TWLICON_DIM_ICON; // fixed size
|
|
u16* palette = twl_icon->palette;
|
|
u8* pix4 = (u8*) twl_icon->icon;
|
|
for (u32 y = 0; y < h; y += 8) {
|
|
for (u32 x = 0; x < w; x += 8) {
|
|
for (u32 i = 0; i < 8*8; i++) {
|
|
u32 ix = x + (i & 0x7);
|
|
u32 iy = y + (i >> 3);
|
|
u16 pix555 = palette[((i%2) ? (*pix4 >> 4) : *pix4) & 0xF];
|
|
u8* pix888 = icon + ((iy * w) + ix) * 3;
|
|
*(pix888++) = ((pix555 >> 10) & 0x1F) << 3; // B
|
|
*(pix888++) = ((pix555 >> 5) & 0x1F) << 3; // G
|
|
*(pix888++) = ((pix555 >> 0) & 0x1F) << 3; // R
|
|
if (i % 2) pix4++;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|