GLideN64/src/convert.h

#ifndef CONVERT_H
#define CONVERT_H

#include "Types.h"

const volatile unsigned char Five2Eight[32] =
{
	  0, // 00000 = 00000000
	  8, // 00001 = 00001000
	 16, // 00010 = 00010000
	 25, // 00011 = 00011001
	 33, // 00100 = 00100001
	 41, // 00101 = 00101001
	 49, // 00110 = 00110001
	 58, // 00111 = 00111010
	 66, // 01000 = 01000010
	 74, // 01001 = 01001010
	 82, // 01010 = 01010010
	 90, // 01011 = 01011010
	 99, // 01100 = 01100011
	107, // 01101 = 01101011
	115, // 01110 = 01110011
	123, // 01111 = 01111011
	132, // 10000 = 10000100
	140, // 10001 = 10001100
	148, // 10010 = 10010100
	156, // 10011 = 10011100
	165, // 10100 = 10100101
	173, // 10101 = 10101101
	181, // 10110 = 10110101
	189, // 10111 = 10111101
	197, // 11000 = 11000101
	206, // 11001 = 11001110
	214, // 11010 = 11010110
	222, // 11011 = 11011110
	230, // 11100 = 11100110
	239, // 11101 = 11101111
	247, // 11110 = 11110111
	255  // 11111 = 11111111
};

const volatile unsigned char Four2Eight[16] =
{
	  0, // 0000 = 00000000
	 17, // 0001 = 00010001
	 34, // 0010 = 00100010
	 51, // 0011 = 00110011
	 68, // 0100 = 01000100
	 85, // 0101 = 01010101
	102, // 0110 = 01100110
	119, // 0111 = 01110111
	136, // 1000 = 10001000
	153, // 1001 = 10011001
	170, // 1010 = 10101010
	187, // 1011 = 10111011
	204, // 1100 = 11001100
	221, // 1101 = 11011101
	238, // 1110 = 11101110
	255  // 1111 = 11111111
};

const volatile unsigned char Three2Four[8] =
{
	 0, // 000 = 0000
     2, // 001 = 0010
	 4, // 010 = 0100
	 6, // 011 = 0110
	 9, // 100 = 1001
	11, // 101 = 1011
    13, // 110 = 1101
	15, // 111 = 1111
};

const volatile unsigned char Three2Eight[8] =
{
	  0, // 000 = 00000000
     36, // 001 = 00100100
	 73, // 010 = 01001001
	109, // 011 = 01101101
	146, // 100 = 10010010
	182, // 101 = 10110110
    219, // 110 = 11011011
	255, // 111 = 11111111
};
const volatile unsigned char Two2Eight[4] =
{
	  0, // 00 = 00000000
	 85, // 01 = 01010101
	170, // 10 = 10101010
	255  // 11 = 11111111
};

const volatile unsigned char One2Four[2] =
{
	 0, // 0 = 0000
	15, // 1 = 1111
};

const volatile unsigned char One2Eight[2] =
{
	  0, // 0 = 00000000
	255, // 1 = 11111111
};

static inline void UnswapCopyWrap(const u8 *src, u32 srcIdx, u8 *dest, u32 destIdx, u32 destMask, u32 numBytes)
{
	// copy leading bytes
	u32 leadingBytes = srcIdx & 3;
	if (leadingBytes != 0) {
		leadingBytes = 4 - leadingBytes;
		if ((u32)leadingBytes > numBytes)
			leadingBytes = numBytes;
		numBytes -= leadingBytes;

		srcIdx ^= 3;
		for (int i = 0; i < leadingBytes; i++) {
			dest[destIdx&destMask] = src[srcIdx];
			++destIdx;
			--srcIdx;
		}
		srcIdx += 5;
	}

	// copy dwords
	int numDWords = numBytes >> 2;
	while (numDWords--) {
		dest[(destIdx + 3) & destMask] = src[srcIdx++];
		dest[(destIdx + 2) & destMask] = src[srcIdx++];
		dest[(destIdx + 1) & destMask] = src[srcIdx++];
		dest[(destIdx + 0) & destMask] = src[srcIdx++];
		destIdx += 4;
	}

	// copy trailing bytes
	int trailingBytes = numBytes & 3;
	if (trailingBytes) {
		srcIdx ^= 3;
		for (int i = 0; i < trailingBytes; i++) {
			dest[destIdx&destMask] = src[srcIdx];
			++destIdx;
			--srcIdx;
		}
	}
}

static inline void DWordInterleaveWrap(u32 *src, u32 srcIdx, u32 srcMask, u32 numQWords)
{
	u32 tmp;
	while (numQWords--)	{
		tmp = src[srcIdx & srcMask];
		src[srcIdx & srcMask] = src[(srcIdx + 1) & srcMask];
		++srcIdx;
		src[srcIdx & srcMask] = tmp;
		++srcIdx;
	}
}

inline u16 swapword( u16 value )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		ax, word ptr [value]
		xchg	ah, al
	}
#else // WIN32_ASM
#ifdef ARM_ASM
	asm("rev16 %0, %0" : "+r"(value)::);
	return value;
#else
	return (value << 8) | (value >> 8);
#endif // ARM_ASM
#endif // WIN32_ASM
}

inline u16 RGBA8888_RGBA4444( u32 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		ebx, dword ptr [color]
		// R
		and		bl, 0F0h
		mov		ah, bl

		// G
		shr		bh, 4
		or		ah, bh

		bswap	ebx

		// B
		and		bh, 0F0h
		mov		al, bh

		// A
		shr		bl, 4
		or		al, bl
	}
#else // WIN32_ASM
	return ((color & 0x000000f0) <<  8) |	// r
			((color & 0x0000f000) >>  4) |	// g
			((color & 0x00f00000) >> 16) |	// b
			((color & 0xf0000000) >> 28);	// a
#endif // WIN32_ASM
}

inline u32 RGBA5551_RGBA8888( u16 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		ebx, 00000000h
		mov		cx, word ptr [color]
		xchg	cl, ch

		mov		bx, cx
		and		bx, 01h
        mov		al, byte ptr [One2Eight+ebx]

		mov		bx, cx
		shr		bx, 01h
		and		bx, 1Fh
		mov		ah, byte ptr [Five2Eight+ebx]

		bswap	eax

		mov		bx, cx
		shr		bx, 06h
		and		bx, 1Fh
		mov		ah, byte ptr [Five2Eight+ebx]

		mov		bx, cx
		shr		bx, 0Bh
		and		bx, 1Fh
		mov		al, byte ptr [Five2Eight+ebx]
	}
#else // WIN32_ASM
	color = swapword( color );
	u8 r, g, b, a;
	r = Five2Eight[color >> 11];
	g = Five2Eight[(color >> 6) & 0x001f];
	b = Five2Eight[(color >> 1) & 0x001f];
	a = One2Eight [(color     ) & 0x0001];
	return (a << 24) | (b << 16) | (g << 8) | r;
#endif // WIN32_ASM
}

// Just swaps the word
inline u16 RGBA5551_RGBA5551( u16 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		ax, word ptr [color]
		xchg	ah, al
	}
#else // WIN32_ASM
	return swapword( color );
#endif // WIN32_ASM
}

inline u32 IA88_RGBA8888( u16 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		cx, word ptr [color]

        mov		al, ch
		mov		ah, cl

		bswap	eax

		mov		ah, cl
		mov		al, cl
	}
#else // WIN32_ASM
	// ok
	u8 a = color >> 8;
	u8 i = color & 0x00FF;
	return (a << 24) | (i << 16) | (i << 8) | i;
#endif // WIN32_ASM
}

inline u16 IA88_RGBA4444( u16 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		cx, word ptr [color]

		shr		cl, 4
		mov		ah, cl
		shl		cl, 4
		or		ah, cl
		mov		al, cl

		shr		ch, 4
		or		al, ch
	}
#else // WIN32_ASM
	u8 i = color >> 12;
	u8 a = (color >> 4) & 0x000F;
	return (i << 12) | (i << 8) | (i << 4) | a;
#endif // WIN32_ASM
}

inline u16 IA44_RGBA4444( u8 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		cl, byte ptr [color]
		mov		al, cl

		shr		cl, 4
		mov		ah, cl
		shl		cl, 4
		or		ah, cl
	}
#else // WIN32_ASM
	return ((color & 0xf0) << 8) | ((color & 0xf0) << 4) | (color);
#endif // WIN32_ASM
}

inline u32 IA44_RGBA8888( u8 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		ebx, 00000000h
		mov		cl, byte ptr [color]

		mov		bl, cl
		shr		bl, 04h
		mov		ch, byte ptr [Four2Eight+ebx]

		mov		bl, cl
		and		bl, 0Fh
		mov		cl, byte ptr [Four2Eight+ebx]

        mov		al, cl
		mov		ah, ch

		bswap	eax

		mov		ah, ch
		mov		al, ch
	}
#else // WIN32_ASM
	u8 i = Four2Eight[color >> 4];
	u8 a = Four2Eight[color & 0x0F];
	return (a << 24) | (i << 16) | (i << 8) | i;
#endif // WIN32_ASM
}

inline u16 IA31_RGBA4444( u8 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		ebx, 00000000h
		mov		cl, byte ptr [color]

		mov		bl, cl
		shr		bl, 01h
		mov		ch, byte ptr [Three2Four+ebx]
		mov		ah, ch
		shl		ch, 4
		or		ah, ch
		mov		al, ch

		mov		bl, cl
		and		bl, 01h
		mov		ch, byte ptr [One2Four+ebx]
		or		al, ch
	}
#else // WIN32_ASM
	u8 i = Three2Four[color >> 1];
	u8 a = One2Four[color & 0x01];
	return (i << 12) | (i << 8) | (i << 4) | a;
#endif // WIN32_ASM
}

inline u32 IA31_RGBA8888( u8 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		ebx, 00000000h
		mov		cl, byte ptr [color]

		mov		bl, cl
		shr		bl, 01h
		mov		ch, byte ptr [Three2Eight+ebx]

		mov		bl, cl
		and		bl, 01h
		mov		cl, byte ptr [One2Eight+ebx]

        mov		al, cl
		mov		ah, ch

		bswap	eax

		mov		ah, ch
		mov		al, ch
	}
#else // WIN32_ASM
	u8 i = Three2Eight[color >> 1];
	u8 a = One2Eight[color & 0x01];
	return (i << 24) | (i << 16) | (i << 8) | a;
#endif // WIN32_ASM
}

inline u16 I8_RGBA4444( u8 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		cl, byte ptr [color]

		shr		cl, 4
		mov		al, cl
		shl		cl, 4
		or		al, cl
		mov		ah, al
	}
#else // WIN32_ASM
	u8 c = color >> 4;
	return (c << 12) | (c << 8) | (c << 4) | c;
#endif // WIN32_ASM
}

inline u32 I8_RGBA8888( u8 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		cl, byte ptr [color]

		mov		al, cl
		mov		ah, cl
		bswap	eax
		mov		ah, cl
		mov		al, cl
	}
#else // WIN32_ASM
	return (color << 24) | (color << 16) | (color << 8) | color;
#endif // WIN32_ASM
}

inline u16 I4_RGBA4444( u8 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		cl, byte ptr [color]
		mov		al, cl
		shl		cl, 4
		or		al, cl
		mov		ah, al
	}
#else // WIN32_ASM
	u16 ret = color & 0x0f;
	ret |= ret << 4;
	ret |= ret << 8;
	return ret;
#endif // WIN32_ASM
}

inline u32 I4_RGBA8888( u8 color )
{
#ifdef WIN32_ASM
	__asm
	{
		mov		ebx, 00000000h

		mov		bl, byte ptr [color]
		mov		cl, byte ptr [Four2Eight+ebx]

        mov		al, cl
		mov		ah, cl
		bswap	eax
		mov		ah, cl
		mov		al, cl
	}
#else // WIN32_ASM
	u8 c = Four2Eight[color];
	c |= c << 4;
	return (c << 24) | (c << 16) | (c << 8) | c;
#endif // WIN32_ASM
}

#endif // CONVERT_H