107 lines
2.3 KiB
C++
107 lines
2.3 KiB
C++
// -- GODOT start --
|
|
|
|
#include "ForceInline.hpp"
|
|
#include "ProcessRgtc.hpp"
|
|
|
|
#include <assert.h>
|
|
#include <string.h>
|
|
|
|
static const uint8_t AlphaIndexTable[8] = { 1, 7, 6, 5, 4, 3, 2, 0 };
|
|
|
|
static etcpak_force_inline uint64_t ProcessAlpha( const uint8_t* src )
|
|
{
|
|
uint8_t solid8 = *src;
|
|
uint16_t solid16 = uint16_t( solid8 ) | ( uint16_t( solid8 ) << 8 );
|
|
uint32_t solid32 = uint32_t( solid16 ) | ( uint32_t( solid16 ) << 16 );
|
|
uint64_t solid64 = uint64_t( solid32 ) | ( uint64_t( solid32 ) << 32 );
|
|
if( memcmp( src, &solid64, 8 ) == 0 && memcmp( src+8, &solid64, 8 ) == 0 )
|
|
{
|
|
return solid8;
|
|
}
|
|
|
|
uint8_t min = src[0];
|
|
uint8_t max = min;
|
|
for( int i=1; i<16; i++ )
|
|
{
|
|
const auto v = src[i];
|
|
if( v > max ) max = v;
|
|
else if( v < min ) min = v;
|
|
}
|
|
|
|
uint32_t range = ( 8 << 13 ) / ( 1 + max - min );
|
|
uint64_t data = 0;
|
|
for( int i=0; i<16; i++ )
|
|
{
|
|
uint8_t a = src[i] - min;
|
|
uint64_t idx = AlphaIndexTable[( a * range ) >> 13];
|
|
data |= idx << (i*3);
|
|
}
|
|
|
|
return max | ( min << 8 ) | ( data << 16 );
|
|
}
|
|
|
|
void CompressRgtcR(const uint32_t *src, uint64_t *dst, uint32_t blocks, size_t width)
|
|
{
|
|
int i = 0;
|
|
auto ptr = dst;
|
|
do
|
|
{
|
|
uint32_t rgba[4 * 4];
|
|
uint8_t r[4 * 4];
|
|
|
|
auto tmp = (char *)rgba;
|
|
memcpy(tmp, src + width * 0, 4 * 4);
|
|
memcpy(tmp + 4 * 4, src + width * 1, 4 * 4);
|
|
memcpy(tmp + 8 * 4, src + width * 2, 4 * 4);
|
|
memcpy(tmp + 12 * 4, src + width * 3, 4 * 4);
|
|
src += 4;
|
|
if (++i == width / 4)
|
|
{
|
|
src += width * 3;
|
|
i = 0;
|
|
}
|
|
|
|
for (int i = 0; i < 16; i++)
|
|
{
|
|
r[i] = rgba[i] & 0x000000FF;
|
|
}
|
|
*ptr++ = ProcessAlpha(r);
|
|
}
|
|
while (--blocks);
|
|
}
|
|
|
|
void CompressRgtcRG(const uint32_t *src, uint64_t *dst, uint32_t blocks, size_t width)
|
|
{
|
|
int i = 0;
|
|
auto ptr = dst;
|
|
do
|
|
{
|
|
uint32_t rgba[4 * 4];
|
|
uint8_t r[4 * 4];
|
|
uint8_t g[4 * 4];
|
|
|
|
auto tmp = (char *)rgba;
|
|
memcpy(tmp, src + width * 0, 4 * 4);
|
|
memcpy(tmp + 4 * 4, src + width * 1, 4 * 4);
|
|
memcpy(tmp + 8 * 4, src + width * 2, 4 * 4);
|
|
memcpy(tmp + 12 * 4, src + width * 3, 4 * 4);
|
|
src += 4;
|
|
if (++i == width / 4)
|
|
{
|
|
src += width * 3;
|
|
i = 0;
|
|
}
|
|
|
|
for (int i = 0; i < 16; i++)
|
|
{
|
|
r[i] = rgba[i] & 0x000000FF;
|
|
g[i] = (rgba[i] & 0x0000FF00) >> 8;
|
|
}
|
|
*ptr++ = ProcessAlpha(r);
|
|
*ptr++ = ProcessAlpha(g);
|
|
}
|
|
while (--blocks);
|
|
}
|
|
|
|
// -- GODOT end --
|