engine: common: imagelib: img_png.c: fix wrong palette decoding.

This commit is contained in:
Andrey Akhmichin 2022-12-04 02:33:36 +05:00 committed by Alibek Omarov
parent 0c4f35e2d0
commit 7bb994f7bc
1 changed files with 18 additions and 7 deletions

View File

@ -43,7 +43,7 @@ qboolean Image_LoadPNG( const char *name, const byte *buffer, fs_offset_t filesi
short p, a, b, c, pa, pb, pc;
byte *buf_p, *pixbuf, *raw, *prior, *idat_buf = NULL, *uncompressed_buffer = NULL;
byte *pallete = NULL, *trns = NULL;
uint chunk_len, trns_len, crc32, crc32_check, oldsize = 0, newsize = 0, rowsize;
uint chunk_len, trns_len, plte_len, crc32, crc32_check, oldsize = 0, newsize = 0, rowsize;
uint uncompressed_size, pixel_size, pixel_count, i, y, filter_type, chunk_sign, r_alpha, g_alpha, b_alpha;
qboolean has_iend_chunk = false;
z_stream stream = {0};
@ -163,7 +163,7 @@ qboolean Image_LoadPNG( const char *name, const byte *buffer, fs_offset_t filesi
}
// move pointer
buf_p += sizeof( chunk_sign );
buf_p += sizeof( chunk_len );
// find transparency
if( !memcmp( buf_p, trns_sign, sizeof( trns_sign ) ) )
@ -175,6 +175,7 @@ qboolean Image_LoadPNG( const char *name, const byte *buffer, fs_offset_t filesi
else if( !memcmp( buf_p, plte_sign, sizeof( plte_sign ) ) )
{
pallete = buf_p + sizeof( plte_sign );
plte_len = chunk_len / 3;
}
// get all IDAT chunks data
else if( !memcmp( buf_p, idat_sign, sizeof( idat_sign ) ) )
@ -467,14 +468,24 @@ qboolean Image_LoadPNG( const char *name, const byte *buffer, fs_offset_t filesi
case PNG_CT_PALLETE:
for( y = 0; y < pixel_count; y++, raw += pixel_size )
{
*pixbuf++ = pallete[raw[0] + 2];
*pixbuf++ = pallete[raw[0] + 1];
*pixbuf++ = pallete[raw[0] + 0];
if( raw[0] < plte_len )
{
*pixbuf++ = pallete[3 * raw[0] + 0];
*pixbuf++ = pallete[3 * raw[0] + 1];
*pixbuf++ = pallete[3 * raw[0] + 2];
if( trns && raw[0] < trns_len )
*pixbuf++ = trns[raw[0]];
if( trns && raw[0] < trns_len )
*pixbuf++ = trns[raw[0]];
else
*pixbuf++ = 0xFF;
}
else
{
*pixbuf++ = 0;
*pixbuf++ = 0;
*pixbuf++ = 0;
*pixbuf++ = 0xFF;
}
}
break;
default: