mirror of
https://github.com/godotengine/godot.git
synced 2025-10-31 05:31:01 +00:00
121 lines
4 KiB
C++
121 lines
4 KiB
C++
/* -----------------------------------------------------------------------------
|
|
|
|
Copyright (c) 2006 Simon Brown si@sjbrown.co.uk
|
|
|
|
Permission is hereby granted, free of charge, to any person obtaining
|
|
a copy of this software and associated documentation files (the
|
|
"Software"), to deal in the Software without restriction, including
|
|
without limitation the rights to use, copy, modify, merge, publish,
|
|
distribute, sublicense, and/or sell copies of the Software, and to
|
|
permit persons to whom the Software is furnished to do so, subject to
|
|
the following conditions:
|
|
|
|
The above copyright notice and this permission notice shall be included
|
|
in all copies or substantial portions of the Software.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
|
|
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
|
|
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
|
|
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
|
|
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
|
|
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
|
|
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
|
|
|
-------------------------------------------------------------------------- */
|
|
|
|
#include "colourset.h"
|
|
|
|
namespace squish {
|
|
|
|
ColourSet::ColourSet( u8 const* rgba, int mask, int flags )
|
|
: m_count( 0 ),
|
|
m_transparent( false )
|
|
{
|
|
// check the compression mode for dxt1
|
|
bool isDxt1 = ( ( flags & kDxt1 ) != 0 );
|
|
bool weightByAlpha = ( ( flags & kWeightColourByAlpha ) != 0 );
|
|
|
|
// create the minimal set
|
|
for( int i = 0; i < 16; ++i )
|
|
{
|
|
// check this pixel is enabled
|
|
int bit = 1 << i;
|
|
if( ( mask & bit ) == 0 )
|
|
{
|
|
m_remap[i] = -1;
|
|
continue;
|
|
}
|
|
|
|
// check for transparent pixels when using dxt1
|
|
if( isDxt1 && rgba[4*i + 3] < 128 )
|
|
{
|
|
m_remap[i] = -1;
|
|
m_transparent = true;
|
|
continue;
|
|
}
|
|
|
|
// loop over previous points for a match
|
|
for( int j = 0;; ++j )
|
|
{
|
|
// allocate a new point
|
|
if( j == i )
|
|
{
|
|
// normalise coordinates to [0,1]
|
|
float x = ( float )rgba[4*i] / 255.0f;
|
|
float y = ( float )rgba[4*i + 1] / 255.0f;
|
|
float z = ( float )rgba[4*i + 2] / 255.0f;
|
|
|
|
// ensure there is always non-zero weight even for zero alpha
|
|
float w = ( float )( rgba[4*i + 3] + 1 ) / 256.0f;
|
|
|
|
// add the point
|
|
m_points[m_count] = Vec3( x, y, z );
|
|
m_weights[m_count] = ( weightByAlpha ? w : 1.0f );
|
|
m_remap[i] = m_count;
|
|
|
|
// advance
|
|
++m_count;
|
|
break;
|
|
}
|
|
|
|
// check for a match
|
|
int oldbit = 1 << j;
|
|
bool match = ( ( mask & oldbit ) != 0 )
|
|
&& ( rgba[4*i] == rgba[4*j] )
|
|
&& ( rgba[4*i + 1] == rgba[4*j + 1] )
|
|
&& ( rgba[4*i + 2] == rgba[4*j + 2] )
|
|
&& ( rgba[4*j + 3] >= 128 || !isDxt1 );
|
|
if( match )
|
|
{
|
|
// get the index of the match
|
|
int index = m_remap[j];
|
|
|
|
// ensure there is always non-zero weight even for zero alpha
|
|
float w = ( float )( rgba[4*i + 3] + 1 ) / 256.0f;
|
|
|
|
// map to this point and increase the weight
|
|
m_weights[index] += ( weightByAlpha ? w : 1.0f );
|
|
m_remap[i] = index;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// square root the weights
|
|
for( int i = 0; i < m_count; ++i )
|
|
m_weights[i] = std::sqrt( m_weights[i] );
|
|
}
|
|
|
|
void ColourSet::RemapIndices( u8 const* source, u8* target ) const
|
|
{
|
|
for( int i = 0; i < 16; ++i )
|
|
{
|
|
int j = m_remap[i];
|
|
if( j == -1 )
|
|
target[i] = 3;
|
|
else
|
|
target[i] = source[j];
|
|
}
|
|
}
|
|
|
|
} // namespace squish
|