bool GLTextureCubeMap::set( GLCubeMapFace face,
Array2DReadView< uint8x4 > data, GLImageFormat format,
const Vector2i& dstOffset )
{
if( dstOffset.x + data.width() > sideLength() ||
dstOffset.y + data.height() > sideLength() )
{
return false;
}
if( format != GLImageFormat::RGBA &&
format != GLImageFormat::BGRA )
{
return false;
}
//glPushClientAttribDefaultEXT( GL_CLIENT_PIXEL_STORE_BIT );
// TODO: alignment, strides, ..., has to be packed
// DSA treats a cube map as a 2D array texture.
glTextureSubImage3D
(
id(), 0,
dstOffset.x, dstOffset.y, static_cast< int >( face ),
data.width(), data.height(), 1, // 1 face
static_cast< GLenum >( format ), GL_UNSIGNED_BYTE,
data.pointer()
);
//glPopClientAttrib();
return true;
}
// static
bool PortableFloatMapIO::write( const std::string& filename, Array2DReadView< Vector4f > image )
{
int w = image.width();
int h = image.height();
// use "wb" binary mode to ensure that on Windows,
// newlines in the header are written out as '\n'
FILE* pFile = fopen( filename.c_str(), "wb" );
if( pFile == nullptr )
{
return false;
}
// write header
int nCharsWritten = fprintf( pFile, "PF4\n%d %d\n-1\n", w, h );
if( nCharsWritten < 0 )
{
fclose( pFile );
return false;
}
// All at once.
if( image.packed() )
{
fwrite( image.rowPointer( 0 ), sizeof( Vector4f ), image.numElements(), pFile );
}
// Row by Row.
else if( image.elementsArePacked() )
{
for( int y = 0; y < h; ++y )
{
fwrite( image.rowPointer( y ), sizeof( Vector4f ), image.width(), pFile );
}
}
// Element by element.
else
{
for( int y = 0; y < h; ++y )
{
for( int x = 0; x < w; ++x )
{
fwrite( image.elementPointer( { x, y } ), sizeof( Vector4f ), 1, pFile );
}
}
}
fclose( pFile );
return true;
}
void extractBackgroundColor( Array2DReadView< uint8x4 > composite,
Array2DReadView< uint8x4 > foreground,
Array2DWriteView< uint8x4 > background )
{
for( int y = 0; y < composite.height(); ++y )
{
for( int x = 0; x < composite.width(); ++x )
{
Vector4f cRGBA = toFloat( composite[ { x, y } ] );
Vector4f fRGBA = toFloat( foreground[ { x, y } ] );
Vector4f bRGBA = extractBackgroundColor( cRGBA, fRGBA );
background[ { x, y } ] = toUInt8( bRGBA );
}
}
}
// static
bool PNGIO::write( const std::string& filename,
Array2DReadView< uint16_t > image )
{
// TODO: use BitPacking::byteSwap16 on the buffer once it supports a
// destination.
Array2D< uint16_t > tmpImage( image.size() );
libcgt::core::arrayutils::map( image, tmpImage.writeView(),
[&] ( uint16_t z )
{
return byteSwap16( z );
}
);
const uint8_t* srcPointer = reinterpret_cast< const uint8_t* >(
tmpImage.pointer() );
unsigned int errVal = lodepng::encode(
filename, srcPointer, image.width(), image.height(), LCT_GREY, 16U );
bool succeeded = ( errVal == 0 );
return succeeded;
}
void over( Array2DReadView< Vector4f > foreground,
Array2DReadView< Vector4f > background,
Array2DWriteView< Vector4f > output )
{
for( int y = 0; y < foreground.height(); ++y )
{
for( int x = 0; x < foreground.width(); ++x )
{
Vector4f f = foreground[ { x, y } ];
Vector4f b = background[ { x, y } ];
float fa = f.w;
float ba = b.w;
Vector3f compositeColor = fa * f.xyz + ( 1.f - fa ) * ( b.xyz );
float compositeAlpha = fa + ba * ( 1 - fa );
output[ { x, y } ] = Vector4f( compositeColor, compositeAlpha );
}
}
}
// static
bool PNGIO::write( const std::string& filename,
Array2DReadView< uint8x4 > image )
{
Array2D< uint8x4 > tmpImage;
const uint8_t* srcPointer;
if( !image.packed() )
{
tmpImage.resize( image.size() );
copy< uint8x4 >( image, tmpImage );
srcPointer = reinterpret_cast< const uint8_t* >( tmpImage.pointer() );
}
else
{
srcPointer = reinterpret_cast< const uint8_t* >( image.pointer() );
}
unsigned int errVal = lodepng::encode(
filename, srcPointer, image.width(), image.height(), LCT_RGBA );
bool succeeded = ( errVal == 0 );
return succeeded;
}
void extractBackgroundColor( Array2DReadView< Vector4f > composite,
Array2DReadView< Vector4f > foreground,
Array2DWriteView< Vector4f > background )
{
// red channel:
// c_r = f_a * f_r + ( 1 - f_a ) * b_r
// b_r = ( c_r - f_a * f_r ) / ( 1 - f_a )
//
// alpha channel:
// c_a = f_a + b_a * ( 1 - f_a )
// b_a = ( c_a - f_a ) / ( 1 - f_a )
for( int y = 0; y < composite.height(); ++y )
{
for( int x = 0; x < composite.width(); ++x )
{
Vector4f cRGBA = composite[ { x, y } ];
Vector4f fRGBA = foreground[ { x, y } ];
Vector4f bRGBA = extractBackgroundColor( cRGBA, fRGBA );
background[ { x, y } ] = bRGBA;
}
}
}