/*
===================
R_ImageAdd
===================
*/
static void R_ImageAdd( byte *data1, int width1, int height1, byte *data2, int width2, int height2 ) {
int i, j;
int c;
byte *newMap;
// resample pic2 to the same size as pic1
if ( width2 != width1 || height2 != height1 ) {
newMap = R_Dropsample( data2, width2, height2, width1, height1 );
data2 = newMap;
} else {
newMap = NULL;
}
c = width1 * height1 * 4;
for ( i = 0 ; i < c ; i++ ) {
j = data1[i] + data2[i];
if ( j > 255 ) {
j = 255;
}
data1[i] = j;
}
if ( newMap ) {
R_StaticFree( newMap );
}
}
/*
===================
R_AddNormalMaps
===================
*/
static void R_AddNormalMaps( byte *data1, int width1, int height1, byte *data2, int width2, int height2 )
{
int i, j;
byte *newMap;
// resample pic2 to the same size as pic1
if( width2 != width1 || height2 != height1 )
{
newMap = R_Dropsample( data2, width2, height2, width1, height1 );
data2 = newMap;
}
else
{
newMap = NULL;
}
// add the normal change from the second and renormalize
for( i = 0; i < height1; i++ )
{
for( j = 0; j < width1; j++ )
{
byte *d1, *d2;
idVec3 n;
float len;
d1 = data1 + ( i * width1 + j ) * 4;
d2 = data2 + ( i * width1 + j ) * 4;
n[0] = ( d1[0] - 128 ) / 127.0;
n[1] = ( d1[1] - 128 ) / 127.0;
n[2] = ( d1[2] - 128 ) / 127.0;
// There are some normal maps that blend to 0,0,0 at the edges
// this screws up compression, so we try to correct that here by instead fading it to 0,0,1
len = n.LengthFast();
if( len < 1.0f )
{
n[2] = idMath::Sqrt( 1.0 - ( n[0] * n[0] ) - ( n[1] * n[1] ) );
}
n[0] += ( d2[0] - 128 ) / 127.0;
n[1] += ( d2[1] - 128 ) / 127.0;
n.Normalize();
d1[0] = ( byte )( n[0] * 127 + 128 );
d1[1] = ( byte )( n[1] * 127 + 128 );
d1[2] = ( byte )( n[2] * 127 + 128 );
d1[3] = 255;
}
}
if( newMap )
{
R_StaticFree( newMap );
}
}
