TEXTURE *material_map(const Vector3d& EPoint, const TEXTURE *Texture)
{
int reg_number = -1;
int Material_Number;
DBL xcoor = 0.0, ycoor = 0.0;
RGBFTColour colour;
/*
* Now we have transformed x, y, z we use image mapping routine to determine
* texture index.
*/
if(map_pos(EPoint, Texture->pattern.get(), &xcoor, &ycoor))
Material_Number = 0;
else
{
if (const ImagePatternImpl *pattern = dynamic_cast<ImagePatternImpl*>(Texture->pattern.get()))
image_colour_at(pattern->pImage, xcoor, ycoor, colour, ®_number); // TODO ALPHA - we should decide whether we prefer premultiplied or non-premultiplied alpha
else
POV_PATTERN_ASSERT(false);
if(reg_number == -1)
Material_Number = (int)(colour.red() * 255.0);
else
Material_Number = reg_number;
}
if(Material_Number > Texture->Materials.size())
Material_Number %= Texture->Materials.size();
return Texture->Materials[Material_Number % Texture->Materials.size()];
}
DBL image_pattern(const Vector3d& EPoint, const BasicPattern* pPattern)
{
DBL xcoor = 0.0, ycoor = 0.0;
int index = -1;
RGBFTColour colour;
const ImageData *image = dynamic_cast<const ImagePatternImpl*>(pPattern)->pImage;
DBL Value;
colour.Clear();
// going to have to change this
// need to know if bump point is off of image for all 3 points
if(map_pos(EPoint, pPattern, &xcoor, &ycoor))
return 0.0;
else
image_colour_at(image, xcoor, ycoor, colour, &index); // TODO ALPHA - we should decide whether we prefer premultiplied or non-premultiplied alpha
if((index == -1) || image->Use)
{
if(image->Use == USE_ALPHA)
{
// use alpha channel or red channel
if(image->data->HasTransparency() == true)
Value = colour.transm();
else
Value = colour.red(); // otherwise, just use the red channel
}
else
// use grey-scaled version of the color
Value = colour.Greyscale();
}
else
Value = index / 255.0;
if(Value < 0)
Value = 0;
else if(Value > 1.0)
Value = 1.0;
return Value;
}
void AlphaUnPremultiply(RGBFTColour& colour)
{
AlphaUnPremultiply(colour.red(), colour.green(), colour.blue(), colour.FTtoA());
}