public ImageFilm(int xResolution, int yResolution, Filter filter, float[] cropWindow)
: base(xResolution, yResolution)
{
_filter = filter;
_cropWindow = cropWindow;
_bitmap = new WriteableBitmap(xResolution, yResolution, 96.0, 96.0, PixelFormats.Pbgra32, null);
// Compute film image extent
_xPixelStart = MathUtility.Ceiling(xResolution * cropWindow[0]);
_xPixelCount = Math.Max(1, MathUtility.Ceiling(xResolution * cropWindow[1]) - _xPixelStart);
_yPixelStart = MathUtility.Ceiling(yResolution * cropWindow[2]);
_yPixelCount = Math.Max(1, MathUtility.Ceiling(yResolution * cropWindow[3]) - _yPixelStart);
// Allocate film image storage
_pixels = new ImagePixel[_xPixelCount, _yPixelCount];
for (var x = 0; x < _xPixelCount; x++)
for (var y = 0; y < _yPixelCount; y++)
_pixels[x, y] = new ImagePixel();
// Precompute filter weight table
_filterTable = new float[FilterTableSize * FilterTableSize];
var index = 0;
for (int y = 0; y < FilterTableSize; ++y)
{
float fy = (y + .5f) * filter.YWidth / FilterTableSize;
for (int x = 0; x < FilterTableSize; ++x)
{
float fx = (x + .5f) * filter.XWidth / FilterTableSize;
_filterTable[index++] = filter.Evaluate(fx, fy);
}
}
_bgra = new byte[_xPixelCount * _yPixelCount * 4];
}
public static Film MakeFilm(string name, ParamSet parameters, Filter filter)
{
switch (name)
{
case "image" :
{
var xres = parameters.FindInt32("xresolution", 640);
var yres = parameters.FindInt32("yresolution", 480);
var cropWindow = parameters.FindSingleList("cropwindow");
if (cropWindow.Length == 0)
cropWindow = new float[] { 0, 1, 0, 1 };
return new ImageFilm(xres, yres, filter, cropWindow);
}
default:
throw new ArgumentException("Unknown film: " + name);
}
}