private static void CheckBounds(this ProcessState state)
{
if (state.RegionHeight == 0 || state.RegionWidth == 0)
{
throw new ArgumentException("Width or Height can not be 0");
}
if (state.StartX < 0 || state.StartY < 0)
{
throw new ArgumentException("X or Y must be unsigned");
}
}
/// <summary>
/// Calculates the region, offset and final output image size
/// </summary>
/// <param name="request"></param>
/// <param name="originalWidth">Original width (pixels) of the source image</param>
/// <param name="originalHeight">Original height (pixels) of the source image</param>
/// <param name="allowSizeAboveFull">Allow output image dimensions to exceed that of the source image, but constrained by <see cref="ImageRequest.MaxWidth"/>,<see cref="ImageRequest.MaxHeight"/>,<see cref="ImageRequest.MaxArea"/></param>
/// <returns></returns>
static public ProcessState GetInterpretedValues(ImageRequest request, int originalWidth, int originalHeight, bool allowSizeAboveFull)
{
request.CheckRequest();
ProcessState state = new ProcessState();
state.StartX = state.StartY = state.RegionHeight = state.RegionWidth = 0;
state.OutputScale = state.ImageScale = 1;
switch (request.Region.Mode)
{
case ImageRegionMode.PercentageRegion:
state.StartX = Convert.ToInt32(request.Region.X / 100 * originalWidth);
state.StartY = Convert.ToInt32(request.Region.Y / 100 * originalHeight);
state.OutputWidth = state.RegionWidth = Convert.ToInt32(request.Region.Width / 100 * originalWidth);
state.OutputHeight = state.RegionHeight = Convert.ToInt32(request.Region.Height / 100 * originalHeight);
break;
case ImageRegionMode.Region:
state.StartX = Convert.ToInt32(request.Region.X);
state.StartY = Convert.ToInt32(request.Region.Y);
state.OutputWidth = state.RegionWidth = Convert.ToInt32(request.Region.Width);
state.OutputHeight = state.RegionHeight = Convert.ToInt32(request.Region.Height);
break;
case ImageRegionMode.Square:
state.OutputWidth = state.OutputHeight = state.RegionHeight = state.RegionWidth = Math.Min(originalWidth, originalHeight);
// pick the middle of the image
state.StartX = state.RegionWidth == originalWidth ? 0 : Convert.ToInt32(Math.Round((originalWidth - originalHeight) / 2f));
state.StartY = state.RegionHeight == originalHeight ? 0 : Convert.ToInt32(Math.Round((originalHeight - originalWidth) / 2f));
break;
default:
state.OutputWidth = state.RegionWidth = originalWidth;
state.OutputHeight = state.RegionHeight = originalHeight;
break;
}
CheckBounds(state);
switch (request.Size.Mode)
{
case ImageSizeMode.Max:
case ImageSizeMode.Full:
// no changes needed as scale and OutputWidth/Height are set
break;
case ImageSizeMode.PercentageScaled:
state.OutputWidth = Convert.ToInt32(state.RegionWidth * request.Size.Percent.Value);
state.OutputHeight = Convert.ToInt32(state.RegionHeight * request.Size.Percent.Value);
state.OutputScale = request.Size.Percent.Value;
break;
case ImageSizeMode.Distort:
float scaledx, scaledy = 1f;
scaledy = request.Size.Height / (float)state.RegionHeight;
scaledx = request.Size.Width / (float)state.RegionWidth;
state.OutputWidth = Convert.ToInt32(state.RegionWidth * scaledx);
state.OutputHeight = Convert.ToInt32(state.RegionHeight * scaledy);
if (scaledx < scaledy)
{
state.OutputScale = scaledx;
}
else
{
state.OutputScale = scaledy;
}
if (request.Region.Mode != ImageRegionMode.Full)
{
if (scaledx < scaledy)
{
state.ImageScale = scaledx;
}
else
{
state.ImageScale = scaledy;
}
}
break;
case ImageSizeMode.MaintainAspectRatio:
if (request.Size.Width != 0 && request.Size.Height == 0)
{
var scale = request.Size.Width / (float)state.RegionWidth;
state.OutputWidth = Convert.ToInt32(state.RegionWidth * scale);
state.OutputHeight = Convert.ToInt32(state.RegionHeight * scale);
state.OutputScale = scale;
}
else if (request.Size.Width == 0 && request.Size.Height != 0)
{
var scale = request.Size.Height / (float)state.RegionHeight;
state.OutputWidth = Convert.ToInt32(state.RegionWidth * scale);
state.OutputHeight = Convert.ToInt32(state.RegionHeight * scale);
state.OutputScale = scale;
}
else
{
var originalScale = originalWidth / (float)originalHeight;
var scale = Math.Min((request.Size.Height / (float)state.RegionHeight), (request.Size.Width / (float)state.RegionWidth));
state.OutputWidth = Convert.ToInt32(state.RegionWidth * scale);
state.OutputHeight = Convert.ToInt32(state.RegionHeight * scale);
state.OutputScale = scale;
if (request.Region.Mode != ImageRegionMode.Full)
{
state.ImageScale = scale;
}
}
break;
}
// final bounds reduction
float max_scale = 1f;
(state.OutputWidth, state.OutputHeight, max_scale)
= ScaleOutput(request.MaxWidth, request.MaxHeight, state.OutputWidth, state.OutputHeight, allowSizeAboveFull);
state.OutputScale = Math.Min(max_scale, state.ImageScale);
state.CheckBounds();
return(state);
}
